ACTUATOR WITH MODULAR FAIL-SAFE ASSEMBLY

Abstract

A modular actuator is provided. The modular actuator includes a motor, a drive device, and a housing. The drive device is driven by the motor and coupled to a movable component for driving the movable component. The housing houses the motor and the drive device therein, and supports modular interfacing with a plurality of fail-safe assemblies, one at a time.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application claims the benefit of and priority to Indian Provisional Application No. 202321055242, filed Aug. 17, 2023, the entire disclosure of which is incorporated reference herein.

BACKGROUND

The present disclosure relates generally to actuators. More particularly, the present disclosure relates to an actuator having modular fail-safe assemblies for use in a heating, ventilating, air conditioning, and/or refrigeration (HVAC&R) system.

Actuators are used to operate a wide variety of HVAC&R components such as air dampers, fluid valves, air handling units, and other components that are typically used in HVAC&R systems. For example, an actuator may be coupled to a damper in an HVAC&R system and may be used to drive the damper between an open position and a closed position.

Different types of actuators are tailored to different applications. As a result, an actuator manufacturer is required to maintain different store keeping units (SKUs) or variants for the same torque rating actuator. For example, for a 5 Nm actuator, different variants (such as a non-fail-safe actuator, a capacitor return fail-safe actuator, and a spring return fail-safe actuator) are maintained for different applications. Maintaining SKUs for actuator variants escalates inventory, assembly, and storage costs, which is undesirable.

SUMMARY

The following presents a summary of one or more implementations of the present disclosure in order to provide an understanding of such implementations. This summary is not an extensive overview of all contemplated implementations, and is intended to neither identify key or critical elements of all implementations nor delineate the scope of any or all implementations. Its sole purpose is to present some concepts of one or more implementations of the present disclosure in a form as a prelude to the more detailed description that is presented later.

One implementation of the present disclosure relates to a modular actuator. The modular actuator includes a motor, a drive device, and a housing. The drive device is driven by the motor and coupled to a movable component for driving the movable component. The housing is configured to house the motor and the drive device therein, and support modular interfacing with fail-safe assemblies (e.g., one at a time).

In some embodiments, in absence of a fail-safe assembly, the movable component retains a last position in response to power failure or control signal failure.

In some embodiments, when any of the fail-safe assemblies is coupled to the housing, coupled fail-safe assembly operates the motor to drive the movable component from a last position to a fail-safe position in response to power failure or control signal failure.

In some embodiments, the fail-safe position is one of an open position and a closed position of the movable component.

In some embodiments, the fail-safe assemblies include a spring return fail-safe assembly and a capacitor return fail-safe assembly.

In some embodiments, the housing includes a base portion and a top cover portion. The motor and the drive device are housed within the base portion, and the top cover portion is removably coupled to conceal an opening of the base portion.

In some embodiments, the base portion is provided with a seal member for ingress protection.

In some embodiments, the base portion includes a modular interface that enables a fail-safe assembly among the plurality of fail-safe assemblies to be removably coupled to the opening of the base portion upon removal of the top cover portion.

In some embodiments, the base portion further includes one or more spring-loaded electrical connectors electrically coupled to the motor.

In some embodiments, the one or more spring-loaded electrical connectors are held in a depressed state when the top cover portion is coupled to the base portion, and the one or more spring-loaded electrical connectors extend out of the base portion in response to removal of the top cover portion from the base portion.

In some embodiments, the extended one or more spring-loaded electrical connectors are configured to make conductive contact with a capacitor return fail-safe assembly, among the plurality of fail-safe assemblies, removably coupled to the base portion.

In some embodiments, the one or more spring-loaded electrical connectors regain the depressed state without making conductive contact when a spring return fail-safe assembly, among the plurality of fail-safe assemblies, is removably coupled to the base portion.

In some embodiments, the spring return fail-safe assembly, removably coupled to the base portion, is configured to form a mechanical linkage with the drive device.

In some embodiments, a return stroke of the modular actuator is controlled based on a spring action of the coupled spring return fail-safe assembly.

In some embodiments, the modular actuator further includes processing circuitry configured to determine which fail-safe assembly among the plurality of fail-safe assemblies is removably coupled to the base portion.

In some embodiments, the processing circuitry determines which fail-safe assembly among the plurality of fail-safe assemblies is removably coupled to the base portion based on whether the one or more spring-loaded electrical connectors have made a conductive contact with the removably coupled fail-safe assembly.

Another implementation of the present disclosure relates to a modular fail-safe assembly for actuators. The modular fail-safe assembly includes a return mechanism and a housing. The housing is configured to house the return mechanism and support modular interfacing with a non-fail-safe actuator. The return mechanism is configured to implement a fail-safe operation in the non-fail-safe actuator in response to power failure or control signal failure and is removably coupled to the modular fail-safe assembly.

In some embodiments, the return mechanism includes a capacitor.

In some embodiments, the return mechanism includes a spring.

Yet another implementation of the present disclosure relates to actuator system for use in a heating, ventilating, or air conditioning (HVAC) system to drive a movable HVAC component. The actuator system includes one or more fail-safe assemblies provided as modular attachments. The actuator system further includes a modular actuator configured to support modular interfacing with the one or more fail-safe assemblies, (e.g., one at a time). In response to power failure or control signal failure, a fail-safe assembly, of the one or more fail-safe assemblies, is removably coupled to the modular actuator and is configured to implement a fail-safe operation that drives the movable HVAC component to a fail-safe position.

Additional advantages and novel features relating to implementations of the present disclosure will be set forth in part in the description that follows, and in part will become more apparent to those skilled in the art upon examination of the following or upon learning by practice thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Various objects, aspects, features, and advantages of the disclosure will become more apparent and better understood by referring to the detailed description taken in conjunction with the accompanying drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing figures are not necessarily drawn to scale and certain figures may be shown in exaggerated or generalized form in the interest of clarity and conciseness.

FIG. 1 is a schematic drawing of a building equipped with a heating, ventilating, air conditioning, and/or refrigeration (HVAC&R) system and/or a building management system (BMS), according to some exemplary embodiments of the present disclosure.

FIG. 2 is a schematic diagram of a waterside system which may be used to support the HVAC&R system of FIG. 1, according to some exemplary embodiments of the present disclosure.

FIG. 3 is a block diagram of an airside system which may be used as part of the HVAC&R system of FIG. 1, according to some exemplary embodiments of the present disclosure.

FIG. 4 is a block diagram of a BMS which may be implemented in the building of FIG. 1, according to some exemplary embodiments of the present disclosure.

FIGS. 5-7 are drawings of an actuator which may be used in the HVAC&R system of FIG. 1, the waterside system of FIG. 2, the airside system of FIG. 3, or the BMS of FIG. 4 to control an HVAC component, according to some exemplary embodiments of the present disclosure.

FIGS. 8A-8C are block diagrams that illustrate a modular actuator system for use in an HVAC&R system, according to some exemplary embodiments of the present disclosure.

FIGS. 9-11 are block diagrams that demonstrate modular interfacing of actuator of FIG. 8A with the one or more fail-safe assemblies (e.g., a spring return fail-safe assembly and a capacitor return fail-safe assembly) of FIGS. 8B and 8C, according to some embodiments of the present disclosure.

FIG. 12 is a flow diagram of a method to describe operation of the modular actuator of FIG. 8A, in accordance with some embodiments of the present disclosure.

DETAILED DESCRIPTION

Overview

Referring generally to the FIGURES, a modular actuator system is shown, according to an exemplary embodiment. The modular actuator system may be a damper actuator, a valve actuator, a fan actuator, a pump actuator, or any other type of actuator that can be used in building system such as a heating, ventilating, air conditioning, and/or refrigeration (HVAC&R) system.

The present disclosure provides a modular actuator system for driving a movable component (for example, a damper, a valve, a fan, a pump, or the like) between a number of positions. The actuator system includes fail-safe assemblies provided as modular attachments and an actuator configured to support modular interfacing with the fail-safe assemblies, one at a time. Examples of the fail-safe assemblies may include a spring return fail-safe assembly and a capacitor return fail-safe assembly. Systems and methods provide an actuator that alleviates drawbacks described above without compromising on application suitability.

Inherently, the actuator may be a non-fail-safe actuator such that in an event of power failure or control signal failure, the movable component retains its last position (for example, remains in the last position at the time power failure or control signal failure) until the power or control signal is restored. However, when one of the fail-safe assemblies is removably coupled to the actuator, the coupled fail-safe assembly implements a fail-safe operation in an event of power failure or control signal failure. Thus, driving the movable component to a fail-safe position from its last position.

Both fail-safe and non-fail-safe actuators are tailored to specific applications. In fact, type of return mechanism (e.g., spring return or capacitor return) also dictates the suitability of fail-safe actuators for diverse applications. Thus, by providing the modular actuator system, an equipment manufacturer is not required to maintain different store keeping units (SKUs) or variants for the same torque rating actuator. The manufacturer may simply maintain a common actuator which can be modularly interfaced with different fail-safe assemblies as per requirement. Thus, reducing the inventory, assembly, and storage costs. Further, such modularity enables switching from one actuator type to another without complete replacement. For example, the non-fail-safe actuator can be easily converted to function as a spring return actuator by coupling (or attaching) therewith the spring return fail-safe assembly or a capacitor return actuator by coupling (or attaching) therewith the capacitor return fail-safe assembly. In addition, the spring return actuator can be easily converted to the capacitor return actuator by swapping the spring return fail-safe assembly with the capacitor return fail-safe assembly, or vice versa. Thus, providing more flexibility to customers.

Before turning to the Figures, it should be understood that the disclosure is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting.

Referring generally to the Figures, a modular actuator, modular fail-safe assemblies, and a modular actuator system are shown and described.

Building Management System and HVAC&R System

Referring now to FIGS. 1-4, an exemplary building management system (BMS) and heating, ventilating, air conditioning, and/or refrigeration (HVAC&R) system in which the systems and methods of the present disclosure may be implemented are shown, according to some exemplary embodiments. Referring particularly to FIG. 1, a perspective view of a building 10 is shown, according to some exemplary embodiments of the present disclosure. The building 10 is served by a BMS. A BMS is, in general, a system of devices configured to control, monitor, and manage equipment in or around a building or building area. A BMS can include, for example, an HVAC&R system, a security system, a lighting system, a fire alerting system, any other system that is capable of managing building functions or devices, or any combination thereof.

The BMS that serves the building 10 may include an HVAC&R system 100. The HVAC&R system 100 may include a plurality of HVAC&R devices (e.g., heaters, chillers, air handling units, pumps, fans, thermal energy storage, etc.) configured to provide heating, cooling, ventilation, or other services for the building 10. For example, the HVAC&R system 100 is shown to include a waterside system 120 and an airside system 130. The waterside system 120 may provide a heated or chilled fluid to an air handling unit of the airside system 130. The airside system 130 may use the heated or chilled fluid to heat or cool an airflow provided to the building 10. An exemplary waterside system and airside system which may be used in the HVAC&R system 100 are described in greater detail with reference to FIGS. 2-3.

The HVAC&R system 100 is shown to include a chiller 102, a boiler 104, and a rooftop air handling unit (AHU) 106. The waterside system 120 may use the boiler 104 and the chiller 102 to heat or cool a working fluid (e.g., water, glycol, etc.) and may circulate the working fluid to the AHU 106. In various embodiments, the HVAC&R devices of the waterside system 120 may be located in or around the building 10 (as shown in FIG. 1) or at an offsite location such as a central plant (e.g., a chiller plant, a steam plant, a heat plant, etc.). The working fluid may be heated in the boiler 104 or cooled in the chiller 102, depending on whether heating or cooling is required in the building 10. The boiler 104 may add heat to the circulated fluid, for example, by burning a combustible material (e.g., natural gas) or using an electric heating element. The chiller 102 may place the circulated fluid in a heat exchange relationship with another fluid (e.g., a refrigerant) in a heat exchanger (e.g., an evaporator) to absorb heat from the circulated fluid. The working fluid from the chiller 102 and/or the boiler 104 may be transported to the AHU 106 via piping 108.

The AHU 106 may place the working fluid in a heat exchange relationship with an airflow passing through the AHU 106 (e.g., via one or more stages of cooling coils and/or heating coils). The airflow may be, for example, outside air, return air from within the building 10, or a combination of both. The AHU 106 may transfer heat between the airflow and the working fluid to provide heating or cooling for the airflow. For example, the AHU 106 may include one or more fans or blowers configured to pass the airflow over or through a heat exchanger containing the working fluid. The working fluid may then return to the chiller 102 or the boiler 104 via piping 110.

The airside system 130 may deliver the airflow supplied by the AHU 106 (i.e., the supply airflow) to the building 10 via air supply ducts 112 and may provide return air from the building 10 to the AHU 106 via air return ducts 114. In some embodiments, the airside system 130 includes multiple variable air volume (VAV) units 116. For example, the airside system 130 is shown to include a separate VAV unit 116 on each floor or zone of the building 10. The VAV units 116 may include dampers or other flow control elements that can be operated to control an amount of the supply airflow provided to individual zones of the building 10. In other embodiments, the airside system 130 delivers the supply airflow into one or more zones of the building 10 (e.g., via supply the ducts 112) without using intermediate VAV units 116 or other flow control elements. The AHU 106 may include various sensors (e.g., temperature sensors, pressure sensors, etc.) configured to measure attributes of the supply airflow. The AHU 106 may receive input from sensors located within the AHU 106 and/or within the building zone and may adjust the flow rate, temperature, or other attributes of the supply airflow through the AHU 106 to achieve setpoint conditions for the building zone.

Referring now to FIG. 2, a schematic diagram of a waterside system 200 is shown, according to some exemplary embodiments of the present disclosure. In various embodiments, the waterside system 200 may supplement or replace the waterside system 120 in the HVAC&R system 100 or may be implemented separate from the HVAC&R system 100. When implemented in the HVAC&R system 100, the waterside system 200 may include a subset of the HVAC&R devices in the HVAC&R system 100 (e.g., the boiler 104, the chiller 102, pumps, valves, etc.) and may operate to supply a heated or chilled fluid to the AHU 106. The HVAC&R devices of the waterside system 200 may be located within the building 10 (e.g., as components of the waterside system 120) or at an offsite location such as a central plant.

In FIG. 2, the waterside system 200 is shown as a central plant having a plurality of sub-plants 202-212. The sub-plants 202-212 are shown to include a heater sub-plant 202, a heat recovery chiller sub-plant 204, a chiller sub-plant 206, a cooling tower sub-plant 208, a hot thermal energy storage (TES) sub-plant 210, and a cold thermal energy storage (TES) sub-plant 212. The sub-plants 202-212 consume resources (e.g., water, natural gas, electricity, etc.) from utilities to serve the thermal energy loads (e.g., hot water, cold water, heating, cooling, etc.) of a building or campus. For example, the heater sub-plant 202 may be configured to heat water in a hot water loop 214 that circulates the hot water between the heater sub-plant 202 and the building 10. The chiller sub-plant 206 may be configured to chill water in a cold water loop 216 that circulates the cold water between the chiller sub-plant 206 and the building 10. The heat recovery chiller sub-plant 204 may be configured to transfer heat from the cold water loop 216 to the hot water loop 214 to provide additional heating for the hot water and additional cooling for the cold water. A condenser water loop 218 may absorb heat from the cold water in the chiller sub-plant 206 and reject the absorbed heat in the cooling tower sub-plant 208 or transfer the absorbed heat to the hot water loop 214. The hot TES sub-plant 210 and the cold TES sub-plant 212 may store hot and cold thermal energy, respectively, for subsequent use.

The hot water loop 214 and the cold water loop 216 may deliver the heated and/or chilled water to air handlers located on the rooftop of the building 10 (e.g., the AHU 106) or to individual floors or zones of the building 10 (e.g., the VAV units 116). The air handlers push air past heat exchangers (e.g., heating coils or cooling coils) through which the water flows to provide heating or cooling for the air. The heated or cooled air may be delivered to individual zones of the building 10 to serve the thermal energy loads of the building 10. The water then returns to the sub-plants 202-212 to receive further heating or cooling.

Although the sub-plants 202-212 are shown and described as heating and cooling water for circulation to a building, it is understood that any other type of working fluid (e.g., glycol, CO2, etc.) may be used in place of or in addition to water to serve the thermal energy loads. In other embodiments, the sub-plants 202-212 may provide heating and/or cooling directly to the building or campus without requiring an intermediate heat transfer fluid. These and other variations to the waterside system 200 are within the teachings of the present invention.

Each of the sub-plants 202-212 may include a variety of equipment configured to facilitate the functions of the sub-plant. For example, the heater sub-plant 202 is shown to include a plurality of heating elements 220 (e.g., boilers, electric heaters, etc.) configured to add heat to the hot water in the hot water loop 214. The heater sub-plant 202 is also shown to include several pumps 222 and 224 configured to circulate the hot water in the hot water loop 214 and to control the flow rate of the hot water through individual heating elements 220. The chiller sub-plant 206 is shown to include a plurality of chillers 232 configured to remove heat from the cold water in the cold water loop 216. The chiller sub-plant 206 is also shown to include several pumps 234 and 236 configured to circulate the cold water in the cold water loop 216 and to control the flow rate of the cold water through individual chillers 232.

The heat recovery chiller sub-plant 204 is shown to include a plurality of heat recovery heat exchangers 226 (e.g., refrigeration circuits) configured to transfer heat from the cold water loop 216 to the hot water loop 214. The heat recovery chiller sub-plant 204 is also shown to include several pumps 228 and 230 configured to circulate the hot water and/or cold water through the heat recovery heat exchangers 226 and to control the flow rate of the water through individual heat recovery heat exchangers 226. The cooling tower sub-plant 208 is shown to include a plurality of cooling towers 238 configured to remove heat from the condenser water in the condenser water loop 218. The cooling tower sub-plant 208 is also shown to include several pumps 240 configured to circulate the condenser water in the condenser water loop 218 and to control the flow rate of the condenser water through individual cooling towers 238.

The hot TES sub-plant 210 is shown to include a hot TES tank 242 configured to store the hot water for later use. The hot TES sub-plant 210 may also include one or more pumps or valves configured to control the flow rate of the hot water into or out of the hot TES tank 242. The cold TES sub-plant 212 is shown to include cold TES tanks 244 configured to store the cold water for later use. The cold TES sub-plant 212 may also include one or more pumps or valves configured to control the flow rate of the cold water into or out of the cold TES tanks 244.

In some embodiments, one or more of the pumps in the waterside system 200 (e.g., pumps 222, 224, 228, 230, 234, 236, and/or 240) or pipelines in the waterside system 200 include an isolation valve associated therewith. Isolation valves may be integrated with the pumps or positioned upstream or downstream of the pumps to control the fluid flows in the waterside system 200. In various embodiments, the waterside system 200 may include more, fewer, or different types of devices and/or sub-plants based on the particular configuration of the waterside system 200 and the types of loads served by the waterside system 200.

Referring now to FIG. 3, a block diagram of an airside system 300 is shown, according to an exemplary embodiment. In various embodiments, the airside system 300 may supplement or replace the airside system 130 in the HVAC&R system 100 or may be implemented separate from the HVAC&R system 100. When implemented in the HVAC&R system 100, the airside system 300 may include a subset of the HVAC&R devices in the HVAC&R system 100 (e.g., the AHU 106, the VAV units 116, the ducts 112-114, fans, dampers, etc.) and may be located in or around the building 10. The airside system 300 may operate to heat or cool an airflow provided to the building 10 using a heated or chilled fluid provided by the waterside system 200.

In FIG. 3, the airside system 300 is shown to include an economizer-type air handling unit (AHU) 302. Economizer-type AHUs vary the amount of outside air and return air used by the air handling unit for heating or cooling. For example, the AHU 302 may receive return air 304 from a building zone 306 via a return air duct 308 and may deliver supply air 310 to the building zone 306 via a supply air duct 312. In some embodiments, the AHU 302 is a rooftop unit located on the roof of the building 10 (e.g., the AHU 106 as shown in FIG. 1) or otherwise positioned to receive both return air 304 and outside air 314. The AHU 302 may be configured to operate exhaust air damper 316, mixing damper 318, and outside air damper 320 to control an amount of outside air 314 and return air 304 that combine to form the supply air 310. Any return air 304 that does not pass through the mixing damper 318 may be exhausted from the AHU 302 through the exhaust damper 316 as exhaust air 322.

Each of the dampers 316-320 may be operated by an actuator. For example, the exhaust air damper 316 may be operated by an actuator 324, the mixing damper 318 may be operated by an actuator 326, and the outside air damper 320 may be operated by an actuator 328. The actuators 324-328 may communicate with an AHU controller 330 via a communications link 332. The actuators 324-328 may receive control signals from the AHU controller 330 and may provide feedback signals to the AHU controller 330. Feedback signals may include, for example, an indication of a current actuator or damper position, an amount of torque or force exerted by the actuator, diagnostic information (e.g., results of diagnostic tests performed by the actuators 324-328), status information, commissioning information, configuration settings, calibration data, and/or other types of information or data that may be collected, stored, or used by the actuators 324-328. The AHU controller 330 may be an economizer controller configured to use one or more control algorithms (e.g., state-based algorithms, extremum seeking control (ESC) algorithms, proportional-integral (PI) control algorithms, proportional-integral-derivative (PID) control algorithms, model predictive control (MPC) algorithms, feedback control algorithms, etc.) to control the actuators 324-328.

Still referring to FIG. 3, the AHU 302 is shown to include a cooling coil 334, a heating coil 336, and a fan 338 positioned within the supply air duct 312. The fan 338 may be configured to force the supply air 310 through the cooling coil 334 and/or the heating coil 336, and provide the supply air 310 to the building zone 306. The AHU controller 330 may communicate with the fan 338 via a communications link 340 to control a flow rate of the supply air 310. In some embodiments, the AHU controller 330 controls an amount of heating or cooling applied to the supply air 310 by modulating a speed of the fan 338.

The cooling coil 334 may receive a chilled fluid from the waterside system 200 (e.g., from the cold water loop 216) via piping 342 and may return the chilled fluid to the waterside system 200 via piping 344. Valve 346 may be positioned along the piping 342 or the piping 344 to control a flow rate of the chilled fluid through the cooling coil 334. In some embodiments, the cooling coil 334 includes multiple stages of cooling coils that can be independently activated and deactivated (e.g., by the AHU controller 330, by a BMS controller 366, etc.) to modulate an amount of cooling applied to the supply air 310.

The heating coil 336 may receive a heated fluid from the waterside system 200 (e.g., from the hot water loop 214) via piping 348 and may return the heated fluid to the waterside system 200 via piping 350. Valve 352 may be positioned along the piping 348 or the piping 350 to control a flow rate of the heated fluid through the heating coil 336. In some embodiments, the heating coil 336 includes multiple stages of heating coils that can be independently activated and deactivated (e.g., by the AHU controller 330, by the BMS controller 366, etc.) to modulate an amount of heating applied to the supply air 310.

Each of the valves 346 and 352 may be controlled by an actuator. For example, the valve 346 may be controlled by an actuator 354 and the valve 352 may be controlled by an actuator 356. The actuators 354-356 may communicate with the AHU controller 330 via communications links 358-360. The actuators 354-356 may receive control signals from the AHU controller 330 and may provide feedback signals to the AHU controller 330. In some embodiments, the AHU controller 330 receives a measurement of the supply air temperature from a temperature sensor 362 positioned in the supply air duct 312 (e.g., downstream of the cooling coil 334 and/or the heating coil 336). The AHU controller 330 may also receive a measurement of the temperature of the building zone 306 from a temperature sensor 364 located in the building zone 306.

In some embodiments, the AHU controller 330 operates the valves 346 and 352 via the actuators 354-356 to modulate an amount of heating or cooling provided to the supply air 310 (e.g., to achieve a setpoint temperature for the supply air 310 or to maintain the temperature of the supply air 310 within a setpoint temperature range). The positions of the valves 346 and 352 affect the amount of heating or cooling provided to the supply air 310 by the cooling coil 334 or the heating coil 336, and may correlate with the amount of energy consumed to achieve a desired supply air temperature. The AHU controller 330 may control the temperature of the supply air 310 and/or the building zone 306 by activating or deactivating the coils 334-336, adjusting a speed of the fan 338, or a combination of both.

Still referring to FIG. 3, the airside system 300 is shown to include the BMS controller 366 and a client device 368. The BMS controller 366 may include one or more computer systems (e.g., servers, supervisory controllers, subsystem controllers, etc.) that serve as system level controllers, application or data servers, head nodes, or master controllers for the airside system 300, the waterside system 200, the HVAC&R system 100, and/or other controllable systems that serve the building 10. The BMS controller 366 may communicate with multiple downstream building systems or subsystems (e.g., the HVAC&R system 100, a security system, a lighting system, the waterside system 200, etc.) via a communications link 370 according to like or disparate protocols (e.g., LON, BACnet, etc.). In various embodiments, the AHU controller 330 and the BMS controller 366 may be separate (as shown in FIG. 3) or integrated. In an integrated implementation, the AHU controller 330 may be a software module configured for execution by a processor of the BMS controller 366.

In some embodiments, the AHU controller 330 receives information from the BMS controller 366 (e.g., commands, setpoints, operating boundaries, etc.) and provides information to the BMS controller 366 (e.g., temperature measurements, valve or actuator positions, operating statuses, diagnostics, etc.). For example, the AHU controller 330 may provide the BMS controller 366 with temperature measurements from the temperature sensors 362-364, equipment on/off states, equipment operating capacities, and/or any other information that can be used by the BMS controller 366 to monitor or control a variable state or condition within the building zone 306.

The client device 368 may include one or more human-machine interfaces or client interfaces (e.g., graphical user interfaces, reporting interfaces, text-based computer interfaces, client-facing web services, web servers that provide pages to web clients, etc.) for controlling, viewing, or otherwise interacting with the HVAC&R system 100, its subsystems, and/or devices. The client device 368 may be a computer workstation, a client terminal, a remote or local interface, or any other type of user interface device. The client device 368 may be a stationary terminal or a mobile device. For example, the client device 368 may be a desktop computer, a computer server with a user interface, a laptop computer, a tablet, a smartphone, a PDA, or any other type of mobile or non-mobile device. The client device 368 may communicate with the BMS controller 366 and/or the AHU controller 330 via a communications link 372.

Referring now to FIG. 4, a block diagram of a building management system (BMS) 400 is shown, according to some exemplary embodiments of the present disclosure. The BMS 400 may be implemented in the building 10 to automatically monitor and control various building functions. The BMS 400 is shown to include the BMS controller 366 and a plurality of building subsystems 428. The building subsystems 428 are shown to include a building electrical subsystem 434, an information communication technology (ICT) subsystem 436, a security subsystem 438, a HVAC&R subsystem 440, a lighting subsystem 442, a lift/escalators subsystem 432, and a fire safety subsystem 430. In various embodiments, the building subsystems 428 can include fewer, additional, or alternative subsystems. For example, the building subsystems 428 may also or alternatively include a refrigeration subsystem, an advertising or signage subsystem, a cooking subsystem, a vending subsystem, a printer or copy service subsystem, or any other type of building subsystem that uses controllable equipment and/or sensors to monitor or control the building 10. In some embodiments, the building subsystems 428 include the waterside system 200 and/or the airside system 300, as described with reference to FIGS. 2-3.

Each of the building subsystems 428 may include any number of devices, controllers, and connections for completing its individual functions and control activities. The HVAC&R subsystem 440 may include many of the same components as HVAC&R system 100, as described with reference to FIGS. 1-3. For example, the HVAC&R subsystem 440 may include and number of chillers, heaters, handling units, economizers, field controllers, supervisory controllers, actuators, temperature sensors, and/or other devices for controlling the temperature, humidity, airflow, or other variable conditions within the building 10. The lighting subsystem 442 may include any number of light fixtures, ballasts, lighting sensors, dimmers, or other devices configured to controllably adjust the amount of light provided to a building space. The security subsystem 438 may include occupancy sensors, video surveillance cameras, digital video recorders, video processing servers, intrusion detection devices, access control devices and servers, or other security-related devices.

Still referring to FIG. 4, the BMS controller 366 is shown to include a communications interface 407 and a BMS interface 409. The interface 407 may facilitate communications between the BMS controller 366 and external applications (e.g., monitoring and reporting applications 422, enterprise control applications 426, remote systems and applications 444, applications residing on client devices 448, etc.) for allowing user control, monitoring, and adjustment to the BMS controller 366 and/or the subsystems 428. The interface 407 may also facilitate communications between the BMS controller 366 and the client devices 448. The BMS interface 409 may facilitate communications between the BMS controller 366 and the building subsystems 428 (e.g., HVAC, lighting security, lifts, power distribution, business, etc.).

The interfaces 407, 409 can be or include wired or wireless communications interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wire terminals, etc.) for conducting data communications with the building subsystems 428 or other external systems or devices. In various embodiments, communications via the interfaces 407, 409 may be direct (e.g., local wired or wireless communications) or via a communications network 446 (e.g., a WAN, the Internet, a cellular network, etc.). For example, the interfaces 407, 409 can include an Ethernet card and port for sending and receiving data via an Ethernet-based communications link or network. In another example, the interfaces 407, 409 can include a WiFi transceiver for communicating via a wireless communications network. In another example, one or both of the interfaces 407, 409 may include cellular or mobile phone communications transceivers. In one embodiment, the communications interface 407 is a power line communications interface and the BMS interface 409 is an Ethernet interface. In other embodiments, both communications the interface 407 and the BMS interface 409 are Ethernet interfaces or are the same Ethernet interface.

Still referring to FIG. 4, the BMS controller 366 is shown to include a processing circuit 404 including a processor 406 and memory 408. The processing circuit 404 may be communicably connected to the BMS interface 409 and/or the communications interface 407 such that the processing circuit 404 and the various components thereof can send and receive data via the interfaces 407, 409. The processor 406 can be implemented as a general purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable electronic processing components.

The memory 408 (e.g., memory, memory unit, storage device, etc.) may include one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for storing data and/or computer code for completing or facilitating the various processes, layers and modules described in the present application. The memory 408 may be or include volatile memory or non-volatile memory. The memory 408 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present application. According to an exemplary embodiment, the memory 408 is communicably connected to the processor 406 via the processing circuit 404 and includes computer code for executing (e.g., by the processing circuit 404 and/or the processor 406) one or more processes described herein.

In some embodiments, the BMS controller 366 is implemented within a single computer (e.g., one server, one housing, etc.). In various other embodiments, the BMS controller 366 may be distributed across multiple servers or computers (e.g., that can exist in distributed locations). Further, while FIG. 4 shows the applications 422 and 426 as existing outside of the BMS controller 366, in some embodiments, the applications 422 and 426 may be hosted within the BMS controller 366 (e.g., within the memory 408).

Still referring to FIG. 4, the memory 408 is shown to include an enterprise integration layer 410, an automated measurement and validation (AM&V) layer 412, a demand response (DR) layer 414, a fault detection and diagnostics (FDD) layer 416, an integrated control layer 418, and a building subsystem integration later 420. The layers 410-420 may be configured to receive inputs from the building subsystems 428 and other data sources, determine optimal control actions for the building subsystems 428 based on the inputs, generate control signals based on the optimal control actions, and provide the generated control signals to the building subsystems 428. The following paragraphs describe some of the general functions performed by each of the layers 410-420 in the BMS 400.

The enterprise integration layer 410 may be configured to serve clients or local applications with information and services to support a variety of enterprise-level applications. For example, the enterprise control applications 426 may be configured to provide subsystem-spanning control to a graphical user interface (GUI) or to any number of enterprise-level business applications (e.g., accounting systems, user identification systems, etc.). The enterprise control applications 426 may also or alternatively be configured to provide configuration GUIs for configuring the BMS controller 366. In yet other embodiments, the enterprise control applications 426 can work with the layers 410-420 to optimize building performance (e.g., efficiency, energy use, comfort, or safety) based on inputs received at the interface 407 and/or the BMS interface 409.

The building subsystem integration layer 420 may be configured to manage communications between the BMS controller 366 and the building subsystems 428. For example, the building subsystem integration layer 420 may receive sensor data and input signals from the building subsystems 428 and provide output data and control signals to the building subsystems 428. The building subsystem integration layer 420 may also be configured to manage communications between the building subsystems 428. The building subsystem integration layer 420 translate communications (e.g., sensor data, input signals, output signals, etc.) across a plurality of multi-vendor/multi-protocol systems.

The demand response layer 414 may be configured to optimize resource usage (e.g., electricity use, natural gas use, water use, etc.) and/or the monetary cost of such resource usage in response to satisfy the demand of the building 10. The optimization may be based on time-of-use prices, curtailment signals, energy availability, or other data received from utility providers, distributed energy generation systems 424, from energy storage 427 (e.g., the hot TES 242, the cold TES 244, etc.), or from other sources. The demand response layer 414 may receive inputs from other layers of the BMS controller 366 (e.g., the building subsystem integration layer 420, the integrated control layer 418, etc.). The inputs received from other layers may include environmental or sensor inputs such as temperature, carbon dioxide levels, relative humidity levels, air quality sensor outputs, occupancy sensor outputs, room schedules, and the like. The inputs may also include inputs such as electrical use (e.g., expressed in kWh), thermal load measurements, pricing information, projected pricing, smoothed pricing, curtailment signals from utilities, and the like.

According to an exemplary embodiment, the demand response layer 414 includes control logic for responding to the data and signals it receives. These responses can include communicating with the control algorithms in the integrated control layer 418, changing control strategies, changing setpoints, or activating/deactivating building equipment or subsystems in a controlled manner. The demand response layer 414 may also include control logic configured to determine when to utilize stored energy. For example, the demand response layer 414 may determine to begin using energy from the energy storage 427 just prior to the beginning of a peak use hour.

In some embodiments, the demand response layer 414 includes a control module configured to actively initiate control actions (e.g., automatically changing setpoints) which minimize energy costs based on one or more inputs representative of or based on demand (e.g., price, a curtailment signal, a demand level, etc.). In some embodiments, the demand response layer 414 uses equipment models to determine an optimal set of control actions. The equipment models may include, for example, thermodynamic models describing the inputs, outputs, and/or functions performed by various sets of building equipment. Equipment models may represent collections of building equipment (e.g., sub-plants, chiller arrays, etc.) or individual devices (e.g., individual chillers, heaters, pumps, etc.).

The demand response layer 414 may further include or draw upon one or more demand response policy definitions (e.g., databases, XML, files, etc.). The policy definitions may be edited or adjusted by a user (e.g., via a graphical user interface) so that the control actions initiated in response to demand inputs may be tailored for the user's application, desired comfort level, particular building equipment, or based on other concerns. For example, the demand response policy definitions can specify which equipment may be turned on or off in response to particular demand inputs, how long a system or piece of equipment should be turned off, what setpoints can be changed, what the allowable set point adjustment range is, how long to hold a high demand setpoint before returning to a normally scheduled setpoint, how close to approach capacity limits, which equipment modes to utilize, the energy transfer rates (e.g., the maximum rate, an alarm rate, other rate boundary information, etc.) into and out of energy storage devices (e.g., thermal storage tanks, battery banks, etc.), and when to dispatch on-site generation of energy (e.g., via fuel cells, a motor generator set, etc.).

The integrated control layer 418 may be configured to use the data input or output of the building subsystem integration layer 420 and/or the demand response later 414 to make control decisions. Due to the subsystem integration provided by the building subsystem integration layer 420, the integrated control layer 418 can integrate control activities of the subsystems 428 such that the subsystems 428 behave as a single integrated supersystem. In an exemplary embodiment, the integrated control layer 418 includes control logic that uses inputs and outputs from a plurality of building subsystems to provide greater comfort and energy savings relative to the comfort and energy savings that separate subsystems could provide alone. For example, the integrated control layer 418 may be configured to use an input from a first subsystem to make an energy-saving control decision for a second subsystem. Results of these decisions can be communicated back to the building subsystem integration layer 420.

The integrated control layer 418 is shown to be logically below the demand response layer 414. The integrated control layer 418 may be configured to enhance the effectiveness of the demand response layer 414 by enabling the building subsystems 428 and their respective control loops to be controlled in coordination with the demand response layer 414. This configuration may advantageously reduce disruptive demand response behavior relative to conventional systems. For example, the integrated control layer 418 may be configured to assure that a demand response-driven upward adjustment to the setpoint for chilled water temperature (or another component that directly or indirectly affects temperature) does not result in an increase in fan energy (or other energy used to cool a space) that would result in greater total building energy use than was saved at the chiller.

The integrated control layer 418 may be configured to provide feedback to the demand response layer 414 so that the demand response layer 414 checks that constraints (e.g., temperature, lighting levels, etc.) are properly maintained even while demanded load shedding is in progress. The constraints may also include setpoint or sensed boundaries relating to safety, equipment operating limits and performance, comfort, fire codes, electrical codes, energy codes, and the like. The integrated control layer 418 is also logically below the fault detection and diagnostics layer 416 and the automated measurement and validation layer 412. The integrated control layer 418 may be configured to provide calculated inputs (e.g., aggregations) to these higher levels based on outputs from more than one building subsystem.

The automated measurement and validation (AM&V) layer 412 may be configured to verify that control strategies commanded by the integrated control layer 418 or the demand response layer 414 are working properly (e.g., using data aggregated by the AM&V layer 412, the integrated control layer 418, the building subsystem integration layer 420, the FDD layer 416, or otherwise). The calculations made by the AM&V layer 412 may be based on building system energy models and/or equipment models for individual BMS devices or subsystems. For example, the AM&V layer 412 may compare a model-predicted output with an actual output from the building subsystems 428 to determine an accuracy of the model.

The fault detection and diagnostics (FDD) layer 416 may be configured to provide on-going fault detection for the building subsystems 428, building subsystem devices (i.e., building equipment), and control algorithms used by the demand response layer 414 and the integrated control layer 418. The FDD layer 416 may receive data inputs from the integrated control layer 418, directly from one or more building subsystems or devices, or from another data source. The FDD layer 416 may automatically diagnose and respond to detected faults. The responses to detected or diagnosed faults may include providing an alert message to a user, a maintenance scheduling system, or a control algorithm configured to attempt to repair the fault or to work-around the fault.

The FDD layer 416 may be configured to output a specific identification of the faulty component or cause of the fault (e.g., loose damper linkage) using detailed subsystem inputs available at the building subsystem integration layer 420. In other exemplary embodiments, the FDD layer 416 is configured to provide “fault” events to the integrated control layer 418 which executes control strategies and policies in response to the received fault events. According to an exemplary embodiment, the FDD layer 416 (or a policy executed by an integrated control engine or business rules engine) may shut-down systems or direct control activities around faulty devices or systems to reduce energy waste, extend equipment life, or assure proper control response.

The FDD layer 416 may be configured to store or access a variety of different system data stores (or data points for live data). The FDD layer 416 may use some content of the data stores to identify faults at the equipment level (e.g., specific chiller, specific AHU, specific terminal unit, etc.) and other content to identify faults at component or subsystem levels. For example, the building subsystems 428 may generate temporal (i.e., time-series) data indicating the performance of the BMS 400 and the various components thereof. The data generated by the building subsystems 428 may include measured or calculated values that exhibit statistical characteristics and provide information about how the corresponding system or process (e.g., a temperature control process, a flow control process, etc.) is performing in terms of error from its setpoint. These processes can be examined by the FDD layer 416 to expose when the system begins to degrade in performance and alert a user to repair the fault before it becomes more severe.

Actuator

Referring now to FIGS. 5-7, drawings of an actuator 500 for use in a building system (e.g., an HVAC&R or fire safety system) is shown, according to some exemplary embodiments. In some implementations, the actuator 500 may be used in the HVAC&R system 100, the waterside system 200, the airside system 300, or the BMS 400, as described with reference to FIGS. 1-4. For example, the actuator 500 may be a damper actuator, a valve actuator, a fan actuator, a pump actuator, or any other type of actuator that can be used in an HVAC&R system or BMS.

The actuator 500 is shown to include a housing 502 having a front side 504 (i.e., side A), a rear side 506 (i.e., side B) opposite the front side 504, and a bottom 508. The housing 502 may contain mechanical and processing components of the actuator 500. In some embodiments, the housing 502 may contain a brushless direct current (BLDC) motor and a processing circuit configured to provide a pulse width modulated (PWM) DC output to control the speed of the BLDC motor. The processing circuit may be configured to compare a representation of the electric current output to the BLDC motor to a threshold and may hold the PWM DC output in an off state when the current exceeds the threshold. In some embodiments, the processing circuit is configured to set the PWM DC output to zero and then ramp up the PWM DC output when the actuator 500 approaches an end stop. In some embodiments, the processing circuit is coupled to one or more position sensors configured to measure a position of the actuator 500. The internal components of the actuator 500 are described in greater detail with reference to FIGS. 8A-11.

The actuator 500 is shown to include a drive device 510. The drive device 510 may be a drive mechanism, a hub, or other device configured to drive or effectuate movement of an HVAC&R system component. For example, the drive device 510 may be configured to receive a shaft of a damper, a valve, or any other movable HVAC&R system component in order to drive (e.g., rotate) the shaft. In some embodiments, the actuator 500 includes a coupling device 512 configured to aid in coupling the drive device 510 to the movable HVAC&R system component. For example, the coupling device 512 may facilitate attaching the drive device 510 to a valve or damper shaft.

The actuator 500 is shown to include an input connection 520 and an output connection 522. In some embodiments, the input connection 520 and the output connection 522 are located along the bottom 508. In other embodiments, the input connection 520 and the output connection 522 may be located along one or more other surfaces of the housing 502. The input connection 520 may be configured to receive a control signal (e.g., a voltage input signal) from an external system or device. The actuator 500 may use the control signal to determine an appropriate PWM DC output for the BLDC motor. The output connection 522 may be configured to provide a feedback signal to a controller of the HVAC&R system or BMS in which the actuator 500 is implemented (e.g., an AHU controller, an economizer controller, a supervisory controller, a zone controller, a field controller, an enterprise level controller, etc.). The feedback signal may indicate the rotational position and/or speed of the actuator 500.

Still referring to FIGS. 5-7, the actuator 500 is shown to include a first user-operable switch 514 located along the front side 504 (shown in FIG. 6) and a second user-operable switch 516 located along the rear side 506 (shown in FIG. 7). The switches 514-516 may be potentiometers or any other type of switch (e.g., push button switches such as switch 515, dials, flippable switches, etc.). The switches 514-516 may be used to set the actuator 500 to a particular operating mode or to configure the actuator 500 to accept a particular type of input. However, it should be understood that the switches 514-516 are optional components and are not required for the actuator 500 to perform the processes described herein. As such, one or more of switches 514-516 may be omitted without departing from the teachings of the present invention.

In some embodiments, the housing 502 may have a different overall shape than that shown in FIGS. 5-7.

Referring particularly to FIG. 6, the switch 514 may be a mode selection switch having a distinct number of modes or positions. The switch 514 may be provided for embodiments in which the actuator 500 is a linear proportional actuator that controls the position of the drive device 510 as a function of a DC input voltage received at the input connection 520. For example, the position of the mode selection switch 514 may be adjusted to set the actuator 500 to operate in a direct acting mode, a reverse acting mode, or a calibration mode.

The mode selection switch 514 is shown to include a 0-10 direct acting (DA) mode, a 2-10 DA mode, a calibration (CAL) mode, a 2-10 reverse acting (RA) mode, and a 0-10 RA mode. According to other exemplary embodiments, the mode selection switch 514 may have a greater or smaller number of modes and/or may have modes other than listed as above. The position of the mode selection switch 514 may define the range of DC input voltages that correspond to the rotational range of the drive device 510. For example, when the mode selection switch 514 is set to 0-10 DA, an input voltage of 0.0 VDC may correspond to 0 degrees of rotation position for drive device 510. For this same mode, an input voltage of 1.7 VDC may correspond to 15 degrees of rotation position, 3.3 VDC may correspond to 30 degrees of rotation position, 5.0 VDC may correspond to 45 degrees of rotation position, 6.7 VDC may correspond to 60 degrees of rotation position, 8.3 VDC may correspond to 75 degrees of rotation position, and 10.0 VDC may correspond to 90 degrees of rotation position. It should be understood that these voltages and corresponding rotational positions are merely exemplary and may be different in various implementations.

Referring particularly to FIG. 7, the switch 516 may be a mode selection switch having a distinct number or modes or positions. The switch 516 may be provided for embodiments in which the actuator 500 is configured to accept an AC voltage at the input connection 520. For example, the position of the switch 516 may be adjusted to set the actuator 500 to accept various different AC voltages at the input connection 520.

The mode selection switch 516 is shown to include a “24 VAC” position, a “120 VAC” position, a “230 VAC” position, an “Auto” position. Each position of the switch 516 may correspond to a different operating mode. According to other exemplary embodiments, the switch 516 may have a greater or lesser number of positions and/or may have modes other than the modes explicitly listed. The different operating modes indicated by the switch 516 may correspond to different voltage reduction factors applied to the input voltage received at input connection 520. For example, with the switch 516 in the 24 VAC position, the actuator 500 may be configured to accept an input voltage of approximately 24 VAC (e.g., 20-30 VAC) at the input connection 520 and may apply a reduction factor of approximately 1 to the input voltage. With the switch 516 in the 120 VAC position, the actuator 500 may be configured to accept an input voltage of approximately 120 VAC (e.g., 100-140 VAC, 110-130 VAC, etc.) at the input connection 520 and may apply a reduction factor of approximately 5 (e.g., 3-7, 4-6, 4.5-5.5, etc.) to the input voltage. With the switch 516 in the 230 VAC position, the actuator 500 may be configured to accept an input voltage of approximately 230 VAC (e.g., 200-260 VAC, 220-240 VAC, etc.) at the input connection 520 and may apply a reduction factor of approximately 9.6 (e.g., 7-13, 8-12, 9-10, etc.) to the input voltage. With the switch 516 in the “Auto” position, the actuator 500 may be configured automatically determine the input voltage received at the input connection 520 and may adjust the voltage reduction factor accordingly.

The actuator 500 shown in FIGS. 5-7 may be a modular actuator that supports modular interfacing with different types of fail-safe assemblies as described in greater detail with reference to FIGS. 8A-11.

Modular Actuator

Referring now to FIGS. 8A-8C, block diagrams of a modular actuator system for use in an HVAC&R system are shown, according to some exemplary embodiments of the present disclosure. In some implementations, the modular actuator system shown in FIGS. 8A-8C may be used in the HVAC&R system 100, the waterside system 200, the airside system 300, or the BMS 400, as described with reference to FIGS. 1-4. For example, the actuators 324-328, 354-356, 500 may be implemented using the modular actuator system shown in FIGS. 8A-8C. The modular actuator system may include an actuator 800 and one or more fail-safe assemblies. In some embodiments, the one or more fail-safe assemblies may include a spring return fail-safe assembly 801A shown in FIG. 8B and an energy storage return fail-safe assembly 801B shown in FIG. 8C.

In some embodiments, the actuator 800 is a non-fail-safe actuator which supports modular interfacing with the one or more fail-safe assemblies (for example, the spring return fail-safe assembly 801A and the energy storage return fail-safe assembly 801B), one at a time. In some embodiments, the one or more fail-safe assemblies are provided as modular attachments that can be removably coupled to the actuator 800 as per application requirement. For example, when a non-fail-safe functionality is required, the actuator 800 can be used without being coupled to any of the fail-safe assemblies 801A and 801B. However, when a fail-safe functionality is required, the actuator 800 may be removably coupled to one of the fail-safe assemblies 801A and 801B that meets the application requirements. Upon being removably coupled to one of the fail-safe assemblies 801A and 801B, the actuator 800 functions as a fail-safe actuator.

Referring particularly to FIG. 8A, the actuator 800 is shown to have been coupled to a movable component 802. For example, the actuator 800 may be a damper actuator, a valve actuator, a fan actuator, a pump actuator, or any other type of actuator that can be used in an HVAC&R system or BMS.

In some embodiments, the movable component 802 may be any type of control device configured to control an environmental parameter in an HVAC&R system, including a 2-way or 3-way two position electric motorized valve, a ball isolation valve, a floating point control valve, an adjustable flow control device, or a modulating control valve. In some embodiments, the movable component 802 may regulate the flow of fluid through a conduit, pipe, or tube (e.g., conduit 804) in a waterside system (e.g., the waterside system 200, shown in FIG. 2). In other embodiments, the movable component 802 may regulate the flow of air through a duct (e.g., a duct 804) in an airside system (e.g., the airside system 300, shown in FIG. 3).

The actuator 800 is shown to include a first housing 806 having a base portion 808 and a top cover portion 810. The top cover portion 810 is removably coupled to the base portion 808 to conceal an opening of the base portion 808. Along a top edge 812 of the base portion 808, which contacts the top cover portion 810, a seal member 814 is provided for ingress protection. In some examples, the seal member 814 is an O-ring integrated along the top edge 812. The O-ring may be made from a weather resistant material, for example, silicon or rubber. The seal member 814 may ensure a tight and reliable seal against the top cover portion 810, thus preventing any external elements (for example, water) from entering the first housing 806.

The top cover portion 810 may include a first engagement mechanism 816 that enables the top cover portion 810 to be removably attached to the base portion 808. The first engagement mechanism 816 may include one or more clips, latches, snap mechanism, screws, etc. The first engagement mechanism 816 may hold the top cover portion 810 securely in place, when the top cover portion 810 is attached to the base portion 808. The top cover portion 810 may further include a grip mechanism (not shown) that allows a user/an operator to hold the top cover portion 810 while removing the top cover portion 810 from the base portion 808 or while placing the top cover portion 810 on the base portion 808. The first engagement mechanism 816 and the grip mechanism enable easy removal and placement of the top cover portion 810 without requiring any specialized tool. In other words, the first housing 806 includes the base portion 808 with an O-ring equipped top edge 812 and the top cover portion 810 which removably fits onto the top edge 812, forming a secure seal via the seal member 814.

The base portion 808 may further include a modular interface 818 that can couple with the first engagement mechanism 816, allowing easy removal or attachment of the top cover portion 810 with the base portion 808. For example, when the first engagement mechanism 816 is snap fit mechanism, the modular interface 818 when pressed may enable release of the snap fit mechanism.

The base portion 808 may house (or contain) various mechanical, electronics, and processing components of the actuator 800. In some embodiments, the base portion 808 may house therein a motor 820, a drive device 822, processing circuitry 824, and one or more spring-loaded electrical connectors 826.

In some embodiments, the motor 820 may be a brushless direct current (BLDC) motor. The drive device 822 may be a drive mechanism coupled to the motor 820 at one side and the movable component 802 on the other side. The drive device 822 may be driven by the motor 820 for driving or effectuating a movement of the movable component 802. The drive device 822, in FIG. 8A, is shown to include a gear train 828 coupled to the motor 820 and a hub 830 coupled to the gear train 828 and the movable component 802. The hub 830 may serve or function as a coupling device configured to aid in coupling the gear train 828 to the movable component 802. In an example, the hub 830 may facilitate attaching the gear train 828 to a valve or damper shaft.

The motor 820 and/or the drive device 822 may be coupled with one or more position sensors (not shown). Examples of the position sensors may include, but are not limited to, Hall effect sensors, potentiometers, optical sensors, inductive sensors, or other types of sensors configured to measure rotational position of the motor 820 and/or the drive device 822. The position sensors may be configured to provide position signals to the processing circuitry 824.

The processing circuitry 824 may be communicably coupled to the motor 820. The processing circuitry 824 may include a processor (not shown), a memory (not shown), and communication circuit (not shown). The processor can be a general purpose or specific purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable processing components. The processor may be configured to execute computer code or instructions stored in the memory or received from other computer readable media (e.g., CDROM, network storage, a remote server, etc.).

The memory may include one or more devices (e.g., memory units, memory devices, storage devices, etc.) for storing data and/or computer code for completing and/or facilitating the various processes described in the present disclosure. The memory may include random access memory (RAM), read-only memory (ROM), hard drive storage, temporary storage, non-volatile memory, flash memory, optical memory, or any other suitable memory for storing software objects and/or computer instructions. The memory may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present disclosure. The memory may be communicably connected to the processor and may include computer code for executing (e.g., by the processor) one or more processes described herein.

The communication circuit may be a wired or wireless communications link and may use any of a variety of disparate communications protocols (e.g., BACnet, LON, WiFi, Bluetooth, NFC, TCP/IP, etc.). In some embodiments, the communication circuit may be an integrated circuit, chip, or microcontroller unit (MCU) configured to bridge the actuator 800 and external systems or devices. In some embodiments, the communication circuit is the Johnson Controls BACnet on a Chip (JBOC) product. For example, the communication circuit may be a pre-certified BACnet communication module capable of communicating on a building automation and controls network (BACnet) using a master/slave token passing (MSTP) protocol. The communication circuit may be added to any existing product to enable BACnet communication with minimal software and hardware design effort. In other words, the communication circuit may provide a BACnet interface for the actuator 800.

The communication circuit may also be configured to support data communications within the actuator 800. In some embodiments, the communication circuit may receive internal actuator data from the processor. For example, the internal actuator data may include sensed motor current, a measured or calculated motor torque, motor speed, motor position, configuration parameters, forward and reverse stroke length parameters, equipment model data, firmware versions, software versions, time series data, a total distance traveled, an amount of time required to open/close the movable component 802 (e.g., a valve), or any other type of data used or stored internally within the actuator 800. In some embodiments, the communication circuit may transmit external data to the processor. The external data may include, for example, position setpoints, speed setpoints, control signals, configuration parameters, end stop locations, forward and reverse stroke length parameters, equipment model data, actuator firmware, actuator software, or any other type of data which can be used by the actuator 800 to operate the motor 820 and/or the drive device 822.

The processing circuitry 824 may be configured to receive a control signal indicating control data (e.g., position setpoints, speed setpoints, etc.) for the motor 820. The processing circuitry 824 may be further configured to receive the position signals from the position sensors coupled to the motor 820 and/or the drive device 822. The processing circuitry 824 may determine a position of the motor 820 and/or the drive device 822 based on the position signals and determine whether to operate the motor 820. For example, the processing circuitry 824 may compare a current position of the drive device 822 with a position setpoint received via the control signal and may operate the motor 820 (e.g., control a speed of the motor 820) to achieve the position setpoint. To control the speed of the motor 820 in accordance with the control signal, the processing circuitry 824 may provide a signal output to the motor 820. In an example, the signal output may be a PWM voltage output. A duty cycle of the PWM voltage output may define a rotational speed of the motor 820. The processing circuitry 824 may increase the duty cycle of the PWM voltage output to increase the speed of motor 820 and may decrease the duty cycle of the PWM voltage output to decrease the speed of motor 820.

The actuator 800 may further include an input connection 832 and an output connection 834. In some embodiments, the input connection 832 and the output connection 834 may be located along a bottom of the base portion 808. In other embodiments, the input connection 832 and the output connection 834 may be located along one or more other surfaces of the base portion 808. The input connection 832 may be configured to receive the control signal (e.g., a voltage input signal), for example, from an external system or device. The processing circuitry 824 may use the control signal to determine an appropriate signal output for controlling the motor 820, and in turn driving the drive device 822. In some embodiments, the control signal may be received from a controller such as an AHU controller (e.g., the AHU controller 330 shown in FIG. 3), an economizer controller, a supervisory controller (e.g., the BMS controller 366 shown in FIG. 3), a zone controller, a field controller, an enterprise level controller, a motor controller, an equipment-level controller (e.g., an actuator controller), or any other type of controller that can be used in an HVAC&R system or BMS.

In some embodiments, the control signal may be a DC voltage signal. The processing circuitry 824 may be configured to control the position of the drive device 822 according to the value of the DC voltage received at the input connection 832. For example, a minimum input voltage (e.g., 0.0 VDC) may correspond to a minimum rotational position of the drive device 822 (e.g., 0 degrees, −5 degrees, etc.), whereas a maximum input voltage (e.g., 10.0 VDC) may correspond to a maximum rotational position of the drive device 822 (e.g., 90 degrees, 95 degrees, etc.). Input voltages between the minimum and maximum input voltages may cause the processing circuitry 824 to move the drive device 822 into an intermediate position between the minimum rotational position and the maximum rotational position. In other embodiments, the processing circuitry 824 may use different input voltage ranges or a different type of input signal (e.g., AC voltage or current) to control the position and/or rotational speed of the drive device 822.

In some other embodiments, the control signal may be an AC voltage signal. The input connection 832 may be configured to receive an AC voltage signal having a standard power line voltage (e.g., 120 VAC or 230 VAC at 50/60 Hz). The frequency of the voltage signal may be modulated by the processing circuitry 824 to adjust the rotational position and/or speed of the drive device 822. In some embodiments, the processing circuitry 824 may use the voltage signal to power various components of the actuator 800, e.g., the motor 820. The processing circuitry 824 may use the AC voltage signal received via the input connection 832 as a control signal, a source of electric power, or both. In some embodiments, the voltage signal is received at the input connection 832 from a power supply line that provides an AC voltage having a constant or substantially constant frequency (e.g., 120 VAC or 230 VAC at 50 Hz or 60 Hz). The input connection 832 may include one or more data connections (separate from the power supply line) through which the processing circuitry 824 receives control signals from a controller or another actuator (e.g., 0-10 VDC control signals).

In some embodiments, the control signal may be received at the input connection 832 from another actuator. For example, if multiple actuators are interconnected in a tandem arrangement, the input connection 832 may be connected (e.g., via a communications bus) to the output data connection of another actuator. One of the actuators may be arranged as a master actuator with its input connection 832 connected to a controller, whereas the other actuators may be arranged as slave actuators with their respective input connections connected to the output connection 834 of the master actuator.

The output connection 834 may be configured to provide a feedback signal to a controller of the HVAC&R system or BMS in which the actuator 800 is implemented (e.g., an AHU controller, an economizer controller, a supervisory controller, a zone controller, a field controller, an enterprise level controller, etc.). The feedback signal may indicate the rotational position and/or speed of the actuator 800. In some embodiments, the output connection 834 may be configured to provide a control signal to another actuator (e.g., a slave actuator) arranged in tandem with the actuator 800. The input connection 832 and the output connection 834 may be connected to the controller or the other actuator via a communications bus. The communications bus may be a wired or wireless communications link and may use any of a variety of disparate communications protocols (e.g., BACnet, LON, WiFi, Bluetooth, NFC, TCP/IP, etc.).

The one or more spring-loaded electrical connectors 826 (also referred to as pogo pins 826) provided in the base portion 808 are coupled to the motor 820 at one end. Other ends of the spring-loaded electrical connectors 826 are set free to make conductive contacts with other electrical components. In some embodiments, each spring-loaded electrical connector 826 may include a plunger housing containing a plunger mechanism equipped with a spring. The spring provides the force for the plunger mechanism to move between a depressed state and an extended state. For example, when pressure is applied to the top of the plunger, the spring gets compressed. The compression in the spring causes the plunger to move downwards into the plunger housing, creating the depressed state. When no pressure is applied from the top of the plunger, the spring relaxes and the plunger extends outwards from the plunger housing, creating the extended state. In the extended state, the spring-loaded electrical connectors 826 may make conductive contact with the other electrical components.

In some embodiments, when the top cover portion 810 is removably coupled to the base portion 808, the top cover portion 810 exerts pressure on the spring-loaded electrical connectors 826. Thus, the spring-loaded electrical connectors 826 are held in the depressed state (as shown in FIG. 8A) and do not make any conductive contact with the top cover portion 810. As and when the top cover portion 810 is removed or detached from the base portion 808, the pressure on the spring-loaded electrical connectors 826 is relieved, causing the spring-loaded electrical connectors 826 to extend out or protrude from the base portion 808 (as shown in FIG. 9).

When a non-fail-safe functionality is required from the actuator 800, the top cover portion 810 is attached to the base portion 808. However, when a fail-safe functionality is required, the top cover portion 810 is removed from the base portion 808 and one of the fail-safe assemblies 801A and 801B, shown in FIGS. 8B and 8C, that meets the application requirements is removably interfaced or coupled with the actuator 800.

The processing circuitry 824 may be further configured to determine which fail-safe assembly from the spring return fail-safe assembly 801A or the energy storage return fail-safe assembly 801B (e.g., a plurality of fail-safe assemblies) is removably coupled to the base portion 808. In some embodiments, the processing circuitry 824 may determine which fail-safe assembly is removably coupled to the base portion 808 based on whether the spring-loaded electrical connectors 826 have made a conductive contact with the removably coupled fail-safe assembly. Alternatively, or additionally, the processing circuitry 824 may determine which fail-safe assembly is removably coupled to the base portion 808 based on power or torque consumed in each cycle. For example, the actuator 800 when coupled with the spring return fail-safe assembly 801A may require more power as compared to when the actuator 800 is coupled with the energy storage return fail-safe assembly 801B or with the top cover portion 810 to overcome spring resistance of the spring return fail-safe assembly 801A.

In some embodiments, the actuator 800 and the movable component 802 may be packaged as separate devices. In some other embodiments, the actuator 800 and the movable component 802 may be provided within a common integrated device chassis or housing. In other words, the actuator 800 and the movable component 802 may not be packaged as separate devices, but as a single device. Reducing the number of devices in an HVAC&R system may provide numerous advantages, most notably in time and cost savings during the installation process. Because it is not necessary to install the actuator 800 and the movable component 802 as separate devices and then make a connection between them, technicians performing the installation may require less specialized training and fewer tools. Other advantages of a single device may include simplification of control and troubleshooting functions.

Referring particularly to FIG. 8B, the spring return fail-safe assembly 801A is shown. The spring return fail-safe assembly 801A includes a second housing 836 having a second engagement mechanism 838. The second engagement mechanism 838 may include one or more clips, latches, snap mechanism, screws, etc. which enable the spring return fail-safe assembly 801A to be removably coupled to the base portion 808 of the actuator 800, once the top cover portion 810 is removed from the base portion 808. The second engagement mechanism 838 may couple with the modular interface 818 of the actuator 800, allowing easy removal or attachment of the spring return fail-safe assembly 801A from/with the base portion 808. The second engagement mechanism 838 may hold the spring return fail-safe assembly 801A securely in place, when the spring return fail-safe assembly 801A is attached to the base portion 808. The spring return fail-safe assembly 801A may further include a grip mechanism (not shown) that allows a user/an operator to hold the spring return fail-safe assembly 801A while removing the spring return fail-safe assembly 801A from the base portion 808 or while placing the spring return fail-safe assembly 801A on the base portion 808. The second engagement mechanism 838 and the grip mechanism enable easy removal and placement of the spring return fail-safe assembly 801A from/on the actuator 800 without requiring any specialized tool.

The spring return fail-safe assembly 801A may further include one or more springs (e.g., a first spring 840A and a second spring 840B) and a spring arbor 842. The first spring 840A and the second spring 840B may function as a return mechanism and may be housed within the second housing 836 such that one end of each of the first spring 840A and the second spring 840B is coupled to the second housing 836. Other end of each of the first spring 840A and the second spring 840B is coupled to the spring arbor 842. Examples of the first spring 840A and the second spring 840B may include clock springs, torsion springs, or the like.

The spring arbor 842 may correspond to a rotatable shaft, which when rotated results in built-up of tension in the first spring 840A and the second spring 840B. In other words, when the spring arbor 842 is rotated in a first direction, the first spring 840A and the second spring 840B get compressed and store potential energy therein. Further, when the power providing rotation torque to the spring arbor 842 fails or is turned off, the potential energy stored in the first spring 840A and the second spring 840B causes the spring arbor 842 to rotate in a reverse direction, thus uncompressing the first spring 840A and the second spring 840B. In other words, the spring arbor 842 rotates in the reverse direction and returns to an initial position due to spring action of the first spring 840A and the second spring 840B.

In some embodiments, the spring return fail-safe assembly 801A may further include a control mechanism 844 to control or limit a maximum speed at which the spring arbor 842 can return to its initial position due to the spring action of the first spring 840A and the second spring 840B. In some embodiments, the control mechanism 844 may be configurable to select one of a plurality of maximum speed options as the return. However, it should be understood that control mechanism 844 is an optional component. As such, the control mechanism 844 may be omitted without departing from the scope of the present disclosure.

The spring return fail-safe assembly 801A, when removably coupled with the actuator 800, converts the actuator 800 to function as a spring return fail-safe actuator. Functional details of the actuator 800 when coupled with the spring return fail-safe assembly 801A are described in greater detail in conjunction with FIG. 11.

Referring particularly to FIG. 8C, the energy storage return fail-safe assembly 801B is shown. The energy storage return fail-safe assembly 801B includes a third housing 846 having a third engagement mechanism 848. The third engagement mechanism 848 may include one or more clips, latches, snap mechanism, screws, etc. which enable the energy storage return fail-safe assembly 801B to be removably coupled to the base portion 808 of the actuator 800, once the top cover portion 810 is removed from the base portion 808. The third engagement mechanism 848 may couple with the modular interface 818 of the actuator 800, allowing easy removal or attachment of the energy storage return fail-safe assembly 801B from/with the base portion 808. The third engagement mechanism 848 may hold the energy storage return fail-safe assembly 801B securely in place, when the energy storage return fail-safe assembly 801B is removably attached to the base portion 808. The energy storage return fail-safe assembly 801B may further include a grip mechanism (not shown) that allows a user/an operator to hold the energy storage return fail-safe assembly 801B while removing the energy storage return fail-safe assembly 801B from the base portion 808 or while placing the energy storage return fail-safe assembly 801B on the base portion 808. The third engagement mechanism 848 and the grip mechanism enable easy removal and placement of the energy storage return fail-safe assembly 801B from/on the actuator 800 without requiring any specialized tool.

The energy storage return fail-safe assembly 801B may further include at least one energy storage unit (ESU) 849, a controller 850, and one or more electric contacts 852 coupled to the controller 850. The ESU 849 may function as a return mechanism and may be housed within the third housing 846 along with the controller 850, and the electric contacts 852 may be exposed to facilitate an electric connection with another device, for example, the spring-loaded electrical connectors 826 of the actuator 800.

The energy storage return fail-safe assembly 801B operates based on the principle of energy storage and discharge within the ESU 849. For example, when the ESU 849 is coupled to a power source (directly or indirectly), the ESU 849 accumulates electrical charge, thus, storing electrical energy. However, when the power supply is cut off or when the voltage drops (intentionally or due to a failure), the ESU 849 discharges the electrical charge. In some embodiments, the ESU 849 may be charged until the voltage becomes greater than or equal to a voltage threshold value and if the ESU 849 is overcharged, the ESU 849 may be discharged. Examples of the ESU 849 may include a capacitor, a double layer capacitor, a supercapacitor, or any other suitable form of energy storage which has charging and discharging cycles.

The controller 850 may be coupled to the ESU 849 and the electric contacts 852. The controller 850 may be configured to receive a voltage signal (e.g., a power signal) and facilitate charging and discharging of the ESU 849 based on the voltage signal. For example, when the voltage signal is received, the controller 850 facilitates charging of the ESU 849, whereas when the voltage signal is turned off or when voltage drops due to a failure or a control action, the controller 850 facilitates discharging of the ESU 849. The controller 850 may further function as an energy converter which manages energy flux in two directions. For example, the controller 850 may be configured to step down the voltage signal to a lower voltage in order to charge the ESU 849. Further, the controller 850 may be configured to step up an output voltage signal of the ESU 849 when the ESU 849 is being discharged.

The energy storage return fail-safe assembly 801B, when removably coupled with the actuator 800, converts the actuator 800 to function as an energy storage return fail-safe actuator. Functional details of the actuator 800 when coupled with the energy storage return fail-safe assembly 801B are described in greater detail in conjunction with FIG. 10.

In some embodiments, the threshold voltage value to which the ESU 849 is charged may be a dynamically controlled value. For example, the controller 850 may be configured to determine the threshold voltage value based on a current position setpoint of the movable component 802. The controller 850 may determine a charging voltage required to drive the movable component 802 from the current position setpoint to a fail-safe position. Thus, when the position setpoint point of the movable component 802 changes, the threshold voltage value may be determined again. The controller 850 may trigger charging or discharging of the ESU 849 as per the threshold voltage value.

Both fail-safe and non-fail-safe actuators are tailored to specific applications. In fact, type of return mechanism (e.g., spring return or energy storage return) also dictates the suitability of fail-safe actuators for diverse applications. Thus, by providing the modular actuator system of FIGS. 8A-8C, an equipment manufacturer is not required to maintain different store keeping units (SKUs) or variants for the same torque rating actuator. The manufacturer may simply maintain the actuator 800 which can be modularly interfaced with different fail-safe assemblies 801A and 801B as per requirement. Thus, reducing the inventory, assembly, and storage costs. Further, such modularity enables switching from one actuator type to another without complete replacement as shown later in FIGS. 9-11.

In some embodiments, an option may be provided to customers to purchase the actuator 800 along with the fail-safe assemblies 801A and 801B. Alternatively, the fail-safe assemblies 801A and 801B can be purchased later as Add On attachments as per customer requirements. Thus, the actuator system of FIGS. 8A-8C can be tailored as per purchasing requirements of the customer.

Though FIGS. 8B and 8C illustrate two types of modular fail-safe assemblies, the scope of the disclosure is not limited to it. The actuator 800 via the modular interface 818 may be interfaceable with other modular fail-safe assemblies which match torque and speed rating of the actuator 800. In other words, the modular interface 818 may enable one of a plurality of fail-safe assemblies, which match torque and speed rating of the actuator 800, to be removably coupled to the opening of the base portion 808 upon removal of the top cover portion 810. Further, the scope of using the modular actuator system is not limited to HVAC&R or BMS applications. The modular actuator system may be used in any suitable application without deviating from the scope of the disclosure.

FIGS. 9-11 are block diagrams that demonstrate modular interfacing of the actuator 800 with the one or more fail-safe assemblies (e.g., the spring return fail-safe assembly 801A and the energy storage return fail-safe assembly 801B), according to some embodiments of the present disclosure. In a non-limiting example and for the sake of brevity, the energy storage return fail-safe assembly 801B is assumed to be a capacitor return fail-safe assembly 801B and the ESU 849 is assumed to be a capacitor 849 in the ongoing description.

Referring particularly to FIG. 9, the top cover portion 810 is shown to have been removed (or detached) from the base portion 808. Some applications may require a fail-safe functionality for controlling the movable component 802. For example, under normal operation, when an AHU shuts down, outside air intake and exhaust dampers (e.g., the movable component 802) are closed to prevent freezing in the dampers. However, if a control signal or power failure occurs when the dampers were open, a non-fail-safe actuator would be unable to bring the dampers to the close position and the dampers would remain stuck at the fully or partially open position, resulting in freezing. In such application scenarios, a fail-safe actuator may be preferred over a non-fail-safe actuator. Thus, the actuator 800 is required to be converted to a fail-safe actuator.

In order to attain fail-safe functionality in the actuator 800, the top cover portion 810 is removed and one of the spring return fail-safe assembly 801A and the capacitor return fail-safe assembly 801B that meets the application requirements is modularly interfaced with the actuator 800. For example, if a faster return stroke (e.g., 20 seconds) is required for an application, the spring return fail-safe assembly 801A may be interfaced with the actuator 800 instead of the capacitor return fail-safe assembly 801B. However, if a regular motor driven return stroke is suitable for an application, the capacitor return fail-safe assembly 801B may be interfaced with the actuator 800 instead of the spring return fail-safe assembly 801A. In other words, depending upon the application requirements, one of the spring return fail-safe assembly 801A and the capacitor return fail-safe assembly 801B is selected for attaining the fail-safe functionality in the actuator 800.

The spring-loaded electrical connectors 826 that were held in the depressed state due to the top cover portion 810, extend out of the base portion 808 in response to the removal of the top cover portion 810 from the base portion 808. FIG. 9 shows the spring-loaded electrical connectors 826 in the extended state.

Referring particularly to FIG. 10, the capacitor return fail-safe assembly 801B is shown to have been coupled to the actuator 800 upon removal of the top cover portion 810 from the base portion 808.

When the capacitor return fail-safe assembly 801B is placed on the base portion 808, the third engagement mechanism 848 engages with the modular interface 818 and the seal member 814 ensures a tight and reliable seal against the third housing 846. Thus, preventing any external elements (for example, water) from entering the first housing 806. The actuator 800 coupled with the capacitor return fail-safe assembly 801B functions as a capacitor return fail-safe actuator.

The controller 850 may couple with the processing circuitry 824 for receiving a power signal (e.g., a voltage signal) for charging the capacitor 849. In other words, the processing circuitry 824 provides the voltage signal to the controller 850 to enable charging of the capacitor 849. The extended spring-loaded electrical connectors 826 make conductive contact 900 with the electric contacts 852 of the capacitor return fail-safe assembly 801B. Thereby, electrically connecting the controller 850 to the motor 820, and indirectly connecting the capacitor 849 to the motor 820. The motor 820 may serve as a discharge circuitry for the capacitor 849.

In operation, the processing circuitry 824 may receive a control signal for controlling the motor 820. The processing circuitry 824 may further receive the position signals from the position sensors coupled to the motor 820 and/or the drive device 822. The processing circuitry 824 may then determine a position of the motor 820 and/or the drive device 822 and operate the motor 820 in accordance with the control signal. For example, the processing circuitry 824 may increase or decrease the rotation speed of the motor 820 to achieve the position setpoint. Rotation of the motor 820 may cause the drive device 822 (e., the gear train 828 and the hub 830) to drive the movable component 802 between open and closed positions, which in turn controls fluid flow or airflow through the conduit/duct 804. When the capacitor return fail-safe assembly 801B is coupled with the actuator 800, both forward and return strokes of the actuator 800 are controlled by the motor 820. Further, a speed of the forward and return strokes may be same. The processing circuitry 824 may further provide the voltage signal to the controller 850 to charge the capacitor 849.

During normal operation of the actuator 800, e.g., when no emergency event is experienced, the controller 850 may receive the voltage signal from the processing circuitry 824. The controller 850 may then provide a step down voltage signal as input to the capacitor 849 to charge the capacitor 849. In some embodiments, the controller 850 may measure a voltage across the capacitor 849, and when the voltage across the capacitor 849 becomes equal to or greater than the threshold voltage value, the controller 850 terminate the charging operation. The threshold voltage value may correspond to a value sufficient to implement the fail-safe operation during an emergency event.

In a scenario where the actuator 800 experiences an emergency event (for example, power failure, voltage drop, control signal failure, or any other fault), the capacitor return fail-safe assembly 801B implements a fail-safe operation in the actuator 800 to drive the movable component 802 to a fail-safe position. The fail-safe position may be a predetermined position designed to ensure safety and prevent any damage of the movable component 802 and/or HVAC&R system. Examples of the fail-safe position may include a fully opened position, a closed position, any specific partially opened position. For example, when there is a power failure or voltage drop, the controller 850 may not receive the voltage signal from the processing circuitry 824. In such a scenario, the controller 850 may be configured to trigger the fail-safe operation in the actuator 800.

During the fail-safe operation, the controller 850 may facilitate discharging of the capacitor 849 to drive the motor 820. For example, when the capacitor 849 discharges, the controller 850 may receive an output voltage signal from the capacitor 849. The controller 850 may step up the output voltage signal to a voltage level sufficient to drive the motor 820. The controller 850 may then provide the stepped-up output voltage signal to the motor 820 via the conductive contact 900. Thus, the capacitor 849 discharges via the motor 820 to power the motor 820, and in turn drive the movable component 802 to the fail-safe position. The electrical connection between the capacitor 849 and the motor 820 is such that when the capacitor 849 discharges, the motor 820 is driven to attain a home position corresponding to the fail-safe position. As and when the emergency event is resolved, the actuator 800 and the capacitor return fail-safe assembly 801B exhibits normal operation.

In some embodiments, the capacitor 849 may be discharged completely during the fail-safe operation. However, in some embodiments, the charge stored in the capacitor 849 may be more than the charge required to drive the movable component 802 from a current position to the fail-safe position. In such a scenario, the controller 850 may be configured to terminate the discharging operation in response to the movable component 802 attaining the fail-safe position, for example, before complete discharge of the capacitor 849. The capacitor return fail-safe assembly 801B may include additional components such as diodes, switches, sensors, etc. that enable the controller 850 to manage the charging and discharging cycles of the capacitor 849.

Referring particularly to FIG. 11, the spring return fail-safe assembly 801A is shown to have been removably coupled to the actuator 800 upon removal of the top cover portion 810 from the base portion 808. When the spring return fail-safe assembly 801A is placed on the base portion 808, the second engagement mechanism 838 engages with the modular interface 818 and the seal member 814 ensures a tight and reliable seal against the second housing 836. Thus, preventing any external elements (for example, water) from entering the first housing 806. The actuator 800 coupled with the spring return fail-safe assembly 801A functions as a spring return fail-safe actuator. The spring arbor 842 may form a mechanical linkage with the drive device 822 (e.g., the gear train 828) and/or the motor 820. The extended spring-loaded electrical connectors 826 may regain the depressed state without making conductive contact with the spring return fail-safe assembly 801A.

In operation, the processing circuitry 824 may receive a control signal for controlling the motor 820. The processing circuitry 824 may further receive the position signals from the position sensors coupled to the motor 820 and/or the drive device 822. The processing circuitry 824 may then determine a position of the motor 820 and/or the drive device 822 and operate the motor 820 in accordance with the control signal. For example, the processing circuitry 824 may increase or decrease the rotation speed of the motor 820 to achieve the position setpoint. Rotation of the motor 820 may cause the drive device 822 (e.g., the gear train 828 and the hub 830) to drive the movable component 802 between open and closed positions, which in turn controls fluid flow or airflow through the conduit/duct 804.

Since the spring arbor 842 gets coupled with the drive device 822, the spring arbor 842 also rotates in a first direction (e.g., clockwise or anti-clockwise) in response to the rotation of the drive device 822. As the drive device 822 (or the motor 820) is required to drive the spring arbor 842 along with the movable component 802, the processing circuitry 824 is required to provide higher torque and power to the motor 820 in comparison to when the capacitor return fail-safe assembly 801B or the top cover portion 810 are coupled with the actuator 800. The differences of torque requirement, power requirement, and conductive contact formation between the spring return fail-safe assembly 801A and the capacitor return fail-safe assembly 801B enables the processing circuitry 824 to determine which fail-safe assembly 801A and 801B is coupled to the actuator 800.

Due to the rotation of the spring arbor 842 by the drive device 822, the first spring 840A and the second spring 840B get compressed and store potential energy therein. When the spring return fail-safe assembly 801A is coupled with the actuator 800, the forward stroke of the actuator 800 is controlled by the motor 820 and the return stroke may be controlled by spring action (e.g., release of potential energy) of the spring return fail-safe assembly 801A. Further, a speed of the return stroke may be higher than a speed of the forward stroke. For example, forward stroke time may be 90 seconds, 150 seconds, etc. whereas the return stroke time may be 20 seconds, 30 seconds, etc.

In a scenario where the actuator 800 experiences an emergency event (for example, power failure, control signal failure, or any other fault), the spring return fail-safe assembly 801A implements a fail-safe operation in the actuator 800 to drive the movable component 802 to a fail-safe position. Examples of the fail-safe position may include a fully opened position, a closed position, any specific partially opened position. During the fail-safe operation, the potential energy stored in the first spring 840A and the second spring 840B causes the spring arbor 842 to rotate in a reverse direction and return to an initial position, thus uncompressing the first spring 840A and the second spring 840B. Rotation of the spring arbor 842 in the reverse direction drives the drive device 822 to its initial position, thus driving the movable component 802 to the fail-safe position. As and when the emergency event is resolved, the actuator 800 exhibits normal operation.

Due to modular interfacing, the spring return fail-safe actuator shown in FIG. 11 can be easily converted to a capacitor return fail-safe actuator shown in FIG. 10 or a non-failsafe actuator shown in FIG. 8A by swapping the spring return fail-safe assembly 801A with the capacitor return fail-safe assembly 801B or the top cover portion 810, respectively. Thus, providing more flexibility and ease of installation to customers.

FIG. 12 is a flow chart of a method 1200 to describe operation of the modular actuator 800, in accordance with some embodiments of the present disclosure. Operations 1202-1214 describe modular operation of the actuator 800.

At operation 1202, the processing circuitry 824 may be configured to determine whether any fail-safe assembly 801A and 801B is coupled to the actuator 800. The processing circuitry 824 may determine whether any fail-safe assembly 801A and 801B is coupled to the actuator 800 based on conductive state of the spring-loaded electrical connectors 826 in the actuator 800 and/or power and torque requirements for operating the motor 820. For example, when the conductive contact 900 is made or when the power and/or torque requirements are greater than a threshold value, the processing circuitry 824 determines that one of the fail-safe assemblies 801A and 801B is coupled to the actuator 800. However, when neither the conductive contact 900 is made nor the power and/or torque requirements are greater than the threshold value, the processing circuitry 824 determines that no fail-safe assembly is coupled to the actuator 800. The processing circuitry 824 may be configured to determine the power and/or torque requirements based on the position signal received from the position sensors coupled to the motor 820 and/or the drive device 822 after initial actuation. If at 1202, the processing circuitry 824 determines that a fail-safe assembly is coupled to the actuator 800, process proceeds to 1204.

At operation 1204, the processing circuitry 824 may be configured to determine fail-safe assembly type. The processing circuitry 824 may determine which fail-safe assembly 801A and 801B is coupled to the actuator 800 based on (i) whether conductive contact 900 is made and/or (ii) power and torque requirements for operating the motor 820. For example, when the conductive contact 900 is made, the processing circuitry 824 may determine that the capacitor return fail-safe assembly 801B is removably coupled to the actuator 800. However, when the conductive contact 900 is not made and the power and/or torque requirements are greater than the threshold value, the processing circuitry 824 determines that the spring return fail-safe assembly 801A is removably coupled to the actuator 800. If at 1204, the processing circuitry 824 determines that the spring return fail-safe assembly 801A is coupled to the actuator 800, process proceeds to operation 1206.

At operation 1206, the processing circuitry 824 may configure the forward and return strokes for spring return configuration. Thus, the forward stroke of the actuator 800 is controlled by the motor 820 and the return stroke may be controlled by spring action of the spring return fail-safe assembly 801A.

At operation 1210, the processing circuitry 824 may be configured to determine if there is any change in the modular configuration of the actuator 800. For example, the processing circuitry 824 may determine a change in the conductive contact 900 state and/or power and torque requirements for operating the motor 820. If at 1210, the processing circuitry 824 determines a change in the modular configuration of the actuator 800, process proceeds to 1202. However, if at 1210, the processing circuitry 824 determines no change in the modular configuration of the actuator 800, process remains at 1210 until any change is detected.

However, if at operation 1204, the processing circuitry 824 determines that the capacitor return fail-safe assembly 801B is coupled to the actuator 800, process proceed to operation 1212. At operation 1212, the processing circuitry 824 may configure the forward and return strokes for capacitor return configuration. Thus, the forward and return strokes of the actuator 800 are controlled by the motor 820. The process proceeds to operation 1210.

If at operation 1202, the processing circuitry 824 determines that no fail-safe assembly 801A and 801B is coupled to the actuator 800, process proceeds to operation 1214. At 1214, the processing circuitry 824 operates the actuator 800 in non-fail-safe configuration.

Configuration of Exemplary Embodiments

The construction and arrangement of the systems and methods as shown in the various exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements can be reversed or otherwise varied and the nature or number of discrete elements or positions can be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps can be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes, and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

The present disclosure contemplates methods, systems and program products on any machine-readable media for accomplishing various operations. The embodiments of the present disclosure can be implemented using existing computer processors, or by a special purpose computer processor for an appropriate system, incorporated for this or another purpose, or by a hardwired system. Embodiments within the scope of the present disclosure include program products including machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can include RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions.

Although the figures show a specific order of method steps, the order of the steps may differ from what is depicted. Also, two or more steps can be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

Claims

1. A modular actuator, comprising: a motor;a drive device driven by the motor and coupled to a movable component for driving the movable component; anda housing configured to house the motor and the drive device therein, and support modular interfacing with a plurality of fail-safe assemblies.

2. The modular actuator of claim 1, wherein in absence of a fail-safe assembly, the movable component retains a last position in response to power failure or control signal failure.

3. The modular actuator of claim 1, wherein a fail-safe assembly coupled to the housing operates the motor to drive the movable component from a last position to a fail-safe position in response to power failure or control signal failure.

4. The modular actuator of claim 3, wherein the fail-safe position comprises one of an open position and a closed position of the movable component.

5. The modular actuator of claim 1, wherein the plurality of fail-safe assemblies comprise a spring return fail-safe assembly and a capacitor return fail-safe assembly.

6. The modular actuator of claim 1, wherein the housing comprises a base portion and a top cover portion, wherein the motor and the drive device are housed within the base portion, and the top cover portion is removably coupled to conceal an opening of the base portion.

7. The modular actuator of claim 6, wherein the base portion comprises a seal member for ingress protection.

8. The modular actuator of claim 6, wherein the base portion comprises a modular interface that enables a fail-safe assembly among the plurality of fail-safe assemblies to be removably coupled to the opening of the base portion upon removal of the top cover portion.

9. The modular actuator of claim 6, wherein the base portion further comprises one or more spring-loaded electrical connectors electrically coupled to the motor.

10. The modular actuator of claim 9, wherein the one or more spring-loaded electrical connectors are held in a depressed state when the top cover portion is coupled to the base portion, and the one or more spring-loaded electrical connectors extend out of the base portion in response to removal of the top cover portion from the base portion.

11. The modular actuator of claim 10, wherein the one or more spring-loaded electrical connectors are configured to make conductive contact with a capacitor return fail-safe assembly removably coupled to the base portion.

12. The modular actuator of claim 10, wherein the one or more spring-loaded electrical connectors regain the depressed state without making conductive contact when a spring return fail-safe assembly is removably coupled to the base portion.

13. The modular actuator of claim 12, wherein the spring return fail-safe assembly is configured to form a mechanical linkage with the drive device.

14. The modular actuator of claim 12, wherein a return stroke of the modular actuator is controlled based on a spring action of the spring return fail-safe assembly.

15. The modular actuator of claim 10, further comprising processing circuitry configured to determine a fail-safe assembly among the plurality of fail-safe assemblies coupled to the base portion.

16. The modular actuator of claim 15, wherein the processing circuitry determines the fail-safe assembly among the plurality of fail-safe assemblies coupled to the base portion based on whether the one or more spring-loaded electrical connectors have made a conductive contact with the fail-safe assembly.

17. A modular fail-safe assembly for actuators, comprising: a return mechanism; anda housing configured to house the return mechanism and support modular interfacing with a non-fail-safe actuator, wherein the return mechanism is configured to implement a fail-safe operation in the non-fail-safe actuator in response to power failure or control signal failure, wherein the return mechanism is configured to be removably coupled to the modular fail-safe assembly.

18. The modular fail-safe assembly of claim 17, wherein the return mechanism comprises a capacitor.

19. The modular fail-safe assembly of claim 17, wherein the return mechanism comprises a spring.

20. An actuator system for use in a heating, ventilating, or air conditioning (HVAC) system to drive a movable HVAC component, the actuator system comprising: one or more fail-safe assemblies provided as modular attachments; anda modular actuator configured to support modular interfacing with the one or more fail-safe assemblies, the one or more fail safe assemblies being removably coupled to the modular actuator, wherein in response to power failure or control signal failure, a fail-safe assembly, of the one or more fail-safe assemblies, is configured to implement a fail-safe operation that drives the movable HVAC component to a fail-safe position.