Patent Application
20240188262
The present disclosure relates generally to building controllers. More particularly, the present disclosure relates to methods and devices for electromagnetic shielding within building controllers, such as Heating, Ventilation, and/or Air Conditioning (HVAC) controllers.
Building controllers are used to control one or more building control components of a building control system. Such building control systems can include Heating, Ventilation, and/or Air Conditioning (HVAC) systems, building security systems, building lighting control systems, and/or any other suitable building control system. The building controller may include electronic components that generate unwanted noise, (e.g., electrical currents and/or voltages) that may cause electromagnetic interference (EMI). Such EMI may cause performance degradation of other nearby components such as, for example, an antenna of the building controller. In some cases, EMI generated by devices external to a building controller (e.g. a cell phones, wireless transmitters, lightening, utility power grid transmission lines, household appliances such as microwave ovens, transformers, CRT monitors or televisions, etc.) can cause performance degradation of some internal components of the building controller under certain conditions. Thus, there is a desire for improved building controllers that are configured to contain, control and/or isolate unwanted noise (e.g., EMI).
The present disclosure relates generally to building controllers. More particularly, the present disclosure relates to building controllers, such as a Heating, Ventilation, and/or Air Conditioning (HVAC) controllers, with improved EMI shielding to help contain, control and/or isolate unwanted noise (e.g., EMI). In an example, a thermostat may include a display having a metal backing, a printed circuit board having a ground plane, and one or more electrical components mounted to the printed circuit board. The one or more electrical components may be mounted in a shielded region on the printed circuit board and between the ground plane of the printed circuit board and the metal backing of the display. One or more conductive side shield elements are positioned between the printed circuit board and the display and extend along at least part of at least two lateral sides of the shielded region of the printed circuit board. The one or more conductive side shield elements may be electrically connected to the ground plane of the printed circuit board and may provide a side shield that reduces at least some EMI generated by the one or more electrical components situated in the shielded region of the printed circuit board from escaping laterally out from between the ground plane of the printed circuit board and the metal backing of the display. The one or more conductive side shield elements may also help reduce at least some EMI generated external to the shielded region from entering laterally into the shielded region from between the ground plane of the printed circuit board and the metal backing of the display.
In another example, a thermostat may include a display having a metal backing, a printed circuit board having a ground plane, and a processor and/or memory mounted to the printed circuit board. The processor and/or memory may be mounted in a shielded region on the printed circuit board and between the ground plane of the printed circuit board and the metal backing of the display. The thermostat may include one or more conductive side shield elements positioned between the printed circuit board and the display and may extend along at least part of at least two lateral sides of the shielded region of the printed circuit board. The one or more conductive side shield elements may be electrically connected to the ground plane of the printed circuit board and may provide a side shield that reduces at least some Electro-Magnetic Interference (EMI) generated by the processor and/or memory situated in the shielded region of the printed circuit board from escaping laterally out from between the ground plane of the printed circuit board and the metal backing of the display.
An antenna may be operatively coupled to the printed circuit board and may be outside of and laterally spaced from the shielded region along one of the at least two lateral sides of the shielded region. The side shield may reduce at least some Electro-Magnetic Interference (EMI) that is generated by the processor and/or memory from reaching the antenna.
In another example, a thermostat may include a display having a metal backing, a printed circuit board having a ground plane, and a processor and/or memory mounted to the printed circuit board. The processor and/or memory may be mounted in a shielded region on the printed circuit board and between the ground plane of the printed circuit board and the metal backing of the display. The thermostat may include one or more conductive side shield elements positioned between the printed circuit board and the display and may extend along at least part of at least three lateral sides of the shielded region of the printed circuit board. The one or more conductive side shield elements may be electrically connected to the ground plane of the printed circuit board and may provide a side shield that reduces at least some Electro-Magnetic Interference (EMI) generated by the processor and/or memory situated in the shielded region of the printed circuit board from escaping laterally out from between the ground plane of the printed circuit board and the metal backing of the display. An antenna may be operatively coupled to the printed circuit board and laterally spaced from the shielded region along one of the at least three lateral sides of the shielded region.
The preceding summary is provided to facilitate an understanding of some of the innovative features unique to the present disclosure and is not intended to be a full description. A full appreciation of the disclosure can be gained by taking the entire specification, claims, figures, and abstract as a whole.
The disclosure may be more completely understood in consideration of the following description of various examples in connection with the accompanying drawings, in which:
While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular examples described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.
The following description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. The drawings, which are not necessarily to scale, depict examples that are not intended to limit the scope of the disclosure. Although examples are illustrated for the various elements, those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.
All numbers are herein assumed to be modified by the term “about”, unless the content clearly dictates otherwise. The recitation of numerical ranged by endpoints includes all numbers subsumed within that range (e.g., 1 to 5 includes, 1, 1.5, 2, 2.75, 3, 3.8, 4, and 5).
As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include the plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
It is noted that references in the specification to “an embodiment”, “some embodiments”, “other embodiments”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is contemplated that the feature, structure, or characteristic may be applied to other embodiments whether or not explicitly described unless clearly stated to the contrary.
The present disclosure relates generally to building controllers. More particularly, the present disclosure relates to methods and devices for electromagnetic shielding within building controllers, such as Heating, Ventilation, and/or Air Conditioning (HVAC) controllers. While HVAC controllers are used as an example below, it should be recognized that the concepts disclosed herein can be applied to building control systems more generally.
Building controllers, such as the illustrative HVAC controller 10 shown in
In some cases, the illustrative HVAC controller 10 may be a thermostat. The HVAC controller 10 may be configured to communicate with various components of the HVAC system via a wired link (not shown). In some cases, the HVAC controller 10 may be configured to communicate with the various components of the HVAC system via a wireless link (not shown). In some cases, the HVAC controller 10 may communicate over one or more wired or wireless networks that may accommodate remote access and/or control of the HVAC components via another device such as a smart phone, tablet, e-reader, laptop computer, personal computer, key fob, or the like. In some cases, the HVAC controller 10 may include a first communications port for communicating over a first network, and in some cases, a second communications port for communicating over a second network. In some cases, the first network may be a wireless local area network (WLAN), and the second network (when provided) may be a wide area network or a global network (WAN) including, for example, the Internet. In some cases, the remote devices may be configured to communicate wirelessly over the first network and/or the second network with the HVAC controller 10 via one or more wireless communication protocols including, but not limited to, cellular communication, ZigBee, REDLINK™, Bluetooth, WiFi, IrDA, dedicated short range communication (DSRC), EnOcean, and/or any other suitable common or proprietary wireless protocol, as desired.
In some instances, as shown in
In some cases, the display holder 13 may include an antenna recess 19 that is configured to accommodate at least a portion of an antenna 16. The antenna 16 may be operatively coupled to the PCB 20. In some cases, the antenna recess 19 may include an aperture 23 that permits the antenna 16 to pass through the display holder 13. In some cases, the antenna 16 may be considered as a flexible printed circuit (FPC) that fits at least partially into the antenna recess 19 and includes a connector cable 21 that extends from the antenna 16 and passes through a cable aperture 23 such that the connector cable 21 is able to be electrically connected to a connector on a printed circuit board (PCB) 20. The antenna 16 may be configured such that it is positioned within the antenna recess 19 which may be between the display 14 and the display holder 13. In some cases, the display 14 and/or metal backing layer 15 of the display 14 do not extend laterally to overlap with the antenna 16.
In some cases, the PCB 20 may include a grounding feature, such as a ground plane. In some cases, the ground plane may be a conductive layer of the PCB 20 connected to a grounding point of the PCB 20. The ground plane may serve as a return path for current from electrical components 22, such as a processor 24 or a memory 26, for example. In some cases, the ground plane extends laterally to cover most of the PCB 20. However, in some cases, the ground plane may not extend laterally to overlap with the antenna 16. In some cases, the ground plane may include one or more holes to accommodate feed throughs that allow signals to pass between layers of the PCB 20 without electrically contacting the ground plane.
In some cases, the PCB 20 may include one or more electrical components 22 mounted to the PCB 20 within and outside of a shielded region 35 on the PCB 20. The one or more electrical components 22 may include a memory (e.g., memory 26), a processor (e.g., processor 24), one or more sensors (e.g., a temperature sensor, a humidity sensor, an occupancy sensor, or the like), a microcontroller unit (MCU), and/or any other suitable components. The shielded region 35 may be positioned between the ground plane of the PCB 20 and the metal backing 15 of the display 14. The ground plane of the PCB 20 and the metal backing 15 of the display 14 provide a level of EMI shielding to the front and back of the shielded region 35.
As can be seen, the illustrative shielded region 35 include four lateral sides including a left side 36, a right side 37, a top side 38, and a bottom side 39. While the shielded region 35 is described as having four lateral sides, it may be considered that the shielded region 35 may include a different number of lateral sides, sometimes depending on the shape. One or more conductive side shield elements 30 are positioned between the PCB 20 and the display 14, and extend along at least part of at least two lateral sides of the shielded region 35. In some cases, the one or more conductive side shield elements 30 may be positioned along at least part of two opposing sides of the shielded region 35. In some cases, the one or more conductive side shield elements 30 may be positions along at least three sides of the shielded region 35. In other cases, the one or more conductive side shield elements 30 may be positioned along at least four sides of the shielded region 35. The one or more conductive side shield elements 30 may be electrically connected to the ground plane of the PCB 20 such that the conductive side shield elements 30 provide a side shield that reduces at least some EMI generated by the one or more electrical components 22 situated within the shielded region 35 of the PCB 20 from escaping laterally out from between the ground plane of the PCB 20 and the metal backing 15, and/or prevents at least some externally generated EMI from laterally entering the shielded region 35.
The one or more conductive side shield elements 30 may be configured to extend from the PCB 20 through the display recess 18 of the display holder 13 and may electrically connect the ground plane of the PCB 20 and the metal backing 15 of the display 14. In some cases, the one or more conductive side shield elements 30 may have a height of 1.5 millimeters (mm), 2.5 mm, 3.5 mm, or any other suitable height. In some cases, the one or more conductive side shield elements 30 may have a height sufficient to physically engage both the PCB 20 and the display 14. In some cases, the one or more conductive side shield elements 30 may be bonded to the PCB 20 (e.g. via an adhesive, solder, clipped or the like). In other cases, the one or more conductive side shield elements 30 may be bonded to the metal backing 15 of the display 14. In some cases, a first portion of the conductive side shield elements 30 may be bonded to the PCB 20 and a second portion may be bonded to the metal backing 15 of the display 14, and the first and second portions may engage one another during assembly of the thermostat 10.
The one or more conductive side shield elements 30 may include for example, but not limited to, one or more conductive springs 31 (as shown in
In some cases, one or more conductive contacts 32 (e.g. see
The one or more conductive side shield elements 30 may be configured to providing EMI shielding to the shielded region 35. The shielded region 35 may include one or more of the electrical components 22 (e.g., the processor 24, the memory 26) within. In some cases, the electrical components 22, such as the processor 24 and/or the memory 26, may operate at a frequency of greater than 50 megahertz (MHz) and/or may have an output rise time of less than 10 nanoseconds (ns). In some cases, the electrical components 22 may operate at a frequency of 2.4 gigahertz (GHz) or greater and/or may have an output rise time of less than 10 ns. In some cases, the electrical components 22 may operate at a frequency of 10 MHz or greater. These are just examples. The frequency that the electrical components 22 operate may create different noise in the form of an Electro-Magnetic Interference (EMI), which may interfere with the operation of other components of the HVAC controller 10, such as, for example, the antenna 16. When the electrical components 22 are provided within the shielded region 35, the shielded region 35 may reduce the noise (e.g., EMI) created by the electrical components 22 that are within the shielded region 35 from escaping laterally out from between the ground plane of the PCB 20 and the metal backing 15 of the display 14. In some cases, as shown in
As shown in
As shown in
The spacing of the conductive springs 31 may be dependent on the frequency of the unwanted EMI. For example, the spacing between the conductive springs 31 may be less for lower frequency unwanted EMI, and may be greater for higher frequency EMI. As such, by knowing the frequencies of the unwanted EMI (e.g. operating frequency of the processor, memory and/or other EMI emitting components on the PCB 20), the spacing between the conductive springs 31 may be identified and set. In some cases, the conductive springs 31 may be spaced less than 5 mm apart, between 5 mm and 10 mm apart, between 10 mm and 20 mm apart, between 20 mm and 30 mm apart, between 30 mm and 50 mm apart, greater than 50 mm apart, and or any other suitable spacing.
As shown in
The sub-region boundary 40 may include the one or more conductive side shield elements 30 positioned along at least part of the sub-region boundary 40. For example, as shown in
The sub-region boundary 40 may serve to reduce at least some of the EMI generated by the one or more electrical components 22 (e.g., the processor 24 and/or the memory 26) from escaping laterally out from the PCB 20 and engaging other components in another sub-region. For example, if the processor 24 operates at a frequency of 50 MHz, the one or more conductive side shield elements 30 of the sub-region boundary 40 help contain the EMI produced by the processor 24 within the second sub-region 42, thereby reducing interference with and/or degradation of the operation of the memory 26, the antenna 16, and/or any other electrical components 22 outside of the second sub-region 42.
Having thus described several illustrative embodiments of the present disclosure, those of skill in the art will readily appreciate that yet other embodiments may be made and used within the scope of the claims hereto attached. It will be understood, however, that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size, arrangement of parts, and exclusion and order of steps, without exceeding the scope of the disclosure. The disclosure's scope is, of course, defined in the language in which the appended claims are expressed.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/089750 | 4/26/2021 | WO |
