The present invention is directed generally to actuators used to control air temperature inside a passenger compartment of a vehicle.
The ECU 114 includes memory and a processor (e.g., a microcontroller). The memory stores embedded software that is executable by the processor. The software causes the ECU 114 to obtain the temperature setpoint value from the control signal and determine a rotational angle command based on the temperature setpoint value. The software causes the ECU 114 to encode the rotational angle command in a command signal and send the command signal to the rotary actuator 112 (e.g., via conductors 130 and 132). The rotational angle command directs the rotary actuator 112 to turn a shaft (not shown) to a desired position that opens or closes a heater water valve (not shown) or positions one or more air temperature blend doors (not shown). Then, the rotary actuator 112 turns the shaft (not shown) to the desired position based on the rotational angle command.
Like reference numerals have been used in the figures to identify like components.
In the circuit 200, the blower fan switch 204, the A/C switch 206, and the thermostat switch 207 are not part of the ATC system 202 and may be controlled manually. The A/C switch 206, the thermostat switch 207, and the compressor clutch 218 may be components of an air conditioning subsystem configured to provide cooled air to the passenger compartment 205.
The blower fan switch 204 controls the blower assembly 216. The blower assembly 216 is configured to move air through at least one duct 228. The duct(s) 228 has/have one or more outlets 226 in fluid communication with the passenger compartment 205. The air condition subsystem may supply the cooled air to one or more of the duct(s) 228. In such embodiments, the cooled air travels through the duct(s) 228 and enters the passenger compartment 205 through the outlet(s) 226.
The ATC system 202 includes a rotary actuator 212, an input 208, a heat-supplying device 220, a first (“cab air”) sensor 222, and a second (“outlet air”) sensor 224. In the embodiment illustrated, the first and second sensors 222 and 224 have each been implemented as a thermistor. However, this is not a requirement.
The heat-supplying device 220 is connected to the duct(s) 228 and supplies heat thereto. Heat supplied by the heat-supplying device 220 travels through the duct(s) 228, exits therefrom through the outlet(s) 226, and enters the passenger compartment 205. The heat may be supplied to the duct(s) 228 as heated air that the blower assembly 216 helps move through the duct(s) 228. The blower fan switch 204, which controls the blower assembly 216, may determine a speed at which the heated air travels through the duct(s) 228.
The actuator 212 has an outer housing 258, inputs “N,” “P,” “Q,” “R,” and “S,” an output “O,” a shaft 260, one of more rotation components 262, a processor 264, and memory 266. Referring to
Referring to
The input “N” (labeled “POWER” in
The input “P” (labeled “CONTROL SIGNAL” in
Referring to
The input “R” (labeled “CAB TEMP” in
The input “S” (labeled “DUCT TEMP” in
The output “O” (labeled “LIN” in
The actuator 212 is connected to the heat-supplying device 220 by the shaft 260. The actuator 212 converts electrical power received from the power source 232 into rotary action by the shaft 260. The rotation component(s) 262 is/are configured to rotate the shaft 260 in response to commands from the processor 264. Referring to
The shaft 260 controls the heat that is injected into the passenger compartment 205 by the heat-supplying device 220. For example, the heat-supplying device 220 may be implemented as a heater water valve. In such embodiments, the shaft 260 opens or closes the heater water valve to control thereby an amount of heated air entering the duct(s) 228. Alternatively, the heat-supplying device 220 may be implemented as a blend door that controls or blends an amount of heated air and an amount of cooled air (e.g., supplied by the air conditioning subsystem) before the blend enters the passenger compartment 205 through the outlet(s) 226 of the duct(s) 228.
The processor 264 (e.g., a microcontroller) is connected to the memory 266. The memory 266 stores embedded software instructions 270 that are executable by the processor 264. The actuator 212 is implemented by one or more electronic components that is/are small enough to fit inside commercially available space. The instructions 270 may be configured to be stored on the memory 266, which is small enough to fit inside the commercially available space.
Unlike the prior art rotary actuator 112 (see
For example, the instructions 270 may cause the processor 264 to implement first and second temperature control loops. The first and second temperature control loops run simultaneously and may each be implemented as a proportional-integral-derivative (“PID”) control loop. The first temperature control loop receives, as inputs, the desired temperature setpoint value and the first measured temperature value and outputs a first temperature difference between the desired temperature setpoint value and the first measured temperature value. The instructions 270 may cause the processor 264 to determine a desired discharge temperature setpoint value based at least in part on the first temperature difference. The second temperature control loop receives, as inputs, the desired discharge temperature setpoint value and the second measured temperature value (from the second sensor 224) and outputs a second temperature difference between the desired discharge temperature setpoint value and the second measured temperature value.
The first temperature control loop has a relatively long time constant between receiving a new temperature setpoint value (encoded in the control signal) and the first measured temperature value corresponding to (e.g., being equal to a temperature encoded in) that new temperature setpoint value. The second temperature control loop has a relatively short time constant between receiving the desired discharge temperature setpoint value (from the first temperature control loop) and the second measured temperature value corresponding to (e.g., being equal to a temperature encoded in) the desired discharge temperature setpoint value. Thus, by using both the first and second temperature control loops to control the amount of heat entering the passenger compartment 205, the circuit 200 may respond quicker and/or more accurately to changes in the temperature setpoint value. Additionally, the circuit 200 may reduce fluctuations in the temperature of the discharged air.
Then, the instructions 270 may cause the processor 264 to calculate the rotational angle command value based at least in part on the first temperature difference and/or the second temperature difference. For example, when the first temperature difference is zero, the instructions 270 may cause the processor 264 to calculate a rotational angle command value that causes the heat-supplying device 220 to continue adding the same amount of heat to the passenger compartment 205. On the other hand, when the first temperature difference is other than zero, the instructions 270 may cause the processor 264 to calculate a new rotational angle command value that causes the heat-supplying device 220 to contribute more or less heat to the passenger compartment 205 based at least in part on the magnitude of the first and/or second temperature differences. The amount of heat contributed may be determined based on a predefined heating curve, a lookup table, and the like. For example, the first temperature difference may be used to lookup a corresponding desired discharge temperature setpoint value on the predefined heating curve, in the lookup table, and the like. Then, the second temperature difference may be calculated and used to determine the new rotational angle command value (e.g., using a lookup table, and the like).
Next, the instructions 270 cause the processor 264 to provide the rotational angle command value to the rotation component(s) 262. The rotation component(s) 262 rotate the shaft 260 in accordance with the rotational angle command value. The rotation of the shaft 260 increases or decreases heat contributed by the heat-supplying device 220 to change thereby the air temperature inside the passenger compartment 205. Thus, the processor 264 changes the rotary position of the shaft 260 to adjust the air temperature inside the passenger compartment 205 (e.g., to match a temperature indicated by the temperature setpoint value).
Optionally, the instructions 270 may cause the processor 264 to output diagnostic information onto the serial data bus 250 via the output “O.” By way of a non-limiting example, the serial data bus 250 may be connected to a recipient device (not shown) configured to receive the diagnostic information from the actuator 212.
The actuator 212 may be used instead of or in place of the rotary actuator 112 (see
The foregoing described embodiments depict different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected,” or “operably coupled,” to each other to achieve the desired functionality.
While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations).
Conjunctive language, such as phrases of the form “at least one of A, B, and C,” or “at least one of A, B and C,” (i.e., the same phrase with or without the Oxford comma) unless specifically stated otherwise or otherwise clearly contradicted by context, is otherwise understood with the context as used in general to present that an item, term, etc., may be either A or B or C, any nonempty subset of the set of A and B and C, or any set not contradicted by context or otherwise excluded that contains at least one A, at least one B, or at least one C. For instance, in the illustrative example of a set having three members, the conjunctive phrases “at least one of A, B, and C” and “at least one of A, B and C” refer to any of the following sets: {A}, {B}, {C}, {A, B}, {A, C}, {B, C}, {A, B, C}, and, if not contradicted explicitly or by context, any set having {A}, {B}, and/or {C} as a subset (e.g., sets with multiple “A”). Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of A, at least one of B, and at least one of C each to be present. Similarly, phrases such as “at least one of A, B, or C” and “at least one of A, B or C” refer to the same as “at least one of A, B, and C” and “at least one of A, B and C” refer to any of the following sets: {A}, {B}, {C}, {A, B}, {A, C}, {B, C}, {A, B, C}, unless differing meaning is explicitly stated or clear from context.
Accordingly, the invention is not limited except as by the appended claims.