Valve assembly including an instinct valve

Abstract

An actuator assembly includes a resilient member configured to exert a bias force onto a plunger. The actuator assembly includes a shape memory alloy actuator configured to exert an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source. The actuator assembly includes contacts configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source to the switch. Oscillation of the contacts between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow fluid to flow through a fluid port as long as power is being provided from the energy source.

Description

VALVE ASSEMBLY INCLUDING AN INSTINCT VALVERELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 677,189, filed July 30, 2024 (Attorney Docket No. 031490-0013-US01), and to U.S. Provisional Application No. 63 / 677,180, filed July 30, 2024 (Attorney Docket No. 031490-0012-US01), the entire contents of each of which is hereby incorporated by reference.FIELD

[0002] The present disclosure relates to control of fluid flow (e.g., to and / or from a bladder configured to be selectively filled with fluid such as air) using one or more instinct valves. For example, the present disclosure relates to a pneumatic valve assembly for commercial and residential use, and more specifically for use within vehicular seating systems (aircraft, automobiles, etc.).BACKGROUND

[0003] Fluid control valves often use solenoids to open and close the valve. However, solenoids are often bulky, heavy, draw high current, generate noise, and generate heat.SUMMARY

[0004] A compact pump and pneumatic valve system is advantageous for use within vehicular seating systems to reduce the overall footprint of a system used to inflate and deflate air bladders within the seat. In general, the pump creates pressure differentials to either supply air to or exhaust air from the air bladder. One or more pneumatic valves control which air bladder(s) receives air for inflation or exhausts air for deflation. A pneumatic valve system provides a reliable and compact configuration for controlling air bladder arrangements in seating applications.

[0005] The present disclosure provides a configuration for a pump and a method of pumping air from a pump into a valve assembly. As described in greater detail below, the pump and valve assembly are coupled together to form a compact design. The resulting pump assembly may be advantageously used for pneumatic bladder systems where space is limited (e.g., in vehicle seats, massage chairs, etc.) and, therefore, a compact design is desirable.

[0006] For example, the present disclosure provides, in one aspect, a valve module for selectively allowing airflow from a pump to pass to one or more air bladders, the valve module including: a main housing; a pressure port configured to receive the airflow from the pump; a plurality of work ports are in fluid communication with the one or more air bladders; a first check valve and a second check valve are disposed within the housing and downstream of the pressure port, the first and second check valves selectively allow the airflow to pass through; a first actuator chamber in fluid communication with the first check valve and supporting a first shape memory alloy (SMA) actuator; a second actuator chamber in fluid communication with the second check valve and supporting a second shape member alloy (SMA) actuator; and an exhaust manifold that is disposed downstream both the first actuator chamber and the second actuator chamber, the exhaust manifold discharges the airflow to atmosphere upon energizing either the first SMA actuator or the second SMA actuator.

[0007] The present disclosure provides, in another aspect, a valve module for selectively allowing airflow from a pump to pass to one or more air bladders, the valve module including: a main housing; a pressure port configured to receive the airflow from the pump; a plurality of work ports are in fluid communication with the one or more air bladders; a first check valve and a second check valve are disposed within the housing and downstream of the pressure port, the first and second check valves inhibit the airflow from discharging out of the one or more air bladders; a first shape memory alloy (SMA) actuator downstream the first check valve; and a second shape member alloy (SMA) actuator downstream the second check valve, wherein the airflow is introduced into the one or more air bladders without actuating the first SMA actuator or the second SMA actuator.

[0008] Additionally, one or more actuators included in the valve assembly may include a shape memory alloy (SMA) actuator that may be more desirable than a solenoid actuator in many situations as described herein. Use of a SMA actuator involves precise energy control to the SMA actuator to prevent damage to the SMA actuator (e.g., over-actuation through overheating, over-contraction, over-extension, etc.) while still allowing the SMA actuator to function properly to open and close a valve. The present disclosure provides a configuration for a SMA actuator / actuator assembly and a method of operating a SMA actuator / actuator assembly of the valve assembly.

[0009] In one aspect, the disclosure provides an actuator assembly configured to cooperate with a housing to form a valve. The actuator assembly may include a support baseattachable to the housing. The actuator assembly may also include a plunger arranged on the support base and including a seal element arranged at an end of the plunger. The actuator assembly may also include a resilient member configured to exert a bias force onto the plunger. The bias force, when unopposed, may bias the plunger in a closed position that causes the seal element to seal a fluid port to prevent a flow of fluid through the fluid port. The actuator assembly may also include a shape memory alloy actuator configured to exert an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source. The actuation force may oppose the bias force from the resilient member and may move the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port. The actuator assembly may also include a switch including contacts configured to be actuated in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloy actuator. The switch may be configured to prevent power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated. The contacts of the switch may be configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source to the switch. Oscillation of the contacts of the switch between the actuated position and the unactuated position may cause the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

[0010] In another aspect, the disclosure provides a method of operating an actuator assembly. The method may include exerting, with a resilient member, a bias force onto a plunger. The bias force, when unopposed, may bias the plunger in a closed position that causes a seal element arranged at an end of the plunger to seal a fluid port to prevent a flow of fluid through the fluid port. The method may also include exerting, with a shape memory alloy actuator, an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source. The actuation force may oppose the bias force from the resilient member and may move the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port. The method may also include actuating contacts of a switch in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloyactuator. The method may also include preventing, with the switch, power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated. The method may also include oscillating the contacts of the switch between an actuated position and an unactuated position while power is being provided from the energy source to the switch. Oscillation of the contacts of the switch between the actuated position and the unactuated position may cause the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

[0011] In another aspect, the disclosure provides a fluid flow control system that may include a plurality of bladders configured to be selectively filled with a fluid. The fluid flow control system may also include a valve assembly in fluid communication with the plurality of bladders. The valve assembly may include a housing and a plurality of actuator assemblies that are configured to cooperate with the housing to form a plurality of valves. Each actuator assembly may include a support base attachable to the housing. Each actuator assembly also may include a plunger arranged on the support base and including a seal element arranged at an end of the plunger. Each actuator assembly also may include a resilient member configured to exert a bias force onto the plunger. The bias force, when unopposed, may bias the plunger in a closed position that causes the seal element to seal a fluid port to prevent a flow of fluid through the fluid port. Each actuator assembly also may include a shape memory alloy actuator configured to exert an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source. The actuation force may oppose the bias force from the resilient member and may move the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port. Each actuator assembly also may include a switch including contacts configured to be actuated in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloy actuator. The switch may be configured to prevent power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated. The contacts of the switch may be configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source to the switch. Oscillation of the contacts of the switch between the actuated position and the unactuated position may cause the shapememory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

[0012] Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a perspective view of an embodiment of a valve module / assembly, according to some example embodiments described herein.

[0014] FIG. 2 is an exploded view of the valve module / assembly of FIG. 1, illustrating check valves and shape memory alloy (SMA) actuator assemblies, according to some example embodiments described herein.

[0015] FIG. 3 is a top perspective view of an embodiment of the valve module / assembly of FIG. 1, illustrating atop cover removed to show the SMA actuator assemblies, according to some example embodiments described herein.

[0016] FIG. 4 is a bottom perspective, cross-sectional view of the valve module / assembly along line 4 — 4 of FIG. 3, illustrating a bottom cover removed to show the check valves and printed circuit board, according to some example embodiments described herein.

[0017] FIG. 5 is a perspective view of the SMA actuator assembly, illustrating a lever actuator interfaced therewith, according to some example embodiments described herein.

[0018] FIG. 6 is an exploded view of the SMA actuator assembly and the lever actuator, according to some example embodiments described herein.

[0019] FIG. 7 is a cross-section view of the valve module / assembly along line 7 — 7 of FIG. 1, illustrating the SMA actuator assembly in an extended (or closed) position and an airflow traveling towards an air bladder, according to some example embodiments described herein.

[0020] FIG. 8 is a cross-section view of the valve module / assembly along line 7 — 7 of FIG. 1, illustrating the SMA actuator assembly in a retracted (or open) position and anairflow discharging from an air bladder to an external atmosphere, according to some example embodiments described herein.

[0021] FIG. 9 is a cross-section view of the valve module / assembly along line 7 — 7 of FIG. 1, illustrating the SMA actuator assembly in a fully -retracted position, according to some example embodiments described herein.

[0022] FIG. 10 is a perspective view of another embodiment of a valve module / assembly, according to some example embodiments described herein.

[0023] FIG. 11 is an exploded view of the valve module / assembly of FIG. 10, illustrating check valves and shape memory alloy (SMA) actuator assemblies, according to some example embodiments described herein.

[0024] FIG. 12 is atop view of the valve module / assembly of FIG. 10, illustrating an airflow traveling toward a first pair of bladders, according to some example embodiments described herein.

[0025] FIG. 13 is a bottom view of the valve module / assembly of FIG. 10, illustrating the airflow traveling toward the first pair of bladders, according to some example embodiments described herein.

[0026] FIG. 14 is atop view of the valve module / assembly of FIG. 10, illustrating an airflow traveling toward a second pair of bladders, according to some example embodiments described herein.

[0027] FIG. 15 is a bottom view of the valve module / assembly of FIG. 10, illustrating the airflow traveling toward the second pair of bladders, according to some example embodiments described herein.

[0028] FIG. 16 is atop view of the valve module / assembly of FIG. 10, illustrating an airflow being discharged from the first pair of bladders to an external atmosphere, according to some example embodiments described herein.

[0029] FIG. 17 is a bottom view of the valve module / assembly of FIG. 10, illustrating the airflow being discharged from the first pair of bladders to an external atmosphere, according to some example embodiments described herein.

[0030] FIG. 18 illustrates a zoomed-in view of an end portion of the SMA actuator assembly of FIG. 5 that is opposite a seal element and that includes terminal connectors, according to some example embodiments described herein.

[0031] FIG. 19 illustrates a zoomed-in view of the end portion of the SMA actuator of FIG. 18 with a support base removed to make contacts of a switch more visible, according to some example embodiments described herein.

[0032] FIG. 20 illustrates a simplified schematic diagram of a portion of the electrical components of the valve modules / assemblies of FIGS. 1-19, according to some example embodiments described herein.

[0033] FIG. 21 illustrates a flowchart of a manner in which power provided to a shape memory alloy (SMA) wire is controlled to oscillate, according to some example embodiments described herein.DETAILED DESCRIPTION

[0034] Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings.

[0035] In addition, it should be understood that embodiments may include hardware, software, and electronic components or modules that, for purposes of discussion, may be illustrated and described as if the majority of the components were implemented solely in hardware. However, one of ordinary skill in the art, and based on a reading of this detailed description, would recognize that, in at least one embodiment, the electronic-based aspects may be implemented in software (e.g., stored on non-transitory computer-readable medium)executable by one or more processing units, such as a microprocessor and / or application specific integrated circuits (“ASICs”). As such, it should be noted that a plurality of hardware and software-based devices, as well as a plurality of different structural components, may be utilized to implement the embodiments. For example, “servers,” “computing devices,” “controllers,” “processors,” etc., described in the specification can include one or more processing units, one or more computer-readable medium modules, one or more input / output interfaces, and various connections (e.g., a system bus) connecting the components.

[0036] Relative terminology, such as, for example, “about,” “approximately,” “substantially,” etc., used in connection with a quantity or condition would be understood by those of ordinary skill to be inclusive of the stated value and has the meaning dictated by the context (e.g., the term includes at least the degree of error associated with the measurement accuracy, tolerances [e.g., manufacturing, assembly, use, etc.] associated with the particular value, etc.). Such terminology should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression “from about 2 to about 4” also discloses the range “from 2 to 4”. The relative terminology (e.g., “about,” “approximately,” “substantially,” etc.) may refer to plus or minus a percentage (e.g., 1%, 5%, 10%, or more) of an indicated value.

[0037] It should be understood that although certain drawings illustrate hardware and software located within particular devices, these depictions are for illustrative purposes only. Functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. In some embodiments, the illustrated components may be combined or divided into separate software, firmware and / or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing may be distributed among multiple electronic processors. Regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among different computing devices connected by one or more networks or other suitable communication links. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. Forexample, a device or structure that is “configured” in a certain way is configured in at least that way but may also be configured in ways that are not explicitly listed.

[0038] As explained previously herein, fluid control valves (e.g., exhaust passages, fill passages, and / or the like) often use solenoids to open and close the valve. However, solenoids are often bulky, heavy, draw high current, generate noise, and generate heat. Accordingly, an alternative actuator (such as a shape memory alloy (SMA) actuator) for fluid control valves is more desirable than a solenoid actuator in many situations. For example, for similar applications, a SMA actuator may be smaller in size (i.e., less bulky), lighter in weight, draw less current, generate less noise, generate less heat, and / or be less expensive than a solenoid actuator. However, use of a SMA actuator involves precise energy control to the SMA actuator to prevent damage to the SMA actuator (e.g., over-actuation through overheating, over-contraction, over-extension, etc.) while still allowing the SMA actuator to function properly to open and close a valve.

[0039] Accordingly, there is a technological problem with using SMA actuators for fluid control valves in that such use of SMA actuators involves precise energy control to allow the SMA actuator to properly function without being damaged. The devices, methods, and systems disclosed herein address this technological problem by providing an instinct valve that includes a closed loop control system that oscillates between (i) allowing power to be provided to the SMA actuator and (ii) preventing power from being provided to the SMA actuator when the valve is in an open position. Such oscillation prevents damage to the SMA actuator while allowing the SMA actuator to remain in at least a partially actuated position that allows the valve to remain open at desired times. As explained below, in some instances, the closed loop control system is an analog system that does not necessarily involve a microcontroller or other controller as part of the valve assembly itself, which allows the system associated with the valve to be simple, inexpensive, and easier to manufacture and install while still providing desired functionality.

[0040] FIGS. 1 and 2 illustrates a valve module 100 (i.e., a valve assembly 100) including a main housing 104 having an actuator region 108, an air supply region 112, and a connector region 116. The actuator region 108 and the air supply region 112 are formed as one monolithic component, while in other embodiments, the actuator region 108 and the air supply region 112 can be formed as separate components that are coupled together. The connector region 116 is disposed adjacent and coupled to the air supply region 112. Themain housing 104 further includes a top cover 118 and a bottom cover 122, which respectively span across the top and bottom sides of portions of the actuator region 108, the air supply region 112, and the connector region 116. The top cover 118 and the bottom cover 122 may be laser welded to portions of the actuator region 108 and the air supply region 112 to form an airtight seal.

[0041] The connector region 116 may be configured to house and / or be coupled to a connector 124 that is configured to be electrically and physically coupled to a mating connector to receive signals / control commands from a control system. For example, the connector 124 may be communicatively coupled to a control system (e.g., a microcontroller or other electronic processor) of an automobile that is configured to provide a control command to actuate one or more actuator assemblies 170 to allow fluid flow and provide a desired output by selectively filling one or more bladders with pressurized air or releasing pressurized air from one or more bladders. In some instances, the control system of the automobile may receive a user input (e.g., via a button on a seat to be adjusted) that indicates that a comfort setting of the seat should be adjusted. The control system may process this user input and provide one or more control commands to the valve assembly 100 via the connector 124. In some instances, the control command(s) provided to the valve assembly 100 is merely a voltage (e.g., Vcc) that is provided to select pins of the connector 124 to actuate a respective actuator assembly (ies) to open a respective fluid port(s) (e.g., an exhaust passage 178) as described herein. In other words, the control system may provide a certain voltage to certain pins of the connector 124 of the valve assembly 100 to actuate certain actuator assemblies 170 (and / or other actuators) and may cease or refrain from providing the certain voltage (e.g., provide zero Volts) to certain pins of the connector 124 of the valve assembly 100 to deactivate certain actuator assemblies 170 (and / or other actuators) or maintain certain actuator assemblies 170 (and / or other actuators) in an unactuated position to close a respective fluid port(s) (e.g., an exhaust passage 178) as described herein.

[0042] The main housing 104 of the valve module 100 defines an exhaust manifold 126, a plurality of work ports 130, and a pressure port 134. The pressure port 134 is located on the air supply region 112, while the discharge manifold 126 and each of the work ports 130 are located on the actuator region 108. As described in greater detail below, pressurized air from a pressurized air source (i.e., an external pump) enters the main housing 104 through the pressure port 134. The pressurized air is then selectively directed through one or more of thework ports 130 to introduce the air into and inflate an associated bladder (not shown) connected to the work port 130. Each inflated bladder may be subsequently deflated by venting air from the bladder back into the main housing 104 through the associated work port 130, and then discharging the air from the main housing 104 into the surrounding atmosphere through the exhaust manifold 126.

[0043] FIGS. 2 and 3 illustrates the valve module 100 with the top cover 118 removed. The actuator region 108 includes a plurality of parallel dividing walls 138 extending upward from a base 140 and between a first end wall 142 and a second end wall 146 opposite the first end wall 142 (FIG. 3). The walls 138, 142, 146, the base 140, and part of the top cover 118 collectively define two parallel actuator chambers 150. The actuator chambers 150 are located on a top side of the base 140 (i.e., between the base 140 and the top cover 118). The work ports 130 extend through the first end wall 142 such that each work port 130 fluidly communicates with a respective one of the actuator chambers 150.

[0044] With continued reference to FIGS. 2 and 3, the main housing 104 includes a supply manifold 154 defined by the air supply region 112 to distribute pressurized air received from the pressure port 134 to the actuator chambers 150. The supply manifold 154 includes supply passages 158 that lead to check valves 162. In this embodiment, there are two supply passages 158 and two check valves 162, where each supply passage 158 is in fluid communication with a respective check valve 162. In other embodiments, there may be fewer or greater than two supply passages 158 and check valves 162. Downstream of the check valves 162 is a pair of transfer manifolds 166 located between base 140 and bottom cover 122 under actuator chambers 150 (FIG. 4). The transfer manifolds 166 are in fluid communication with the check valves 162 via transfer passages 168 formed in the base 140 on the bottom side of the base 140 (FIG. 4). The pair of transfer manifolds 166 is disposed between the supply manifold 154 and the actuator chambers 150 along an airflow path AF.

[0045] The valve module 100 further includes a pair of shape memory alloy (“SMA”) actuator assemblies 170 each disposed within a separate actuator chamber 150. That is, each actuator chamber 150 contains only one SMA actuator assembly 170. As further described below, each SMA actuator assembly 170 is operable to open or close a first fluid port (e.g., a fill passage 174) formed in the base 140 of the actuator region 108 to control the flow of pressurized air along airflow path AF from the transfer manifolds 166 into the actuatorchamber 150, as shown in FIGS. 2 and 4. The SMA actuator assemblies 170 are enclosed by the top cover 118 and the main housing 104 (e.g., within the actuator region 108).

[0046] With reference to FIG. 3, each SMA actuator assembly 170 is also operable to open or close a second fluid port (e.g., an exhaust passage 178) (see also FIG. 4) formed in the second end wall 146 of each actuator chamber 150 to selectively exhaust pressurized air along airflow path AF from the actuator chamber 150 to exhaust manifold 126. In turn, exhaust manifold 126 (FIG. 3) fluidly communicates with a plurality of exhaust holes 182 formed in the top cover 118 (FIGS. 1 and 2) to exhaust pressurized air from each air chamber 150 into the surrounding atmosphere.

[0047] With reference to FIG. 4, valve module 100 includes a printed circuit board (PCB) 186 supported within the main housing 104 below base 140 and the actuator chambers 150. Specifically, the PCB 186 is disposed between the base 140 of the actuator region 108 and the bottom cover 122. Each SMA actuator assembly 170 is electrically connected to the PCB 186 such that the PCB 186 supplies power to selectively energize each of the SMA actuator assemblies 170, as described in greater detail below. In some instances, the PCB 186 is electrically connected to the connector 124, to components of each actuator assembly 170, and / or to additional electrical components. In some instances, the PCB 186 electrically connects the connector 124 to components of each actuator assembly 170 to allow the control system of the automobile to selectively provide a voltage to an SMA actuator / wire 222 of each actuator assembly 170 as described herein.

[0048] Referring to FIGS. 5 and 6, each SMA actuator assembly 170 includes a plunger 190 and a support base 194 with a pair of support projections 198 that support the plunger 190 for sliding movement in a linear direction along a longitudinal axis 200 (FIG. 6) of the plunger 190. A seal element 202 is supported at a front-end portion 206 of the plunger 190. A resilient member 218 (e.g., a coil spring 218) surrounds the plunger 190 and extends between the front-end portion 206 of the plunger 190 and the opposite support projection 198 on the support base 194. The spring 218 abuts the support projection 198 on the support base 194 but is not fixed to the projection 198 or to any other part of the support base 194. The spring 218 biases the plunger 190 forward toward a closed or extended position, in which the seal element 202 blocks and closes the associated exhaust passage 178. The SMA actuator assembly 170 also includes an SMA actuator / wire 222 and a pair of wire terminal connectors 226, 228, as shown in FIG. 6. The SMA wire 222 is arranged in a U-shape with a first freeend 230 mechanically and electrically connected to a first terminal connector 226, a second free end 234 mechanically and electrically connected to a second terminal connector 228, and a bent middle section 238 wrapped about the front-end portion 206 of the plunger 190. In other words, an end of the plunger 190 undemeath / inside of the seal element 202 includes a portion (e.g., a rounded portion) with a groove (e.g., a rounded groove) configured to house the SMA wire 222. The SMA wire 222 may run / extend from one of the first terminal connector 226 at a first end of the support base 194 to and through the groove on the plunger 190 at an opposite end of the support base 194 and then back to the second terminal connector 228 at the first end of the support base 194. As shown in in FIG. 5, the SMA wire / actuator 222 extends parallel to a direction in which the plunger 190 extends.

[0049] To actuate the SMA actuator assemblies 170, the PCB 186 provides an electric current (e.g., from a pin of the connector 124) to flow through the SMA wire 222 via the first and second wire terminals 226, 228. The current heats the SMA wire 222, causing the SMA wire 222 to contract in length. As the SMA wire 222 contracts, the plunger 190 is linearly moved away from the corresponding exhaust passage 178, at which point the SMA actuator assembly 170 is in an open or retracted position. To subsequently close the exhaust passage 178, the current provided to the SMA wire 222 is ceased or reduced. The SMA wire 222 cools and stretches back to its de-energized extended length in response to the spring 218 exerting a biasing force on the plunger 190 and the SMA wire 222. Eventually, the spring 218 biases the plunger 190 back toward the exhaust passage 178 until the seal element 202 contacts the second end wall 146 of the actuator region 108 to block and close the exhaust passage 178, at which point the SMA actuator assembly 170 is in the extended position. In other words, the SMA wire 222 is configured to exert an actuation force onto the plunger 190 when the SMA wire 222 is powered by an energy source (e.g., voltage received from a control system of an automobile via the connector 124). The actuation force opposes the bias force from the resilient member 218 and moves the plunger 190 to an open position that causes the seal element 202 to be moved away from the exhaust passage 178 to allow the flow of the fluid through the exhaust passage 178.

[0050] The resilient member 218, the SMA wire 222, and the voltage applied to the SMA wire 222 are selected such that the actuation force is greater than the bias force. A greater actuation force than bias force causes the plunger 190 to move toward the end of the support base 194 that includes the terminal connectors 226, 228 such that the plunger 190 moves tothe open position that results in the seal element 202 being moved away from the exhaust passage 178 to allow the flow of the fluid through the exhaust passage 178. Upon stopping activation of the SMA wire 222 (e.g., ceasing providing voltage / current / power to the SMA wire 222), the plunger 190 moves back to the closed position due to the bias force provided by the resilient member 218 as the unpowered SMA wire 222 moves (e.g., expands) back to its unpowered shape. In other words, the bias force from the resilient member 218, when unopposed, biases the plunger 190 in a closed position that causes the seal element 202 to seal a fluid port (e.g., exhaust passage 178) to prevent a flow of fluid through the fluid port. In some embodiments, each of the SMA actuator assemblies 170 are operated separately of each other, while in other embodiments, the PCB 186 may instead control both SMA actuator assemblies 170 simultaneously.

[0051] In some instances, the SMA actuator 222 of the SMA actuator assembly 170 includes a SMA wire 222 as described above and as shown in FIGS. 5 and 6. In some instances, the SMA actuator 222 may be implemented by a wire-shaped SMA material or by a belt-shaped SMA material. While the SMA actuator 222 is referred to as a SMA wire 222 herein, other configurations of the SMA actuator 222 are conceivable. As indicated by the example described above, the SMA wire 222 provides a length change depending on its temperature. For example, the SMA wire 222 can be configured to reversibly change its shape due to thermal activation between an extended state and a contracted state. The extended and contracted states may correspond with the closed and opened positions of the plunger 190, respectively. However, in some instances, the extended and contracted states may be opposite and may correspond with the opened and closed positions of the plunger 190, respectively. The SMA wire 222 may provide such a shape change due to phase transformation between two or more solid-state phases. Typically, the transformation is between a low-temperature phase / martensitic phase to a high-temperature phase / austenitic phase. Typically, the phase transformation is reversible and independent of time.

[0052] In some instances, it is possible to activate the SMA wire 222 by feeding an electric current to the SMA material, i.e., by using the SMA wire 222 as an electric conductor. Due to the current flow, the SMA material is heated. The change in temperature causes the length change. In other examples, external heating elements arranged adjacent to the SMA wire 222 could be employed, e.g., separate current-carrying wires, etc. In the various examples described herein, different materials may be used for the SMA wire 222.Examples include a Nickel-Titanium (NiTi) alloy — e.g., binary NiTi alloys. For example, ternary or quaternary elements may be added to such a NiTi-based SMA wire 222, for example including carbon, oxide, copper, chromium, etc. Other examples for SMA wires 222 include copper-based alloys such as CuZnAl or CuAlNi.

[0053] With continued reference to FIG. 5 and 6, disposed within each actuator chamber 150 is a lever actuator 262. The lever actuator 262 includes a first or spring end 266, a second or cantilevered end 270, a fulcrum 274 about which the lever actuator 262 pivots, and a shoulder 278 that extends outward to interface with the plunger 190. The spring end 266 is constantly biased away from the support base 194 of each SMA actuator assembly 170 (or base 140 of the main housing 104) via a spring 282. The cantilevered end 270 includes a seal element 286 (that is similar to the seal element 202). The seal element 286 is configured to interface with a raised edge 140’ (FIG. 7-9) of the base 140 around the fill passage 174 of each actuator chamber 150 to effectively block the fill passages 174. In the illustrated embodiment, the lever actuator 262 is pivotably coupled to the support base 194 of each SMA actuator assembly 170 via the fulcrum 274, while in other embodiments, the lever actuator 262 may be alternatively coupled to the main housing 104 (e.g., the base 140, the dividing wall 138, etc.).

[0054] As previously mentioned, the shoulder 278 of the lever actuator 262 interfaces with the plunger 190. Specifically, the plunger 190 includes a finger 290 that extends in a direction perpendicular to the longitudinal axis 200 of the plunger 190. The finger 290 extends into the pivotal path of the lever actuator 262 and rests against the shoulder 278. The spring 282 of the lever actuator 262 biases the lever actuator 262 towards the finger 290, such that the lever actuator 262 moves in response to movement of the finger 290, and therefore, the plunger 190.

[0055] That is, when plunger 190 is extended to close exhaust passage 178 as illustrated in FIG. 7, finger 290 presses against shoulder 278 of lever actuator 262 to pivot the lever actuator 262 against the biasing force of spring 282 and open fill passage 174. This is a default position of the actuator assembly 170 in which the SMA wire 222 is de-energized without the application of an electric current. Pressurized air can then flow through fill passage 174 from transfer manifold 166, through actuator chamber 150, and out work port 130 to inflate an associated bladder in fluid communication with port 130.

[0056] When plunger 190 is retracted by activated SMA wire 222 to open exhaust passage 178, spring 218 biases the plunger 190 finger 290 moves away from and releases shoulder 278 of lever actuator 262, which allows the biasing force of spring 282 to pivot the lever actuator back to close the fill passage 174. With the exhaust passage 178 open and the fill passage 174 closed, the pressurized air that inflated the bladder is exhausted through work port 130 into the actuator chamber 150, out through exhaust passage 178 into exhaust manifold 126, and through exhaust holes 182 in the surrounding environment. The plunger 190 thus effectively controls movement of the lever actuator 262. For clarity, the lever actuator 262 is not powered by an SMA wire. Rather, the lever actuator 262 is akin to a follower mechanism (and may be referred to as such hereinafter) controlled by the movement of plunger 190.

[0057] In sum, the lever actuator 262 is moveable between an open position when the SMA actuator assembly 170 is in the extended position and a closed position when the SMA actuator assembly 170 is in the retracted position. Therefore, the SMA actuator assembly 170 and the lever actuator 262 may always be in opposite positions, such that when the fill passage 174 is open the exhaust passage 178 is closed, and vice versa.

[0058] As explained previously herein, use of the SMA wire 222 as part of the actuator assembly 170 involves precise energy / power control to the SMA wire 222 to prevent damage to the SMA wire 222 (e.g., over-actuation through overheating, over-contraction, over- extension, etc.) while still allowing the SMA wire 222 to function properly to open and close a valve / passage (e.g., allow fluid to flow through the exhaust passage 178 and prevent fluid from flowing through the exhaust passage 178). To provide such energy control, a switch 242 (e.g., a limit switch) including a first contact 254 and the second contact 250 may be utilized (see FIGS. 5-6 and 18-19).

[0059] In some instances, each SMA actuator assembly 170 includes the switch 242 (FIGS. 5-6 and 18-19) having a terminal 250 (i.e., the second contact 250) that is electrically coupled to the PCB 186 and extending through the support base 194. As shown in FIG. 6, an L-shaped conductive spring arm 254 (i.e., the first contact 254) is configured to interface with the second contact 250. The spring arm 254 extends into a travel path of the plunger 190, such that a rearward end 258 of the plunger 190 contacts and deflects the spring arm 254 toward the second contact 250 as the plunger 190 moves toward a fully retracted position (FIG. 9). When the spring arm 254 reaches and contacts the second contact 250, the switch242 is closed and a conductive pathway is established between the second contact 250 through the conductive spring arm 254. Closure of the switch 242 creates a control signal or otherwise causes the control system to reduce or stop / cease current flow through the SMA wire 222 as explained herein. The reduction or ceasing of current flow through the SMA wire 222 stops the contraction of the SMA wire 222 and thereby stops further movement of the plunger 190 in a direction away from the exhaust passage 178.

[0060] FIGS. 18-19 illustrate zoomed-in views of an end portion of the actuator assembly 170 that is opposite the seal element 202 and that includes the terminal connectors 226, 228. In FIG. 19, the support base 194 is removed to make the contacts 254 and 250 more visible. The end portion of the actuator assembly 170 shown in FIGS. 18-19 includes the first contact 254 and the second contact 250 arranged co-linearly with respect to each other and colinearly with the plunger 190. In some instances, the second contact 250 is a stationary contact. In some instances, the first contact 254 (e.g., a leaf spring contact) is a moveable contact that is biased at a distance away from the second contact 250 as shown in FIGS. 18- 19. In other words, the switch 242 includes the first contact 254 and the second contact 250 that are configured to be located a distance from each other so as to cause an open circuit between the first contact 254 and the second contact 250 in an unactuated position of the contacts 250 and 254 to prevent current flow between the first contact 254 and the second contact 250 when the contacts 254 and 250 are not being acted upon by other forces. In some instances, the first contact 254 is configured to be moved, by the plunger 190 due to the actuation force exerted by the SMA wire 222, to contact the second contact 250 so as to cause a closed circuit between the first contact 254 and the second contact 250 in the actuated position of the contacts 254 and 250 to allow current flow between the first contact 254 and the second contact 250.

[0061] In operation, to fill one or more bladders, an external pump (not shown) that is fluidly connected to pressure port 134 is turned on to create the airflow path AF through the valve module 100 via the pressure port 134 and supply manifold 154 (FIG. 3). After the pressurized air passes beyond the check valves 162 along the airflow path AF and through the transfer manifolds 166, the pressurized air enters the actuator chambers 150 via the fill passage 174 (FIG. 4). The fill passage 174 is, by default, open since the SMA wire 222 is deenergized and the SMA actuator assemblies 170 are in the extended (or closed) positions, such that the finger 290 biases the lever actuator 262 toward the open position (FIG. 7). Withthe fill passage 174 uncovered, pressurized air flows through the fill passage 174, through the actuator chamber 150, and out the work ports 130 to inflate the associated bladder, as shown in FIG. 7.

[0062] Once the bladder is filled, the lever actuator 262 remains in the open position and the pressurized air is inhibited from escaping the air bladders via the check valves 162. That is, the pressurized air remains in the air bladders because the airflow path AF from the bladders to the work ports 130, through the actuator chambers 150 cannot exhaust through the closed exhaust passages 178 to the exhaust manifold 126 and the pressurized air is inhibited from passing from the transfer passages 168 by the check valves 162.

[0063] FIGS. 8 and 9 illustrate actuation of the SMA actuator assembly 170 to selectively deflate the bladder via the work port 130. The PCB 186 directs an electric current to flow through the SMA wire 222 which heats the wire and causes the SMA wire 222 to contract in length. This, in turn, causes the plunger 190 to retract as well to the retracted (or open) position, as shown in FIG. 8. When the SMA actuator assembly 170 retracts, the seal of the plunger finger 290 releases the lever actuator 262 to close the fill passages 174 while the seal element 202 uncovers the exhaust passage 178. As a result, the pressurized air flows out of the bladder along the airflow path AF, through work port 130, through the actuator chamber 150, and out through the exhaust passage 178. Here, the pressurized air flows into the exhaust manifold 126 and through the plurality of holes 182 to the surrounding atmosphere. As shown in FIG. 9, the SMA actuator assembly 170 eventually reaches the fully retracted position, at which point the plunger 190 pushes the spring arm 254 into contact with the second contact 250, causing the switch 242 to close. As previously mentioned, closure of the switch 242 creates a control signal or otherwise causes the control system to reduce or stop / cease current flow through the SMA wire 222. The reduction or ceasing of current stops the contraction of the SMA wire 222 and thereby stops further movement of the plunger 190. Now, the SMA actuator assembly 170 is de-energized, and the seal element 202 begins to return to cover the exhaust passage 178. Specifically, the PCB 186 terminates the current flow through the SMA wire 222, where the SMA wire 222 cools and stretches back to its deenergized extended length via the spring 218 exerting a biasing force on the plunger 190. Eventually, the spring 218 biases the plunger 190 back toward the exhaust passage 178 until the seal element 202 contacts the main housing 104 to block and close the exhaust passage

[0064] FIG. 20 illustrates a simplified schematic diagram 2000 of a portion of the electrical components of the valve assembly 100. As shown in FIG. 20, the connector 124 may include a first pin that is electrically connected to the first contact 254 to receive a voltage from the control system / energy source 2005 (e.g., of an automobile). The second contact 250 may be connected to electrical ground as shown. In some instances, the connections may be opposite with the second contact 250 being electrically connected to the first pin of the connector 124 to receive a voltage from the control system / energy source 2005, and the first contact 254 being connected to electrical ground. In some instances, a switch 2010 that includes the first contact 254 and the second contact 250 also includes a switching element 2015. The switching element 2015 may be a transistor (e.g., a field effect transistor (FET), an insulated gate bipolar transistor (IGBT), or the like). The switching element 2015 may be electrically coupled to the first contact 254, the second contact 250, or both the first contact 254 and the second contact 250 to operate differently depending on whether the first contact 254 and the second contact 250 are in the unactuated position (i.e., not in contact with each other) or the actuated position (i.e., in contact with each other).

[0065] For example, the switching element 2015 may be wired in series between the SMA wire 222 and a second pin of the connector 124 that selectively provides power (i.e., energy, current, voltage, etc.) from the control system / energy source 2005 when a respective actuator assembly 170 should be actuated, for example, in response to user input as explained previously herein. In some instances, the switching element 2015 is configured to (a) allow current flow from the energy source 2005 to the SMA wire 222 when the first contact 254 and the second contact 250 are in the unactuated position (i.e., not in contact with each other), and (b) prevent current flow from the energy source 2005 to the SMA wire 222 when the first contact 254 and the second contact 250 are in the actuated position (i.e., in contact with each other).

[0066] In other words, when the energy source 2005 initially provides power to the SMA wire 222, the switching element 2015 is closed and allows current to flow to the SMA wire 222 since the contacts 254 and 250 are in the unactuated position due to the SMA wire 222 being at room temperature and in an extended state that does not oppose the bias force from the resilient member 218 on the plunger 190. Accordingly, the plunger 190 is biased away from the first contact 254 as shown in FIGS. 18-19 such that the contacts 254 and 250 are in the unactuated position (i.e., not in contact with each other). As power is continued to beprovided to the SMA wire 222, the SMA wire 222 contracts and causes the plunger 190 to move toward the first contact 254 to eventually move / push the first contact 254 into contact with the second contact 250 (i.e., the actuated position of the contacts 254 and 250). In response to the contacts 254 and 250 being in the actuated position, the switching element 2015 creates an open circuit between the connector 124 and the SMA wire 222 (i.e., disconnects power from being provided to the SMA wire 222) to prevent current flow from the energy source 2005 to the SMA wire 222.

[0067] Because the SMA wire 222 is no longer powered, its temperature decreases. The decreased temperature causes expansion of the SMA wire 222 and a lessening of the actuation force. Accordingly, the bias force of the resilient member 218 moves the plunger 190 back toward the exhaust passage 178, which allows the first contact 254 to be biased away from (i.e., out of contact with) the second contact 250 (i.e., the unactuated position of the contacts 254 and 250). In response to the contacts 254 and 250 being in the unactuated position, the switching element 2015 closes to create a complete / closed circuit between the connector 124 and the SMA wire 222 to re-allow current flow from the energy source 2005 to the SMA wire 222 assuming that the energy source 2005 is still applying power to the second pin of the connector 124 that connects to the switching element 2015.

[0068] As indicated by the above explanation, the switch 2010 includes contacts 254 and 250 that are configured to be actuated in response to the plunger 190 being moved a predetermined distance by the actuation force exerted by the SMA wire 222. Additionally, the switch 2010 is configured to disconnect power from being provided to the SMA wire 222 from the energy source 2005 when the contacts 254 and 250 are actuated. The contacts 254 and 250 of the switch 2010 are configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source 2005 to the switch 2010 of the respective actuator assembly 170 (i.e., while the respective actuator assembly 170 is activated such as by receiving power via a pin of the connector 124 that connects to the switch 2010 of the respective actuator assembly 170). The oscillation of the contacts 254 and 250 of the switch 2010 between the actuated position and the unactuated position causes the SMA wire 222 to expand and contract in a range of movement (a) that limits the movement of the SMA wire 222 when power is applied to the SMA wire 222 and (ii) that maintains the plunger 190 in the open position to allow the fluid to flow through the fluid port (e.g., exhaust passage 178) as long as power is being provided from the energy source 2005 to theswitching element 2015 of the actuator assembly 170. For example, the size and / or length of the SMA wire 222 and the predetermined distance that the plunger 190 must travel to place the contacts 254 and 250 in the actuated position may be designed such that as long as power from the energy source 2005 is being provided to the second pin of the connector 124 that is connected to the circuit path that includes the SMA wire 222 (e.g., to the switching element 2015), the plunger 190 may move back toward the fluid port (e.g., exhaust passage 178) when the SMA wire 222 is unpowered but the plunger 190 will not move far enough to seal the fluid port before the switching element 2015 re-closes the circuit to re-power the SMA wire 222.

[0069] Thus, using purely analog control as described above, over- actuation (e.g., overcontraction) of the SMA wire 222 may be prevented while maintaining the plunger 190 in the open position for a desired time in which power is provided from the energy source 2005 to the second pin of the connector 124 that is connected to the circuit path that includes the SMA wire 222 (e.g., to the switch 2010, which may include the switching element 2015). Using a purely analog method allows for an easily manufacturable and cost-efficient solution to the above-noted technological problem, for example, without using a microprocessor as part of the valve assembly 100 itself (e.g., the PCB 186 may not include a microprocessor for controlling power provided to the SMA wire 222). However, in some instances, one or more microprocessors may be used (e.g., when a microprocessor is already provided for other control actions and has available pins that can be leveraged for control of the valve assembly 100).

[0070] The schematic diagram of FIG. 20 is merely an example and is a simplified diagram that does not necessarily show all electrical components of the valve assembly 100. FIG. 20 shows a single switch 2010 and a single SMA wire 222 associated with a respective SMA actuator assembly 170. However, as indicated by other figures, the valve assembly 100 may include additional actuator assemblies 170 that each include their own switch 2010 and SMA wire 222 that are connected to different respective pins of the connector 124. FIG. 20 shows the first contact 254 as receiving power from the connector 124. However, in some instances, the first contact 254 may alternatively receive power from another power source (e.g., a power source included within the valve assembly 100 and / or dedicated to the valve assembly 100). In some instances, at least some of the electrical components shown in thediagram 2000 (e.g., the connector 124, the switching element 2015, etc.) are located on and / or electrically coupled to the PCB 186.

[0071] In some embodiments, the switching element 2015 (and its connection to the electrical path including the contacts 254 and 250) may not be present (e.g., the switch 2010 may merely include the switch 242). Rather, a single pin of the connector 124 may be electrically coupled in parallel to the SMA wire 222 and to the first contact 254. In such embodiments, a voltage may be applied to the pin by the control system / energy source 2005 to provide power to the SMA wire 222 and open / actuate the actuator assembly 170. In other words, when the energy source 2005 initially provides power to the SMA wire 222, the current flows to the SMA wire 222 since the contacts 254 and 250 are in the unactuated position due to the SMA wire 222 being at room temperature and in an extended state that does not oppose the bias force from the resilient member 218 on the plunger 190. As power is continued to be provided to the SMA wire 222, the SMA wire 222 contracts and causes the plunger 190 to move toward the first contact 254 to eventually move / push the first contact 254 into contact with the second contact 250 (i.e., the actuated position of the contacts 254 and 250). In response to the contacts 254 and 250 being in the actuated position, the current from the pin of the connector 124 begins to travel through the short circuit connection caused by the actuated contacts 254 and 250 since the resistance of the short circuit connection is significantly lower than the resistance of the SMA wire 222 (although a very small amount of current may still travel through the SMA wire 222). Because the SMA wire 222 is no longer powered (or is only powered at a very low level), its temperature decreases. The decreased temperature causes expansion of the SMA wire 222 and a lessening of the actuation force. Accordingly, the bias force of the resilient member 218 moves the plunger 190 back toward the exhaust passage 178, which allows the first contact 254 to be biased away from (i.e., out of contact with) the second contact 250 (i.e., the unactuated position of the contacts 254 and 250). In response to the contacts 254 and 250 being in the unactuated position, an open circuit is created between the contacts 254 and 250, and the current (i.e., all current from or the majority of the current) from the pin of the connector 124 again begins to travel to the SMA wire 222 assuming that the energy source 2005 is still applying power to the pin of the connector 124. Accordingly, oscillation of the contacts 254 and 250 between an open position and a closed position may occur without the use of the switching element 2015 in at least the above-explained embodiment.

[0072] As explained previously herein, the oscillation of the contacts 254 and 250 of the switch 2010 causes the power from the energy source 2005 that is provided to the switch 2010 and / or the contacts 250, 254 to be provided to the SMA wire 222 in an oscillating manner based on whether the contacts 254 and 250 are in the actuated position or the unactuated position. FIG. 21 illustrates a flowchart of a manner in which the power provided to the SMA wire 222 is controlled to oscillate according to the oscillation of the contacts 254 and 250 of the switch 2010.

[0073] At block 2105, the SMA wire 222 receives power from the energy source 2005 when the contacts 254 and 250 are in the unactuated position (i.e., not contacting each other). At block 2110, the SMA wire 222 actuates / moves (e.g., contracts) and moves the plunger 190 away from its respective fluid port (e.g., exhaust passage 178).

[0074] At block 2115, when the plunger 190 has not moved a predetermined distance to move the contacts 254 and 250 into the actuated position, the SMA wire 222 continues to receive power (at block 2105) and continues to contract (at block 2110). On the other hand, at block 2115, when the plunger 190 moves the predetermined distance to move the contacts 254 and 250 into the actuated position due to the actuation force exerted by the SMA wire 222 when the SMA wire 222 is powered, power is prevented from being provided to the SMA wire 222 (i.e., current no longer flows to the SMA wire 222) in response to the contacts 254 and 250 being actuated (at block 2120). For example, the switch 2010 prevents power from being provided to the SMA wire 222 (e.g., the switching element 2015 disconnects the SMA wire 222 from the energy source 2005). As noted above, in some embodiments (e.g., embodiments without the switching element 2015), a very small amount of current may still flow to the SMA wire 222 at block 2120. However, this very small amount of current is inconsequential because it is so small that the temperature of the SMA wire 222 is still able to cool / lower to allow the oscillation functionality of the actuator assembly 170 described herein. Accordingly, such a very small / inconsequential amount of current flowing to the SMA wire 222 may be considered to be power no longer being provided (i.e., current no longer flowing) to the SMA wire 222 (at block 2120).

[0075] At block 2125, the SMA wire 222 moves (e.g., expands) back toward an unpowered shape of the SMA wire 222 which allows the bias force from the resilient member 218 to move the plunger 190 back toward the fluid port (e.g., exhaust passage 178) to causethe contacts 254 and 250 to return to the unactuated position in response to no longer receiving power from the energy source 2005.

[0076] At block 2130, when the plunger 190 has not moved far enough toward the fluid port (e.g., exhaust passage 178) to cause the contacts 254 and 250 to change to the unactuated position, the switch 2010 continues to prevent power from being provided from the energy source 2005 to the SMA wire 222 (e.g., the switching element 2015 continues to disconnect the power from the energy source 2005 to the SMA wire 222) (at block 2120) and the SMA wire 222 continues to expand which allows the plunger 190 to continue to move toward the fluid port (e.g., exhaust passage 178). On the other hand, at block 2130, when the plunger 190 has moved far enough toward the fluid port (e.g., exhaust passage 178) to cause the contacts 254 and 250 to change to the unactuated position, the switch 2010 (e.g., the switching element 2015) re-allows the energy source 2005 to provide power to the SMA wire 222 in response to the contacts 254 and 250 returning to the unactuated position (at block 2105).

[0077] As indicated by FIG. 21, the method 2100 may repeat indefinitely while the energy source 2005 is providing power to a respective actuator assembly 170 (e.g., via a pin of the connector 124). As explained previously herein, such repetition of the method 2100 (a) limits the movement of the SMA wire 222 when power is applied to the SMA wire 222 (e.g., to prevent over-actuation) and (b) maintains the plunger 190 in the open position to allow the fluid to flow through the fluid port (e.g., exhaust passage 178) as long as power is being provided from the energy source 2005 to the respective actuator assembly 170. In other words, the actuator assembly 170 provides an instinct valve by self-regulating itself to limit the movement of the SMA wire 222 when power is applied to the SMA wire 222 (e.g., to prevent over-actuation). Due to this self-regulation, the same voltage / power may be provided to the actuator assembly 170 regardless of ambient temperature, age of the actuator assembly 170, SMA wire manufacturing tolerance, etc., and the actuator assembly 170 will function as desired. Thus, the amount of voltage / power provided to the respective actuator assembly 170 does not need to be adjusted depending on variables such as ambient temperature, age of the actuator assembly 170, SMA wire manufacturing tolerance, etc. that may effect how much and / or how quickly the SMA wire 222 expands and / or contracts. In other words, in some instances, the self-regulating actuator assembly 170 may function regardless of how much and / or how quickly the SMA wire 222 expands and / or contracts andregardless of whether how much and / or how quickly the SMA wire 222 expands and / or contracts changes over time and / or in different operating environments.

[0078] FIGS 10-17 illustrate a valve module 1100 (i.e., valve assembly 1100) in accordance with another embodiment. The valve module 1100 is similar to the valve module 100 with like components given like reference numerals plus “1000”. The main difference being that the valve module 1100 includes four work ports 1130 leading to four air bladders, while the valve module 100 had two work ports 130 leading to two air bladders. Identical components (e.g., SMA actuator assemblies 1170, lever actuators 1262, PCB 1186) are not described for sake of brevity. The valve module 1100 is described in further detail below.

[0079] With reference to FIGS. 10 and 11, the valve module 1100 includes a main housing 1104 including a top cover 1118 and a bottom cover 1122 that are laser welded to the main housing 1104. The main housing 1104 includes a pressure port 1134 connected to a pneumatic pump and a plurality of work ports 1130 connected to air bladders. A supply manifold 1154 receives an airflow path AF after entering the pressure port 1134 and distributes the pressurized air across two check valves 1162, which for the sake of explaining the travel path divides into two airflow paths AF1 and AF2 (FIG. 12). Each work port 1130 is fluidly connected to an associated actuator chamber 1150. Each actuator chamber 1150 supports an SMA actuator assembly 1170 and a lever actuator 1262, which cooperate to direct the airflow path AF towards specific work ports 1130. The SMA actuator assemblies 1170 and the lever actuators 1262 also cooperate to discharge air through an exhaust manifold 1126 to atmosphere. The exhaust manifold 1126 is downstream of the actuator chambers 1150 and is adjacent the bottom cover 1122. The bottom cover 1122 includes a plurality of ports 1182 to exhaust the pressurized air to atmosphere along the airflow path AF.

[0080] With reference to FIGS. 12 and 13, the SMA actuator assemblies 1170 include four SMA actuator assemblies 1170a-d, with each being disposed in respective actuator chambers 1150a-d, as shown in FIG. 11. There are also four lever actuators 1262a-d interfaced with corresponding SMA actuator assemblies 1170a-d. The actuator chambers 1150a, 1150b are fluidly connected together and the actuator chambers 1150c, 1150d are fluidly connected together. Furthermore, the SMA actuator assembly 1170a and the SMA actuator assembly 1170d are responsible for either inflating or deflating the air bladders, whereas the SMA actuator assembly 1170b and the SMA actuator assembly 1170c areresponsible for selecting the air bladder. Air bladders B1-B4 are connected to work ports 1130a-d.

[0081] With continued reference to FIGS. 12 and 13, downstream of the check valves 1162 is a first pair of transfer manifolds 1166a (FIG. 13). The transfer manifolds 1166a are in fluid communication with the check valves 1162 via transfer passages 1168. The pair of transfer manifolds 1166a is disposed between the supply manifold 1154 and the actuator chambers 1150 along the airflow path AF1 and AF2. The transfer manifolds 1166a direct the airflow path AF towards the work ports 1130b, 1130c. There is a second pair of transfer manifolds 1166b (FIG. 13) that, when open, redirect the airflow path AF toward the work ports 1130a, 1130d.

[0082] In operation, to fill the air bladders Bl and B4, for example, an external pump (not shown) is fluidly connected to pressure port 1134 is turned on to create the airflow path AF through the valve module 1100 via the pressure port 1134 and supply manifold 1154 (FIG. 12). After the pressurized air passes beyond the check valves 1162, the airflow path AF divides into two airflow paths AF1, AF2 that each travel through one of the first transfer manifolds 1166a. At this point, the airflow path AF1 enters the actuator chamber 1150a via the fill passage 1174a and the airflow path AF2 enters the actuator chamber 1150d via the fill passage 1174d. The fill passages 1174a, 1174d are, by default, open since the SMA actuator assemblies 1170a, 1170d are in the extended (or closed) positions. Similarly, the fill passages 1174b, 1174c in the actuator chambers 1150b, 1150c are also open by default. With the fill passages 1174a-d uncovered (FIG. 12), the airflow path AF1 transfers from the fill passage 1174a to the fill passage 1174b since actuator chambers 1150a, 1150b are fluidly connected, and the airflow path AF2 transfers from the fill passage 1174d to the fill passage 1174c since the actuator chambers 1150d, 1150c are fluid connected. As shown in FIG. 12, the airflow paths AF1, AF2 then travels through the second pair of transfer manifolds 1166b and exits the work ports 1130a, 1130d to inflate the air bladders Bl and B4.

[0083] With reference to FIGS. 14 and 15, if the air bladders B2 and B3 are desired to be inflated, the SMA actuator assemblies 1170b, 1170c are actuated (shown in FIG. 14) because they are responsible for the bladder selection. In the same manner as the valve module 100, when the SMA actuator assemblies 1170b, 1170c are energized and moved to the retracted position, the associated lever actuators 1262b, 1262c move to the closed position as a result, thus closing the fill passages 1174b, 1174c (FIG. 14) that lead to the work ports 1130a,1130d. At this point, the airflow paths AF1, AF2 opens toward the work ports 1130b, 1130c to inflate the air bladders B2 and B3. The check valves 1162 inhibit the air bladders B1-B4 from deflating.

[0084] With reference to FIGS. 16 and 17, when deflating the air bladders B1-B4, the SMA actuator assemblies 1170a, 1170d (shown in FIG. 16) are actuated because they are responsible for bladder inflation / deflation. In the same manner as the valve module 100, when the SMA actuator assemblies 1170a, 1170d are energized and moved to the retracted position, the exhaust passages 1178 open to allow the airflow AF1, AF2 to exhaust through the exhaust manifold 1126 (FIG. 17). Although FIGS. 16 and 17 only show the air bladders B2 and B3 being deflated, the air bladders Bl and B4 are deflated by moving the SMA actuator assemblies 1170b, 1170c to the extended position, which opens the fdl passages 1174b, 1174c, thereby connecting the work ports 1130a, 1130d to the actuator chambers 1150b, 1150c.

[0085] As explained previously herein, the valve assemblies 100, 1100 described herein may be fluidly coupled to (e.g., in fluid communication with) one or more bladders configured to be selectively filled with fluid as described herein. For example, the bladder(s) may be included in a seat (e.g., a seat in an automobile, an office chair, and / or the like) and may selectively receive pressurized air to increase seating comfort (e.g., by adjusting lumbar support and / or bolster support, and / or by providing massaging movements). The valve assemblies 100, 1100 described herein are merely examples. In some instances, the valve assemblies 100, 1100 may include different configurations and / or may include more or less actuator assemblies 170 and / or fluid ports (i.e., fluid passages). In some instances, the valve assemblies 100, 1100 may be configured to direct / control a different fluid besides pressurized air and / or may be used in other types of applications besides adjusting seating comfort in a seat. In some instances, the instinct valve design described herein may be used with any application with a linear movement actuator.

[0086] Various features and aspects of the present disclosure are set forth in the following claims.

Claims

CLAIMSWhat is claimed is:

1. An actuator assembly configured to cooperate with a housing to form a valve, the actuator assembly comprising: a support base attachable to the housing; a plunger arranged on the support base and including a seal element arranged at an end of the plunger; a resilient member configured to exert a bias force onto the plunger, wherein the bias force, when unopposed, biases the plunger in a closed position that causes the seal element to seal a fluid port to prevent a flow of fluid through the fluid port; a shape memory alloy actuator configured to exert an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source, wherein the actuation force opposes the bias force from the resilient member and moves the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port; and a switch including contacts configured to be actuated in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloy actuator, wherein the switch is configured to prevent power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated; wherein the contacts of the switch are configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source to the switch, and wherein oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

2. The actuator assembly of claim 1, wherein the shape memory alloy actuator is configured to contract in response to receiving power from the energy source; and wherein the oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in the range of movement that prevents over-contraction of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in theopen position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

3. The actuator assembly of claim 1, wherein the oscillation of the contacts of the switch is caused by:(a) the contacts being actuated to the actuated position in response to the plunger moving the predetermined distance due to the actuation force exerted by the shape memory alloy actuator when the shape memory alloy actuator is powered;(b) the switch preventing power from being provided to the shape memory alloy actuator in response to the contacts being actuated;(c) the shape memory alloy actuator moving back toward an unpowered shape of the shape memory alloy actuator to allow the bias force to move the plunger back toward the fluid port to cause the contacts to return to the unactuated position in response to the shape memory alloy actuator no longer receiving power from the energy source;(d) the switch re-allowing the energy source to provide power to the shape memory alloy actuator in response to the contacts returning to the unactuated position; and(e) repeating steps (a) through (d).

4. The actuator assembly of claim 1, wherein the oscillation of the contacts of the switch causes the power from the energy source to be provided to the shape memory alloy actuator in an oscillating manner based on whether the contacts are in the actuated position or the unactuated position.

5. The actuator assembly of claim 1, wherein the contacts include a first contact and a second contact configured to be located a distance from each other so as to cause an open circuit between the first contact and the second contact in the unactuated position to prevent current flow between the first contact and the second contact; and wherein the first contact is configured to be moved, by the plunger due to the actuation force exerted by the shape memory alloy actuator, to contact the second contact so as to cause a closed circuit between the first contact and the second contact in the actuated position to allow current flow between the first contact and the second contact.

6. The actuator assembly of claim 5, wherein the switch includes a switching element electrically coupled to the first contact, the second contact, or both the first contact and the second contact, wherein the switching element is configured to: allow current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the unactuated position; and prevent current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the actuated position.

7. The actuator assembly of claim 1, wherein the fluid port is fluidly coupled to a bladder configured to be selectively filled with the fluid, wherein the bladder is located in a seat.

8. A method of operating an actuator assembly, the method comprising: exerting, with a resilient member, a bias force onto a plunger, wherein the bias force, when unopposed, biases the plunger in a closed position that causes a seal element arranged at an end of the plunger to seal a fluid port to prevent a flow of fluid through the fluid port; exerting, with a shape memory alloy actuator, an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source, wherein the actuation force opposes the bias force from the resilient member and moves the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port; actuating contacts of a switch in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloy actuator; preventing, with the switch, power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated; and oscillating the contacts of the switch between an actuated position and an unactuated position while power is being provided from the energy source to the switch, wherein oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

9. The method of claim 8, wherein exerting the actuation force onto the plunger includes contracting, by the shape memory alloy actuator, in response to receiving power from the energy source; and wherein the oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in the range of movement that prevents over-contraction of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

10. The method of claim 8, wherein oscillating the contacts of the switch is caused by:(a) the contacts being actuated to the actuated position in response to the plunger moving the predetermined distance due to the actuation force exerted by the shape memory alloy actuator when the shape memory alloy actuator is powered;(b) the switch preventing power from being provided to the shape memory alloy actuator in response to the contacts being actuated;(c) the shape memory alloy actuator moving back toward an unpowered shape of the shape memory alloy actuator to allow the bias force to move the plunger back toward the fluid port to cause the contacts to return to the unactuated position in response to the shape memory alloy actuator no longer receiving power from the energy source;(d) the switch re-allowing the energy source to provide power to the shape memory alloy actuator in response to the contacts returning to the unactuated position; and(e) repeating steps (a) through (d).

11. The method of claim 8, wherein oscillating the contacts of the switch causes the power from the energy source to be provided to the shape memory alloy actuator in an oscillating manner based on whether the contacts are in the actuated position or the unactuated position.

12. The method of claim 8, wherein the contacts include a first contact and a second contact configured to be located a distance from each other so as to cause an open circuit between the first contact and the second contact in the unactuated position to prevent current flow between the first contact and the second contact; andwherein actuating the contacts of the switch includes the first contact being moved, by the plunger due to the actuation force exerted by the shape memory alloy actuator, to contact the second contact so as to cause a closed circuit between the first contact and the second contact in the actuated position to allow current flow between the first contact and the second contact.

13. The method of claim 12, wherein the switch includes a switching element electrically coupled to the first contact, the second contact, or both the first contact and the second contact, wherein the method further comprises: allowing, with the switching element, current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the unactuated position; and preventing, with the switching element, current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the actuated position.

14. The method of claim 8, wherein the fluid port is fluidly coupled to a bladder configured to be selectively filled with the fluid, wherein the bladder is located in a seat.

15. A fluid flow control system comprising: a plurality of bladders configured to be selectively filled with a fluid; and a valve assembly in fluid communication with the plurality of bladders, the valve assembly including a housing and a plurality of actuator assemblies that are configured to cooperate with the housing to form a plurality of valves, wherein each actuator assembly includes: a support base attachable to the housing, a plunger arranged on the support base and including a seal element arranged at an end of the plunger, a resilient member configured to exert a bias force onto the plunger, wherein the bias force, when unopposed, biases the plunger in a closed position that causes the seal element to seal a fluid port to prevent a flow of fluid through the fluid port; a shape memory alloy actuator configured to exert an actuation force onto the plunger when the shape memory alloy actuator is powered by an energy source, wherein the actuation force opposes the bias force from the resilient member andmoves the plunger to an open position that causes the seal element to be moved away from the fluid port to allow the flow of the fluid through the fluid port; and a switch including contacts configured to be actuated in response to the plunger being moved a predetermined distance by the actuation force exerted by the shape memory alloy actuator, wherein the switch is configured to prevent power from being provided to the shape memory alloy actuator from the energy source when the contacts are actuated; wherein the contacts of the switch are configured to oscillate between an actuated position and an unactuated position while power is being provided from the energy source to the switch, and wherein oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in a range of movement that limits movement of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

16. The fluid flow control system of claim 15, wherein the shape memory alloy actuator is configured to contract in response to receiving power from the energy source; and wherein the oscillation of the contacts of the switch between the actuated position and the unactuated position causes the shape memory alloy actuator to expand and contract in the range of movement that prevents over-contraction of the shape memory alloy actuator when power is applied to the shape memory alloy actuator and that maintains the plunger in the open position to allow the fluid to flow through the fluid port as long as power is being provided from the energy source.

17. The fluid flow control system of claim 15, wherein the oscillation of the contacts of the switch is caused by:(a) the contacts being actuated to the actuated position in response to the plunger moving the predetermined distance due to the actuation force exerted by the shape memory alloy actuator when the shape memory alloy actuator is powered;(b) the switch preventing power from being provided to the shape memory alloy actuator in response to the contacts being actuated;(c) the shape memory alloy actuator moving back toward an unpowered shape of the shape memory alloy actuator to allow the bias force to move the plunger back toward thefluid port to cause the contacts to return to the unactuated position in response to the shape memory alloy actuator no longer receiving power from the energy source;(d) the switch re-allowing the energy source to provide power to the shape memory alloy actuator in response to the contacts returning to the unactuated position; and(e) repeating steps (a) through (d).

18. The fluid flow control system of claim 15, wherein the contacts include a first contact and a second contact configured to be located a distance from each other so as to cause an open circuit between the first contact and the second contact in the unactuated position to prevent current flow between the first contact and the second contact; and wherein the first contact is configured to be moved, by the plunger due to the actuation force exerted by the shape memory alloy actuator, to contact the second contact so as to cause a closed circuit between the first contact and the second contact in the actuated position to allow current flow between the first contact and the second contact.

19. The fluid flow control system of claim 18, wherein the switch includes a switching element electrically coupled to the first contact, the second contact, or both the first contact and the second contact, wherein the switching element is configured to: allow current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the unactuated position; and prevent current flow from the energy source to the shape memory alloy actuator when the first contact and the second contact are in the actuated position.

20. The fluid flow control system of claim 15, wherein the plurality of bladders is located in a seat and is configured to selectively receive pressurized air to increase seating comfort by at least one of a group consisting of adjusting lumbar support, adjusting bolster support, providing massaging movements, and combinations thereof.

21. A valve module for selectively allowing airflow from a pump to one or more air bladders, the valve module comprising: a main housing; a pressure port configured to receive the airflow from the pump; a plurality of work ports in fluid communication with the one or more air bladders;a first check valve and a second check valve disposed within the main housing and downstream of the pressure port, the first and second check valves selectively allow the airflow to pass therethrough; a first actuator chamber in fluid communication with the first check valve and including a first shape memory alloy (SMA) actuator; a second actuator chamber in fluid communication with the second check valve and including a second shape memory alloy (SMA) actuator; and an exhaust manifold disposed downstream from both the first actuator chamber and the second actuator chamber, the exhaust manifold configured to discharge the airflow to a surrounding atmosphere upon energizing either the first SMA actuator or the second SMA actuator.

22. The valve module of claim 21, further comprising a printed circuit board that is in electrical communication with the first SMA actuator and the second SMA actuator.

23. The valve module of claim 22, wherein the main housing further includes a top cover and a bottom cover, wherein the top cover and the main housing form an airtight seal to enclose the first and second SMA actuators in the first and second actuator chambers, respectively, and wherein the bottom cover and the main housing form an airtight seal to enclose the printed circuit board.

24. The valve module of claim 22, wherein the main housing further includes a base, wherein the first and second SMA actuators are supported on one side of the base and the printed circuit board is supported on an opposite side of the base.

25. The valve module of claim 24, further comprising a fill passage disposed through the base in each the first and second actuator chambers, which allows the airflow to travel from the first and second check valves to the first and second actuator chambers, respectively.

26. The valve module of claim 25, further comprising a follower mechanism that is interfaced with each SMA actuator, wherein the follower mechanism is biased towards and selectively closes the fill passage.

27. The valve module of claim 26, wherein each follower mechanism includes a shoulder that is biased towards and abuts against a finger on each SMA actuator, such that each follower mechanism moves in response to movement of its corresponding SMA actuator.

28. The valve module of claim 27, wherein each SMA actuator includes a plunger that is biased toward an extended position via a spring, each SMA actuator further including a wire that, when energized, biases the plunger towards a retracted position against a bias of the spring.

29. The valve module of claim 28, wherein the plunger defines a longitudinal axis along which the plunger moves between the extended position and the retracted position, where the finger extends along a direction perpendicular to the longitudinal axis.

30. The valve module of claim 28, wherein the follower mechanism opens the fill passage when its corresponding SMA actuator is in the extended position and closes the fill passage when its corresponding SMA actuator is in the retracted position.

31. The valve module of claim 21, wherein the first and second check valves inhibit the airflow from escaping the one or more air bladders, and wherein the first and second SMA actuators enable the airflow to be discharged from the one or more air bladders.

32. The valve module of claim 31, wherein the first and second check valves are upstream of the first and second SMA actuators.

33. The valve module of claim 21, wherein the airflow being introduced through the pressure port travels beyond the first and second check valves and is introduced directly into the one or more air bladders without actuating either the first SMA actuator or the second SMA actuator.

34. A valve module for selectively allowing airflow from a pump to pass to one or more air bladders, the valve module comprising: a main housing; a pressure port configured to receive the airflow from the pump; a plurality of work ports in fluid communication with the one or more air bladders;a first check valve and a second check valve disposed within the main housing and downstream of the pressure port, the first and second check valves configured to inhibit the airflow from exhausting from the one or more air bladders; a first shape memory alloy (SMA) actuator downstream the first check valve; and a second shape memory alloy (SMA) actuator downstream the second check valve, wherein the airflow is introduced into the one or more air bladders without actuating the first SMA actuator or the second SMA actuator.

35. The valve module of claim 34, wherein the airflow is discharged from the one or more air bladders to atmosphere upon actuating the first SMA actuator and the second SMA actuator.

36. The valve module of claim 34, further comprising a printed circuit board that is in electrical communication with the first SMA actuator and the second SMA actuator.

37. The valve module of claim 36, wherein the main housing further includes a top cover and a bottom cover, wherein the top cover and the main housing form an airtight seal to enclose the first and second SMA actuators, and wherein the bottom cover and the main housing form an airtight seal to enclose the printed circuit board.

38. The valve module of claim 34, further comprising a first fill passage and a second fill passage that receives the airflow that passes beyond the first check valve and the second check valve, respectively, and directs the airflow to the one or more air bladders.

39. The valve module of claim 38, further comprising a first follower mechanism that is interfaced with the first SMA actuator and a second follower mechanism that is interfaced with the second SMA actuator, wherein the first and second follower mechanisms close the first and second fill passages when the first and second SMA actuators are actuated.

40. The valve module of claim 39, wherein the first follower mechanism and the second follower mechanism are biased toward and follow movement of the first SMA actuator and the second SMA actuator, respectively.

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