Abstract: A refrigeration system includes a compressor, a condenser fluidly connected to the compressor, an evaporator fluidly connected to the condenser and the compressor, such that fluid may flow from the compressor through the condenser, through the evaporator, and again through the compressor. An expansion device is fluidly connected between the condenser and the evaporator, and a micro-expansion valve is also connected between the condenser and the evaporator.

Abstract: A microvalve includes a first plate having an inner surface, a recessed region provided within the inner surface, a normally open fluid port and a normally closed fluid port provided within the recessed region. A first sealing structure extends about the normally open fluid port, and a second sealing structure extends about the normally closed fluid port. A second plate defines a non-movable portion and a movable portion. A surface of the non-movable portion abuts the inner surface of the first plate, the non-movable portion having an opening formed therethrough. The movable portion is formed within the opening, has an axis, and defines a displaceable member connected to the non-movable portion by a convoluted spring formed in the opening.

Abstract: A microvalve includes a first plate having a surface, a recessed region provided within the surface, a fluid port provided within the recessed region, and a sealing structure extending about the fluid port. A second plate defines a non-movable portion and a movable portion, a surface of the non-movable portion abutting the surface of the first plate, the non-movable portion having first and second openings formed therethrough. The movable portion is formed within the first opening and has an axis, the movable portion defining a displaceable member connected to the non-movable portion by a convoluted spring formed in a second opening.

Abstract: A microvalve includes a first plate having a surface, a recessed region provided within the surface, a fluid port provided within the recessed region, and a sealing structure extending about the fluid port. A second plate defines a non-movable portion and a movable portion formed within the first opening and having an axis. A surface of the non-movable portion abuts the surface of the first plate, the non-movable portion having first and second openings formed therethrough. The first opening has a notch formed in each of two longitudinally extending side walls thereof. The movable portion defines a displaceable member connected to the non-movable portion by a convoluted spring formed in a second opening. The displaceable member has a tab extending outwardly from each of two longitudinally extending side walls thereof, each tab positioned within one of the notches.

Abstract: A device is disclosed that may include a spool valve having a first connector and a second connector and a spool movable for controlling flow between the first connector and the second connector, regardless of direction of flow through the spool valve. A pilot valve having an inlet and an outlet develops a command pressure. A feedback circuit having an inlet and an outlet develops a feedback pressure. The spool valve may be responsive to the command pressure and the feedback pressure. A fluid rectifier circuit is provided to connect the higher pressure of the first connector and second connector to the pilot valve inlet and feedback circuit inlet, and connect the other of the first connector and second connector to the pilot valve outlet and feedback circuit outlet.

Abstract: A microvalve includes a base plate having a surface defining an actuator cavity. A venting groove extends from a first cavity portion of the actuator cavity having a dead end region to a second cavity portion of the actuator cavity having a structure that can vent air from the microvalve. A cover plate includes a surface having an actuator cavity provided therein that includes a first cavity portion having a dead end region and a second cavity portion having a structure that can vent air from the microvalve. An intermediate plate includes a displaceable member that is disposed within the actuator cavity for movement between a closed position, wherein the displaceable member prevents fluid communication through the microvalve, and an opened position, wherein the displaceable member does not prevent fluid communication through the microvalve.

Abstract: A microvalve includes a first plate having a surface, a recessed region provided within the surface, a fluid port provided within the recessed region, and a sealing structure extending about the fluid port. A second plate defines a non-movable portion and a movable portion, a surface of the non-movable portion abutting the surface of the first plate, the non-movable portion having first and second openings formed therethrough. The movable portion is formed within the first opening and has an axis, the movable portion defining a displaceable member connected to the non-movable portion by a convoluted spring formed in a second opening.

Abstract: A microvalve includes a first plate having an inner surface, a recessed region provided within the inner surface, a normally open fluid port and a normally closed fluid port provided within the recessed region. A first sealing structure extends about the normally open fluid port, and a second sealing structure extends about the normally closed fluid port. A second plate defines a non-movable portion and a movable portion. A surface of the non-movable portion abuts the inner surface of the first plate, the non-movable portion having an opening formed therethrough. The movable portion is formed within the opening, has an axis, and defines a displaceable member connected to the non-movable portion by a convoluted spring formed in the opening.

Abstract: A microvalve includes a first plate having a surface, a recessed region provided within the surface, a fluid port provided within the recessed region, and a sealing structure extending about the fluid port. A second plate defines a non-movable portion and a movable portion formed within the first opening and having an axis. A surface of the non-movable portion abuts the surface of the first plate, the non-movable portion having first and second openings formed therethrough. The first opening has a notch formed in each of two longitudinally extending side walls thereof. The movable portion defines a displaceable member connected to the non-movable portion by a convoluted spring formed in a second opening. The displaceable member has a tab extending outwardly from each of two longitudinally extending side walls thereof, each tab positioned within one of the notches.

Abstract: A refrigeration system includes a compressor, a condenser fluidly connected to the compressor, an evaporator fluidly connected to the condenser and the compressor, such that fluid may flow from the compressor through the condenser, through the evaporator, and again through the compressor. An expansion device is fluidly connected between the condenser and the evaporator, and a micro-expansion valve is also connected between the condenser and the evaporator.

Abstract: An arrangement includes a housing defining a first and second ports. A first passageway provides communication between the ports; a second passageway provides communication with the first port. An element is disposed in the housing and positioned by a balance of forces, the element is positionable to throttled positions for controlling flow through the first passageway in a first direction and to an open position to permit unrestricted flow in a second direction. A check valve is disposed in the second passageway for preventing flow therein from the first port when pressure in the first port is greater than pressure in the second port, and permitting flow through the second passageway to the first port when pressure in the first port is less than the pressure in the second port thereby affecting the balance of forces acting on the element so the element is urged toward the fully open position.

Abstract: An arrangement includes a housing defining a first and second ports. A first passageway provides communication between the ports; a second passageway provides communication with the first port. An element is disposed in the housing and positioned by a balance of forces, the element is positionable to throttled positions for controlling flow through the first passageway in a first direction and to an open position to permit unrestricted flow in a second direction. A check valve is disposed in the second passageway for preventing flow therein from the first port when pressure in the first port is greater than pressure in the second port, and permitting flow through the second passageway to the first port when pressure in the first port is less than the pressure in the second port thereby affecting the balance of forces acting on the element so the element is urged toward the fully open position.

Abstract: A microvalve includes a base plate including a surface, a recessed area provided within the surface, a first fluid port provided within the recessed area, and a first sealing structure extending about the first fluid port. The microvalve also includes a cover plate including a surface, a recessed area provided within the surface, a second fluid port provided within the recessed area, and a second sealing structure extending about the second fluid port. An intermediate plate is disposed between the base plate and the cover plate and includes a displaceable member that is movable between a closed position, wherein the displaceable member cooperates with the sealing structures to prevent fluid communication between the fluid ports, and an opened position, wherein the displaceable member does not cooperate with at least a portion of the sealing structures to prevent fluid communication between the fluid ports.

Abstract: A microvalve includes a base plate having a surface defining an actuator cavity. A venting groove extends from a first cavity portion of the actuator cavity having a dead end region to a second cavity portion of the actuator cavity having a structure that can vent air from the microvalve. A cover plate includes a surface having an actuator cavity provided therein that includes a first cavity portion having a dead end region and a second cavity portion having a structure that can vent air from the microvalve. An intermediate plate includes a displaceable member that is disposed within the actuator cavity for movement between a closed position, wherein the displaceable member prevents fluid communication through the microvalve, and an opened position, wherein the displaceable member does not prevent fluid communication through the microvalve.

Abstract: A device is disclosed that may include a spool valve having a first connector and a second connector and a spool movable for controlling flow between the first connector and the second connector, regardless of direction of flow through the spool valve. A pilot valve having an inlet and an outlet develops a command pressure. A feedback circuit having an inlet and an outlet develops a feedback pressure. The spool valve may be responsive to the command pressure and the feedback pressure. A fluid rectifier circuit is provided to connect the higher pressure of the first connector and second connector to the pilot valve inlet and feedback circuit inlet, and connect the other of the first connector and second connector to the pilot valve outlet and feedback circuit outlet.

Abstract: A MEMS device is disclosed having a single microvalve actuator for controlling multiple microvalves. Exemplary embodiments include a MEMS device including two microvalves formed on a beam positioned by an actuator, the two microvalves controlling separate flow paths between two separate pairs of ports; a device with a two-way pilot operated microvalve and a four-way pilot microvalve for controlling the two-way pilot operated microvalve; a device with two three-way microvalves actuated by a common microvalve actuator; and a two-way microvalve with a moveable microvalve element and a feedback port formed in the moveable element operable to regulate the pressure on an end of the moveable element relative to the movement of the moveable element between the first position and the second position. Also disclosed is a MEMS device including a beam with a plurality of apertures formed therein, resulting in a mass reduction of at least 10 percent.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistivity and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: A microvalve device includes a pilot valve and a pilot operated valve. The pilot valve includes a first layer having openings and a second layer having a chamber in communication with the openings, and a movable member for controlling fluid flow. The pilot operated valve includes three plates. Two the openings, and pressure apply and release channels in communication with a spool portion of the pilot operated valve. The spool is movable to allow from a second fluid source to a load. The third plate includes a first source port in communication with a first fluid, the pressure apply and release channel, one of the first plate ports, one of the openings, a first port in communication with a first reservoir, a second port is in communication with the second fluid source and a load port in communication with a load.

Abstract: A device is disclosed for controlling a variable displacement compressor. The device comprises a microvalve operated control valve. A microvalve device for controlling fluid flow and a micro spool valve for use as a microvalve are also disclosed.

Abstract: In a method of controlling an actuator of a microvalve, a controller is provided for supplying a voltage to the actuator. The controller provides an initial voltage to the actuator which is effective to actuate the microvalve. Then, the controller provides a pulsed voltage to the actuator which is effective to continue the actuation of the microvalve.