Abstract:
A microvalve device includes a microvalve pilot valve and a pilot operated valve. The microvalve pilot valve includes a first layer, a third layer having a plurality of openings formed therethrough, and a second layer positioned between the first and third layer. The second layer includes a chamber in fluid communication with the openings, and includes a movable member for selectively controlling fluid flow though the chamber and between the openings. The pilot operated valve includes a first plate, a third plate, and a second plate positioned between the first plate and the third plate. The first plate includes a plurality of ports in fluid communication with the openings of the microvalve, a pressure apply channel, and a pressure release channel. The second plate includes the pressure apply channel and the pressure release channel, both of the channels being in fluid communication with a spool portion of the pilot operated valve. The spool portion is selectively movable to allow flow from a second source of fluid to a load. The third plate includes a first source port in fluid communication with a first fluid source, the pressure apply channel, one of the first plate ports, and one of the microvalve openings. A first reservoir port of the third plate ports, and one of the microvalve openings. A first reservoir port of the third plate is in fluid communication with a first reservoir, the pressure release channel, one of the first plate ports, and one of the microvalve openings. A second source port of the third plate is in fluid communication with the second source of fluid. A load port of the third plate is in fluid communication with the load.
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 inlet and outlet ports. The second layer further defines an actuable 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 in the plane of the second layer while being very stiff out of the plane. Thus, both actuation and displacement of the displaceable member are in the plane of the layer.
Abstract:
The present invention provides a proportional microvalve (10) having a first (12), second (14) and third layer (16), and having high aspect ratio geometries. The first layer (12) defines a cavity (24) with inlet (20) and outlet (22) ports. The second layer (14), doped to have a low resistivity and bonded between the first (12) and third (16) layers, defines a cavity (24) having a flow area to permit fluid flow between the inlet (20) and outlet (22) ports. The second layer (14) further defines an actuatable displaceable member (26), and one or more thermal actuators (28, 30) for actuating the displaceable member (26) to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer (16) provides one wall of the cavity (24) and provides electrical contacts (32a, 32b, 34a, 34b) for electrically heating the thermally expandable actuators (28, 30). The thermal actuators (28, 30) and the displaceable member (26) have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer (14) while being very stiff out of the plane. Thus, both actuation and displacement of the displaceable member (26) are in the plane of the layer.
Abstract:
A thermopneumatic valve comprises a fluid channel plate (30) defining a fluid port. A diaphragm plate (28) is attached to the fluid channel plate. The diaphragm plate includes a displaceable diaphragm (44) to selectively obstruct the fluid port of the fluid channel plate. A thermal isolating heater (22) is connected to the diaphragm plate. The thermal isolating heater includes a thermal isolating heater body with a heating surface, a perimeter wall defining an extended axial cavity to confine a thermopneumatic working fluid (40) that is used to control the position of the displaceable diaphragm and a diaphragm obstruction structure (46) to limit the motion of the displaceable diaphragm into the extended axial cavity.
Abstract:
The present invention provides a proportional microvalve (10) having a first (12), second (14) and third layer (16), and having high aspect ratio geometries. The first layer (12) defines a cavity (24) with inlet (20) and outlet (22) ports. The second layer (14), doped to have a low resistivity and bonded between the first (12) and third (16) layers, defines a cavity (24) having a flow area to permit fluid flow between the inlet (20) and outlet (22) ports. The second layer (14) further defines an actuatable displaceable member (26), and one or more thermal actuators (28, 30) for actuating the displaceable member (26) to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer (16) provides one wall of the cavity (24) and provides electrical contacts (32a, 32b, 34a, 34b) for electrically heating the thermally expandable actuators (28, 30). The thermal actuators (28, 30) and the displaceable member (26) have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer (14) while being very stiff out of the plane. Thus, both actuation and displacement of the displaceable member (26) are in the plane of the layer.
Abstract:
Briefly described, the present invention is concerned with cooling heating bodies and/or heated fluid with synthetic jet actuators (10) in either open or closed systems. A first preferred embodiment of a cooling system of the present invention comprises a synthetic jet actuator directed to impinge directly on a heat producing (or heated) body. The synthetic jet actuator generates a synthetic jet stream (152) comprised of cool ambient fluid that impinges on the heated surface thereby cooling this surface. As an example, the heated surface/body could be a microchip array (155) in a microcomputer. After coming into contact with the heated surface, the fluid moves along the surface and is finally rejected to the ambient where it mixes and cools down. The synthetic jet may be incorporated into a modular unit that may be clipped onto a circuit board or other heat producing element to provide added, 'ad hoc' cooling. In another configuration, a synthetic jet stream actuator may be positioned, relative to the heated surface. In this embodiment, the flow (612) would be approximately tangential to a surface of heat producing body (608). This embodiment may further comprise a cyclical flow of the fluid jet, along the heated body and about a heat sink surface.