摘要:
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.
摘要:
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.
摘要:
A microvalve device for controlling fluid flow in a fluid circuit. The microvalve device comprises a body having a cavity formed therein. An electronically controlled automatic transmission, comprising of an input shaft; an output shaft; a plurality of gears providing driving connection between the input shaft and the output shaft; one of a hydraulically operated brake band and a hydraulically operated clutch which is operable to effect a change in the gear reduction provided by the gears between the input shaft and the output shaft; a source of pressurized hydraulic fluid; and a microvalve device selectively operable to control passage of pressurized hydraulic fluid from the source to the one of a hydraulically operated brake band and a hydraulically operated clutch to operate the one of a hydraulically operated brake band and a hydraulically operated clutch.
摘要:
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. Thus, both actuation and displacement of the displaceable member are in the plane of the layer.
摘要:
A vehicular anti-lock brake system control unit having a control valve includes a housing with a control valve bore therein. The control valve includes a sleeve with a moveable armature, and a coil surrounding the sleeve for moving the armature. The control valve also includes a valve body having an outer end attached to the sleeve and an inner end seated within the control valve bore of the housing. The valve body has an outer diameter no greater than the outer diameter of the coil such that minimum spacing between multiple control valves in the control unit is not limited by the outer diameter of the valve body, a construction which is facilitated by constructing the flux ring as a component separate from the valve housing and, in one form, adapted to be a part of the coil assembly carried by a separate electric control module.
摘要:
An improved electro-hydraulic brake system having an electrically powered normal source of pressurized hydraulic brake fluid, and a manually powered backup source of pressurized hydraulic brake fluid to all four of the vehicle brakes in the event of failure of the normal source. During normal braking, fluid from the backup source is redirected from the vehicle brakes to a pedal simulator. The brake system of the invention further diverse arrangements for providing braking in the event of a failure of the normal source of pressurized fluid. The brake circuit for the front wheels are provided with relatively low cost fluid separator units, while the rear brake circuit is not.
摘要:
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. Thus, both actuation and displacement of the displaceable member are in the plane of the layer.
摘要:
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.
摘要:
An antilock braking system having a permanent reduced flow bypass passageway provided in parallel with the isolation valve to reduce the feedback to the brake pedal during an antilock mode of operation. In the preferred embodiment, the permanent fluid bypass passageway is provided internal to the isolation valve. The fluid bypass passageway connects the input fluid passageway to the output passageway in parallel with the valve member controlling the primary fluid flow through the isolation valve.
摘要:
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. Thus, both actuation and displacement of the displaceable member are in the plane of the layer.