MICROVALVE DEVICE WITH IMPROVED FLUID ROUTING

• US 20100038576A1
• Filed: 08/12/2008
• Published: 02/18/2010
• Est. Priority Date: 08/12/2008
• Status: Active Grant

• Current Assignee: Dunan Microstaq, Inc. (Zhejiang Dun'an Artificial Environment Co., Ltd.)
• Original Assignee: Dunan Microstaq, Inc. (Zhejiang Dun'an Artificial Environment Co., Ltd.)
• Inventors: HUNNICUTT, HARRY A.
• Granted Patent: US 8,113,482 B2
• Time in Patent Office: Days
• US Class Current: 251/318
• CPC Class Codes: F16K 2099/0074 using photolithography, e.g. etching
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: Y10T 137/86622 Motor-operated
• CPC Class Codes: Y10T 137/8667 Reciprocating valve

Abstract

A microvalve device for controlling the supply of pressurized fluid to a load in a fluid circuit, and having multiple internal fluid conduits for providing pressure feedback.

Claims

1. A microvalve device comprising:

a body formed of multiple plates of material, an intermediate plate of the body having a cavity defined therein, the cavity having a longitudinal axis, at least a first port and a second port being defined in the body, which ports can communicate with the cavity;

a slider element movable within the cavity along the longitudinal axis of the cavity to selectively substantially block and unblock the first port, thereby selectively controlling fluid communication between the first port and the second port within the microvalve device, the slider element substantially sealing against the body to define a variable-volume region within the cavity, which variable-volume region varies in volume as the slider element moves; and

a fluid conduit being defined in a portion of the body, which portion of the body is not formed from the intermediate plate, the fluid conduit providing fluid communication between the second port and the variable-volume region regardless of the position of the slider element, the fluid conduit being at least one of non-linear and non-parallel to the longitudinal axis of the cavity.

2. The microvalve device of claim 1 further comprising:

a port plate forming a portion of the microvalve body, the port plate being fixed to the intermediate plate, at least one of the first port and the second port being defined by the port plate, the fluid conduit being defined in the port plate.

3. The microvalve device of claim 2 further comprising:

a cover plate forming a portion of the microvalve body, the cover plate being fixed to the intermediate plate.

4. The microvalve device of claim 3, wherein a second fluid conduit is defined in the cover plate, the second fluid conduit providing fluid communication between the second port and the variable-volume region regardless of the position of the slider element, the second fluid conduit being at least one of non-linear and non-parallel to the longitudinal axis of the cavity.

5. The microvalve device of claim 2, wherein a second fluid conduit is defined in the port plate, the second fluid conduit providing fluid communication between the second port and the variable-volume region regardless of the position of the slider element, the second fluid conduit being at least one of non-linear and non-parallel to the longitudinal axis of the cavity.

6. The microvalve device of claim 5, wherein the fluid conduit and the second fluid conduit are defined laterally outwardly of and spaced apart from the first port.

7. The microvalve device of claim 6 further comprising:

a cover plate forms a portion of the microvalve body, the cover plate being fixed to the intermediate plate;

a third fluid conduit defined in the cover plate, the third fluid conduit providing fluid communication between the second port and the variable-volume region regardless of the position of the slider element, the third fluid conduit being at least one of non-linear and non-parallel to the longitudinal axis of the cavity; and

a fourth fluid conduit defined in the cover plate, the fourth fluid conduit providing fluid communication between the second port and the variable-volume region regardless of the position of the slider element, the fourth fluid conduit being at least one of non-linear and non-parallel to the longitudinal axis of the cavity, the fourth fluid conduit being spaced apart from the third fluid conduit.

8. The microvalve device of claim 2 wherein the fluid conduit comprises a trench defined in the port plate, the trench having a first portion and a second portion which is not co-axial with the first portion.

9. The microvalve device of claim 8 wherein the first portion of the trench defines a linear path which is parallel to the longitudinal axis of the cavity.

10. The microvalve device of claim 8 wherein at least one of the first portion and the second portion of the trench defines an arcuate path.

11. The microvalve device of claim 2 wherein the fluid conduit comprises a trench in the port plate, the trench defining a linear path which is not parallel to the longitudinal axis of the cavity.

12. The microvalve device of claim 2, wherein the slider element comprises a first side portion, a second side portion, and at least one end portion which cooperates with the first and second side portions to define an opening through the slider element, which opening contains a volume in constant fluid communication with the second port and in constant fluid communication with the fluid conduit, the fluid conduit comprising a trench in the port plate which cooperates with the first side portion to form the fluid conduit between the variable volume region and the volume contained in the opening through the slider element.

13. A microvalve device comprising:

a body defining a first port and a second port and a fluid flow conduit between the first port and the second port;

a slider element movable within the body along a longitudinal axis to selectively block fluid communication through the fluid flow conduit between the first port and the second port, the slider element having an axial end face which cooperates with the body to define a variable-volume region, which variable-volume region varies in volume as the slider element moves; and

multiple fluid conduits being defined in at least one of the body and the slider element, each fluid conduit providing fluid communication between and the variable-volume region and one of the second port and a portion of the fluid flow conduit in continuous fluid communication with the second port, such that, in any position of the slider element, any fluid pressure existing at the second port is transmitted via the fluid conduit to exert a force on the axial end face of the slider element.

14. The microvalve device of claim 13, wherein the first port is disposed between the second port and the variable-volume region.

15. The microvalve device of claim 14, wherein each fluid conduit is at least one of non-linear and non-parallel to the longitudinal axis of the cavity.

16. The microvalve device of claim 13, wherein the body defines a third port, the microvalve device being configured as a 3-way microvalve, such that in a first position, the slider element permits fluid communication between the first and second ports and blocks fluid communication between the third and second ports, in a second position, the slider element permits fluid communication between the third and second ports and blocks fluid communication between the first and second ports, and in a third position, the slider element blocks fluid communication between the first and second ports and blocks fluid communication between the third and second ports.

17. The microvalve device of claim 16, wherein the axial end face is a first axial end face, the slider element having a second axial end face at an opposite end from the first axial end face, the second axial end face cooperating with the body to define a second variable-volume region, which second variable-volume region varies in volume as the slider element moves, and wherein the body defines a control port in fluid communication with the second variable-volume region.

18. The microvalve device of claim 17, further comprising a spring operatively coupling the body and the slider element.

19. The microvalve device of claim 13, wherein the axial end face of the slider element has a boss formed thereon.

20. A microvalve device comprising:

a body formed of multiple plates of material, an intermediate plate of the body having a cavity defined therein, the cavity having a longitudinal axis, at least a first port and a second port being defined in the body, which ports can communicate with the cavity;

a slider element movable within the cavity along the longitudinal axis of the cavity to selectively substantially block and unblock the first port, thereby selectively controlling fluid communication between the first port and the second port within the microvalve device, the slider element substantially sealing against the body to define a variable-volume region within the cavity, which variable-volume region varies in volume as the slider element moves, the slider element having side portions that cooperate to define an opening in the slider element; and

a trench defined in a plate of the body adjacent to the intermediate plate providing fluid communication between a first point in fluid communication with the variable-volume region and a second point in fluid communication with the second port, a side portion of the slider element and the plate adjacent to the intermediate plate cooperating to enclose fluid in the trench between the first point and the second point.

21. A microvalve device comprising:

a body having a fixed portion and defining at least an axis, a first port, and a second port;

a slider element disposed for movement along the axis within the body, with one axial end of the slider element being exposed to pressure in a variable-volume region defined between the axial end of the slider element and the fixed portion of the body, the slider element being axially movable between a first position blocking flow through the first port and a second position in which flow through the first port to the second port is unblocked;

a first fluid conduit feeding pressure from the second port to the variable-volume region in manner that pressure of the fluid within the first fluid conduit will exert a first force upon the slider element perpendicular to the axis of movement of the slider element; and

a second fluid conduit feeding pressure from the second port to the variable-volume region a manner that pressure of the fluid within the second fluid conduit will exert a second force, opposite in direction and substantially equal in value to the first force, upon the slider element.