Microelectromechanical systems (MEMS) -type devices having latch release and output mechanisms

• US 6,321,654 B1
• Filed: 04/24/2000
• Issued: 11/27/2001
• Est. Priority Date: 02/22/2000
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Robinson, Charles H.
• Primary Examiner(s): Jordan, Charles T.
• Assistant Examiner(s): LOFDAHL, JORDAN M
• Application Number:
  US09/560,527
• Time in Patent Office: 582 Days
• Field of Search: 102/222, 102/235, 102/247, 102/251, 102/202
• US Class Current: 102/251
• CPC Class Codes: F42C 15/24 wherein the safety or arming action is effected by inertia means F42C15/196, F42C15/20 take precedence
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 2001/0047 operable only by mechanical latching
• CPC Class Codes: H01H 35/14 Switches operated by change of acceleration, e.g. by shock or vibration, inertia switch wherein the liquid constitutes a contact of the switch H01H29/002

Abstract

A first embodiment of the invention comprises a miniature release and latch anchor assembly that can be fabricated in combination with other moving and fixed elements on a single substrate (3). Such a release and latch anchor assembly has many applications in MEMS-type devices, particularly devices whose moving elements react in response to predetermined inertial loading inputs externally imposed thereupon. This embodiment provides ways of imposing or enforcing sequential operations of moving parts in a MEMS-type device, a necessary operational requirement for safety and proper arming of projected munitions. A second embodiment of the invention is a variation of the first embodiment wherein a reinsertable-re-releasable latch anchor assembly mechanism has insertable anchor feet members (5) in cooperation with the linchpin member (7) whereby re-latching of the anchor assembly can occur. A third embodiment of the invention comprises various designs of mechanical output pin (25) in various assemblies for relay functioning. These output pin assemblies are part of an integrated or coupled MEMS-type device that mechanically closes or opens an output actuated device such as a valve, electrical contacts or optical transmitting device.

Claims

1. A microelectromechanical systems (MEMS)-type latch and release device fabricated on a common die, the device comprising:

a base;

a slider member slidably mounted on the base

a track that guides movements of the slider member;

an anchor assembly having two flexible anchor legs attached to the slider member, movable anchor feet that are attached to distal ends of each anchor leg, the anchor legs cooperatively and slidably engage corresponding constriction members that attach to the base through the anchor feet, and a movable linchpin member, wherein the linchpin member slidably moves between the anchor feet; and

means for removing the linchpin member and allowing the anchor feet to move together causing subsequent release of the slider member and movement within the track.

2. The device as recited in claim 1, wherein the anchor assembly further includes a spring member that attaches between the base and the linchpin so that when the anchor feet are pressed into the constriction members, the linchpin is biased by the spring causing reinsertion of the linchpin between the anchor legs and effectuating relatching of the device, thereby providing a relatching device.

3. The device as recited in claim 1, wherein the anchor feet have a catch member that prevents reinsertion of the feet through the constriction members, cooperative interfacing linchpin and the anchor feet have a 5-degree taper angle, thereby providing a one-way latch-release device.

4. The device as recited in 1, wherein the slider member is juxtaposed to a zig-zag track on each side of the slider member, in which the slider member slides, the slider member has teeth members on each side of the slider member that cooperatively slidably engage the zig-zag track members, thereby enabling time-delay for travel of the slider member when subjected to inertial loading.

5. The device as recited in 2, wherein the slider member is juxtaposed to a zig-zag track on each side of the slider member, in which the slider member slides, the slider member has teeth members on each side of the slider member that cooperatively slidably engage the zig-zag track members, thereby enabling time-delay for travel of the slider member when subjected to inertial loading.

6. A microelectromechanical systems (MEMS)-type output relaying device, the device comprising:

a base forming a single die type structure;

a slider member slidably mounted on the base;

a first track that restricts movement of the slider member;

a slidable output pin that cooperatively engages the slider member, the pin is restricted within a second track such that when the slider member engages the output pin during inertial loading of the relaying device, a distal end of the output pin extends beyond the second track and maintains attachment thereto; and

an output effector means having at least two operational states.

7. The relaying device as recited in claim 6, wherein the output pin has at least one catch member attached to at least one side of the output pin, the at least one catch member cooperatively engages at least one recess with a finger catch member within the second track, the second track has a break away section in the die for providing stable positioning of the output pin prior to actuation of the device, whereby the output pin remains latched in an extended position when deployed.

8. The relaying device as recited in claim 6, wherein the output effector means comprises a displaceable mechanical relay member that has at least two states of operation.

9. The relaying device as recited in claim 6, wherein the output effector means comprises an optical switch.

10. The relaying device as recited in claim 8, wherein the mechanical relay member blocks motion of a juxtaposed mechanically actuated device.

11. The relaying device as recited in claim 8, wherein the mechanical relay member enables motion of a juxtaposed mechanically actuated device.

12. The relaying device as recited in claim 11, wherein the mechanically actuated device comprises a diaphragm that is puncturable.

13. The relaying device as recited in claim 11, wherein the mechanically actuated device comprises a fluid valve.

14. The relaying device as recited in claim 10, wherein the mechanically actuated device comprises an electromagnetic (EM) source and an optical fiber wherein the output pin interrupts transmissions of EM radiation when actuated.

15. The relaying device as recited in claim 11, wherein the mechanically actuated device comprises an optical fiber and sensor wherein the output pin redirects the optical fiber towards the sensor when actuated.

16. The relaying device as recited in claim 10, wherein the mechanically actuated device comprises an electromagnetic (EM) source and at least two EM sensors, wherein the output pin interrupts transmission of EM radiation to one of the sensors and reflects radiation from the source to one of the other sensors when actuated.

17. The relaying device as recited in claim 8, wherein the mechanically actuated device comprises an electrical switch.

18. The relaying device as recited in claim 17, wherein the electrical switch is a normally closed type switch.

19. The relaying device as recited in claim 17, wherein the electrical switch is a normally open type switch.

20. The relaying device as recited in claim 8, wherein the mechanically actuated device includes a visual indicator.

21. The relaying device as recited in claim 8, wherein the mechanically actuated device comprises a latch arm and auxiliary slider member such that when actuated, the latch arm releases the auxiliary slider member so as to move within an auxiliary track.

22. The relaying device as recited in claim 6, wherein the slider member attaches to the output pin and the first track is substantially parallel and aligned with the second track.

23. The relaying device as recited in claim 21, wherein a structural centerline of the slider member and the output pin are collinear and form an output lance member.

24. The device as recited in claim 6, wherein a protruding head member attached to the slider member has a catch engagement member that cooperatively engages and latches with contact members attached to a section of the first track during actuation of the device.

25. The device as recited in claim 24, wherein a protruding head member attached to the slider member has a catch engagement member that cooperatively engages and latches with contact members attached to a section of the first track during actuation of the device.

26. The device as recited in claim 24, wherein the second track has a break away wall that bridges to the die and an initial stabilized and sealed configuration can be maintained until the output pin breaks away from the die and deployed.

27. A safety and arming (S&

A) device for a projected munitions formed on a common substrate, comprising;

setback slider means responsive to acceleration of the munitions for moving from an initial position to a final position on the base within a first track;

set forward slider means responsive to movement of the setback slider means for moving, from an initial position toward a final position on the base within a second track;

an anchor latch and release assembly that includes two flexible anchor legs attached to the set forward slider member, movable anchor feet that are attached to distal ends of each anchor leg, the anchor legs cooperatively and slidably engage corresponding constriction members that attach to the base through the anchor feet, and a movable linchpin member, wherein the linchpin member slidably moves between the anchor feet;

an interlocking arm cantilevered and movable at the final position of the setback slider, the interlocking arm attaches to the linchpin member thereby allowing the anchor feet to move together and release the set forward slider member from the constriction members so as to be released and movable within the second track; and

a slidable output pin that cooperatively engages the set forward slider means, the output pin is restricted within a third track such that when the set forward slider means engages the output pin during inertial loading of the relaying device, a distal end of the output pin extends beyond the third track and remains attached thereto.

28. The device recited in claim 27, wherein the output pin interfaces with an output effector means having at least two operational states, thereby effectuating relaying action.

29. The device as recited in 27, wherein at least one of the slider means is juxtaposed to a zig-zag track on each side of the at least one slider means, in which each of the at least one slider means slides, the at least one slider means has teeth members on each side of the respective slider means that cooperatively slidably engage the zig-zag track members, thereby enabling time-delay for travel of the at least one slider means when subjected to inertial loading.