MULTI-STAGE SPRING SYSTEM

• US 20090261517A1
• Filed: 04/21/2008
• Published: 10/22/2009
• Est. Priority Date: 04/21/2008
• Status: Active Grant

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: YAO, JUN JASON
• Granted Patent: US 8,528,885 B2
• Time in Patent Office: Days
• US Class Current: 267/160
• CPC Class Codes: F16F 3/02 with springs made of steel or of other material having low internal friction
• 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 1/18 with subsequent sliding
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 59/0009 making use of micromechanics

Abstract

Embodiments of a multi-stage spring system are provided herein. In some embodiments, a multi-stage spring system includes a spring assembly having at least one resilient element, wherein the spring assembly has a first spring constant when deflected up to a first distance, a greater, second spring constant when deflected beyond the first distance and up to a second distance, and a greater, third spring constant when deflected beyond the second distance and up to a third distance, and wherein the spring assembly stores mechanical energy when deflected towards a contact surface that biases the spring assembly away from the contact surface when released.

Claims

1. A multiple-stage spring system, comprising:

a spring assembly having at least one resilient element, wherein the spring assembly has a first spring constant when deflected up to a first distance, a greater, second spring constant when deflected beyond the first distance and up to a second distance, and a greater, third spring constant when deflected beyond the second distance and up to a third distance, and wherein the spring assembly stores mechanical energy when deflected towards a contact surface that biases the spring assembly away from the contact surface when released.

2. The system of claim 1, further comprising:

a second resilient element disposed in a spaced apart relation to the first resilient element and configured to contact the first resilient element upon deflection of the first resilient element towards the contact surface.

3. The system of claim 1, further comprising:

a plurality of resilient elements configured to be engaged upon varying quantities of deflection of the spring assembly towards the contact surface.

4. The system of claim 1, further comprising:

a second resilient element having a tip coupled thereto and configured to provide a wiping motion against the contact surface upon continued deflection of the second resilient element after initial contact with the contact surface.

5. The system of claim 1, further comprising:

a stop configured to limit the deflection of the spring assembly.

6. The system of claim 1, further comprising an actuator coupled to the spring assembly.

7. The system of claim 6, wherein the actuator is an electrostatic actuator.

8. The system of claim 6, wherein the actuator comprises at least one of a comb drive or a gap closing actuator.

9. The system of claim 6, wherein the actuator comprises an angled gap closing actuator, a partitioned MEMS actuator, or a multi-stage actuator.

10. The system of claim 6, wherein the spring assembly stores mechanical energy that corresponds to the force applied by the actuator.

11. The system of claim 1, wherein the resilient element comprises silicon.

12. The system of claim 1, further comprising:

a tip coupled to the spring assembly and configured to wipe a contact surface upon continued deflection of the spring assembly after initial contact with the contact surface.

13. The system of claim 12, wherein the tip comprises a metal.

14. The system of claim 12, wherein the tip comprises at least one of copper, aluminum, gold, rhodium, or palladium.

15. The system of claim 12, wherein the tip is configured to contact two contact surfaces disposed in a spaced apart relation.

16. The system of claim 15 further comprising:

a mechanism for facilitating rotation of the tip upon contact with the two contact surfaces.

17. The system of claim 16, wherein the mechanism comprises at least one of a hinge, a flexure, or a spring.

18. The system of claim 15, wherein the two contact surfaces and the tip are electrically conductive and at least partially define an electrical switch.

19-36. -36. (canceled)