Miniaturized switch device

• US 8,258,900 B2
• Filed: 02/16/2011
• Issued: 09/04/2012
• Est. Priority Date: 03/04/2005
• Status: Expired due to Fees

• Current Assignee: HT Microanalytical, Inc. (Rosenberger Technology (Kunshan) Co., Ltd.)
• Original Assignee: HT Microanalytical, Inc. (Rosenberger Technology (Kunshan) Co., Ltd.)
• Inventors: Christenson, Todd Richard
• Primary Examiner(s): Rojas, Bernard
• Application Number:
  US13/028,855
• Publication Number:
  US 20110140814A1
• Time in Patent Office: 566 Days
• Field of Search: 335/78, 200/181
• US Class Current: 335/78
• CPC Class Codes: H01H 2001/0078 with parallel movement of the movable contact relative to the substrate
• CPC Class Codes: H01H 2050/007 Relays of the polarised type, e.g. the MEMS relay beam having a preferential magnetisation direction
• CPC Class Codes: H01H 50/005 using micromechanics

Abstract

The present invention provides a switch suitable for efficient microfabrication. The switch elements are disposed in several layers. Various embodiments provide various switching capabilities and operational characteristics. The switches can be protected by suitable packaging, and can be efficiently fabricated in groups or arrays.

Claims

1. A switch, comprising:

(1) a substrate;

(2) a first layer of a first material that is ferromagnetic, the first layer being disposed on the substrate, and the first layer comprising;

(i) a first flexure, wherein the first flexure is substantially selectively flexible in a first direction that is substantially parallel to the substrate;

(ii) a movable member, wherein the first flexure and the movable member are mechanically connected such that the movable member is selectively movable along the first direction between a first position and a second position;

(iii) a first pad; and

(iv) a second pad;

(3) first and second terminals, mounted relative to the movable member such that when the movable member is in the first position, electrical current can flow between the first and second terminals; and

(4) an electromagnet comprising a coil and a core, wherein the first layer does not comprise the core, and wherein the electromagnet is mounted relative to the first layer such that the core is in physical contact with the first layer and the first pad and second pad function as north and south poles of the electromagnet, and further wherein the movable member moves between the first position and second position based on a flow of electric current in the coil.

2. The switch of claim 1, further comprising first and second contacts, where the first contact is in mechanical communication with the movable member and in electrical communication with the first terminal, and wherein the second contact is in electrical communication with the second terminal, and wherein the first and second contacts mount relative to the movable member such that the first and second contacts are in electrical communication when the movable member is in the first position but not when the movable member is in the second position.

3. The switch of claim 2, wherein the first contact moves substantially parallel to the substrate responsive to motion of the movable member.

4. The switch of claim 1, wherein the core is mechanically coupled with the first pad and second pad via a castellated mechanical interface.

5. The switch of claim 1, further comprising a housing that substantially prevents external contaminants from reaching the movable member, and that enables electrical communication with the terminals.

6. The switch of claim 5, wherein the first layer is disposed on a first side of the substrate, and wherein the terminals are externally accessible on a second side of the substrate, and wherein the housing is substantially disposed on the first side of the substrate.

7. The switch of claim 5, wherein the terminals are externally accessible in a first portion of the substrate, and wherein the housing mounts with a second portion of the substrate.

8. The switch of claim 1, wherein the movable member, first pad, second pad, and core collectively define a closed-loop path for magnetic flux.

9. A switch, comprising:

1) a substrate;

2) a first layer of a first material that is ferromagnetic, the first layer being disposed on the substrate, and the first layer comprising;

(i) a movable member that is movable between first and second positions, and where the movable member is constrained to move substantially parallel to the substrate;

(ii) a first fixed member, wherein the first fixed member and a first portion of the movable member collectively define a first gap when the first electromagnet is not energized; and

(iii) a second fixed member, wherein the second fixed member and a second portion of the movable member collectively define a second gap when the first electromagnet is not energized;

3) first and second terminals, mounted relative to the movable member such that when the movable member is in the first position electrical current can flow between the first and second terminals; and

4) a first electromagnet comprising a first core surrounded by first wires, wherein the first layer does not comprise the first core;

wherein the first core is physically and magnetically coupled with each of the first fixed member and second fixed member such that the first fixed member functions as a first pole of the electromagnet and the second fixed member functions as a second pole of the electromagnet, and wherein an electric current in the first wires induces a first magnetic flux through each of the first gap and the second gap, and further wherein the first magnetic flux induces a first force that moves the movable member between the first position and the second position.

10. The switch of claim 9, wherein the first portion and the first fixed member are in physical contact when the electromagnet is energized, and wherein the second portion and the second fixed member are in physical contact when the electromagnet is energized.

11. The switch of claim 9 further comprising:

a third fixed member, wherein the third fixed member and a third portion of the movable member collectively define a third gap when the second electromagnet is not energized, and wherein the first layer comprises the third fixed member;

a fourth fixed member, wherein the fourth fixed member and a fourth portion of the movable member collectively define a fourth gap when the second electromagnet is not energized, and wherein the first layer comprises the fourth fixed member;

a third terminal, mounted relative to the movable member such that when the movable member is in the second position electrical current can flow between the first and third terminals; and

a second electromagnet comprising a second core surrounded by second wires, wherein the first layer does not comprise the second core;

wherein the second core is physically and magnetically coupled with each of the third fixed member and fourth fixed member such that the third fixed member functions as a first pole of the second electromagnet and the fourth fixed member functions as a second pole of the second electromagnet, and wherein a second electric current in the second wires induces a second magnetic flux through each of the third gap and fourth gap, and further wherein the second magnetic flux induces a second force that moves the movable member between the first and second position.

12. The switch of claim 9, wherein the first layer defines a first plane, and wherein first electromagnet is mounted relative to the first layer such that the first core is not in the first plane.

13. The switch of claim 9, wherein the core is mechanically coupled with each of the first fixed member and second fixed member via a castellated mechanical interface.

14. The switch of claim 9, wherein the movable member, first fixed member, second fixed member, and core collectively define a closed-loop path for magnetic flux.

15. A microfabricated switch comprising:

(1) a substrate;

(2) a first layer of a first material that is ferromagnetic, the first layer being disposed on the substrate, and the first layer comprising;

(i) a movable member that is dimensioned and arranged to move along a direction substantially parallel with the substrate;

(ii) a first terminal and second terminal, mounted relative to the movable member such that (i) when the movable member is in a first position a flow of a first electrical current between the first and second terminals is enabled and (ii) when the movable member is in a second position the flow of the first electrical current between the first and second terminals is disabled; and

(iii) a first fixed member and second fixed member, the first fixed member and second fixed member each comprising ferromagnetic material; and

(3) an electromagnet comprising;

(i) a core comprising ferromagnetic material, wherein the core is not included in the first layer; and

(ii) a winding that is dimensioned and arranged to enable the flow of a second electrical current through the winding;

wherein the core, first fixed member, and second fixed member are physically coupled such that the first fixed member comprises a first pole of the electromagnet and the second fixed member comprises a second pole of the electromagnet; and

wherein the position the movable member is based the flow of the second electrical current.

16. The switch of claim 15 wherein the first layer defines a first plane, and wherein the core lies in a second plane that is entirely outside the first plane.

17. The switch of claim 15 wherein the first layer defines a first plane, and wherein the core lies entirely within the first plane.

18. The switch of claim 15 wherein the movable member is in the first position when the second electrical current flows through the winding.

19. The switch of claim 15 wherein the movable member is in the second position when the second electrical current flows through the winding.

20. The switch of claim 15, wherein the movable member, first fixed member, second fixed member, and core collectively define a closed-loop path for magnetic flux.