ELECTRICAL SWITCH ASSEMBLY

• US 20090229961A1
• Filed: 03/10/2009
• Published: 09/17/2009
• Est. Priority Date: 03/13/2008
• Status: Active Grant

• Current Assignee: Omron Automotive Electronics Company Limited (Nidec Corporation)
• Original Assignee: Omron Dualtec Automotive Electronics, Inc. (Omron Corporation)
• Inventors: Larsen, Christopher, Beyginian, Albert, Nuica, Theodor
• Granted Patent: US 8,138,432 B2
• Time in Patent Office: Days
• US Class Current: 200/343
• CPC Class Codes: H01H 2021/225 with push-pull operation, e.g. which can be pivoted in both directions by pushing or pulling on the same extremity of the operating member
• CPC Class Codes: H01H 21/24 biased to return to normal position upon removal of operating force
• CPC Class Codes: H01H 2221/064 Limitation of actuating pressure

Abstract

A switch assembly operating an electrical circuit using an elastomeric pad is provided. The elastomeric pad comprises one or more collapsible domes that are positioned such that a plunger element supported by the switch assembly collapses the domes when an actuation button is tilted. The plunger element may have a limiting mechanism to limit downward movement of the plunger element such that the collapsible domes are not overloaded. The body and plunger may also be formed with complementary profiled portions that restrict any one or more of fore/aft, side-to-side and up/down movements of the plunger with respect to the body to prevent abnormal loading on the collapsible domes to increase the lifecycle of the elastomeric portion. The elastomeric portion may also be adapted to provide both single and dual double detent feedback by using passive collapsible domes that provide tactile feedback without operating on the electrical circuit.

Claims

1. A switch assembly comprising:

a body;

an actuation button pivotally supported by said body;

an electrical circuit portion underlying said actuation button;

an elastomeric portion overlying said electrical circuit portion, said elastomeric portion having at least one collapsible dome formed therein for providing a connection on said electrical circuit portion when said dome is in a collapsed position;

a plunger element supported by said body between said actuation button and said elastomeric portion, said plunger element comprising a first upwardly directed portion bearing against said actuation button such that movement of said actuation button causes said plunger element to move towards said elastomeric portion, and a second downwardly directed portion aligned with said collapsible dome such that said movement of said actuation button beyond a predetermined threshold causes said plunger element to collapse said elastomeric dome; and

a limiting mechanism between said plunger element and said elastomeric portion to restrict said movement beyond a lower limit to protect overloading of said collapsible dome.

2. The switch assembly according to claim 1 wherein said limiting mechanism comprises a downwardly extending post protruding from said plunger element.

3. The switch assembly according to claim 2 wherein said post is aligned with said first upwardly directed portion along a line of action of said actuation button.

4. The switch assembly according to claim 1 wherein said limiting mechanism comprises one or more blades extending between said plunger element and said elastomeric portion.

5. A switch assembly comprising:

a body;

an actuation button pivotally supported by said body;

an electrical circuit portion underlying said actuation button;

an elastomeric portion overlying said electrical circuit portion, said elastomeric portion having at least one collapsible dome formed therein for providing a connection on said electrical circuit portion when said dome is in a collapsed position; and

a plunger element supported by said body between said actuation button and said elastomeric portion, said plunger element comprising a first upwardly directed portion bearing against said actuation button such that movement of said actuation button causes said plunger element to move towards said elastomeric portion, a second downwardly directed portion aligned with said collapsible dome such that said movement of said actuation button beyond a predetermined threshold causes said plunger element to collapse said elastomeric dome, and at least one profiled portion for interacting with a complementary profiled portion on said body to restrict movement of said plunger element in the plane defined by said electrical circuit portion.

6. The switch assembly according to claim 5 wherein said profiled portion is positioned to restrict fore and aft movements of said plunger element with respect to said body.

7. The switch assembly according to claim 5 wherein said profiled portion is positioned to restrict side-to-side movements of said plunger element with respect to said body.

8. The switch assembly according to claim 5 wherein said body comprises a vertical limiting mechanism for locating said plunger element in said body during assembly of said switch assembly.

9. A switch assembly comprising:

a body;

an actuation button pivotally supported by said body;

an electrical circuit portion underlying said actuation button;

an elastomeric portion overlying said electrical circuit portion, said elastomeric portion having at least one active collapsible dome formed therein for providing a connection on said electrical circuit portion when said dome is in a collapsed position and comprising at least one passive collapsible dome formed therein for providing tactile feedback during operation of said actuation button without operating on said electrical circuit portion; and

a plunger element supported by said body between said actuation button and said elastomeric portion, said plunger element comprising a first upwardly directed portion bearing against said actuation button such that movement of said actuation button causes said plunger element to move towards said elastomeric portion, a second downwardly directed portion aligned with said active collapsible dome such that said movement of said actuation button beyond a predetermined threshold causes said plunger element to collapse said active elastomeric dome, and a third downwardly directed portion aligned with said passive collapsible dome such that said movement also causes said plunger element to collapse said elastomeric dome.

10. The switch assembly according to claim 9 wherein said passive collapsible dome collapses under a force which is greater than that required to collapse said active collapsible dome.

11. A plunger element for a switch assembly having a body, an actuation button supported by said body above an elastomeric portion with at least one collapsible dome, said plunger element to be supported by said body between said actuation button and said elastomeric portion, said plunger element comprising:

a first upwardly directed portion bearing against said actuation button such that movement of said actuation button causes said plunger element to move towards said elastomeric portion, a second downwardly directed portion aligned with said collapsible dome such that said movement of said actuation button beyond a predetermined threshold causes said plunger element to collapse said elastomeric dome, and a limiting mechanism to restrict movement of said plunger element with respect to said elastomeric portion.

12. The plunger element according to claim 11 wherein said limiting mechanism is located between said plunger element and said elastomeric portion to restrict said movement beyond a lower limit to protect overloading of said collapsible dome.

13. The plunger element according to claim 11 wherein said limiting mechanism comprises a downwardly extending post protruding from said plunger element.

14. The plunger element according to claim 13 wherein said post is aligned with said first upwardly directed portion along a line of action of said actuation button.

15. The plunger element according to claim 11 wherein said limiting mechanism comprises one or more blades extending between said plunger element and said elastomeric portion.

16. The plunger element according to claim 11 wherein said limiting mechanism comprises at least one profiled portion for interacting with a complementary profiled portion on said body to restrict movement of said plunger element in the plane defined by said electrical circuit portion.

17. The plunger element according to claim 16 wherein said profiled portion is positioned to restrict fore and aft movements of said plunger element with respect to said body.

18. The plunger element according to claim 16 wherein said profiled portion is positioned to restrict side-to-side movements of said plunger element with respect to said body.

19. The plunger element according to claim 16 wherein said body comprises a vertical limiting mechanism for locating said plunger element in said body during assembly of said switch assembly.

20. An elastomeric portion for a switch assembly having a body, an actuation button supported by said body, an electrical circuit portion, and a plunger element to be supported by said body between said actuation button and said elastomeric portion, said elastomeric portion to be interposed between said plunger element and said electrical circuit portion, said elastomeric portion comprising at least one active collapsible dome formed therein for providing a connection on said electrical circuit portion when said dome is in a collapsed position and comprising at least one passive collapsible dome formed therein for providing tactile feedback during operation of said actuation button without operating on said electrical circuit portion.