Push switch with improved actuator assembly

• US 5,152,392 A
• Filed: 05/24/1991
• Issued: 10/06/1992
• Est. Priority Date: 06/11/1990
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Iwasa, Seiichi
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): BARRETT, GLENN
• Application Number:
  US07/705,650
• Time in Patent Office: 501 Days
• Field of Search: 200/512, 200/517, 200/341, 200/329, 200/5 A, 200/306, 200/82 C, 200/83 R, 200/83 B, 200/83 N, 200/83 Z, 200/331
• US Class Current: 200/517
• CPC Class Codes: H01H 13/705 characterised by construction, mounting or arrangement of operating parts, e.g. push-buttons or keys
• CPC Class Codes: H01H 2217/008 Pretravel to avoid inadvertent switching
• CPC Class Codes: H01H 2217/02 After travel
• CPC Class Codes: H01H 2221/02 pneumatic
• CPC Class Codes: H01H 2221/084 made at least partly of elastic foam
• CPC Class Codes: H01H 2227/034 Regulation of operating force

Abstract

A push switch includes a support, a switching-element assembly arranged on the support, and an actuator assembly arranged on the switching-element assembly. The switching-element assembly includes first and second contacts vertically arranged, with the second contact being elastically movable toward the first contact and making contact with the first contact when depressed by the actuator assembly. The basic actuator assembly includes an airtight enclosure of an elastic film having a domed shape and a gas enclosed therein, so that the bottom surface of the airtight enclosure depresses the second contact by a depression force onto the top surface thereof.

Claims

1. A push switch comprising:

a switching-element assembly; and

an actuator assembly arranged on the switching-element assembly,

said switching-element assembly including a first fixed contact and a second movable contact vertically arranged, the second movable contact being movable toward the first fixed contact and making contact with the first fixed contact when depressed by said actuator assembly,

said actuator assembly including a dome-shaped airtight enclosure having a dome-shaped top surface formed of an elastic film and a flat bottom surface formed of an elastic film and a gas enclosed therein, the top surface is secured to the bottom surface thereby forming the dome-shaped airtight enclosure, the bottom surface of the dome-shaped airtight enclosure being arranged with respect to said second movable contact to depress said second movable contact when a depression force is applied to the top surface of the dome-shaped airtight enclosure.

2. A push switch as recited in claim 1, wherein said elastic film of a domed shape comprises a top member having a spherical surface and a bottom flat member.

3. A push switch as recited in claim 2, wherein said elastic film is formed of one of thermoplastic resin and silicone rubber.

4. A push switch as recited in claim 2, wherein said airtight enclosure further comprises a partition member dividing said airtight enclosure into first and second airtight subenclosures, said gas comprising a first gas in said first subenclosure and a second gas in said second subenclosure.

5. A push switch as recited in claim 4, wherein a gas pressure in each of said first and second subenclosures is different.

6. A push switch as recited in claim 4, wherein said first and second airtight subenclosures are formed of one of thermoplastic resin and silicone rubber.

7. A push switch as recited in claim 4, further comprising a support panel, wherein said switching-element assembly and said actuator assembly are arranged on said support panel.

8. A push switch as recited in claim 4, wherein said actuator assembly further comprises a slider assembly disposed thereon, said slider assembly comprising:

a fixed housing having a vertical hole;

a slider vertically movable in said vertical hole; and

a key-top fixed on said slider, the slider having a bottom end contacting the top surface of said airtight enclosure, whereby depression of said key-top is transformed into the depression force on said airtight enclosure.

9. A push switch as recited in claim 4, wherein said actuator assembly further comprises a key top made of transparent material and fixed on the top surface of said actuator assembly, said key top having a printed mark on the bottom surface thereof.

10. A push switch as recited in claim 4, wherein arrangement of said actuator assembly on said switching-element assembly is replaceable.

11. A matrix switch array comprising a plurality of push switches as recited in claim 4 is arranged on a support panel.

12. A push switch as recited in claim 1, wherein said airtight enclosure is embedded in another airtight main enclosure of an elastic film having a domed shape and enclosing another gas, the bottom surface of the first airtight enclosure being exposed and contacting with upper surface of the switching-element assembly, thereby said airtight first enclosure and another main enclosure forming said actuator assembly.

13. A push switch as recited in claim 12, wherein each gas pressure in said two enclosures is different from each other.

14. A push switch as recited in claim 12, wherein the material of said two airtight enclosures is either thermoplastic resin or silicone rubber.

15. A push switch as recited in claim 12, wherein said switching-element assembly and actuator assembly are arranged on a support panel.

16. A push switch as recited in claim 12, wherein said actuator assembly further comprises a key top made of transparent material and fixed on the top of the actuator assembly, said key top having a printed mark such as character and symbol on the bottom surface thereof.

17. A push switch as recited in claim 12, wherein arrangement of said actuator assembly on said switching-element assembly is replaceable.

18. A matrix switch array comprising a plurality of push switches as recited in claim 12 is arranged on a support panel.

19. A push switch as recited in claim 1, wherein said actuator assembly further comprises a main body of an elastic foaming material having a domed shape, wherein said airtight enclosure is embedded in said main body of an elastic foaming material having a domed shape, the bottom surface of the airtight enclosure being exposed and contacting an upper surface of said switching-element assembly, so that said airtight enclosure and said main body form said actuator assembly.

20. A push switch as recited in claim 19, wherein said elastic foaming material of the main body is polyurethane sponge.

21. A push switch as recited in claim 19, further comprising a support panel, wherein said switching-element assembly and said actuator assembly are arranged on said support panel.

22. A push switch as recited in claim 12, wherein said actuator assembly further comprises a slider assembly disposed thereon, the slider assembly further comprising a fixed housing having a vertical hole, a slider vertically movable in said hole, and a key-top fixed on the slider, the bottom end of the slider contacting with the top surface of the domed actuator, whereby depression of the key-top is transformed into the depression force onto said domed actuator assembly.

23. A push switch as recited in claim 19, wherein said actuator assembly further comprises a slider assembly disposed thereon, said slider assembly comprising:

a fixed housing having a vertical hole;

a slider vertically movable in said vertical hole; and

a key-top fixed on said slider, the slider having a bottom end contacting the top surface of said airtight enclosure, whereby depression of said key-top is transformed into the depression force on said airtight enclosure.

24. A push switch as recited in claim 19, wherein said actuator assembly further comprises a key top made of transparent material and fixed on the top surface of said actuator assembly, said key top having a printed mark on the bottom surface thereof.

25. A push switch as recited in claim 19, wherein arrangement of said actuator assembly on said switching-element assembly is replaceable.

26. A matrix switch array comprising a plurality of push switches as recited in claim 19 is arranged on a support panel.

27. A push switch as recited in claim 1, further comprising a support panel, wherein said switching-element assembly and said actuator assembly are arranged on said support panel.

28. A push switch as recited in claim 1, wherein said actuator assembly further comprises a slider assembly disposed thereon, said slider assembly comprising:

a fixed housing having a vertical hole;

a slider vertically movable in said vertical hole; and

a key-top fixed on said slider, the slider having a bottom end contacting the top surface of said airtight enclosure, whereby depression of said key-top is transformed into the depression force on said airtight enclosure.

29. A push switch as recited in claim 1, wherein said actuator assembly further comprises a key top made of transparent material and fixed on the top surface of said actuator assembly, said key top having a printed mark on the bottom surface thereof.

30. A push switch as recited in claim 1, wherein arrangement of said actuator assembly on said switching-element assembly is replaceable.

31. A matrix switch array comprising a plurality of push switches as recited in claim 1, arranged on a support panel.