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US4119821A Expired / Lapsed US ⏱️ 0.0 years remaining

Normally closed switch

Assignee: Stackpole Components Co
•
Filing: 1977-09-26
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Granted: 1978-10-10
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Expires: 1997-09-26
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Abstract

Abstract A switch case has a top provided with a central opening in which slides the stem of a plunger that has a foot inside the case. A bridging contact spring has a central portion engaging the foot and has free end portions extending away from opposite sides of the foot to form movable contacts normally engaging stationary electric contacts in the case beneath the movable contacts. Between each stationary contact and the central portion of the spring there is a fulcrum member beneath a movable contact so that when the central portion of the spring is moved downwardly by depressing the plunger, the movable contacts will rock on the fulcrum members and lift away from the stationary contacts.

Inventors

  • 👤 Arthur Wayne Overton

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 17:32
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/02; H01H13/12; H01H1/00; H01H1/12; H01H1/14; H01H1/24; H01H1/242

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 204 words
A normally closed switch comprising a case having a top with an opening therethrough, a plunger having a foot in the case and a stem extending upwardly through said opening and above the case, a bridging contact member in the case at the lower end of the plunger, said contact member being formed from a spring having a central portion engaging said foot and having free end portions extending away from opposite sides of the foot to form movable contacts, a pair of stationary electric contacts mounted in the case beneath said movable contacts and normally engaged thereby, terminals connected with the stationary contacts and extending out of the case, and a fulcrum member in the case between each stationary contact and said central portion of the spring, said fulcrum members being disposed beneath said movable contacts and normally out of contact with them, the tops of the fulcrum members being lower than the tops of said stationary contacts, and the fulcrum members being of such height that when said central portion of the spring is moved downwardly by depressing the plunger said movable contacts will engage and rock on the fulcrum members and lift away from the stationary contacts to open the switch.
Claim 2
Dependent Claim 204 words
A normally closed switch comprising a case having a top with an opening therethrough, a plunger having a foot in the case and a stem extending upwardly through said opening and above the case, a bridging contact member in the case at the lower end of the plunger, said contact member being formed from a spring having a central portion engaging said foot and having free end portions extending away from opposite sides of the foot to form movable contacts, a pair of stationary electric contacts mounted in the case beneath said movable contacts and normally engaged thereby, terminals connected with the stationary contacts and extending out of the case, and a fulcrum member in the case between each stationary contact and said central portion of the spring, said fulcrum members being disposed beneath said movable contacts and normally out of contact with them, the tops of the fulcrum members being lower than the tops of said stationary contacts, and the fulcrum members being of such height that when said central portion of the spring is moved downwardly by depressing the plunger said movable contacts will engage and rock on the fulcrum members and lift away from the stationary contacts to open the switch.

References Cited (Backward Citations)

US3767878A Cited
US4046982A Cited
US3924089A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-09 1982-04-10 1982-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-09 1986-04-10 1986-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-09 1990-04-10 1990-10-10 $7700.00 Window Closed / Lapsed

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