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US4454562A Expired / Lapsed US ⏱️ 0.0 years remaining

Keyswitch with telescoping plunger

Assignee: Arris Technology Inc
•
Filing: 1982-09-15
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Granted: 1984-06-12
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Expires: 2002-09-15
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Abstract

Abstract A low profile keyswitch utilizes a telescoping plunger assembly. A linear feel and overtravel are achieved. The telescoping plunger assembly includes an outer plunger shaft and an inner plunger shaft slideably mounted therewithin for telescopic extension therefrom. A retaining member locks one end of the inner plunger shaft within the outer plunger shaft, thereby defining the maximum extension of the inner plunger. A spring biases the inner plunger into its fully extended position.

Inventors

  • 👤 Robert D. Bush
  • 👤 Dean S. Cowles

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 03:33
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/70; H01H13/78; H01H13/80; H01H13/702; H01H13/705; H03; H03K; H03K17/00; H03K17/94; H03K17/965; H03K17/975; H01H2201/00; H01H2201/006; H01H2217/00; H01H2217/02; H01H2221/00; H01H2221/024; H01H2221/026; H01H2221/028; H01H2227/00; H01H2227/036; H01H2233/00; H01H2233/07; H01H2233/086; H01H2233/09; H01H2233/094; H01H2233/096; H01H2239/00; H01H2239/006

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 171 words
An actuator assembly for a low profile keyswitch comprising: a housing; an outer plunger; a channel in said housing through which said outer plunger can slide from a first position to a second position; means for spring loading said outer plunger into said first position; an inner plunger slidably mounted within one end of said outer plunger for telescopic extension therefrom; means for floatably retaining one end of said inner plunger within said outer plunger, thereby defining the maximum extension of said inner plunger from said outer plunger; means for spring loading said inner plunger into its fully extended position; and actuator means at the other end of said inner plunger for actuating a switching element mounted thereunder when said outer plunger is moved from said first to said second position, said actuator having a perimeter smaller than that of the adjacent portions of said housing to enable the actuator to float freely within said housing; whereby said actuator is self-leveling to provide uniform contact with a switching element actuated thereby.
Claim 2
Dependent Claim 171 words
An actuator assembly for a low profile keyswitch comprising: a housing; an outer plunger; a channel in said housing through which said outer plunger can slide from a first position to a second position; means for spring loading said outer plunger into said first position; an inner plunger slidably mounted within one end of said outer plunger for telescopic extension therefrom; means for floatably retaining one end of said inner plunger within said outer plunger, thereby defining the maximum extension of said inner plunger from said outer plunger; means for spring loading said inner plunger into its fully extended position; and actuator means at the other end of said inner plunger for actuating a switching element mounted thereunder when said outer plunger is moved from said first to said second position, said actuator having a perimeter smaller than that of the adjacent portions of said housing to enable the actuator to float freely within said housing; whereby said actuator is self-leveling to provide uniform contact with a switching element actuated thereby.
Claim 3
Dependent Claim 29 words
The assembly of claim 1 wherein said outer plunger comprises a plurality of ribs and grooves which mesh with a plurality of corresponding grooves and ribs in said channel.
Claim 4
Dependent Claim 57 words
The assembly of claim 1 wherein said means for spring loading said inner plunger comprises a substantially flat piece of spring material sandwiched between said one end of said outer plunger and said actuator means and having a plurality of spring fingers cut therefrom with portions of said fingers protruding beyond the flat surface of said piece.
Claim 5
Dependent Claim 37 words
The assembly of claim 1 further comprising actuator means at the other end of said inner plunger for actuating a switching element mounted thereunder when said outer plunger is moved from said first to said second position.
Claim 6
Dependent Claim 66 words
The assembly of claim 1 wherein said actuator means comprises a rigid retaining plate having a foam pad assembly mounted thereto, said foam pad assembly comprising a plate which is snapped into and retained by said rigid retaining plate, a foam pad mounted to the surface of said plate, and a metalized foil secured to the foam pad for actuation of a capacitive type switching element.
Claim 7
Dependent Claim 18 words
The assembly of claim 1 further comprising a keytop mounted to the other end of said outer plunger.
Claim 8
Dependent Claim 52 words
The assembly of claim 1 wherein said means for spring loading said outer plunger into said first position comprises a spiral spring having a first end which bears against a flange extending from the other end of said outer plunger and a second end which bears against a portion of said housing.
Claim 9
Dependent Claim 49 words
The assembly of claim 1 wherein said inner plunger comprises a pair of spaced, free-standing arms which terminate to form a pair of tapered tabs, and said retaining means comprises a shoulder extending partially across said one end of said outer plunger over which said tapered tabs are snapped.
Claim 10
Dependent Claim 126 words
A telescoping plunger assembly for use in a low profile keyswitch comprising: an outer plunger shaft; an inner plunger shaft slidably mounted within one end of said outer plunger shaft for telescopic extension therefrom; means for retaining one end of said inner plunger shaft within said outer plunger shaft; thereby defining the maximum extension of said inner plunger; a switch actuator at the other end of said inner plunger shaft; and a substantially flat piece of spring material sandwiched between said one end of said outer plunger shaft and said switch actuator and having a plurality of spring fingers cut therefrom with portions of said fingers protruding beyond the flat surface of said piece for spring loading said inner plunger shaft into its fully extended position.
Claim 11
Dependent Claim 126 words
A telescoping plunger assembly for use in a low profile keyswitch comprising: an outer plunger shaft; an inner plunger shaft slidably mounted within one end of said outer plunger shaft for telescopic extension therefrom; means for retaining one end of said inner plunger shaft within said outer plunger shaft; thereby defining the maximum extension of said inner plunger; a switch actuator at the other end of said inner plunger shaft; and a substantially flat piece of spring material sandwiched between said one end of said outer plunger shaft and said switch actuator and having a plurality of spring fingers cut therefrom with portions of said fingers protruding beyond the flat surface of said piece for spring loading said inner plunger shaft into its fully extended position.
Claim 12
Dependent Claim 38 words
The assembly of claim 9 wherein said retaining means comprises a plurality of tapered resilient tabs extending from said inner plunger shaft which snap over a shoulder extending partially across said one end of said outer plunger shaft.
Claim 13
Dependent Claim 21 words
The assembly of claim 9 further comprising means at the other end of said outer plunger shaft for accomodating a keytop.

References Cited (Backward Citations)

US3582594A Cited
US3773997A Cited
US3777082A Cited
US3993884A Cited
US3780237A Cited
US3856998A Cited
US3965399A Cited
US4090229A Cited
US4129758A Cited
US4156802A Cited
US4207448A Cited
US4274752A Cited
US4325102A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-06-12 1987-12-12 1988-06-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-06-12 1991-12-12 1992-06-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-06-12 1995-12-12 1996-06-12 $7700.00 Window Closed / Lapsed

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