Electricity: circuit makers and breakers – Solid contact – Membrane type
Patent
1994-06-29
1995-01-31
Recla, Henry J.
Electricity: circuit makers and breakers
Solid contact
Membrane type
200344, 200345, 200512, H01H 110
Patent
active
053860918
ABSTRACT:
A low profile keyswitch having bearing surfaces on both the inside and outside of the plunger of the keycap member is disclosed. The key switch includes a one-piece switch chimney having a cylindrical upright member, a plurality of arcuate ribs positioned coaxially inwardly of the cylindrical member along with a membrane support member. The chimney receives the cylindrical plunger between the cylindrical member and the ribs to provide bearing surfaces on the plunger closest to the keycap member actuation point to minimize friction when the keycap member is depressed offcenter thereby reducing binding of the keyswitch. A plurality of equidistance upstops are disposed on the lower-end of the plunger to reduce wobble of the keycap member in the extended position.
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RT Series Membrane Keyboard w/Zilog MPU(Z8614), Jan., 1992; NMB Technologies, Inc. of Chatsworth, Calif. (8 pages including 1 page of FIG. 4 having a date of May 16, 1988 for an elevation view of a keyswitch for Minebea Co., Ltd.
Fujitsu Microelectronics, Inc., Electronic Components Division, Keyboard Presentation to Compaq Computer Corporation, Apr. 1, 1992 (20 pages total).
FKB7211 Low-Profile Membrane Laptop/Notebook Standard Keyboard; .COPYRGT.1991 by Fujitsu Limited and Fujitsu Microelectronics, Inc. (2 pages total).
FKB7300 Low-Profile Membrane Custom Keyboard; .COPYRGT.1991 by Fujitsu Limited and Fujitsu Microelectronics, Inc., Edition 1.0 (2 pages total).
New Low-Profile Desktop Keyboard FKB4850 Series: Compact Design with Superior Key Operability; .COPYRGT.1991 by Fujitsu Limited and Fujitsu Microelectronics, Inc. (2 pages total).
Fujitsu Keyboards FKB4700 Series; .COPYRGT.1990 Fujitsu Limited of Tokyo, Japan (4 pages total).
SMK Keyboards Catalogue, particularly noting pp. 53-60 for SMK Standard Keyboard and 61-86 for Custom Made Keyboards (113 pages total).
Compaq Computer Corporation
Recla Henry J.
Walczak David J.
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