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US5280147A Expired / Lapsed US ⏱️ 0.0 years remaining

Keyswitch assembly with a key support limiting transverse, longitudinal and rotational movement of the key

Assignee: Brother Industries Ltd
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Filing: 1992-10-28
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Granted: 1994-01-18
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Expires: 2012-10-28
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Abstract

Abstract The present invention provides a keyswitch assembly enabling a keyboard employing the same to be formed in a small thickness without sacrificing the stroke of the key to the reduction of thickness of the keyboard, facilitating keystroke operation and securing reliable keystroke. The keyswitch assembly has a key supported on a base plate by a support mechanism formed by pivotally connecting first and second support levers each provided with pivots at their opposite ends in a scissors-like form by a pivotal joint. The support levers are connected to the key and the base plate by fitting the pivots thereof in round holes and horizontally elongate grooves formed in the key and in round holes and horizontally elongate grooves formed in the base plate. When the key is depressed, the first and second support levers turn on the pivots fitted pivotally in the round holes and the pivotal joint compresses a rubber spring disposed under the support mechanism for switching.

Inventors

  • 👤 Isao Mochizuki
  • 👤 Takeyuki Takagi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 16:11
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/02; H01H13/12; H01H13/20; H01H13/14; H01H3/00; H01H3/02; H01H3/12; H01H3/122; H01H3/125

Claims Analysis

Total Claims: 67
Claim 1
Independent Claim 118 words
A keyswitch assembly comprising: a key; a base plate disposed beneath said key; key support supporting said key for perpendicular movement with respect to said base plate, and comprising first and second levers pivotally joined and forming a scissors-type mechanism with a pivot axis, said first lever having a first end pivotally connected to said key and a second end slidably connected to said base plate, said second lever having a first end slidably connected to said key and a second end pivotally connected to said base plate; and a switching member disposed between said base plate and said key support, wherein upon depression of said key, said key support bears on said switching member to actuate switching.
Claim 2
Dependent Claim 118 words
A keyswitch assembly comprising: a key; a base plate disposed beneath said key; key support supporting said key for perpendicular movement with respect to said base plate, and comprising first and second levers pivotally joined and forming a scissors-type mechanism with a pivot axis, said first lever having a first end pivotally connected to said key and a second end slidably connected to said base plate, said second lever having a first end slidably connected to said key and a second end pivotally connected to said base plate; and a switching member disposed between said base plate and said key support, wherein upon depression of said key, said key support bears on said switching member to actuate switching.
Claim 3
Dependent Claim 15 words
The keyswitch assembly according to claim 1 wherein said switching member is a rubber spring.
Claim 4
Dependent Claim 65 words
The keyswitch assembly according to claim 1 wherein said switching member is an inverted truncated cone having a base flange, a flexible conical side wall and a top wall with an upper and a lower surface, said side wall buckling when said key support means bears on said upper surface and wherein an electrical contact is disposed on said lower surface within said switching member.
Claim 5
Dependent Claim 25 words
The keyswitch assembly according to claim 1 wherein said first and second levers delineate a downwardly concave space in which said switching member is disposed.
Claim 6
Dependent Claim 52 words
The keyswitch assembly according to claim 1 wherein each of said levers has an upper arm, a lower arm and a body, said upper arm and said lower arm extending perpendicularly from said body, and a pair of opposed pivots extending from each end of said upper arm and said lower arm.
Claim 7
Dependent Claim 25 words
The keyswitch assembly according claim 1, wherein said key support includes a bearing surface located at said pivot axis for bearing on said switching member.
Claim 8
Dependent Claim 13 words
The keyswitch assembly according to claim 6, wherein said bearing surface is semi-circular.
Claim 9
Dependent Claim 34 words
The keyswitch assembly according to claim 6, wherein said bearing surface includes two surfaces disposed at an obtuse angle on each said first and second levers, said angle being aligned with said pivot axis.
Claim 10
Dependent Claim 20 words
The keyswitch assembly according to claim 6, wherein each lever has a polygonal body which acts as the bearing surface.
Claim 11
Dependent Claim 17 words
The keyswitch assembly according to claim 6, wherein said bearing surface has at least two obtuse angles.
Claim 12
Dependent Claim 35 words
The keyswitch assembly according to claim 1, wherein said first lever has a shaft extending laterally therefrom and said second lever has a hole extending laterally therethrough, said shaft being rotatably secured in said hole.
Claim 13
Dependent Claim 33 words
The keyswitch assembly according to claim 1, wherein said second end of said first lever and said first end of second lever slide longitudinally with respect to said key and said base plate.
Claim 14
Dependent Claim 56 words
The keyswitch assembly according to claim 12, wherein said first end of said first lever, said second end of said first lever and said second end of said second lever are equally spaced from said pivot axis, and said first end of said first lever and said second end of said second lever are longitudinally immovable.
Claim 15
Dependent Claim 116 words
The keyswitch assembly according to claim 13, wherein said first end of said first lever has a pair of opposed ends aligned along a first line connecting said pair of ends, said second end of said first lever has a pair of opposed ends aligned along a second line connecting said pair of ends, and said second end of said second lever has a pair of opposed ends aligned along a third line connecting said pair of ends, wherein a shortest distance between said first line and said pivot axis, a shortest distance between said second line and said pivot axis and a shortest distance between said third line and said pivot axis are the same.
Claim 16
Dependent Claim 47 words
The keyswitch assembly according to claim 13, wherein said first end of said second lever is the same distance from said pivot axis as said second end of said first lever, and said lower surface of said key remaining level with respect to movement of said key.
Claim 17
Dependent Claim 58 words
The keyswitch assembly according to claim 15, wherein said first end of said second lever has a pair of opposed ends aligned along a fourth line connecting said pair of ends, wherein a shortest distance between said fourth line and said pivot axis is the same as the shortest distance between said second line and said pivot axis.
Claim 18
Dependent Claim 40 words
The keyswitch assembly according to claim 13, wherein said first end of said second lever is spaced an unequal distance from said pivot axis compared to, the distance between said second end of said first lever and said pivot axis.
Claim 19
Dependent Claim 23 words
The keyswitch assembly according to claim 13, wherein said first and second levers have lateral stop surfaces and said key is laterally immovable.
Claim 20
Dependent Claim 50 words
The keyswitch assembly according to claim 1, comprising a normal axis perpendicular to said base plate extending from said key to said base plate, wherein said first end of said first lever and said second end of said second lever are aligned along a plane parallel to said normal axis.
Claim 21
Dependent Claim 50 words
The keyswitch assembly according to claim 1, comprising a normal axis perpendicular to said base plate extending from said key to said base plate, wherein said second end of said first lever and said first end of said second lever are aligned along a plane parallel to said normal axis.
Claim 22
Dependent Claim 73 words
A keyswitch assembly comprising: a key; a base plate disposed beneath the key; key support supporting said key for perpendicular movement with respect to said base plate, said key support pivotally coupled to said key and said base plate. a switch having an electrical contact for making electrical connection upon movement of said kay, positioned beneath said key support, wherein said key support contacts and compresses said switch upon movement of said key.
Claim 23
Dependent Claim 73 words
A keyswitch assembly comprising: a key; a base plate disposed beneath the key; key support supporting said key for perpendicular movement with respect to said base plate, said key support pivotally coupled to said key and said base plate. a switch having an electrical contact for making electrical connection upon movement of said kay, positioned beneath said key support, wherein said key support contacts and compresses said switch upon movement of said key.
Claim 24
Dependent Claim 15 words
The keyswitch assembly according to claim 21, wherein said switch is a resilient inverted cup.
Claim 25
Dependent Claim 26 words
The keyswitch assembly according to claim 21, wherein said key support comprises a pair of levers pivotally joined in a scissors arrangement having a pivot axis.
Claim 26
Dependent Claim 29 words
The keyswitch assembly according to claim 23, wherein a lower portion of said levers surrounds said switch, and said key support bears on said switch at said pivot axis.
Claim 27
Dependent Claim 20 words
The keyswitch assembly according to claim 21, wherein said key support means has a semi-circular surface which confronts said switch.
Claim 28
Dependent Claim 26 words
The keyswitch assembly according to claim 21, wherein said key support means has an angular surface having at least one obtuse angle which confronts said switch.
Claim 29
Dependent Claim 39 words
The keyswitch assembly according to claim 21, further comprising a printed circuit board positioned beneath said base plate and wherein said base plate has an opening and said switch is positioned within said opening on said print circuit board.
Claim 30
Dependent Claim 36 words
The keyswitch assembly according to claim 21, wherein a pair of electrical contacts are disposed beneath said switch and said switch has an electrical contact movable to said pair of contacts upon depression of said key.
Claim 31
Dependent Claim 16 words
The keyswitch assembly according to claim 21, wherein said key is laterally, longitudinally and rotatably immovable.
Claim 32
Dependent Claim 166 words
A keyswitch assembly comprising: a key adapted to be depressed and having at least two first connecting parts; a switch for switching action actuated upon depression of said key; a base plate disposed beneath said key for supporting said switch and having at least two second connecting parts; a scissors-type linkage supporting said key and having first, second, third and fourth ends and a pivot axis, said first end pivotally fixed to said first connecting parts, said second end movably connected to said first connecting parts, said third end pivotally fixed to said second connecting parts and said fourth end movably connected to said second connecting parts, said key adapted to be depressed perpendicularly with respect to said base plate and said linkage actuating said switch upon depression of said key, wherein a distance between said first end and said pivot axis, a distance between said third end and said pivot axis and a distance between said fourth end and said pivot axis are the same.
Claim 33
Dependent Claim 166 words
A keyswitch assembly comprising: a key adapted to be depressed and having at least two first connecting parts; a switch for switching action actuated upon depression of said key; a base plate disposed beneath said key for supporting said switch and having at least two second connecting parts; a scissors-type linkage supporting said key and having first, second, third and fourth ends and a pivot axis, said first end pivotally fixed to said first connecting parts, said second end movably connected to said first connecting parts, said third end pivotally fixed to said second connecting parts and said fourth end movably connected to said second connecting parts, said key adapted to be depressed perpendicularly with respect to said base plate and said linkage actuating said switch upon depression of said key, wherein a distance between said first end and said pivot axis, a distance between said third end and said pivot axis and a distance between said fourth end and said pivot axis are the same.
Claim 34
Dependent Claim 37 words
The keyswitch assembly according to claim 30, comprising a normal axis extending from said key to said base plate wherein said first end and said third end are aligned along a plane parallel to said normal axis.
Claim 35
Dependent Claim 24 words
The keyswitch assembly according to claim 30, wherein said first end, a point on said pivot axis and said fourth end are linearly aligned.
Claim 36
Dependent Claim 31 words
The keyswitch assembly according to claim 30, wherein said second end is spaced from said pivot axis the same distance as the distance between said first end and said pivot axis.
Claim 37
Dependent Claim 37 words
The keyswitch assembly according to claim 30, comprising a normal axis extending from said key to said base plate, wherein said second end and said fourth end are aligned along a plane parallel to said normal axis.
Claim 38
Dependent Claim 32 words
The keyswitch assembly according to claim 30, wherein said second end is spaced from said pivot axis an unequal distance compared to the distance between said first end and said pivot axis.
Claim 39
Dependent Claim 63 words
The keyswitch assembly according to claim 30, wherein said key has a longitudinal axis and a transverse axis and said first and second connecting parts have stop means for stopping movement of all of the ends of the levers with respect to said transverse axis and for limiting movement of said second end and said fourth end with respect to said longitudinal axis.
Claim 40
Dependent Claim 30 words
The keyswitch assembly according to claim 30, wherein said key has a longitudinal axis and said second end and said fourth end are slidable with respect to said longitudinal axis.
Claim 41
Dependent Claim 181 words
A keyswitch assembly comprising: a key having a lower surface provided with at least two first connecting parts; a base plate having an upper surface disposed below the key and provided with at least two second connecting parts positioned to correspond to the first connecting parts; a key support comprising a pair of pivotally connected first and second levers, said first lever having a pair of upper ends pivotally coupled to one of the first connecting parts and a pair of lower ends slidingly coupled to one of the second connecting parts and said second lever having a pair of upper end slidingly coupled to another of the first connecting parts and a pair of lower ends pivotally coupled to another of the second connecting parts for supporting the key for perpendicular movement with respect to the base plate, the key support having a downwardly concave space located above the base plate; and a switching member disposed between the key support and the base plate within the downwardly concave space of the key support and actuated for switching said key support.
Claim 42
Dependent Claim 181 words
A keyswitch assembly comprising: a key having a lower surface provided with at least two first connecting parts; a base plate having an upper surface disposed below the key and provided with at least two second connecting parts positioned to correspond to the first connecting parts; a key support comprising a pair of pivotally connected first and second levers, said first lever having a pair of upper ends pivotally coupled to one of the first connecting parts and a pair of lower ends slidingly coupled to one of the second connecting parts and said second lever having a pair of upper end slidingly coupled to another of the first connecting parts and a pair of lower ends pivotally coupled to another of the second connecting parts for supporting the key for perpendicular movement with respect to the base plate, the key support having a downwardly concave space located above the base plate; and a switching member disposed between the key support and the base plate within the downwardly concave space of the key support and actuated for switching said key support.
Claim 43
Dependent Claim 42 words
The keyswitch assembly according to claim 38, wherein the key support comprises a scissors-type linkage with a pivot axis, the switching member being disposed directly below the pivot axis so as to be operated for switching action when the key is depressed.
Claim 44
Dependent Claim 45 words
The keyswitch assembly according to claim 39, wherein the pair of upper ends of the first lever and the pair of lower ends of the second lever are longitudinally immovable and aligned along a plane generally perpendicular to the upper surface of the base plate.
Claim 45
Dependent Claim 43 words
The keyswitch assembly according to claim 39, wherein the pair of upper ends of the first lever, the pair of lower ends of the first lever and the pair of lower ends of the second lever are equally spaced from the pivot axis.
Claim 46
Dependent Claim 22 words
The keyswitch assembly according to claim 38, wherein the first and second connecting parts have stops which limit movement of the key.
Claim 47
Dependent Claim 133 words
A keyswitch assembly comprising: a key; a base plate disposed under said key; a key support for supporting said key for movement with respect to said base plate, and comprising a first member and a second member joined and forming a scissors-type mechanism with a pivot axis, said first member having a first end connected to said key and a second end connected to said base plate, said second member having a first end connected to said key and a second end connected to said base plate, said first end of said first member and said second end of said second member being longitudinally immovable with respect to said key; and a switching member disposed under said key support and operated by said key support for switching by when said key is depressed.
Claim 48
Dependent Claim 133 words
A keyswitch assembly comprising: a key; a base plate disposed under said key; a key support for supporting said key for movement with respect to said base plate, and comprising a first member and a second member joined and forming a scissors-type mechanism with a pivot axis, said first member having a first end connected to said key and a second end connected to said base plate, said second member having a first end connected to said key and a second end connected to said base plate, said first end of said first member and said second end of said second member being longitudinally immovable with respect to said key; and a switching member disposed under said key support and operated by said key support for switching by when said key is depressed.
Claim 49
Dependent Claim 31 words
The keyswitch assembly according to claim 43, wherein said first end of said first member and said second end of said second member are laterally immovable with respect to said key.
Claim 50
Dependent Claim 37 words
The keyswitch assembly according to claim 43, wherein said first end of said first member, said second end of said first member and said second end of said second member are equally spaced from said pivot axis.
Claim 51
Dependent Claim 45 words
The keyswitch assembly according to claim 45, wherein said first end of said second member is the same distance from said pivot axis as said second end of said first member, wherein said key remains horizontal with respect to the vertical movement of said key.
Claim 52
Dependent Claim 115 words
The keyswitch assembly according to claim 45, wherein said first end of said first member has a pair of opposed ends aligned along a first line connecting said pair of ends, said second end of said first member has a pair of opposed ends aligned along a second line connecting said pair of ends, and said second end of said second member has a pair of ends aligned along a third line connecting said pair of ends, wherein a shortest distance between said first line and said pivot axis, a shortest distance between said second line and said pivot axis and a shortest distance between said third line and said pivot axis are the same.
Claim 53
Dependent Claim 59 words
The keyswitch assembly according to claim 47, wherein said first end of said second member has a pair of opposed ends aligned along a fourth line connecting said pair of opposed ends, and a shortest distance between said fourth line and said pivot axis is the same as said shortest distance between said second line and said pivot axis.
Claim 54
Dependent Claim 46 words
The keyswitch assembly according to claim 45, further comprising a normal axis extending from said key to said base plate, wherein said first end of said first member and said second end of said second member are aligned along a plane parallel to said normal axis.
Claim 55
Dependent Claim 33 words
The keyswitch assembly according to claim 49, wherein said first end of said first member, a center point on said pivot axis and said second end of said first member are linearly aligned.
Claim 56
Dependent Claim 46 words
The keyswitch assembly according to claim 45, further comprising a normal axis extended from said key to said base plate, wherein said first end of said second member and said second end of said first member are aligned along a plane parallel to said normal axis.
Claim 57
Dependent Claim 62 words
The keyswitch assembly according claim 43, wherein said key has at least two first connecting parts and said base plate has at least two second connecting parts, said first end of said first member is pivotally connected to one of said first connecting parts and said second end of said second member is pivotally connected to one of said second connecting parts.
Claim 58
Dependent Claim 43 words
The keyswitch assembly according to claim 52, wherein said first end of said second member is slidably connected to another of said first connecting parts and said second end of said first member is slidably connected to another of said second connecting parts.
Claim 59
Dependent Claim 26 words
The keyswitch assembly according to claim 53, wherein said first and second connecting parts have stop means for stopping lateral movement with respect to the key.
Claim 60
Dependent Claim 33 words
The keyswitch assembly according to claim 43, wherein said switching member is positioned beneath said key support and said key support contacts and compresses said switching member upon vertical movement of said key.
Claim 61
Dependent Claim 69 words
The keyswitch assembly according to claim 55, wherein said second end of said first member has a first pair of opposed ends and said second end of said second member has a second pair of opposed ends, and wherein said first pair of opposed ends and said second pair of opposed ends surround said switching member, and said key support bears on said switching member at said pivot axis.
Claim 62
Dependent Claim 52 words
The keyswitch assembly according to claim 55, wherein said key support includes a bearing surface located at said pivot axis for bearing on said switching member and said bearing surface has at least two surfaces disposed at an obtuse angle to each other on each said first member and said second member.
Claim 63
Dependent Claim 21 words
The keyswitch assembly according to claim 57, wherein said key support comprises a polygonal body for bearing on said switching member.
Claim 64
Dependent Claim 43 words
The keyswitch assembly-according to claim 43, wherein said key support has a downwardly concave space located above said base plate and said switching member is disposed between said key support and said base plate within said downwardly concave space of said key support.
Claim 65
Dependent Claim 93 words
The keyswitch assembly according to claim 43, wherein said first end of said first member has a first pair of opposed ends, said first end of said second member has a second pair of opposed ends, said second end of said second member has a third pair of opposed ends and said second end of said first member has a fourth pair of opposed ends, and wherein said first, second, third and fourth pair of opposed ends form an area surrounded by their ends, and said switching member is positioned within said area.
Claim 66
Dependent Claim 23 words
The keyswitch assembly according to claim 43, wherein said first member is a first lever and said second member is a second lever.
Claim 67
Dependent Claim 30 words
The keyswitch assembly according to claim 43, wherein said first end, said second end and said pivot axis of each of said first and said second members are linearly aligned.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-01-17 1997-07-19 1998-01-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-01-17 2001-07-19 2002-01-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-01-17 2005-07-19 2006-01-18 $7700.00 Window Closed / Lapsed

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