Solid state keyboard
First Claim
1. In combination,a housing constructed of a depressible material to define individual areas for depression to identify individual indicia,a first electrically insulating material adhered to the housing at the individual areas of the housing to transmit strains produced in the housing by the depression of the housing at the individual areas in the housing,a plurality of thin sheets of an electrically insulating material each attached to the first insulating material at a position corresponding to an individual one of the areas in the housing and depressible to transmit strains,a plurality of thin sheets of an electrically conductive material each adhered to an individual one of the electrically insulating sheets at one of the individual areas of the housing and depressible to transmit strains,a plurality of crystals having first and second flat surfaces, each of the crystals being adhered at its first flat surface to an individual one of the electrically conductive sheets at one of the individual areas of the housing and being depressible to produce an electrical signal of the second flat surface of the crystal,a second insulating material adhered to the second surfaces of the crystals and having properties less hard than the properties of the first insulating material, andmeans operatively coupled to the crystals to convert the signals from the crystals to electrical signals having an impedance less than that provided by the crystals.
1 Assignment
0 Petitions
Accused Products
Abstract
A housing, preferably electrically conductive, defines individual areas for depression to identify individual indicia, e.g., number, alphabetical letters. A hard, electrically insulating material attached to the housing transmits strains produced by the depression of the individual areas on the housing. A plurality of thin electrically insulating sheets are attached to the hard insulating material at the individual areas in the housing. A plurality of thin electrically conductive sheets attached to the thin insulating sheets. The insulating sheets and the conductive sheets may constitute printed circuit segments. A plurality of ceramic crystals are attached to individual ones of the conductive sheets. The electrically conductive sheets are preferably coupled electrically to the housing. This causes one surface of each crystal to be common to the adjacent area. When the keyboard is depressed in the adjacent keyboard area, each crystal becomes stressed and causes an electrical signal to be generated on the ungrounded surface of the crystal.
16 Citations
34 Claims
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1. In combination,
a housing constructed of a depressible material to define individual areas for depression to identify individual indicia, a first electrically insulating material adhered to the housing at the individual areas of the housing to transmit strains produced in the housing by the depression of the housing at the individual areas in the housing, a plurality of thin sheets of an electrically insulating material each attached to the first insulating material at a position corresponding to an individual one of the areas in the housing and depressible to transmit strains, a plurality of thin sheets of an electrically conductive material each adhered to an individual one of the electrically insulating sheets at one of the individual areas of the housing and depressible to transmit strains, a plurality of crystals having first and second flat surfaces, each of the crystals being adhered at its first flat surface to an individual one of the electrically conductive sheets at one of the individual areas of the housing and being depressible to produce an electrical signal of the second flat surface of the crystal, a second insulating material adhered to the second surfaces of the crystals and having properties less hard than the properties of the first insulating material, and means operatively coupled to the crystals to convert the signals from the crystals to electrical signals having an impedance less than that provided by the crystals.
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6. In combination,
a housing made from an electrically conductive material and having a plurality of spaced areas each for identifying an individual symbol, the housing being constructed of a depressible material to be depressed at the individual ones of the spaced areas in the plurality and to become strained in such individual ones of such spaced areas by such depressions, a plurality of crystals each disposed in spaced but adjacent relationship to an individual one of the spaced areas on the housing and having first and second opposite surfaces, the crystals being constructed to be depressed and to produce electrical signals upon such depression, a plurality of means for retaining the crystals in the plurality in spaced but adjacent relationship to the housing for insulating such crystals from the housing and for transmitting to the crystals the strains imposed in the housing by the depression of the housing at the individual ones of the spaced areas in the housing for generation of the signals by the crystals, a plurality of electrically conductive means each disposed between an adjacent one of the retaining means in the plurality and an adjacent one of the crystals in the plurality and electrically connected to the housing for electrically grounding the first surface of the adjacent crystals and adhered to the adjacent one of the retaining means in the plurality and the adjacent one of the crystals in the plurality, the housing, the crystals in the plurality, the retaining means in the plurality and the electrically conductive means in the plurality being constructed and disposed, for each of the crystals in the plurality, at the associated one of the spaced areas in the housing to define successive layers without any voids, and converting means responsive to the signals from the second surfaces of the crystals for producing signals of lower impedance than the impedance of the signals produced in the crystals.
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13. In combination,
a housing having a plurality of spaced areas each for identifying an individual symbol, the housing being constructed to be depressed at individual ones of the spaced areas to become strained at such spaced areas in accordance with such depressions, a plurality of crystals each formed from a thin sheet of material and each associated with the housing at an individual one of the spaced areas in the housing and each constructed to produce electrical signals in accordance with strains imposed upon the crystals, means defining an electrically grounded plane for one surface of each sheet defining one of the crystals in the plurality, first electrically insulating means disposed between the means defining the electrically grounded plane and the housing at individual ones of the spaced areas in the housing and adhering the means defining the electrically grounded plane to the housing at such individual ones of the spaced areas in the housing and providing for a transmission to associated ones of the crystals of stresses imposed upon the housing at such individual areas of the housing, an electrically insulating material disposed between the housing and the first electrically insulating means and adhered to the housing and the first insulating means and having properties of transmitting to the first insulating mean the stresses imposed upon the housing at the spaced areas of the housing upon the depression of the housing at such spaced areas, means disposed between the means defining the electrically grounded plane and the crystals in the plurality for adhering each of the crystals in the plurality to the means defining the electrically grounded plane in electrically conductive relationship with the means defining the electrically grounded plane, means for providing for the transmittal from the ungrounded terminals of the associated crystals in the plurality of electrical signals in accordance with the depression of the housing at the individual areas of the housing, the housing, the means defining the ground plane, the electrically insulating means and the adhering means being constructed and disposed, for each of the crystals in the plurality, at the associated one of the spaced areas in the housing to define successive layers without any voids, and means responsive to the transmitted signals for producing electrical signals having a lower impedance than the impedance of the signals produced by the crystals.
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15. In combination,
a housing having a plurality of spaced areas each for identifying an individual symbol, the housing being constructed to be depressed at individual ones of the spaced areas to become strained at such spaced areas in accordance with such depressions, a plurality of crystals each formed from a thin sheet of material and each associated with the housing at an individual one of the spaced areas in the housing and each constructed to produce electrical signals in accordance with strains imposed upon the crystals, means defining an electrically grounded plane for one surface of each sheet defining one of the crystals in the plurality, first electrically insulating means disposed between the means defining the electrically grounded plane and the housing at individual ones of the spaced areas in the housing and adhering the means defining the electrically grounded plane to the housing at such individual ones of the spaced areas in the housing and providing for a transmission to associated ones of the crystals of stresses imposed upon the housing at such individual areas of the housing, an electrically insulating material disposed between the housing and the first electrically insulating means and adhered to the housing and the first insulating means and having properties of transmitting to the first insulating means the stresses imposed upon the housing at the spaced areas of the housing upon the depression of the housing at such spaced areas, means disposed between the means defining the electrically grounded plane and the crystals in the plurality for adhering each of the crystals in the plurality to the means defining the electrically grounded plane in electrically conductive relationship with the means defining the electrically grounded plane, means for providing for the transmittal from the ungrounded terminals of the associated crystals in the plurality of electrical signals in accordance with the depression of the housing at the individual areas of the housing, the housing, the means defining the ground plane, the electrically insulating means and the adhering means being constructed and disposed, for each of the crystals in the plurality, at the associated one of the spaced areas in the housing to define successive layers without any voids, means responsive to the transmitted signals for producing electrical signals having a lower impedance then the impedance of the signals produced by the crystals, the transmittal means including second insulating means less hard than the first insulating means, the second insulating means being adhered to the crystals in the plurality and covering the crystals in the plurality, and a plurality of insulating means each defining a backing for the electrically grounded plane and each disposed between the electrically insulating means and the electrically grounded plane and each adhered to the electrically insulating means and the electrically grounded plane and each providing an insulation for an individual one of the crystals without any voids and each disposed and constructed to transmit strains from the housing at an individual one of the spaced areas in the housing to an associated one of the crystals in the plurality
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18. In combination,
a housing constructed to define a particular area for depression to identify an individual indicium, a first electrically insulating material having hard properties and adhered to the housing in abutting relationship with the particular area in the housing to transmit strains produced in the housing by the depression of the housing at the particular area in the housing, a thin sheet of an electrically insulating material adhered to the first insulating material at a position corresponding to the particular area in the housing and constructed to transmit strains produced in the housing at the particular area in the housing, a thin sheet of an electrically conductive material adhered to the electrically insulating sheet at a position corresponding to the particular area in the housing and constructed to transmit strains produced in the housing by the depression of the housing at the particular area in the housing, a crystal having a first surface adhered to the electrically conductive sheet in an electrically conductive relationship with the sheet and constructed to be strained and to produce an electrical signal when strained, a second insulating material attached to the crystal and having properties less hard than that of the first insulating material, and means operatively coupled to the crystal to convert the signals from the crystal to electrical signals having an impedance lower than the impedance provided by the signals in the crystal.
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23. In combination,
a housing having a particular area depressible to produce strains in the housing to identify an individual symbol. a crystal disposed in spaced but adjacent relationship to the particular area on the housing to become strained upon the depression of the particular area in the housing to produce an electrical signal in accordance with such strain, electrically conductive means disposed between the crystal and the housing and defining a ground plane, means for retaining the crystal and the electrically conductive means in spaced but adjacent relationship to the housing at the particular area in the housing and the crystal and for insulating the crystal from the housing and for transmitting to the crystal any strains imposed in the housing by the depression of the housing at the particular area in the housing for the generation of signals by the crystal, the retaining means including an electrically insulating material adhered to the housing at the particular area in the housing and having properties of transmitting to the electrically conductive means and the crystal the stresses imposed upon the housing at the particular area by the depression of the housing at the particular area, and converting means responsive to the signals from the crystal for producing signals of lower impendace than those produced by the crystal.
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30. In combination,
an electrically conductive housing having a particular area depressible to produce strains in the housing to identify an individual symbol, a crystal formed from a thin sheet defined by first and second opposite surfaces and constructed to be strained to produce electrical signals, means operatively coupled to the first surface of the crystal and electrically connected to the housing to define an electrically grounded plane for the first surface of the crystal and constructed to transmit to the crystal the stresses imposed upon the housing at the particular area of the housing, a first electrically insulating material adhered to the housing at the particular area in the housing without voids and providing for a transmission to the crystal of stresses imposed upon the housing at the particular area of the housing by the depression of the housing in the particular area, a backing sheet made from an electrically insulating material and disposed between the first insulating material and the means defining the ground plane in adhered relationship to the first insulating means and the means defining the ground palne, means for providing for the transmittal of electrical signals from the ungrounded terminal of the crystal, and means responsive to the transmitted signals for producing electrical signals having a lower impedance than the impedance of the signals produced in the crystal.
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32. In combination,
an electrically conductive housing having a particular area depressible to produce strains in the housing to identify an individual symbol, a crystal formed from a thin sheet defined by first and second opposite surfaces and constructed to be strained to prdouce electrical signals, means operatively coupled to the first surface of the crystal and electrically connected to the housing to define an electrically grounded plane for the first surface of the crystal and constructed to transmit to the crystal the stresses imposed upon the housing at the particular area of the housing, first electrically insulating means disposed between the means defining the ground plane and the particular area in the housing and providing for the adherence of the means defining the ground plane to the particular area in the housing without voids and providing for a transmission to the crystal of stresses imposed upon the housing at the particular area of the housing by the depression of the housing in the particular area, a backing sheet made from an electrically insulating material and disposed between the first insulating means and the means defining the ground plane in adhered relationship to the first insulating means and the means defining the ground plane, means for providing for the transmittal of electrical signals from the ungrounded terminal of the crystal, means responsive to the transmitted signals for producing electrical signals having a low impedance than the impedance of the signals produced in the crystal, the means defining the ground plane constituting an electrically conductive sheet and the backing sheet and the electrically conductive sheet constituting a printed circuit, and the transmittal means including an electrically insulating layer adhered to the ungrounded terminal of the crystal and having properties less hard than the properties of the first insulating material.
Specification