US3699294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keyboard, digital coding, switch for digital logic, and low power detector switches
Assignee: FLEX-KEY Corp
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Filing: 1971-05-18
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Granted: 1972-10-17
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Expires: 1991-05-18
Abstract
Abstract Electric switches are described in which a resilient, electrically conductive, elastomeric member is spaced adjacent but apart from contact means; among features are the elastomeric connector: of sheet form; on metal contacts as a movable contact bridge; defining a simple and durable multiple switch array including a keyboard, a digital coding assembly and a detector; and as the means, especially with proper selection of distributed conductive particles in the elastomer for limited conductivity, of eliminating the electrical effects of bounce in solid state electronic logic circuitry and the like. Fabrication of the switch as a simple, thin compact laminate using printed circuit boards is shown using the preferred silicone elastomer and carbon filler. In preferred embodiments pressure against conductive elastomer sheet means will cause it to connect to a contact element conductively and release of pressure will cause the sheet means to disconnect. The sheet means can be used as a floating connection for one or more circuit elements, and in this form has particular application in a keyboard assembly, particularly in connection with replaceable printed circuit boards and in digital coding techniques with a single printed circuit board. Preferably, the sheet means resiliently, reversibly deforms from first to second conditions, typically engaging the contacts in the deformed or bulged condition. Preferably in one condition the sheet means takes a planar form, positioned by a spacer layer from the contacts. And preferably the contacts are elements of a printed circuit.
Inventors
- 👤 William B Sudduth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:18
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/70; H01H13/78; H01H13/785; H01H1/00; H01H1/02; H01H1/021; H01H1/029; H01H13/702; H01H13/703; H01H2201/00; H01H2201/016; H01H2201/022; H01H2201/032; H01H2209/00; H01H2209/014; H01H2209/024; H01H2209/03; H01H2209/046; H01H2209/052; H01H2209/068; H01H2209/074; H01H2209/078; H01H2215/00; H01H2215/002; H01H2217/00; H01H2217/006; H01H2217/012; H01H2217/016; H01H2223/00; H01H2223/002; H01H2223/034; H01H2223/036; H01H2223/046; H01H2223/052; H01H2225/00; H01H2225/018; H01H2227/00; H01H2227/002; H01H2227/012; H01H2229/00; H01H2229/022; H01H2229/024; H01H2229/028; H01H2231/00; H01H2231/002; H01H2231/038; H01H2231/05; H01H2239/00; H01H2239/026
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
11 words
The switch of claim 1 wherein said elastomer is carbon filled.
Claim 2
Dependent Claim
21 words
The switch of claim 1 wherein said sheet means has substantially the electrical resistance of carbon filled silicone and fluorosilicone elastomers.
Claim 3
Dependent Claim
115 words
An electric switch for producing a signal for use by solid state electronic digital logic circuitry, said switch comprising at least one pair of contact elements and a resilient, movable electrically conductive bridge means made of elastomer with conductive particles distributed therethrough, said bridge means spaced adjacent but apart from said elements so that motion of said bridge means against said elements will cause said elements to be connected conductively through the particle-containing elastomer to provide a bridging conductive path and reverse movement of said bridge means will cause said bridge means to disconnect from said elements and open the path between the elements, the switch enabling production of a signal without electrical bounce effects.
Claim 4
Dependent Claim
19 words
The switch of claim 4 wherein said particles are of nonmetallic conductive material, limiting the conductivity of said path.
Claim 5
Dependent Claim
14 words
The switch of claim 5 wherein said particles comprise carbon filler in said elastomer.
Claim 6
Dependent Claim
61 words
The switch of claim 4 wherein said elements comprise printed circuits secured to a printed circuit board, and non-moving portions of elastomer integral with said bridge means are supported by said board in an insulated condition relative to said printed circuits, said portions retaining said bridge means in said spaced position in the absence of pressure applied against said bridge means.
Claim 7
Dependent Claim
67 words
The switch of claim 4 wherein neighboring portions of elastomer integral with said bridge means extend to various sides of said bridge means and, together with said bridge means comprising a sheet means, the direction of movement of said bridge means being normal to the direction of extent of the sheet means and the conductivity path between said contact elements being in the direction of said extent.
Claim 8
Dependent Claim
24 words
The switch of claim 8 wherein the elastomer portion defining said bridge means is sized for deflection by a finger of the human hand.
Claim 9
Dependent Claim
93 words
An electric switch comprising in combination contact means, resilient, flexible electrically conductive sheet means of electrically conductive elastomer and positioning means positioning said sheet means so that a first portion of said sheet means is adjacent but apart from said contact means, and said first portion free to move relative to neighboring portions of said sheet means whereby pressure applied against said first portion will cause it to connect to said contact means conductively, and release of said pressure will cause said portion of said sheet means to disconnect from said contact means.
Claim 10
Dependent Claim
26 words
The electric switch of claim 10 wherein said neighborinG portions support said first portion in said spaced apart position in the absence of external operating pressure.
Claim 11
Dependent Claim
51 words
The electric switch of claim 10 wherein there are a plurality of electrical contact elements, said sheet means including a plurality of sheet portions positioned over respective electrical contact elements, said respective portions being free to move and press against respective contact elements in response to pressure applied to said portions.
Claim 12
Dependent Claim
16 words
The electric switch of claim 12 wherein said contact elements comprise part of a printed circuit.
Claim 13
Dependent Claim
45 words
The switch of claim 12 useful as a detector wherein said contact elements when connected by said sheet means all complete the same circuit to a pair of terminals whereby pressure at any of said portions of said sheet means can complete the same circuit.
Claim 14
Dependent Claim
20 words
The switch of claim 10 adapted for manual pressure on said portion, said portion being covered by an insulating layer.
Claim 15
Dependent Claim
20 words
The switch of claim 15 wherein said insulating layer is in the form of a button accessible to the finger.
Claim 16
Dependent Claim
52 words
The switch of claim 16 wherein said insulating layer comprises an elastomer forming a button shape, said button shape being resiliently deformable, providing for travel of the finger between the time of contact with such button and the time the button is deformed against said sheet means sufficient to apply actuating pressure.
Claim 17
Dependent Claim
13 words
The switch of claim 17 wherein said button is a hollow, thin-walled member.
Claim 18
Dependent Claim
27 words
The switch of claim 15 including an outer member having an opening exposing to the finger said insulating layer for application of actuating pressure to said portion.
Claim 19
Dependent Claim
87 words
An electric switch assembly comprising in combination a non-conductive base carrying a printed circuit means which defines circuit contact elements at a spaced plurality of locations; portions of electrically conductive, resilient elastomer; means positioning elastomer portions adjacent but apart from respective contact elements; the respective elastomer portions being free to move and press against the respective contact elements in response to pressure applied to said portions, said switch adapted for actuation by externally applied pressure on said portions, said portions associated with outer insulative pressure transmitting means.
Claim 20
Dependent Claim
45 words
The electric switch of claim 20 wherein said elastomer portions comprise carbon filled elastomer, so that pressure applied against a said portion will cause it to connect said element with limited conductivity and release of pressure will cause said portion to disconnect from said element.
Claim 21
Dependent Claim
21 words
The electric switch of claim 20 wherein said elastomer comprises a homogeneous body of elastomer and electrically conductive particles distributed therethrough.
Claim 22
Dependent Claim
51 words
The switch assembly of claim 20 wherein each movable portion of conductive elastomer is integral with neighboring portions of elastomer held so that resilient deflection of said elastomer occurs between said movable and neighboring portions during application of said externally applied pressure, providing a return force upon release of said pressure.
Claim 23
Dependent Claim
78 words
An electric switch comprising in combination at least one pair of circuit contact elements and a resilient, flexible, electrically conductive, elastomeric sheet means of electrically conductive silicone elastomer spaced adjacent but apart from said elements so that pressure applied against said sheet means will cause it to connect said elements conductively thus providing a bridging conductive path and release of pressure will cause said sheet means to disconnect from said elements and open the path between the elements.
Claim 24
Dependent Claim
91 words
A keyboard assembly comprising in combination resilient, flexible, electrically conductive, elastomeric sheet means, an insulating separator sheet below said conductive sheet means, and an electrical circuit board below said separator sheet and having contact elements; said separator sheet having openings registrable with said elements so that pressure applied aGainst the portion of said conductive sheet means above an opening will cause it to press against a said element causing it to connect to said element conductively, and release of said pressure will cause said sheet means to disconnect from said element.
Claim 25
Dependent Claim
113 words
A keyboard assembly comprising in combination resilient, flexible, electrically conductive, elastomeric sheet means, an insulating separator sheet below said conductive sheet means, and an electrical circuit board below said separator sheet and having a plurality of pairs of spaced contact elements; said separator sheet having openings registrable with said pairs of elements so that pressure applied against the portion of said conductive sheet means above an opening will cause it to press against the pair of contact elements causing it to connect said elements conductively thus providing a bridging conductive path, and release of said pressure will cause said conductive portion to disconnect from said elements and open the path between the elements.
Claim 26
Dependent Claim
29 words
The keyboard assembly of claim 26 wherein said conductive sheet means is provided on its outer surface with an insulating layer at least in the area of said openings.
Claim 27
Dependent Claim
22 words
The keyboard assembly of claim 26 wherein said conductive means is provided on its outer surface with buttons registrable with said openings.
Claim 28
Dependent Claim
103 words
A digital coding assembly comprising in combination a resilient, flexible, electrically conductive elastomeric sheet means, an insulating separator layer below said sheet means and having a selected pattern of apertures and an electrical circuit board below said layer and having on its upper surface a common circuit element interlaced with a plurality of individual circuit elements, pressure applied against the portion of the conductive sheet means above the pattern of apertures causing that portion to provide a bridging conductive path from the common circuit element to each circuit element exposed by the apertures and release of said pressure causing opening of said path.
Claim 29
Dependent Claim
19 words
The device of claim 29, wherein the conducting pattern for all said circuit elements is on said upper surface.
Claim 30
Dependent Claim
31 words
The device of claim 29 wherein said common circuit element comprises a series of parallel branches with each said individual circuit element being disposed between a different pair of said branches.
Claim 31
Dependent Claim
34 words
The device of claim 29 wherein all apertures are arranged so that one special circuit element is always connected to the common element by depression of the conductive sheet means at any actuation point.
Claim 32
Dependent Claim
31 words
The device of claim 32 wherein apertures which provide contact with said special element are smaller than the unit aperture for the other circuit elements, thus providing for a delayed action.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |