US4771143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diaphragm keyboard
Assignee: Wilhelm Ruf KG
•
Filing: 1987-04-16
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Granted: 1988-09-13
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Expires: 2007-04-16
Abstract
Abstract The diaphragm keyboard comprises a baseboard from the bottom of which pins (11) project in vertical direction. These pins (11) pass through apertures (22) in an encoding plate (20) and extend beyond the surface thereof, thus presenting spacers for a diaphragm (30). In addition, they serve for retaining and aligning the encoding plate (20).
Inventors
- 👤 Horst Hoffmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:17
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/70; H01H13/78; H01H13/80; H01H13/702; H01H13/703; H01H2201/00; H01H2201/008; H01H2203/00; H01H2203/032; H01H2209/00; H01H2209/01; H01H2209/014; H01H2211/00; H01H2211/006; H01H2211/02; H01H2229/00; H01H2229/036; H01H2229/042
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
109 words
A diaphragm keyboard having a baseboard, an encoding plate arranged on top of the baseboard and including electrical switch contact surfaces, and a flexible diaphragm which is arranged spaced from and opposed to the encoding plate and includes electrically conductive areas at least opposite the electrical switch contact surfaces wherein the encoding plate comprises apertures which are located laterally next to the switch contact surfaces and through which extend pins of electrically non-conductive material, wherein the pins stretch from the baseboard to the diaphragm, protruding beyond the encoding plate, and wherein said pins serve as spacers holding said diaphragm is a spaced-apart relationship with respect to said encoding plate.
Claim 2
Dependent Claim
109 words
A diaphragm keyboard having a baseboard, an encoding plate arranged on top of the baseboard and including electrical switch contact surfaces, and a flexible diaphragm which is arranged spaced from and opposed to the encoding plate and includes electrically conductive areas at least opposite the electrical switch contact surfaces wherein the encoding plate comprises apertures which are located laterally next to the switch contact surfaces and through which extend pins of electrically non-conductive material, wherein the pins stretch from the baseboard to the diaphragm, protruding beyond the encoding plate, and wherein said pins serve as spacers holding said diaphragm is a spaced-apart relationship with respect to said encoding plate.
Claim 3
Dependent Claim
18 words
The diaphragm keyboard as claimed in claim 1 wherein the diaphragm is made of homogeneous, electrically conductive material.
Claim 4
Dependent Claim
46 words
The diaphragm keyboard as claimed in claim 1 wherein the pins (11) have upper and lower end faces and sidewalls (15) of the baseboard (10) have an upper end face, said end face being in a plane with the upper end faces of the pins (11).
Claim 5
Dependent Claim
33 words
The diaphragm keyboard as claimed in claim 3 wherein the sidewalls of the baseboard have a thickened head formed with a chamber which is inclined inwardly towards the sidewall at an opposite side.
Claim 6
Dependent Claim
17 words
The diaphragm keyboard as claimed in claim 1 wherein the pins are joined integrally with the baseboard.
Claim 7
Dependent Claim
23 words
The diaphragm keyboard as claimed in claim 5 wherein each pin has a thickened head which laterally overlaps the containing said pin aperture.
Claim 8
Dependent Claim
25 words
The diaphragm keyboard as claimed in claim 6 wherein the apertures and the pins are disposed axially symmetrically with respect to the switch contact surfaces.
Claim 9
Dependent Claim
25 words
The diaphragm keyboard as claimed in claim 5 wherein the apertures and the pins are disposed axially symmetrically with respect to the switch contact surfaces.
Claim 10
Dependent Claim
33 words
The diaphragm keyboard as claimed in claim 8 wherein the apertures and pins are arranged in a uniform matrix such that they lie on intersections of diagonals which contact adjacent switch contact surfaces.
Claim 11
Dependent Claim
53 words
The diaphragm keyboard as claimed in claim 8 wherein the apertures and pins are arranged in a uniform matrix such that they lie on straight lines which connect the switch contact surfaces in rows and columns, the apertures and pins furthermore being uniformly spaced from centers of respective next adjacent switch contact surfaces.
Claim 12
Dependent Claim
27 words
The diaphragm keyboard as claimed in claim 5 wherein adhesive material is provided between the inner diameter of the apertures and the outer diameter of the pins.
Claim 13
Dependent Claim
25 words
The diaphragm keyboard as claimed in claim 11 wherein the apertures and the pins are disposed axially symmetrically with respect to the switch contact surfaces.
Claim 14
Dependent Claim
39 words
The diaphragm keyboard as claimed in claim 11 wherein the apertures and pins are arranged around respective switch contact surfaces such that connecting lines form a triangle in which is located a center of a corresponding switch contact surface.
Claim 15
Dependent Claim
34 words
The diaphragm keyboard as claimed in claim 13 wherein the baseboard comprises webs which project vertically from its bottom, pins each protruding above an upper edge of the webs at intersections of the webs.
Claim 16
Dependent Claim
19 words
The diaphragm keyboard as claimed in claim 14 wherein the diaphragm is electrically conductive at its entire bottom surface.
References Cited (Backward Citations)
US3600528A
Cited
US4128744A
Cited
US4375585A
Cited
FR2541523A1
Cited
US4580018A
Cited
US4489227A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |