US4074261A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keyboard contact and signal line arrangement
Assignee: US Philips Corp
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Filing: 1975-05-01
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Granted: 1978-02-14
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Expires: 1995-05-01
Abstract
Abstract The invention relates to a keyboard comprising at least three contact points per key. One of a group of signal connections is always alternately connected to a group of keys. Each key is then alternately connected to one signal connection of said group. At least three of such groups are present so as to obtain a comparatively low value for the ratio of the number of signal connections to the number of keys.
Inventors
- 👤 Hendrik van der Gaag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:21
CPC Classifications
H; H03; H03M; H03M11/00; H03M11/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
186 words
A keyboard comprising a plurality of key elements, signal connection lines, a plurality of contact points for each of said key elements, each of said contact points including a drive contact point, wherein said contact points may be coupled to each other by means of an actuated key, said contact points of different ones of said key elements being selectively connected to each other by said signal connection lines for the transport of a drive contact signal, wherein for a predetermined number of correspondingly constructed key elements, said predetermined number being equal to the product, n×m×p, of three non-negative integers, there are provided n + m + p signal connection lines, each signal connection line of a group of n, m, and p signal connections, respectively, being selectively connected to a corresponding contact point of at most m × p, at most n × p, and at most m × n, key elements, respectively, each key element being connected to a single signal connection line of each of the groups of n, m and p signal connections, wherein n, m and p are predetermined non-negative integers.
Claim 2
Dependent Claim
186 words
A keyboard comprising a plurality of key elements, signal connection lines, a plurality of contact points for each of said key elements, each of said contact points including a drive contact point, wherein said contact points may be coupled to each other by means of an actuated key, said contact points of different ones of said key elements being selectively connected to each other by said signal connection lines for the transport of a drive contact signal, wherein for a predetermined number of correspondingly constructed key elements, said predetermined number being equal to the product, n×m×p, of three non-negative integers, there are provided n + m + p signal connection lines, each signal connection line of a group of n, m, and p signal connections, respectively, being selectively connected to a corresponding contact point of at most m × p, at most n × p, and at most m × n, key elements, respectively, each key element being connected to a single signal connection line of each of the groups of n, m and p signal connections, wherein n, m and p are predetermined non-negative integers.
Claim 3
Dependent Claim
53 words
A keyboard as claimed in claim 1, wherein said keyboard forms part of a series of q keyboards which are arranged together, each said contact points being selectively connected to a one of said signal connections lines of a group of q of said signal connection lines, where q is a positive integer.
Claim 4
Dependent Claim
63 words
A keyboard as claimed in claim 1 wherein said key elements are arranged in rows and columns, wherein all of said keys of at least two of said rows have one contact connected to one of said m signal connection lines, and all of said keys of at least two columns have one contact connected to one of said n signal connection lines.
Claim 5
Dependent Claim
51 words
A keyboard as claimed in claim 1, further comprising an interrogation device having m outputs which are alternately connected to one of said m signal connections and are individually, interrogated, for each one of said keys each time one of said m signal connections is connected to a drive contact point.
References Cited (Backward Citations)
US3886335A
Cited
US3950743A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |