US4352959A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for visual display of telephone operation symbols
Assignee: TE Connectivity Germany GmbH
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Filing: 1980-11-20
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Granted: 1982-10-05
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Expires: 2000-11-20
Abstract
Abstract In accordance with the invention there is provided a display device for visual display of telephone operation symbols in telecommunication apparatus which includes, for example, a key-dialing block. The device has a display element incorporated in a key-dialing block and an electronic circuit controlling the display element. The device is such as to provide a visual display showing a first symbol when one telephone set in a two set circuit is in use while displaying a second symbol when a number is dialed with the receiver replaced.
Inventors
- 👤 Gunter Warnecke
- 👤 Gerhard Schiller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:58
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/247; H04M1/02; H04M1/23; H04M3/00; H04M3/60; H04M3/62; H04M1/0295
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
159 words
A device for visual display of telephone operation symbols in telecommunication apparatus comprising a two-set installation having a free-speaking or loudspeaker option permitting dialing with the receiver replaced, said device comprising: a key-dialing block having a plurality of keys thereon; a liquid crystal display element incorporated in said key-dialing block in the form of one of said keys; and an electronic circuit coupled to said display element for control thereof, said circuit also being coupled to said key-dialing block and said telephone sets; whereby under control of said circuit, said display element shows a first symbol when one of said telephone sets is in use, and shows a second symbol when said key-dialing block is employed to dial a number with the receiver replaced, said circuit comprising: an oscillator coupled to said display element; and means responsive to current flow in said one telephone set for enabling said oscillator, thereby energizing said display element to provide said first symbol.
Claim 2
Independent Claim
159 words
A device for visual display of telephone operation symbols in telecommunication apparatus comprising a two-set installation having a free-speaking or loudspeaker option permitting dialing with the receiver replaced, said device comprising: a key-dialing block having a plurality of keys thereon; a liquid crystal display element incorporated in said key-dialing block in the form of one of said keys; and an electronic circuit coupled to said display element for control thereof, said circuit also being coupled to said key-dialing block and said telephone sets; whereby under control of said circuit, said display element shows a first symbol when one of said telephone sets is in use, and shows a second symbol when said key-dialing block is employed to dial a number with the receiver replaced, said circuit comprising: an oscillator coupled to said display element; and means responsive to current flow in said one telephone set for enabling said oscillator, thereby energizing said display element to provide said first symbol.
Claim 3
Dependent Claim
66 words
A device as claimed in claim 1 in which said means responsive to current flow is a resistor through which said current flows when said one telephone set is in use, and capacitor means connected across said resistor, said oscillator comprising a transformer and at least one transistor connected to said transformer and to said capacitor means, and circuit means energizing said display from said transformer.
Claim 4
Dependent Claim
31 words
Apparatus according to claim 2 in which said oscillator includes two complementary transistors connected to said transformer in a circuit which oscillates for either direction of current flow through said resistor.
Claim 5
Dependent Claim
52 words
A device as claimed in claim 1 or 2 in which contacts are provided which are actuated when dialling with the receiver replaced is to be effected, said contacts controlling the supply of power from a stabilised supply to a logic inverter oscillator connected to the display to energise said second symbol.
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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) | 1985-10-04 | 1986-04-05 | 1986-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-04 | 1990-04-05 | 1990-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-04 | 1994-04-05 | 1994-10-05 | $7700.00 | Window Closed / Lapsed |