Patent US4636585A successfully refreshed from Google Patents.
US4636585A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone installations
Assignee: Geobra Brandstaetter GmbH and Co KG
•
Filing: 1984-07-05
•
Granted: 1987-01-13
•
Expires: 2004-07-05
Abstract
Abstract A telephone installation has two talk-listen stations each comprising a telephone case adapted to receive talking and listening means housed in a common receiver case. At least one switch is provided on the telephone case or on the receiver case and is operable as a result of the raising and setting down of the receiver case on the telephone case. Each talk-listen station has a buzzer or like means and the listening means comprises an electroacoustic piezoelectric device with metallic electrodes arranged on either side of a piezoelectric material plate, one electrode being subdivided into two partial electrodes which are not interconnected in direct current-like manner. An oscillator arrangement is provided between the partial electrodes and the other electrode which produces a dial tone in one switching position of a switch and in the other switching position one of the partial electrodes and the said other electrode form the actual listening means, the other partial electrode being disconnected.
Inventors
- 👤 Horst Brandstatter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:29
CPC Classifications
H; H04; H04R; H04R17/00; H04M; H04M1/00; H04M1/02; H04M1/03; H04M19/00; H04M19/02; H04M19/04; H04M9/00; H04M9/001
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
145 words
A telephone installation having two talk-listen stations each comprising talking and listening means housed in a common receiver case, first switch means being provided, at said receiver case, said first switch means being in a first switching position when the receiver case is resting and in a second switching position when the receiver case is lifted wherein the listening means comprises an electroacoustic piezoelectric device having metallic electrodes arranged on either side of a piezoelectric material plate, one electrode being subdivided into two partial electrodes not interconnected in direct current-like manner, an oscillator arrangement being provided between the partial electrodes and the other electrode which produces a ringing signal in one switching position of said first switch means and in the other switching position, one of the partial electrodes and the said other electrode forming the actual listening means, the other partial electrode being disconnected.
Claim 2
Dependent Claim
145 words
A telephone installation having two talk-listen stations each comprising talking and listening means housed in a common receiver case, first switch means being provided, at said receiver case, said first switch means being in a first switching position when the receiver case is resting and in a second switching position when the receiver case is lifted wherein the listening means comprises an electroacoustic piezoelectric device having metallic electrodes arranged on either side of a piezoelectric material plate, one electrode being subdivided into two partial electrodes not interconnected in direct current-like manner, an oscillator arrangement being provided between the partial electrodes and the other electrode which produces a ringing signal in one switching position of said first switch means and in the other switching position, one of the partial electrodes and the said other electrode forming the actual listening means, the other partial electrode being disconnected.
Claim 3
Dependent Claim
58 words
A telephone installation as claimed in claim 1, in which a second switch means is provided at each talk-listen station, said second switch means being manually operable independently of the first switch means, the oscillator arrangement of the remote talk-listen station being activated if the said first switch means of said station is in the first switching position.
Claim 4
Dependent Claim
48 words
A telephone installation as claimed in claim 2, in which, when the said first switch means of both talklisten stations are in the second switching position an amplifier arrangement in one talk-listen station can be activated while the other talk-listen station converts amplified electrical oscillation into sound waves.
Claim 5
Dependent Claim
18 words
A telephone installation as claimed in claim 1, in which the talking means comprises an electroacoustic piezoelectric device.
Claim 6
Dependent Claim
30 words
A telephone installation as claimed in claim 4, in which each of the piezoelectric devices at each talk-listen station is placed on a respective taut foil in the receiver case.
Claim 7
Dependent Claim
49 words
A telephone installation as claimed in claim 1, in which a plurality of pushbuttons is arranged on each receiver case and on depressing the same a switch plate which is pivotably mounted in the receiver case is moved to close said second switch means of the associated talk-listen station.
References Cited (Backward Citations)
US1830322A
Cited
US1830035A
Cited
US2653192A
Cited
GB1001391A
Cited
US3594515A
Cited
US3617923A
Cited
DE2105502A1
Cited
DE2142841A1
Cited
US3924073A
Cited
US4022976A
Cited
US4251694A
Cited
US4374307A
Cited
FR2496366A1
Cited
US4472602A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-12 | 1990-07-14 | 1991-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-12 | 1994-07-14 | 1995-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-12 | 1998-07-14 | 1999-01-13 | $7700.00 | Window Closed / Lapsed |