US4206318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intraplant communication system
Assignee: Gai Tronics Corp
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Filing: 1978-06-19
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Granted: 1980-06-03
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Expires: 1998-06-19
Abstract
Abstract This invention is an improvement of the intraplant communication system in U.S. Pat. No. 3,527,890. It comprises one base unit composed of a handset amplifier and speaker amplifier, each with its own integral power supply and each located on a common printed circuit board. This unit also features a disconnect device, formerly called a hook switch, which includes a radio frequency proximity detector which has no moving parts.
Inventors
- 👤 Lee W. Steely
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:04
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/60; H04M1/6033; H04M1/02; H04M1/04; H04M1/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
155 words
A telephone communication system including a station connected thereto comprising two relatively movable elements, namely a handset and a hang-up support for said handset, said handset having an audio receiver in one end and a microphone in the other, said handset and hang-up support containing means devoid of movable switching contacts for proximity detection of movement of said handset relative to said hang-up support, said means comprising a proximity radio frequency transmitter contained in the handset, and a proximity receiving antenna contained in the hang up support, and disconnect relay means activated by a proximity detector responsive to said proximity radio frequency transmitter upon movement of said handset to close proximity to said hang-up support, even without hanging said handset thereon, so as to effect electrical disconnection of said handset from said system and so that movement of said handset away from said hang-up support will effect electrical connection of said handset to said system.
Claim 2
Dependent Claim
155 words
A telephone communication system including a station connected thereto comprising two relatively movable elements, namely a handset and a hang-up support for said handset, said handset having an audio receiver in one end and a microphone in the other, said handset and hang-up support containing means devoid of movable switching contacts for proximity detection of movement of said handset relative to said hang-up support, said means comprising a proximity radio frequency transmitter contained in the handset, and a proximity receiving antenna contained in the hang up support, and disconnect relay means activated by a proximity detector responsive to said proximity radio frequency transmitter upon movement of said handset to close proximity to said hang-up support, even without hanging said handset thereon, so as to effect electrical disconnection of said handset from said system and so that movement of said handset away from said hang-up support will effect electrical connection of said handset to said system.
Claim 3
Dependent Claim
21 words
A telephone communication system as recited in claim 1 wherein said transmitter is tuned to a frequency of approximately 39 Khz.
Claim 4
Dependent Claim
57 words
A telephone communication system as recited in claim 1 wherein said proximity radio frequency transmitter is mounted closely adjacent to said audio receiver and includes a metal housing which acts as a radiating antenna, and wherein said hang-up support is devoid of movable parts and acts as a receiving antenna for signals emitted from said radiating antenna.
Claim 5
Dependent Claim
36 words
A telephone communication system as recited in claim 2 wherein said hang-up support is in the form of a hang-up hook, said hang-up hook being rigidly and insulatingly supported on a front panel of a housing.
Claim 6
Dependent Claim
56 words
A telephone communication system as recited in claim 4, said housing including a handset amplifier and a speaker amplifier, both energized by a common power source, a party line and a page line, movement of said handset to close proximity to said hang-up hook effecting disconnection of said handset amplifier from said party and page line.
Claim 7
Dependent Claim
38 words
A telephone communication system as recited in claim 5 wherein said proximity detector includes a phase-locked loop detector for detecting signals generated by said radiating antenna when said handset is moved to close proximity to said hang-up hook.
Claim 8
Dependent Claim
35 words
A telephone communication system as recited in claim 6 wherein said proximity detector includes an input buffer amplifier used as a voltage follower for for matching said hang-up hook antenna to a low impedance circuit.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-06-03 | 1983-12-03 | 1984-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-06-03 | 1987-12-03 | 1988-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-06-03 | 1991-12-03 | 1992-06-03 | $7700.00 | Window Closed / Lapsed |