US4825196A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal transmission circuit of fire/security protection system
Assignee: Nohmi Bosai Ltd
•
Filing: 1987-09-02
•
Granted: 1989-04-25
•
Expires: 2007-09-02
Abstract
Abstract A signal transmission circuit provided with a control panel or a terminal device of a fire/security protection system is arranged so as to transmit a signal for the control panel or terminal device to a signal line. The signal transmission circuit includes: a signal transmission which is enabled when transmitting a signal under the control of a signal processing portion; a signal detector for detecting the signal transmitted from the signal transmitter to the signal line; a timer which is set when the signal is transmitted and is reset by the detection output from the signal detector, and a signal transmission controller for turning off the signal transmitter when the time count output of the timer exists during a predetermined time interval.
Inventors
- 👤 Toshikazu Morita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:53
CPC Classifications
G; G08; G08B; G08B25/00; G08B25/01; G08B25/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
128 words
A signal transmission circuit which is provided in a control panel or a terminal device of a fire/security protection system and transmits a signal from a signal processing portion to a signal line, and which is equipped with a signal transmission means which is set to a state ready for signal transmission under control of the signal processing portion when transmission is desired, a signal detection means which detects the signal transmitted from the signal transmission means to the signal line, a timer means which is triggered at the time of signal transmission and reset by output of the signal detection means, and a signal transmission control means which sets the signal transmission means to the OFF state when a given time of the timer means is reached.
Claim 2
Dependent Claim
128 words
A signal transmission circuit which is provided in a control panel or a terminal device of a fire/security protection system and transmits a signal from a signal processing portion to a signal line, and which is equipped with a signal transmission means which is set to a state ready for signal transmission under control of the signal processing portion when transmission is desired, a signal detection means which detects the signal transmitted from the signal transmission means to the signal line, a timer means which is triggered at the time of signal transmission and reset by output of the signal detection means, and a signal transmission control means which sets the signal transmission means to the OFF state when a given time of the timer means is reached.
Claim 3
Dependent Claim
84 words
A signal transmission circuit of a fire/security protection system as set forth in claim (1) wherein the signal transmission means is equipped with a signal transmission portion and a memory part which stores the signal sent to the signal transmission portion from the signal processing portion, and the signal detection means is equipped with a signal detection portion and a discrimination portion which generates a detection signal when the signal detected by the signal detection portion matches the signal stored in the memory portion.
Claim 4
Dependent Claim
35 words
A signal transmission circuit of a fire/security protection system as set forth in claim (1) wherein the timer means is triggered when the signal transmission means is set to a state ready for signal transmission.
Claim 5
Dependent Claim
36 words
A signal transmission circuit of a fire/security protection system as set forth in claim (1) wherein the timer means is triggered when the signal is transmitted from the signal processing part to the signal transmission means.
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) | 1992-04-24 | 1992-10-24 | 1993-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-24 | 1996-10-24 | 1997-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-24 | 2000-10-24 | 2001-04-25 | $7700.00 | Window Closed / Lapsed |