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US4745400A Expired / Lapsed US ⏱️ 0.0 years remaining

Alarm system

Assignee: Individual
•
Filing: 1986-08-12
•
Granted: 1988-05-17
•
Expires: 2006-08-12
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Abstract

Abstract An alarm system comprising a sensor which detects a human body in a fixed detection area and outputs signals, a delay timer circuit which outputs signals after passing a fixed delay time by turning on an alarm switch, a two input AND circuit in which output signals of the delay timer circuit and the sensor are entered, a latch circuit with a delay timer which outputs signals after passing a fixed delay time from when output signals of the two input AND circuit are entered and keeps the signals being outputed until entry of reset signals.

Inventors

  • 👤 Hirokazu Miura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:12
CPC Classifications
G; G08; G08B; G08B13/00

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 185 words
An alarm system comprising: a sensor positioned to detect the existence of a human body in a fixed detection area and outputs signals, a delay timer circuit which outputs signals after passing a fixed delay time by turning on an alarm switch, a two input AND circuit in which the signals outputted from said delay timer circuit and said sensor are entered, a latch circuit with a delay timer which outputs signals after passing the fixed delay time from a point of time when output signals of said two input AND circuit are entered, and keeps the signals until entry of reset signals, an alarm unit by which alarms are given by being operated by the output signals of said latch circuit, and wherein a retriggerable one-shot timer circuit, which outputs signals during a setup time from a point of time when the signals detected by the sensor are entered, is interposed between the sensor and the two input AND circuit so that the output signals of the sensor are entered in the two input AND circuit by way of the retriggerable one-shot timer circuit.
Claim 2
Dependent Claim 185 words
An alarm system comprising: a sensor positioned to detect the existence of a human body in a fixed detection area and outputs signals, a delay timer circuit which outputs signals after passing a fixed delay time by turning on an alarm switch, a two input AND circuit in which the signals outputted from said delay timer circuit and said sensor are entered, a latch circuit with a delay timer which outputs signals after passing the fixed delay time from a point of time when output signals of said two input AND circuit are entered, and keeps the signals until entry of reset signals, an alarm unit by which alarms are given by being operated by the output signals of said latch circuit, and wherein a retriggerable one-shot timer circuit, which outputs signals during a setup time from a point of time when the signals detected by the sensor are entered, is interposed between the sensor and the two input AND circuit so that the output signals of the sensor are entered in the two input AND circuit by way of the retriggerable one-shot timer circuit.

References Cited (Backward Citations)

US3449738A Cited
US3828338A Cited
US3858194A Cited
US3745550A Cited
US4122437A Cited
JPS5425700A Cited
US4485374A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-17 1991-11-16 1992-05-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-17 1995-11-16 1996-05-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-17 1999-11-16 2000-05-17 $7700.00 Window Closed / Lapsed

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