US3815112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intrusion alarm
Assignee: Individual
•
Filing: 1972-08-09
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Granted: 1974-06-04
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Expires: 1992-08-09
Abstract
Abstract An improved intrusion alarm system is disclosed for protecting homes or businesses or other areas against entry by unauthorized persons. The system includes a central alarm device which is adapted for being coupled to a number of detecting stations positioned at doors or windows or other critical points. These separate detecting stations are coupled together by a single conductor protective electric loop. This loop contains one or more control stations which may be positioned at positions remote from the central alarm station and the control stations utilize the same single conductor protective loop to both test the loop and to turn the alarm system on and off. This multiple use of a single conductor, i.e. for protective, test, and off-on control is made possible by the use of light emitting diodes at the control stations which are operatively coupled into the single conductor protective loop for providing indicator and control functions.
Inventors
- 👤 D Kleber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:59
CPC Classifications
G; G08; G08B; G08B29/00; G08B29/12; G08B29/123; G08B13/00; G08B13/02; G08B13/08; G08B25/00; G08B25/01; G08B25/04; G08B25/045
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
102 words
In a detection system having one or more normally closed first switches and a current flow detector coupled in a series circuit and adapted for connection to a DC current source, the improvement comprising means for switching the current direction through said switches including means for changing the current value in said circuit comprising means for indicating the direction of current through said first switches and a second switch coupled across said indicating means, alarm means, and said switching means including means to connect said alarm to said current flow detector for one direction of current flow only through said first switches.
Claim 2
Dependent Claim
102 words
In a detection system having one or more normally closed first switches and a current flow detector coupled in a series circuit and adapted for connection to a DC current source, the improvement comprising means for switching the current direction through said switches including means for changing the current value in said circuit comprising means for indicating the direction of current through said first switches and a second switch coupled across said indicating means, alarm means, and said switching means including means to connect said alarm to said current flow detector for one direction of current flow only through said first switches.
Claim 3
Dependent Claim
39 words
The detection system as claimed in claim 1 in which said indicating means comprises a pair of light emitting diodes connected in parallel with each other with opposite polarities and with the parallel coupling connected serially in said circuit.
Claim 4
Dependent Claim
17 words
The detection system as claimed in claim 1 in which said switching means comprises a bi-stable relay.
Claim 5
Dependent Claim
24 words
The detection system as claimed in claim 1 in which said switching means comprises a bi-stable relay coupled to said circuit by amplifying means.
Claim 6
Dependent Claim
18 words
The detection system as claimed in claim 4 in which said amplifying means includes a time delay means.
Claim 7
Dependent Claim
27 words
The detection system as claimed in claim 1 in which said switches are connected to each other and to the DC current source by a single conductor.
Claim 8
Dependent Claim
130 words
In a detection system having one or more normally closed switch contacts and a current flow detector coupled in a series circuit adapted for connection to a DC current source, the improvement comprising means for switching the current direction in a portion of said circuit, said switching means being operated by a change in current value in said circuit and including means in said portion of said circuit to indicate the direction of current flow, alarm means, said switching means including means to connect said alarm to said detector for one direction of current flow only through said portion of said circuit and said indicator means comprising a pair of light emitting diodes connected in parallel with each other and having opposite polarities, and a switch connected across said diodes.
Claim 9
Dependent Claim
130 words
In a detection system having one or more normally closed switch contacts and a current flow detector coupled in a series circuit adapted for connection to a DC current source, the improvement comprising means for switching the current direction in a portion of said circuit, said switching means being operated by a change in current value in said circuit and including means in said portion of said circuit to indicate the direction of current flow, alarm means, said switching means including means to connect said alarm to said detector for one direction of current flow only through said portion of said circuit and said indicator means comprising a pair of light emitting diodes connected in parallel with each other and having opposite polarities, and a switch connected across said diodes.
Claim 10
Dependent Claim
106 words
In a detection system having one or more normally closed switch contacts and a current flow detector coupled in a series circuit and coupled to a DC current source, the improvement comprising the coupling to said current source including a pair of light emitting diodes coupled in parallel with each other and with opposite polarities, means for switching the polarity of the voltage across said diodes, said switching means including a switch to short said diodes to change the current value in said circuit, alarm means, and said switching means including means to connect said alarm to said detector for one voltage polarity across said diodes.
Claim 11
Dependent Claim
106 words
In a detection system having one or more normally closed switch contacts and a current flow detector coupled in a series circuit and coupled to a DC current source, the improvement comprising the coupling to said current source including a pair of light emitting diodes coupled in parallel with each other and with opposite polarities, means for switching the polarity of the voltage across said diodes, said switching means including a switch to short said diodes to change the current value in said circuit, alarm means, and said switching means including means to connect said alarm to said detector for one voltage polarity across said diodes.
Claim 12
Dependent Claim
119 words
In a detection system having one or more normally closed first switches and a current flow detector coupled in a series circuit and adapted for connection to a DC current source, the improvement comprising switching means for changing the current direction through said first switches including means for changing the current value in said series circuit, alarm means, said switching means including means to connect said alarm to said current flow detector for one direction of current flow only through said first switches, and said switching means further comprising a relay, the coil of said relay being coupled to a voltage source through second switch means, and said second switch means comprising a transistor controlled by said series circuit.
Claim 13
Dependent Claim
119 words
In a detection system having one or more normally closed first switches and a current flow detector coupled in a series circuit and adapted for connection to a DC current source, the improvement comprising switching means for changing the current direction through said first switches including means for changing the current value in said series circuit, alarm means, said switching means including means to connect said alarm to said current flow detector for one direction of current flow only through said first switches, and said switching means further comprising a relay, the coil of said relay being coupled to a voltage source through second switch means, and said second switch means comprising a transistor controlled by said series circuit.
References Cited (Backward Citations)
US3351934A
Cited
US3611362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |