Patent US4015256A successfully refreshed from Google Patents.
US4015256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic control unit for intrusion system
Assignee: Lanka Ltd
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Filing: 1975-10-02
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Granted: 1977-03-29
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Expires: 1995-10-02
Abstract
Abstract An electronic control center comprising part of an intrusion (burglar) alarm system, the control center being hermetically encapsulated in a mass of hard plastic (in lieu of the conventional steel cabinet enclosure) for purposes of economy and, significantly, to protect the control center from tampering and attack by an intruder. The control center is very small and presents a single multi-conductor cable directed way from the control center to the remainder of the alarm system including the sensors. The multi-conductor cable leading to the control unit includes a positive supply conductor, a negative supply conductor, four input conductors, one output conductor and one output monitor conductor for monitoring the continuity, during the day time, of the foil on the windows and the trap wiring (lacing) across skylights, air conditioning ducts etc. If any of the input conductors, the output conductors or the positive supply conductor is cut, while the system is activated, an alarm will occur. If the foil monitor output conductor is cut, the foil monitor buzzer will be disabled. In addition to the specific circuitry of the control center, light emitting diodes (LEDs) are imbedded in the protective mass of plastic and connected to the circuitry to respectively indicate the current status of the system per se and various areas of the system under surveillance. This is also important in troubleshooting and in determining whether the system is functioning correctly.
Inventors
- 👤 Arnold T. Pratt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:59
CPC Classifications
G; G08; G08B; G08B25/00; G08B25/14
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
415 words
An intrusion alarm system for surveillance of a restricted area comprising: a source of electrical power having a positive output voltage of relatively small magnitude; circuitry for delaying the enabling of surveillance of the restricted area which restricted area comprises an exit site, said circuitry comprising first switch means exposed, within the restricted area that actuates said delaying circuitry when manually operated and second switch means at said exit site which are open and closed by egress from said restricted area; said delaying circuitry further comprising at least first and second logic circuits each comprising integrated circuit components, said logic circuits comprising input and output means; the second switch means, when closed, communicating electrical power from said source to at least the input of the first logic circuit causing the input and output thereof to be high, the input and output of said first logic circuit becoming low when the switch means are opened; Rc delay circuit means comprising capacitor means connected between the source output voltage and the input to the second logic circuit and resistor means connected in series with the capacitor means between the input to the second logic circuit and ground, the RC circuit means having a time discharge constant exceeding the time for the system user to leave the restricted area via the exit sites; circuitry means for delaying the issuance of a low output when said circuitry means are implemented by the user immediately prior to the user leaving the restricted area via the exit site which temporarily communicates the source output voltage to the input of the second logic circuit whereby the input and output of said second logic circuit are high; means connecting the output of the first and second logic circuits to alarm means; means blocking the communication of a low output of the first logic circuit to the alarm means; whereby opening of the second switch means by the user leaving the restricted area via the exit site as mentioned will cause the first logic circuit to be low at its input and output which low is blocked by said blocking means and said RC delay circuit means will retain the second logic circuit in a high state for a period of time equal to the time discharge constant during which time said second switch means will again be closed, the first logic circuit becoming high at its input and output and said high being communicating to said alarm means whereby no alarm is issued.
Claim 2
Dependent Claim
415 words
An intrusion alarm system for surveillance of a restricted area comprising: a source of electrical power having a positive output voltage of relatively small magnitude; circuitry for delaying the enabling of surveillance of the restricted area which restricted area comprises an exit site, said circuitry comprising first switch means exposed, within the restricted area that actuates said delaying circuitry when manually operated and second switch means at said exit site which are open and closed by egress from said restricted area; said delaying circuitry further comprising at least first and second logic circuits each comprising integrated circuit components, said logic circuits comprising input and output means; the second switch means, when closed, communicating electrical power from said source to at least the input of the first logic circuit causing the input and output thereof to be high, the input and output of said first logic circuit becoming low when the switch means are opened; Rc delay circuit means comprising capacitor means connected between the source output voltage and the input to the second logic circuit and resistor means connected in series with the capacitor means between the input to the second logic circuit and ground, the RC circuit means having a time discharge constant exceeding the time for the system user to leave the restricted area via the exit sites; circuitry means for delaying the issuance of a low output when said circuitry means are implemented by the user immediately prior to the user leaving the restricted area via the exit site which temporarily communicates the source output voltage to the input of the second logic circuit whereby the input and output of said second logic circuit are high; means connecting the output of the first and second logic circuits to alarm means; means blocking the communication of a low output of the first logic circuit to the alarm means; whereby opening of the second switch means by the user leaving the restricted area via the exit site as mentioned will cause the first logic circuit to be low at its input and output which low is blocked by said blocking means and said RC delay circuit means will retain the second logic circuit in a high state for a period of time equal to the time discharge constant during which time said second switch means will again be closed, the first logic circuit becoming high at its input and output and said high being communicating to said alarm means whereby no alarm is issued.
Claim 3
Dependent Claim
334 words
An intrusion alarm system for surveillance of a restricted area comprising: a source of electrical power having a positive output voltage of relatively small magnitude; alarm means; first switch means disabling and enabling the alarm means; circuitry for delaying the issuance of an alarm by the alarm means when the first switch means is in the enabling position after a person ingresses into a restricted area through an entrance site, said circuitry comprising second switch means at said entrance site being opened and closed by a person ingressing to said restricted area; said circuitry further comprising at least first and second logic circuits each comprising integrated circuit component, said logic comprising input and output means; the second switch means, when closed, communicating electrical power from said source to at least the input means to the first logic circuit causing the voltage at the input means and output means thereof to be high, the voltage at the input and output means of said first logic circuit becoming low when the second switch means are opened; resistor means interposed between the output means of the first logic circuit and the input means to the second logic circuit; first capacitor means of relatively large charge capacity interposed between the source and the output means of the first logic circuit; second capacitor means of relatively small charge capacity serially connected to said resistor means and first capacitor means and connected to the input means of the second logic circuit; whereby when the voltage at the input and output means of the first logic circuit is caused to be low by opening of the second switch means the voltage at the input and output means of the second logic circuit is maintained high by a sustained discharge for a predetermined period of time of the first capacitor means to the second capacitor means during which predetermined time the person ingressing into the restricted area may actuate the first switch means to disable the alarm means without issuing an alarm.
Claim 4
Dependent Claim
334 words
An intrusion alarm system for surveillance of a restricted area comprising: a source of electrical power having a positive output voltage of relatively small magnitude; alarm means; first switch means disabling and enabling the alarm means; circuitry for delaying the issuance of an alarm by the alarm means when the first switch means is in the enabling position after a person ingresses into a restricted area through an entrance site, said circuitry comprising second switch means at said entrance site being opened and closed by a person ingressing to said restricted area; said circuitry further comprising at least first and second logic circuits each comprising integrated circuit component, said logic comprising input and output means; the second switch means, when closed, communicating electrical power from said source to at least the input means to the first logic circuit causing the voltage at the input means and output means thereof to be high, the voltage at the input and output means of said first logic circuit becoming low when the second switch means are opened; resistor means interposed between the output means of the first logic circuit and the input means to the second logic circuit; first capacitor means of relatively large charge capacity interposed between the source and the output means of the first logic circuit; second capacitor means of relatively small charge capacity serially connected to said resistor means and first capacitor means and connected to the input means of the second logic circuit; whereby when the voltage at the input and output means of the first logic circuit is caused to be low by opening of the second switch means the voltage at the input and output means of the second logic circuit is maintained high by a sustained discharge for a predetermined period of time of the first capacitor means to the second capacitor means during which predetermined time the person ingressing into the restricted area may actuate the first switch means to disable the alarm means without issuing an alarm.
Claim 5
Dependent Claim
137 words
An alarm system comprising: sensor means for the surveillance of a restricted area including means for issuing an alarm when the restricted area is invaded; a control center comprising means controlling said sensor means and said alarm means, said controlling means comprising circuitry imbedded in a mass of essentially tamper proof hard synthetic resinous material without any other physical enclosure; said circuitry comprising delay means to allow authorized personnel to enter and exit said restricted area without issuing an alarm and a plurality of interrelated logic means interposed serially between ground and alarm output means, all of which are in a common electrical state when enabled and no invasion of the restricted area has occurred, all of the last-mentioned logic means changing state and thereby causing an alarm to issue when invasion of the restricted area occurs.
Claim 6
Dependent Claim
137 words
An alarm system comprising: sensor means for the surveillance of a restricted area including means for issuing an alarm when the restricted area is invaded; a control center comprising means controlling said sensor means and said alarm means, said controlling means comprising circuitry imbedded in a mass of essentially tamper proof hard synthetic resinous material without any other physical enclosure; said circuitry comprising delay means to allow authorized personnel to enter and exit said restricted area without issuing an alarm and a plurality of interrelated logic means interposed serially between ground and alarm output means, all of which are in a common electrical state when enabled and no invasion of the restricted area has occurred, all of the last-mentioned logic means changing state and thereby causing an alarm to issue when invasion of the restricted area occurs.
Claim 7
Dependent Claim
20 words
An alarm system according to claim 3 wherein said common electrical state is a relatively low or zero voltage level.
Claim 8
Dependent Claim
63 words
An alarm system according to claim 3 wherein the control center is electrically connected to the sensor means and the alarm means by a cable comprising a plurality of conductors respectively connected to said circuitry and the logic means thereof, the severance of the cable or said conductors causing substantially all of said logic means to change state and an alarm to issue.
Claim 9
Dependent Claim
56 words
An alarm system according to claim 3 further comprising memory means comprising a plurality of lamps responsively interconnected to said circuitry said circuitry being imbedded in said mass of essentially tamper proof hard synthetic resinous material, said lamps being substantially imbedded in said material with a portion of each exposed at the face of said material.
Claim 10
Dependent Claim
230 words
An intrusion alarm system comprising: an alarm output circuit whereby an alarm issues when the circuit output voltage is low; transistor means connected at the collector thereof to the alarm output and to ground at the emitter of said transistor means; normally open reset switch means connected to an input voltage from an electrical power supply and by which said input voltage is momentarily communicated to the base of the transistor means; key switch means connected between the input voltage and the alarm output whereby the input voltage is caused to be communicated to said output when the key switch means are closed; whereby (a) when the reset switch means are first momentarily closed followed by opening of the key switch means, the system is enabled without issuance of an alarm by said reset switch means placing substantially all of the system logic circuitry in a high state, (b) momentary closing of the reset switch means after the system is enabled causes the output to be placed at ground potential by said closing changing the logic state from high to low causing an alarm to issue, and (c) prior to the system being enabled, operating of the key switch means followed by closing of the reset switch means will place that output at ground potential by also changing the logic state from high to low causing an alarm to issue.
Claim 11
Dependent Claim
230 words
An intrusion alarm system comprising: an alarm output circuit whereby an alarm issues when the circuit output voltage is low; transistor means connected at the collector thereof to the alarm output and to ground at the emitter of said transistor means; normally open reset switch means connected to an input voltage from an electrical power supply and by which said input voltage is momentarily communicated to the base of the transistor means; key switch means connected between the input voltage and the alarm output whereby the input voltage is caused to be communicated to said output when the key switch means are closed; whereby (a) when the reset switch means are first momentarily closed followed by opening of the key switch means, the system is enabled without issuance of an alarm by said reset switch means placing substantially all of the system logic circuitry in a high state, (b) momentary closing of the reset switch means after the system is enabled causes the output to be placed at ground potential by said closing changing the logic state from high to low causing an alarm to issue, and (c) prior to the system being enabled, operating of the key switch means followed by closing of the reset switch means will place that output at ground potential by also changing the logic state from high to low causing an alarm to issue.
Claim 12
Dependent Claim
249 words
An intrusion alarm system comprising: input means for an electrical power supply; first circuitry interposed between input power and ground comprising logic means the state of which changes when detecting intrusion into a first restricted area under surveillance; second circuitry interposed between input power and ground comprising logic means the state of which changes when detecting intrusion into a second restricted area under surveillance; alarm output means connected to the first and second circuitry causing an alarm to issue when at least one restricted area is invaded and the state of said logic thereof has been caused to change; each said circuitry comprising memory means to which said change of state is communicated and means retaining said communicated change of state whereby the system user may subsequently be informed of the intrusion, and whereby the system may be tested by the user to insure proper function and detection; at least some of said first and second circuitry being imbedded in a mass of hard synthetic resinous material and wherein said memory means comprise a plurality of lamp means connected to each circuitry, each circuitry being imbedded in a unitary, mass of hard synthetic resinous material, said lamps being substantially imbedded therein but retaining a portion thereof exposed at the face of said mass whereby intrusion into at least one restricted area will cause the lamp means associated therewith to be illuminated, and further comprising means causing said illumination to be maintained for subsequent visual inspection by the system user.
Claim 13
Dependent Claim
249 words
An intrusion alarm system comprising: input means for an electrical power supply; first circuitry interposed between input power and ground comprising logic means the state of which changes when detecting intrusion into a first restricted area under surveillance; second circuitry interposed between input power and ground comprising logic means the state of which changes when detecting intrusion into a second restricted area under surveillance; alarm output means connected to the first and second circuitry causing an alarm to issue when at least one restricted area is invaded and the state of said logic thereof has been caused to change; each said circuitry comprising memory means to which said change of state is communicated and means retaining said communicated change of state whereby the system user may subsequently be informed of the intrusion, and whereby the system may be tested by the user to insure proper function and detection; at least some of said first and second circuitry being imbedded in a mass of hard synthetic resinous material and wherein said memory means comprise a plurality of lamp means connected to each circuitry, each circuitry being imbedded in a unitary, mass of hard synthetic resinous material, said lamps being substantially imbedded therein but retaining a portion thereof exposed at the face of said mass whereby intrusion into at least one restricted area will cause the lamp means associated therewith to be illuminated, and further comprising means causing said illumination to be maintained for subsequent visual inspection by the system user.
References Cited (Backward Citations)
US3648268A
Cited
US3858192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-28 | 1980-09-27 | 1981-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-28 | 1984-09-27 | 1985-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-28 | 1988-09-27 | 1989-03-29 | $7700.00 | Window Closed / Lapsed |