Patent US4920333A successfully refreshed from Google Patents.
US4920333A
Expired / Lapsed
US
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Internal pilferage alarm
Assignee: Individual
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Filing: 1988-05-26
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Granted: 1990-04-24
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Expires: 2008-05-26
Abstract
Abstract An alarm system for monitoring an entrance/exit from a premises is provided with a deadbolt switch, timing mechanism, alarm circuitry and an alarm indicator. The alarm system is activated when the deadbolt is unlocked. The alarm circuitry determines if the unlocking of the deadbolt was authorized or unauthorized. If the unlocking was unauthorized, the alarm indicator is activated. If the unlocking was authorized, the timing mechanism is activated. If the deadbolt is not relocked within the time period preset into the timing mechanism, the alarm indicator is activated. The timing mechanism may be reset by authorized persons to allow the deadbolt to remain open for additional time periods, one period at a time.
Inventors
- 👤 Robert Barr
- 👤 Joel A. Fletcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:13
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/02; G08B13/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
92 words
A method of activating an indication device, to indicate the unauthorized opening of a door, which may be temporarily deactivated for only a preset period of time, comprising the steps of determining whether opening of the door is authorized; activating the indication device if opening of the door is unauthorized; activating a timing clock set to run for a preselected period of time if opening of the door is authorized, and activating the indication device if the door is not closed within the time period set for the timing clock to run.
Claim 2
Independent Claim
92 words
A method of activating an indication device, to indicate the unauthorized opening of a door, which may be temporarily deactivated for only a preset period of time, comprising the steps of determining whether opening of the door is authorized; activating the indication device if opening of the door is unauthorized; activating a timing clock set to run for a preselected period of time if opening of the door is authorized, and activating the indication device if the door is not closed within the time period set for the timing clock to run.
Claim 3
Dependent Claim
20 words
The method according to claim 1, further comprising the step of resetting the timing clock when the door is closed.
Claim 4
Dependent Claim
31 words
The method according to claim 1, further comprising the steps of calculating the time remaining in the time period when the door is open, and displaying the time remaining for viewing.
Claim 5
Dependent Claim
28 words
The method according to claim 1, further comprising the step of operating the indication device from a battery back-up system when other sources of power are cut off.
Claim 6
Dependent Claim
32 words
The method according to claim 4, further comprising the steps of providing indication that the indication device has switched to battery power or that there is a malfunction of the indication device.
Claim 7
Dependent Claim
36 words
The method according to claim 1, further comprising the steps of determining whether the indication device is operating in proper working condition and indicating for observation if the indication device is not in proper working condition.
Claim 8
Dependent Claim
26 words
The method according to claim 1, further comprising the step of indicating the presence of a person at the outside of the door who requests entry.
Claim 9
Dependent Claim
95 words
An alarm system which indicates the unauthorized opening of a door, which can be deactivated for a only preset period of time, comprising: an alarm: means for determining whether opening of a door is authorized; means for activating the alarm if opening of the door is unauthorized; a timing clock set to run for a preselected time period; means for activating the timing clock and starting the time period running if opening of the door is authorized; and means for activating the alarm if the door is not closed before expiration of the time period.
Claim 10
Dependent Claim
95 words
An alarm system which indicates the unauthorized opening of a door, which can be deactivated for a only preset period of time, comprising: an alarm: means for determining whether opening of a door is authorized; means for activating the alarm if opening of the door is unauthorized; a timing clock set to run for a preselected time period; means for activating the timing clock and starting the time period running if opening of the door is authorized; and means for activating the alarm if the door is not closed before expiration of the time period.
Claim 11
Dependent Claim
18 words
The alarm system according to claim 8, wherein the timing clock is reset when the door is closed.
Claim 12
Dependent Claim
23 words
The alarm system according to claim 8, further comprising means for indicating time remaining in the time period when the door is open.
Claim 13
Dependent Claim
28 words
The alarm system according to claim 8, further comprising a battery back-up system which allows the alarm system to operate when other sources of power are cut off.
Claim 14
Dependent Claim
50 words
The alarm system according to claim 11, further comprising first and second indication means, first indication means for indicating that there is an unauthorized opening of the door, second indication means for indicating that the system has switched to battery power or that there is a malfunction of the alarm.
Claim 15
Dependent Claim
26 words
The alarm system according to claim 8 further comprising test means for allowing the internal components of the system to be tested for proper working condition.
Claim 16
Dependent Claim
27 words
The alarm system according to claim 8, further comprising indicating means for indicating the presence of a person at the outside of the door who requests entry.
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) | 1993-04-23 | 1993-10-23 | 1994-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-23 | 1997-10-23 | 1998-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-23 | 2001-10-23 | 2002-04-24 | $7700.00 | Window Closed / Lapsed |