Patent US5272532A successfully refreshed from Google Patents.
US4490624A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Door control apparatus
Assignee: EFCO Manufacturing Co Pty Ltd
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Filing: 1983-05-31
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Granted: 1984-12-25
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Expires: 2003-05-31
Abstract
Abstract A fail safe mechanism for power operated doors comprises an auxiliary power supply, an electric motor, a self operating clutch to connect the motor to the door's normal drive assembly and a relay/timer circuit to energize the motor in the event of a mains failure to enable the motor to drive the door open.
Inventors
- 👤 Graham J. Luker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:15
CPC Classifications
E; E05; E05F; E05F15/00; E05F15/60; E05F15/603; E05F15/632; E05F15/643; E05Y; E05Y2201/00; E05Y2201/20; E05Y2201/23; E05Y2201/232; E05Y2400/00; E05Y2400/10; E05Y2400/30; E05Y2400/3013; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
95 words
Door operating means of the kind comprising an electric motor connectable to a mains power supply and a drive assembly operable by that motor to open and close a door characterised in that said operating means further comprise a second electric motor, an automatic clutch which when engaged, connects the second electric motor to enable it to operate the drive assembly to open the door, a second power supply, and means responsive to interruption of the mains power supply to energise the second electric motor from the second power supply and to engage the clutch.
Claim 2
Dependent Claim
95 words
Door operating means of the kind comprising an electric motor connectable to a mains power supply and a drive assembly operable by that motor to open and close a door characterised in that said operating means further comprise a second electric motor, an automatic clutch which when engaged, connects the second electric motor to enable it to operate the drive assembly to open the door, a second power supply, and means responsive to interruption of the mains power supply to energise the second electric motor from the second power supply and to engage the clutch.
Claim 3
Dependent Claim
45 words
Door operating means according to claim 1, wherein said clutch is a self-acting, one way clutch which automatically engages whenever the second motor is driven in a direction to open the door and automatically disengages when the second motor is driven in the opposite direction.
Claim 4
Dependent Claim
43 words
Door operating means according to claim 2, in which the means to energise the second electric motor include timer operated switches to de-energise the second electric motor at a predetermined time after each energisation thereof and then briefly to reverse the second motor.
Claim 5
Dependent Claim
25 words
Door operating means according to claim 1, wherein said second power supply comprises a battery and a battery charger energised by the mains power supply.
Claim 6
Dependent Claim
25 words
Door operating means according to claim 2 wherein said second power supply comprises a battery and a battery charger energised by the mains power supply.
Claim 7
Dependent Claim
25 words
Door operating means according to claim 3 wherein said second power supply comprises a battery and a battery charger energised by the mains power supply.
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) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |