Claims
- 1. A method of operating a motor actuated electric lock comprising:
- (a) operating the motor in a first direction;
- (b) monitoring energy consumed by the motor;
- (c) if the energy is abnormal, operating the motor in a second direction opposite the first; and
- (d) repeating at least step (a).
- 2. The method of claim 1 in which step (b) includes monitoring current drawn by the motor.
- 3. The method of claim 1 which includes alternately attempting to operate the motor in the first direction, and then in the second direction, N times, where N is at least two, and discontinuing said attempts after N times if abnormal energy consumption persists.
- 4. The method of claim 3 in which N is at least five.
- 5. The method of claim 3 in which the lock is in a first state before the method commences, and returning the lock to the first state if said attempts are discontinued.
- 6. The method of claim 1 in which the motor is operated in the second direction for about 255 milliseconds.
- 7. A method of freeing a jam in a motor-operated lock, comprising:
- detecting the jam in the lock based on energy consumed by the motor; and
- freeing the jam by reversing a direction in which the motor is operating at least twice.
- 8. The method of claim 7 in which the detecting includes monitoring current drawn by the motor.
- 9. The method of claim 7 in which the detecting includes detecting if a current drawn by the motor is at least six times greater than a normal operating current.
- 10. A method of freeing a jam in a motor-operated lock, comprising:
- detecting the jam in the lock; and
- shaking the lock by alternatingly operating the motor in opposite directions.
- 11. The method of claim 10 in which the lock is in a first state before the method commences, further comprising returning the lock to the first state if the jam is not shaken free after a predetermined number of attempts.
Parent Case Info
This application is a continuation-in-part of application Ser. No. 08/873,054, filed Jun. 11, 1997, which is a continuation-in-part of U.S. patent application Ser. No. 08/746,322, filed Nov. 11, 1996, which claims priority from U.S. provisional application No. 60/009,920, filed Jan. 12, 1996. This application is also a continuation-in-part of copending application 09/067,353, filed Apr. 27, 1998. The foregoing applications are incorporated herein by reference.
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Related Publications (1)
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Number |
Date |
Country |
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067353 |
Apr 1998 |
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Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
873054 |
Jun 1997 |
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Parent |
746322 |
Nov 1996 |
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