Lock portion with piezo-electric actuator and anti-tamper circuit

• US 8,047,031 B2
• Filed: 12/27/2007
• Issued: 11/01/2011
• Est. Priority Date: 12/27/2007
• Status: Expired due to Fees

• Current Assignee: UTC Fire & Security Americas Corporation, Inc. (Carrier Global Corporation)
• Original Assignee: UTC Fire & Security Americas Corporation, Inc. (Carrier Global Corporation)
• Inventors: Bellamy, Dirk L., Seeley, Charles E.
• Primary Examiner(s): BARRETT, SUZANNE LALE DINO
• Application Number:
  US11/965,107
• Publication Number:
  US 20090165513A1
• Time in Patent Office: 1,405 Days
• Field of Search: 702/77, 702/782, 702/783, 702/787, 702/791, 702/83, 702/831
• US Class Current: 70/278.7
• CPC Class Codes: E05B 2047/0092 including means for preventing manipulation by an external magnetic field, e.g. preventing opening by using a strong magnet
• CPC Class Codes: E05B 2047/0093 including means for preventing manipulation by external shocks, blows or the like
• CPC Class Codes: E05B 47/0011 with piezoelectric actuators piezoelectric devices per se H10N30/00
• CPC Class Codes: E05B 47/0634 with a pivotally moveable blocking element
• CPC Class Codes: Y10T 70/7062 Electrical type [e.g., solenoid]
• CPC Class Codes: Y10T 70/7079 Key rotated [e.g., Eurocylinder]
• CPC Class Codes: Y10T 70/7102 And details of blocking system [e.g., linkage, latch, pawl, spring]
• CPC Class Codes: Y10T 70/7136 Key initiated actuation of device

Abstract

An electronic lock includes a rotatable core movable within an outer body. The rotatable core includes a piezo-electric actuator configured to move a tumbler blocking member into or out of interfering engagement with one or more tumblers. Tamper circuitry coupled with the piezo-electric actuator is configured to resist an externally induced acceleration of the electronic lock by shunting electrical power produced by an externally induced motion of the piezo-electric actuator back to the piezo-electric actuator.

Claims

1. An electronic lock, comprising:

a piezo-electric actuator positioned in a plug of a rotatable core, wherein the piezo-electric actuator has a first position and a second position and is configured to resist movement of a locking member during a non-normal unlocking operation of the electronic lock, wherein the locking member is at least partially positioned within a recess of the plug, and the piezo-electric actuator is in the first position when the electronic lock is locked and in the second position when the electronic lock is unlocked; and

tamper circuitry coupled with a connector of the piezo-electric actuator wherein the tamper circuitry is configured to resist an externally induced acceleration of the electronic lock by shunting electrical power produced by a resultant externally induced motion of the piezo-electric actuator back to the piezo-electric actuator such that the piezo-electric actuator bends toward the first position.

2. The electronic lock of claim 1, wherein the tamper circuitry is configured to collect a voltage created when the piezo-electric actuator moves in response to the externally induced acceleration.

3. The electronic lock of claim 2, wherein the tamper circuitry is further configured to shunt the collected voltage back into the piezo-electric actuator to resist a further movement of the piezo-electric actuator that could cause the electronic lock to unlock.

4. The electronic lock of claim 1, wherein the tamper circuitry a resistor circuit.

5. The electronic lock of claim 1, wherein the tamper circuitry is a resistor-inductor circuit.