Tamper switch activation without power

Patent metadata

Field	Value
Publication number	US-9777510-B2
Application number	US-201113040201-A
Country	US
Kind code	B2
Filing date	Mar 3, 2011
Priority date	Mar 3, 2011
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A tamper-detection device and system are disclosed. The tamper-detection device includes one or more components which enable the tamper-detection device to detect a state change, even in the absence of a power supply. A capacitor is provided in the tamper-detection device that, when shorted, discharges and induces a state change at a microcontroller of the tamper-detection device.

First claim

What is claimed is:

1. A tamper-detection device, comprising:
a tamper switch moveable between a first position and a second position, wherein the first position corresponds to a normal position of the tamper switch and the second position corresponds to a tamper-detected position;
a microcontroller connected to the tamper switch, wherein the microcontroller is configured to receive an input that indicates whether the tamper switch is in the first position or the second position;
a capacitor connected between the tamper switch and microcontroller, the capacitor being configured to discharge when no power is being provided to the microcontroller and the tamper switch moves from the first position to the second position; and
a second switch connected between the tamper switch and the microcontroller, wherein the second switch is configured to set a logical value at the microcontroller representing whether or not the tamper switch is installed.

2. The tamper-detection device of claim 1 , wherein the input is configured to be read by the microcontroller after power is reapplied to the microcontroller.

3. The tamper-detection device of claim 1 , wherein the microcontroller is further configured to activate a tamper function upon reading a discharged state of charge of the capacitor.

4. The tamper-detection device of claim 3 , wherein the microcontroller is further configured to disable at least some functionality of a device equipped with the tamper-detection device when the microcontroller recognizes activation of the tamper function.

5. The tamper-detection device of claim 4 , further comprising a display, wherein upon at least some functionality of the device equipped with the tamper-detection device being disabled, a message or signal relating to the disabled functionality is displayed on the display.

6. A safe equipped with the tamper-detection device of claim 1 .

7. A lock equipped with the tamper-detection device of claim 1 .

8. The tamper-detection device of claim 1 , wherein the capacitor is discharged providing the input to the microcontroller such that when power is later provided to the microcontroller, the microcontroller is capable of determining that the tamper switch was in the second position while no power was provided to the microcontroller.

9. The tamper-detection device of claim 1 , wherein the microcontroller is configured to disable a functionality of a device associated with the tamper-detection device, upon determining that the tamper switch was in the second position.

10. The tamper-detection device of claim 1 , wherein the microcontroller is configured to generate and issue a message upon determining that the tamper switch was in the second position.

11. The tamper-detection device of claim 1 , wherein the capacitor is further configured to maintain the input provided to the microcontroller when no power is being provided to the microcontroller as long as the capacitor has a charge and the tamper switch stays in the first position.

12. The tamper-detection device of claim 1 , wherein the capacitor is connected in parallel between the tamper switch and microcontroller.

13. A safe equipped with the tamper-detection device of claim 1 .

14. A lock equipped with the tamper-detection device of claim 1 .

15. The tamper-detection device of claim 1 , further comprising:
a signal generating device/circuit having time limited self-powering capability to generate and send a signal to the microcontroller reporting the tamper switch has changed states while no power is supplied to the microcontroller.

16. The tamper-detection device of claim 15 , wherein the signal generating device/circuit is a capacitor in series with a diode.

Assignees

• Moller Per Kristian
• Assa Abloy Ab

Inventors

• Moller Per Kristian

Classifications

• E05B47/00

  Operating or controlling locks or other fastening devices by electric or magnetic means (electric permutation locks E05B49/00) · CPC title

• E05B39/00 Primary

  Locks giving indication of {authorised} or unauthorised unlocking {(with key identification means E05B35/001; alarm locks E05B45/00)} · CPC title

• E05B65/0075

  for safes, strongrooms, vaults, fire-resisting cabinets or the like (safes, closures and fastenings therefor E05G) · CPC title

• E05G1/04

  Closure fasteners (locks E05B) · CPC title

• E05B2047/0058

  by batteries · CPC title