Tamper indicating bolt

• US 6,791,465 B2
• Filed: 07/11/2001
• Issued: 09/14/2004
• Est. Priority Date: 07/11/2000
• Status: Active Grant

• Current Assignee: National Technology & Engineering Solutions Of Sandia LLC (Honeywell International Inc.)
• Original Assignee: Boris P. Barkanov, Sergei V. Blagin
• Inventors: Barkanov, Boris P., Blagin, Sergei V.
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): NGUYEN, HUNG T
• Application Number:
  US09/903,844
• Publication Number:
  US 20020044063A1
• Time in Patent Office: 1,161 Days
• Field of Search: 340/665, 340/652, 340/541, 340/542, 340/426, 340/539.1, 411/2, 411/14, 737/61, 737/63
• US Class Current: 340/665
• CPC Class Codes: F16B 41/005 Measures against unauthorised operation of bolts, nuts or pins F16B23/0007, F16B23/0061, F16B23/0069, F16B23/0076 and F16B31/02 take precedence; locks, keys E05B; for valves, taps or cocks F16K35/00; for pipe-joints with swivel-nuts F16L19/005

Abstract

A tamper-indicating fastener has a cylindrical body with threads extending from one end along a portion of the body, and a tamper indicating having a transducer for converting physical properties of the body into electronic data; electronics for recording the electronic data; and means for communicating the recorded information to a remote location from said fastener. The electronics includes a capacitor that varies as a function of force applied by the fastener, and non-volatile memory for recording instances when the capacitance varies, providing an indication of unauthorized access.

Claims

1. A tamper indicating fastener having a cylindrical body with threads extending from one end along a portion of the body, and a tamper indicating portion extending from an other end of said body, said tamper indicating portion comprising:

a transducer for converting physical properties of the body into electronic data;

electronic means for processing the electronic data; and

means for communicating the processed data to a remote location from said fastener.

2. The tamper indicating fastener of claim 1 wherein said transducer comprises a capacitor for measuring strain in the fastener.

3. The tamper indicating fastener of claim 2 wherein said capacitor comprises a dielectric disk having spaced surfaces, one surface being covered with metal, the other surface facing a first surface of a movable metal plate, said plate having an opposed second surface, wherein the distance between said other surface of said disk and said first surface of said plate being a function of the strain in the fastener.

4. The tamper indicating fastener of claim 3 wherein said body extends along an axis and has a hole extending through said body parallel to said axis from said tamper indicating portion towards said threads;

and

a rod within said hole, said rod being fastened to said body only at one end within said hole, an other end of said rod being fastened to said opposed second surface of said movable plate.

5. The tamper indicating fastener of claim 2 wherein said electronic means comprises a microcontroller and non-volatile memory, said electronic means storing data indicative of a reduction in strain on said fastener in said non-volatile memory.

6. The tamper indicating fastener of claim 5 wherein said electronic means further stores encoded data indicative of the identity of said fastener.

7. The tamper indicating fastener of claim 5 further comprising a battery in said tamper indicating portion for powering said electronic means.

8. The tamper indicating fastener of claim 7 wherein said microprocessor includes a clock, and said microprocessor records the date and time of a reduction in strain in said non-volatile memory.

9. The tamper indicating fastener of claim 1 wherein said cylindrical body defines a threaded portion of said fastener extending along an axis and said tamper indicating portion forms a head having a larger diameter than said threaded portion;

said head having a base of larger diameter than said threaded portion centered on said axis at one end of said threaded portion;

a side wall extending away from said threads, and a cover enclosing a volume also defined by said side wall and said base.

10. The tamper indicating fastener of claim 9 wherein said means for communicating comprises a first inductive coil within said side wall, said first inductive coil being electrically connected to said electronic means.

11. The tamper indicating fastener of claim 10 further comprising a communicating device comprising:

a second inductive coil having an inner diameter larger than the outer diameter of said first inductive coil;

a housing containing said second inductive coil, wherein said second inductive coil is proximate said first inductive coil when said housing is placed over said head of said fastener; and

means for communicating electrical data between said second inductive coil and a data processing device.

12. The tamper indicating fastener of claim 11 wherein said electronic means comprises a microcontroller and non-volatile memory, said electronic means storing data indicative of a reduction in strain on said fastener in said non-volatile memory.

13. The tamper indicating fastener of claim 12 wherein said electronic means further stores encoded data indicative of the identity of said fastener.

14. The tamper indicating fastener of claim 13 further comprising a battery in said tamper indicating portion for powering said electronic means.

15. The tamper indicating fastener of claim 14 wherein said microprocessor includes a clock, and said microprocessor records the date and time of a reduction in strain in said non-volatile memory.