Locking device having an integral alarm system

• US 3,993,987 A
• Filed: 03/03/1975
• Issued: 11/23/1976
• Est. Priority Date: 03/03/1975
• Status: Expired due to Term

• Current Assignee: Edward C. Stevens
• Original Assignee: Edward C. Stevens
• Inventors: Stevens, Edward C.
• Primary Examiner(s): Swann III, Glen R.
• Application Number:
  US05/554,964
• Time in Patent Office: 631 Days
• Field of Search: 340/283, 340/280, 340/274 R, 340/274 C, 340/63, 70/1, 70/35, 70/49, 70/416, 70/439, 200/61.67, 200/61.64, 200/DIG. 12
• US Class Current: 340/542
• CPC Class Codes: E05B 45/005 Chain-locks, cable-locks or padlocks with alarms
• CPC Class Codes: E05B 45/06 Electric alarm locks E05B45/005 takes precedence
• CPC Class Codes: Y10T 70/483 Flexible shackle

Abstract

A padlock includes a body and one or both ends of a shackle can be locked within the body by a lock bolt operated by a locking mechanism, such as a key-operated tumbler. The shackle contains an internal electrically conductive element which is connected in an electrical circuit with a battery and an alarm, both of which are located within the lock body. In addition, a series of insulated wires can be positioned along the inner wall of the body and are also connected in an electrical circuit. If the shackle or lock body is cut, or if the shackle is pried or separated from the lock body, the electrical circuit will be closed to actuate the alarm. The circuit is arranged so that either no power or minimum power is drawn from the battery unless the security of the padlock is violated.

Claims

1. A locking mechanism having an integral alarm system, including a lock body, shackle means having an end removably connected to the body, an electrically conductive element disposed within said shackle means, locking means disposed within the body and movable between a locked and released position, said locking means when in the locked position engaging the end of said shackle means to prevent removal of said end from the body and said locking means when in the released position permitting free removal of said end of the shackle means from said body, alarm means disposed within the body and connected in a normally non-conductive electrical circuit with said electrically conductive element and a source of electrical power, switch means connected in said circuit and having an open and a closed position, means responsive to moving the locking means to the released position for moving the switch means to the open position and reponsive to moving the locking means to the locked position for moving the switch means to the closed position, and means responsive to severing said element when said switch means is in the closed position for rendering said circuit conductive and actuating said alarm means.

2. The locking mechanism of claim 1, wherein said shackle means is a rigid shackle having an outer metal sheath, said element being insulated therefrom.

3. The locking mechanism of claim 1, wherein said alarm means is a horn.

4. The locking mechanism of claim 1, wherein said lock means is key actuated.

5. The locking mechanism of claim 1, and including means responsive to forceable removable of the shackle means from the lock body when the switch means is in the closed position for actuating said alarm means.

6. The locking mechanism of claim 1, and including a second electrically conductive element associated with the lock body and connected in said electrical circuit, severing of said second element by cutting the lock body when the switch means is in the closed position acting to render said circuit conductive to operate said alarm means.

7. A locking mechanism having an integral alarm system comprising a body, hollow electrically conductive shackle means having one end removably connected to the body, a first electrically conductive element disposed within the hollow interior of the shackle means and extending a substantial portion of the length of said shackle means, insulating means for spacing said element out of contact with said shackle means, a battery contained within the body, and alarm means disposed within the body, one end of said element connected in a normally non-conductive sensing circuit with the battery and the alarm means and said shackle means, the other end of said element being free of connection to said circuit, whereby the circuit is normally non-conductive, severing of said shackle means acting to bring said shackle means into electrical contact with said element to close said circuit and sound the alarm means.

8. The locking mechanism of claim 7, and including switch means connected in a second circuit with said battery and said alarm means and movable between an open and a closed position, connection of said shackle means to said body acting to move the switch means to the open position, and means operable as a consequence of forceable removal of the shackle means from the body for closing the switch means to actuate said alarm from the body for closing the switch means to actuate said alarm means.

9. The locking mechanism of claim 7, and including a second electrically conductive element disposed adjacent the inner surface of said body, second insulating means for spacing said second electrically conductive element out of contact with said body, one end of said second element being connected in a second electrical circuit with said battery and said alarm means and said body, the other end of said second element being free of connection with said second circuit whereby said second circuit is normally non-conductive, cutting of said lock body acting to move said second element into contact with said body to close said second circuit and sound said alarm means.

10. A locking mechanism having an integral alarm system, comprising a rigid electrically conductive structure, an electrically conductive element disposed adjacent said structure, insulating means for insulating the element from said structure, a battery, and alarm means, one end of said element being connected in a normally non-conductive sensing circuit with the battery and said alarm means and said structure, the other end of said element being free of connection to said circuit, whereby the circuit is normally non-conductive, deformation of said structure acting to move the structure into electrical contact with said element to close the circuit and sound said alarm means.

11. A locking mechanism having an integral alarm system, including a lock body, shackle means having an end removably connected to the body, an electrically conductive element disposed within the shackle means, locking means disposed within the body and movable between a locked and a released position, said locking means when in the locked position, engaging the end of said shackle means to prevent removal of said end from the body and said locking means when in the released position permiting free removal of said end of the shackle means from said body, alarm means disposed within the body, means responsive to severing said shackle means when the locking means is in the locked position for actuating said alarm means, a battery disposed within the body and connected to said alarm means, said body having an access opening for removal and insertion of said battery, a cover plate to enclose said access opening, and means associated with the shackle means for preventing removal of the cover plate when said end of the shackle means is engaged by said locking means.

12. The locking mechanism of claim 11, wherein said last named means comprises a projection on said shackle means and disposed to engage the outer surface of said cover plate.