Antitheft alarm system for automobiles

• US 3,891,967 A
• Filed: 10/15/1973
• Issued: 06/24/1975
• Est. Priority Date: 04/20/1971
• Status: Expired due to Term

• Current Assignee: Clifton R. Betts
• Original Assignee: Clifton R. Betts
• Inventors: Betts, Clifton R.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US05/406,147
• Time in Patent Office: 617 Days
• Field of Search: 340/63,64,65,56 307/1LS,1BP,1AT 337/1 180/114
• US Class Current: 340/428
• CPC Class Codes: B60R 25/1003 Alarm systems characterised by arm or disarm features

Abstract

An alarm system for automotive vehicles to protect the same against unauthorized entry into any of the various compartments protected by the system including the passenger compartment, trunk compartment, and engine compartment. The system utilizes insofar as possible the existing electrical system of such vehicle including the horn, lights, and door switches thereof; and it includes a key-operated master switch accessible from the exterior of the vehicle, a relay having an energizing coil and multiple sets of contacts, and a circuit connecting the master switch with the relay and connecting the system with the closure switches and electrically operated devices of the vehicle which are to be used to attract attention to any attempt an unauthorized entry into the compartments thereof. The system when once energized continues in operation either indefinitely irrespective of whether the compartment switch initiating operation of the system remains open or closed or, in certain forms of the invention, for a definite or predetermined period resetting itself automatically for a subsequent cycle of operation if the compartment switch initiating operation of the system is deactuated as by the compartment door being closed. Also, the system may be used to energize the vehicle lights for predetermined periods to light the way for one leaving the vehicle in the absence of environmental light.

Claims

1. An alarm system for automotive vehicles and the like having an electrical system, also having at least one electrically operated device usable when energized to attract attention to such vehicle to protect the same against unauthorized entry into a compartment thereof, futher having a closure member for an access opening into such compartment, and still further having a compartment switch arranged with the closure member so as to be actuated by opening thereof, comprising:

a circuit having a pluality of conductors connectable with such electrical system, device, and compartment switch;

a master switch connected in said circuit and movable between open and closed positions for selectively conditioning said alarm system for operation;

an alarm-actuating mechanism connected in said circuit so as to maintain the same normally in an inoperative condition and such device de-energized and to effect operation of said circuit and energization of such device whenever said master switch has conditioned said alarm system for operation and such compartment switch is actuated;

said alarm-actuating mechanism and said circuit being provided with operation-maintenance means effective to maintain said circuit in an operative condition and such device energized following deactivation of such compartment switch;

whereby such device and compartment switch are usuable in an ordinary manner but when said master switch is closed, opening such closure member will actuate the compartment switch to energize said alarm-actuating mechanism and such device and to maintain the energized state of the latter even after deactuation of the compartment switch;

condition-sampling means arranged in said circuit in operative connection with said Alarm-actuating mechanism and operation-maintenance means thereof to test the condition of said circuit as determined by the condition of such compartment switch so as to return said circuit to an inoperative condition and de-energize such device after a predetermined time interval if such compartment switch is deactuated and set said alarm system for a subsequent cycle of operation or to permit said circuit to remain in the operative condition thereof with such device energized if such compartment switch remains actuated; and

light switch means connectable with the exterior lights of such vehicle so as to energize the same and connected in circuit with said condition-sampling means, said light switch means being manually operable so as to energize such vehicle lights when desired and being returned to an inoperative state automatically by said condition-sampling means following expiration of a predetermined time interval.

2. The alarm system of claim 1 in which condition-sampling means includes a thermal-sensitive switch connected in series with said light switch means and operative to interrupt the circuit therethrough in response to a temperature elevation occasioned by the flow of current through said thermal-sensitive switch for a predetermined time interval.

3. The alarm system of claim 1 in which said alarm-actuating mechanism includes a relay having an energizing coil and two sets of contacts the normal conditions of which are changed by energization of said coil, said master switch being connected in series with one of said sets of contacts in a self-holding configuration with said coil and defining the aforesaid operation-maintenance means;

and said alarm-actuating mechanism further including a second relay having an energizing coil connected with the other of said set of contacts provided by said first relay so as to energize the coil of said second relay whenever said other set of contacts is closed, said second relay having a normally open set of contacts connectable with the electrical system of such vehicle and with such device for energizing the latter through a separate power circuit whenever each of said relays is energized.

4. The alarm system of claim 3 in which said condition-sampling means includes a thermal-sensitive switch connected with said operation-maintenance means so as to periodically interrupt the circuit therethrough, whereby said circuit will be returned to the inoperative condition thereof if such compartment switch is then deactuated.

5. An alarm system in combination with an automotive vehicle or the like having a compartment, a closure therefor and a voltage supply providing electric power for said alarm system, comprising:

a condition sampling circuit having a ground connected to said voltage supply, said condition sampling circuit containing a compartment switch arranged to complete the circuit when such closure is in the open position thereof and open circuiting the condition sampling circuit when such closure is in the closed position;

an alarm activation circuit having an electrically operated device usable when energized to attract attention to such vehicle for protection of the same against unauthorized entry into such compartment;

a first activation means for energizing said alarm activation circuit in response to completion of said condition sampling circuit;

an alarm maintaining circuit substantially in parallel with said compartment switch when actuated;

a second activation means for actuating said alarm maintaining circuit in response to completion of said condition sampling circuit; and

a time delay switch in said alarm maintaining circuit providing a completed circuit for a set period of time after which said delay switch opens thereby deactuating said alarm maintaining circuit, whereby said electrically operated device is activated upon opening of the compartment closure and is maintained in the activated state for a set period of time irrespective of the condition of the compartment switch and thEreafter said device is deactivated unless said compartment switch is closed.

6. The alarm system of claim 5 further comprising a direct alarm circuit having a ground directly connected to said voltage supply through said electrically operated device;

a third activation means in said alarm activation circuit for actuating said direct alarm circuit in response to energization of said alarm activation circuit.

7. The alarm system of claim 6 wherein said direct alarm circuit contains a plurality of electrically operated devices in parallel.

8. The alarm system of claim 6 wherein said first and second activation means comprise an integral relay having an energizing coil and two sets of contacts corresponding to the first and second means, said contacts being normally open and closed by energization of said coil;

said third activation means is a relay having an energizing coil and a set of contacts operating similarly to the other relay;

said time delay switch is a thermal sensitive switch having a thermal element and a set of contacts normally closed until said thermal element reaches a set temperature occasioned by flow of current therethrough, and thereafter said contacts open and remain so until said thermal element cools to another set temperature;

said alarm system further comprising a master switch in said condition sampling circuit for deactivating such alarm system whenever desired.

9. The alarm system of claim 6 wherein said device comprises the headlights of such vehicle;

said alarm system further comprising a timed lighting circuit coupled to said alarm activation circuit means substantially in parallel relation with said third activation means and a manual switch operable when closed to actuate said condition-sampling means whereby said lighting circuit is actuated and the headlights are turned on, and said timed light circuit further including said time delay switch cooperatively sharing the same with said alarm maintaining circuit for breaking the timed lighting circuit after a set period of time and thereby automatically turning off said headlights.

10. The alarm system of claim 9 further comprising another electrically operated device usable when energized to attract attention to such vehicle for protection of the same against unauthorized entry into such compartment and situated in said alarm activation circuit for operation whenever said circuit is energized, whereby said device operates whenever such compartment closure is open and may continue for a set period of time even after such compartment closure is closed, and the same functions irrespective to the condition of said electrically operated device.