GB2262075A

GB2262075A - Vehicle anti-theft device

Info

Publication number: GB2262075A
Application number: GB9125985A
Authority: GB
Inventors: Reginald John Williams
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-12-06
Filing date: 1991-12-06
Publication date: 1993-06-09
Also published as: GB9125985D0

Abstract

A vehicle anti-theft device 2 comprises a locking mechanism arranged to act on a vehicle handbrake. The locking mechanism includes a member 19 movable between first and second positions in which movement of the handbrake actuation linkage relative to the handbrake housing is permitted and inhibited respectively. Orientation of the movable member in the second position further causes the electrical ignition circuit 20, 22 of the vehicle to be broken. <IMAGE>

Description

Vehicle Anti-Theft Device This invention relates to a vehicle anti-theft device, and in particular to a device for locking the handbrake of a vehicle.

Locking mechanisms arranged to act on the "push-button" mechanism of automobile handbrakes are well known. Such mechanisms are disclosed for example in U.S.

patent 4858451 (which relates to a combination lock) and European patent specification 397588 (which relates to a key operated lock). Both of the devices disclosed provide a mechanical lock between the push-button handbrake actuation linkage (and the fixed outer casing of the handbrake. In order to breach the lock, a would be thief needs either to pick the lock, or physically destruct some component of the mechanism e.g. breaking the actuation linkage by hitting the push button with a hammer.

I have now devised an improved anti-theft device for locking a vehicle handbrake.

According to the invention, there is provided a vehicle anti-theft device comprising a locking mechanism arranged to act on a vehicle handbrake, said mechanism including a member which is movable from a first position in which operation of the handbrake is permitted, to a second position in which movement of the vehicle handbrake actuation linkage relative to the handbrake housing is substantially inhibited, and in which the electrical ignition circuit of the vehicle is broken.

The device therefore provides both a mechanical lock for the handbrake and also a selectively operated electrical ignition circuit breaker.

Returning the movable member to the first position permits relative movement of the actuation linkage and handbrake housing, and also restores the integrity of the vehicle ignition circuit, thereby enabling the handbrake to the operated and the vehicle started as normal.

Typically, the locking mechanism will comprise a key operated barrel lock.

Advantageously, the turning of the barrel lock between the first and second positions causes the movable member to move in the direction of the axis about which the lock turns.

Typically, the locking mechanism is provided with a screw threaded spigot which spigot engages with a complementary threaded bore provided in the movable member. As the locking mechanism turns under the action of the barrel lock, the threaded spigot turns in unison therewith causing the movable member to move along the threaded spigot between the first and second positions.

The movable member is preferably provided with an electrical contact portion arranged in the first position to be in conducting contact with two respective connecting terminals of the vehicle ignition circuit such that in the first position the vehicle ignition circuit is integral, and in the second position the vehicle ignition circuit is broken.

The movable member is preferably further provided with at least one formation arranged when the locking mechanism is in the second position to co-operatively engage with a complementary formation provided on the actuation rod of the handbrake.

Advantageously, the device is provided with illumination means arranged to be activated when the movable member is in the second position and deactivated when the member is in the first position. Typically, the illumination means is activated and deactivated by movement of the movable member.

The invention will now be further described in a specific embodiment, by way of example only, with reference to the accompanying drawings, in which Figure 1 is a plan view of the anti-theft device according to the invention in position on a vehicle handbrake; Figure 2 is a schematic side elevation of the device and handbrake shown in Figure 1; Figure 3 is a schematic detailed view of the device shown in Figures 1 and 2; and Figure 4 is a schematic plan view of the underside of the device shown in Figure 3.

Referring to the drawings, a vehicle handbrake 1 is fitted with an anti-theft device generally designated 2.

The device 2 comprises a key 3 operated barrel lock 4 fixed inside a housing 5 attached internally to the handbrake housing 6.

The handbrake actuation linkage 7 is connected to the actuation push-button 8, and comprises connected actuation rods 9, 10, 11 and an interconnecting plate 12.

Actuation rods 9 and 10 are connected by means of a split sleeve member 13 which is tightened around adjacent ends of respective actuation rods 9 and 10. Disposed within the sleeve is a stiff spring 14. In use, with the actuation linkage in its locked position, attempts to disable the anti-theft device by hammering the push-button 8 would merely cause the frictional engagement of sleeve member 13 with actuation rod 9 to be overcome and that rod to move in the direction of the lock against spring 14.

The interconnecting plate 12 passes through the housing 5 and is connected at opposed ends to respective ends of actuation rods 10 and 11. The plate 12 is provided with an elongate aperture 13 through which the threaded spigot 15 of the barrel lock 4 passes, and a further recess 16 the purpose of which is detailed below.

A movable member or block 19 is located within the housing 5 and has a bore 17 in threaded engagement with the threaded spigot 15. The upper surface of the block 19 is provided with a projecting lug 18 which in use is arranged in the locked position to cooperatively engage with the recess 16 in the plate 12. The lower surface of the block 19 is provided with a raised metallic strip 20 and ridge 21. In the locked position the strip 20 and ridge 21 are spaced from adjacent electrical contacts 22, 23 and sprung contact 24 respectively. In use, once the vehicle has been parked and the handbrake activated, the key 3 is turned causing the threaded spigot 15 of the barrel lock 4 to correspondingly rotate about its axis.In so doing, the actuation block 19 which is constrained within housing 5 moves upwardly on the threaded spigot 15 until the projecting lug 18 becomes engaged with the recess 16 in the plate 12. In this position (shown in Figure 3) the actuation linkage 7 is therefore locked and cannot move relative to the handbrake housing 6. As can be seen, in this position the conductive strip 20 is displaced from the electrical contacts 22, 23 and the vehicle ignition circuit 25 is therefore incomplete. Also in this position ridge 21 is not engaged with sprung contact 24 and therefore a circuit 28 is completed by resilient conductor members 26, 27 causing a battery operated bulb (not shown) to be illuminated. The bulb gives a visual indication that the anti-theft device is activated.

In order to "turn off" the anti-theft device, the key 3 is turned in the opposite sense causing the threaded spigot 15 to rotate in the opposite sense and the block 19 to move downwardly relative thereto causing lug 18 to disengage recess 16 in the plate 12. Also, conductive strip 20 contacts with electrical contacts 22, 23 completing the vehicle ignition circuit 25 such that the vehicle may be started. Finally, ridge 21 engages and depresses sprung contact 24 thereby depressing conductor member 27 causing circuit 28 to be broken and the bulb to be switched off.

Claims

CLAINIS:

l. A vehicle anti-theft device comprising a locking mechanism arranged to act on a vehicle handbrake, said mechanism including a member which is movable from a first position in which operation of the handbrake is permitted, to a second position in which movement of the vehicle handbrake actuation linkage relative to the handbrake housing is substantially inhibited, and in which the electrical ignition circuit of the vehicle is broken.
2. A vehicle anti-theft device according to claim 1, wherein returning the movable member to the first position permits relative movement of the actuation linkage and handbrake housing, and also restores the integrity of the vehicle ignition circuit.
3. A vehicle anti-theft device according to claim 1 or claim 2, wherein the locking mechanism is provided with a screw threaded spigot which spigot engages with a complementary threaded bore provided in the movable member, such that as the locking mechanism is actuated, the screw threaded spigot turns in unison therewith causing the movable member to move along the threaded spigot between the first and second positions.
A. A vehicle anti-theft device according to any preceding claim, wherein the movable member is provided with an electrical contact portion arranged in the first position to be in conducting contact with two respective connecting terminals of the vehicle ignition circuit such that in the first position the vehicle ignition circuit is integral, and in the second position the vehicle ignition circuit is broken.
5. A vehicle anti-theft device according to any preceding claim, wherein the movable member is provided with at least one formation arranged when the locking mechanism is in the second position to co-operatively engage with a complementary formation provided in the actuation linkage of the handbrake.
6. A vehicle anti-theft device according to any preceding claim, which further comprises illumination means arranged to be activated when the movable member is in the second position and deactivated when the member is in the first position.
7. A vehicle anti-theft device according to any preceding claim, wherein the locking mechanism comprises a key operated barrel lock, the turning of the barrel lock causing the movable member to move in the direction of the axis about which the lock turns.
8. A vehicle anti-theft device substantially as herein described with reference to the accompanying drawings.