GB2262266A - An anti-theft device - Google Patents

Abstract

The process is comprised of a photographic phase wherein there is used a film with appropriate dimensions in order to adapt the film to the side surface of a cylinder which is intended to embody the definitive printer form or printing plate, film wherein the effects are repeated and located in accordance with their number and arrangement, and which have to appear on said cylinder, the film being adapted to said cylinder, the cylinder being of copper and covered by a light-sensitive emulsion, whereafter an insulation of said assembly is achieved with a highly actinic light to finally subject the cylinder to a developping process. The second operative phase, subsequent to the photographic phase hereabove described, is a chemical phase wherein the cylinder is immersed in an iron perchloride solution or other solution capable of etching the uncovered parts of copper in order to obtain the corresponding low relief, the cylinder being subsequently and finally hardened by means of a chromium coating in a depositing bath.

Description

ANTI THEFT DEVICE The present invention relates to an anti-theft device for steerable vehicles and constitutes an important revolution in devices at present on sale for this purpose, since it completely immobilises the vehicle by means of a strong though very simple device.

As is well known, there are a large number of anti-theft devices at present on the market, the intention being to prevent a vehicle being moved from its position by anyone other than the owner.

Some existing devices, such as battery disconnectors, are designed so that when the starter motor is actuated the battery is prevented from delivering the current necessary for starting the vehicle, owing to the interposition of a switch which disconnects the two device, the switch normally being positioned in a secret place in the car known only to the user.

Since there are not many suitable hiding places in a car, professional thieves have gradually found them out, with the well-known result that it is easy to steal cars equipped with this kind of anti-theft device.

Other existing kinds of devices are based mainly on mechanical systems, mostly relying on the fixing of the steering wheel to some other part of the car by bars, chains or similar elements. In theory this appears safe, but no such system is invulnerable, and the thieves who steal cars have devised various methods of breaking the various anti-theft devices on the market and thus unlocking the steering wheel. Once the device is broken, it can be detached completely and the thieves can use a jump lead or the like to start the car and drive it away. Consequently the various devices on sale for this purpose are becoming increasingly vulnerable, as shown by the shocking statistics for car thefts at the moment.

The anti-theft device for motor vehicles on which the invention is based is designed to compete with the existing devices, by means of a device which is designed differently and which, by contrast, ensures total security against theft.

According to the present invention, there is provided a steering mechanism comprising: an input shaft; a hand operated steering member; and key operated lock means which is operable between a first condition in which rotation of the steering member is transmitted to the input shaft and a second condition in which rotation of the steering member is not transmitted to the input shaft.

In a preferred embodiment, the steering mechanism further comprises a first element which is fixed to the hand operated steering member; and a second element fixed to the input shaft, the said lock means being disposed between the first and second elements and being operable between the said first condition in which the first and second elements are rotationally interlocked so that rotation of the hand operated steering member is transmitted to the input shaft, and the second condition, in which the first and second elements can rotate relative to one another.

In an embodiment of the invention for use in preventing theft of a motor vehicle, the basic idea of the claimed device is that, when the first and second elements are not rotationally interconnected, the steering wheel turns freely around the steering column, so that even if the thief can start the vehicle, he cannot steer it under any circumstances, since the steering member does not perform its function of steering the wheels, preventing controlled motion of the vehicle by the thief.

According to a preferred embodiment, the antitheft device is inserted between the steering wheel and the steering column of a motor vehicle, between which an advantageously cylindrical first element is placed and is secured at one end to the base of the steering wheel. The other end of the first element is preferably hollow and receives a second element which may likewise be hollow and be secured to the steering column by a nut or other suitable means. The second element preferably has a lateral peripheral groove and a linear peripheral recess at a different level and occupying only a part of the periphery opposite a movable locking member which is situated in the first element and is actuated from the exterior, advantageously by a key, and is inserted into the grooves in the second element or is retracted into the first element, depending on the position of the key.

On the other side, the second element has a longitudinal extending groove corresponding to a projection of similar dimensions in the first element, which is fixed to the base of the steering member in order to limit the movement of the first element in a longitudinal direction.

Depending on whether the locking member, advantageously actuated by a key, is situated in the interior of the peripheral groove or in the linear groove formed in a sector of the second element, the steering member will either rotate loosely around the input shaft or will be rotationally interconnected with it.

The second of the aforementioned positions is the normal operating position and, with the locking member in this position, the vehicle can be driven in exactly the same way as a vehicle which is not fitted with a device as claimed in the present specification.

In the second case, i.e. when, advantageously by actuation by the key, the first element is released from the linear groove, the steering member is moved relative to the second element for the length permitted by the mechanical travel-limiter and again the key is actuated to insert the locking member into the peripheral groove, the steering member will rotate loosely, completely disengaged from the input shaft.

Consequently it is impossible for a would-be driver of a motor vehicle, for example, to steer the wheels by means of the steering wheel, and consequently the most that can be achieved by starting the vehicle is to move it in the direction last set by the owner when he left the vehicle. It is therefore certain that the vehicle cannot move far from where it was found and consequently it cannot be stolen under any circumstances.

Accordingly, the moment when an anti-theft device according to the invention has been installed in, for example, a motor vehicle, the vehicle will be drivable only by a person who inserts the key or the like into the device in order to align the device such that the steering wheel is rotationally interconnected with the steering column; until this occurs, the steering wheel will rotate loosely around the column without any possibility of transmitting the desired motion to the wheels.

For a better understanding of the present invention and to show how it may be carried into effect reference will now be made by way of example to the accompanying drawings, in which: Fig. 1 is a view in elevation, partly in section, of an anti-theft device for motor vehicles, the various components being shown separately; Fig. 2 is a section in plan view along line II-II of Fig. 1, showing the base of a steering wheel equipped with the device; Fig. 3 is another section in plan view along III III of Fig. 1, showing the inner piston (first element) of the device; and Figs. 4, 5 and 6 show three operating positions of the anti-theft device.

As shown in the drawings, the anti-theft device comprises a first element 1 joined by suitable fixing means (for example screws) 2 to the base of a steering member (steering wheel) 3. The element 1 has an inner cavity 4 into which is inserted the second element 5 of the device, which has a projection 6 in a region near its inner end, and a countersunk portion in a lateral region of its periphery 7 for receiving a locking member 8, a portion of which is of semi-circular crosssection, the locking member 8 being actuated by a key 9 from the exterior. At the level of the locking member 8 and in the region of the element 1 diametrically opposite to the member 8, a through orifice 10 is formed for inserting an advantageously screw-threaded cylindrical element 11 for limiting the position of the second element 5.

The aforementioned second element 5 has a substantially cylindrical shape, corresponding in diameter to the blind orifice 4 in element 1, and its innermost part is formed with a lateral recess 12 corresponding to the projections 6 of element 1, below which there is a horizontal groove 13 around the entire periphery, having a semicircular base and a size corresponding to the previously-described movable locking member 8.

Another tangentially extending groove 14 below the aforementioned peripheral groove 13 occupies only a part of the periphery, but likewise has a semicircular cross-section and is of the same depth as the first groove. Diametrically opposite to the groove 14 there is a cavity 15 which providing a passageway for the travel limiter 11 and guides its movement.

A sleeve 16 is suitably keyed to the bottom part of the second element 5 and is adapted to secure the steering wheel to the steering column 17 by conventional means. In other embodiments the connection can be made without an intermediate sleeve.

Figs. 4 to 6 will clearly show the operation of the anti-theft device for motor vehicles, both in the position where the car is in use and in the position where the car is locked.

Fig. 4 shows the arrangement of the device when the car is being driven normally.

Under these conditions, the semi-circular portion of the locking member 8 is locked inside the longitudinal groove 14 and the projection 6 on the first element 1 is inserted into the recess 12 formed in a complementary position in the second element 5, as a result of which the steering wheel and the first and second elements form a single assembly which rotates together with the steering column 17, and under these conditions the anti-theft device will be inoperative and the car will behave in exactly the same way as any other vehicle, not fitted with the device.

Fig. 5 shows what happens when, as a result of external action by key 9, the semi-circular portion of the locking member 8 is retracted into the countersunk part 7 in element 1 and, as a result, the outer element 1 is disengaged from the second element 5 so that the steering wheel can be pulled outwardly until the limiter 11 abuts the projection 18 forming the edge of the recess 12. In this position, shown in Fig. 6, the recess 12 is completely separate from the projection 6 and the locking member 8 is again rotated, so that it is situated inside the peripheral groove 13.

Under these conditions, if the steering wheel, is rotated in any direction its movement will be locked only to the outer element 1, which will rotate around the second element 5 without any engagement between them, and consequently the movement of the steering wheel cannot be transmitted to the steering shaft 17.

As a result a person trying to drive the vehicle without having the key for actuating the anti-theft device will not be able to move the wheels into any position other than that in which they were when the car was left locked.

As the foregoing description shows, it is completely impossible to lock the steering wheel to the steering column without possession of the actuating key, and consequently the anti-theft device is completely reliable and is a revolution as compared with the devices at present in commercial use for this purpose.

Claims (14)

1. A steering mechanism comprising: an input shaft; a hand operated steering member; and key operated lock means which is operable between a first condition in which rotation of the steering member is transmitted to the input shaft and a second condition in which rotation of the steering member is not transmitted to the input shaft.

2. A steering mechanism as claimed in claim 1 further comprising: a first element which is fixed to the hand operated steering member; and a second element fixed to the input shaft, the lock means being disposed between the first and second elements and being operable between the said first condition in which the first and second elements are rotationally interlocked so that rotation of the hand operated steering member is transmitted to the input shaft, and the second condition, in which the first and second elements can rotate relative to one another.

3. A steering mechanism as claimed in claim 2, in which the second element fits within the first element, the lock means comprising a locking member which is rotatable by means of a key to interconnect and disconnect the first and second elements.

4. A steering mechanism as claimed in claim 3, in which the locking member is situated within a bore formed in the first member, the locking member having a blocking portion which is movable upon rotation of the locking member between a disengaged position in which the blocking portion is housed within the first element, and an engaged position in which the blocking portion engages a groove in the second element.

5. A steering mechanism as claimed in claim 4, in which the second element is provided with two grooves, adapted to receive the blocking portion.

6. A steering mechanism as claimed in claim 5, in which the grooves are spaced from one another in the longitudinal direction, and in which the first and second elements are displaceable relatively to each other longitudinally, so that the blocking portion may be aligned with either of the grooves.

7. A steering mechanism as claimed in claim 5 or 6, in which one of the grooves is adapted to receive the blocking portion in a manner which rotationally interconnects the first and second elements.

8. A steering mechanism as claimed in claim 7, in which the other groove extends around the entire periphery of the second element, in a plane substantially at right angles to the longitudinal axis of the second element.

9. A steering mechanism as claimed in any one of the preceding claims, in which the end of the second element adjacent the steering member is adapted to cooperate with a surface of the first element to provide rotational interconnection between the first and second elements.

10. A steering mechanism as claimed in claim 9 when appendant to claim 7 or 8, in which the second element has cooperating means for engagement with the first element, the cooperating means being situated on the side of the second element diametrically opposite to the said one groove in the second element.

11. A steering mechanism as claimed in claim 10, in which the second element is provided with a longitudinally extending groove at substantially the same level as the said one groove and diametrically opposite thereto, the longitudinally extending groove providing a passageway for a projection which is fixed to the first element and limits the motion of the first element so as to prevent complete separation of the first and second elements.

12. A steering mechanism as claimed in claim 11, in which the longitudinally extending groove opens into the said other peripheral groove on one side of the said other groove, so that longitudinal movement of the projection is limited by the other side of the said other groove.

13. A steering mechanism as claimed in any one of the preceding claims in which the steering member is a steering wheel.

14. A steering mechanism substantially as described herein, with reference to and as shown in the accompanying drawings.