GB2173247A

GB2173247A - Anti-theft steering lock device for motor vehicles

Info

Publication number: GB2173247A
Application number: GB08606527A
Authority: GB
Inventors: Mario Turatti
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-04-02
Filing date: 1986-03-17
Publication date: 1986-10-08
Also published as: GB8606527D0; IT1183789B; YU46786A; ES293300Y; IT8567323A1; FR2579537A1; JPS61232947A; FR2579537B1; DE3610831A1; ES293300U; IT8567323A0; GB2173247B

Abstract

An anti-theft steering lock device for motor vehicles has a cam rotor (26) controlled by a cylinder (12) lock for operating a latch (54) movable perpendicular to the axis (B) of the lock by an intermediate transmission member. The transmission member is formed by a shaft (56) which is rotatable about an axis (A) perpendicular to the axis of rotation (B) of the cam rotor (26) and to the direction of movement of the latch (54), and which is associated with first (38) and second safety devices for preventing the accidental closure of the latch (54) when the key is inserted in the lock. <IMAGE>

Description

SPECIFICATION Anti-theft steering lock device for motor vehicles The present invention relates in general to antitheft steering lock devices for motor vehicles.

More particularly, the invention concerns a steering lock device of the type including a housing containing a cylinder lock movable axially in the body as a result of the insertion of a key and arranged to rotate a cam rotor which operates a latch, movable in a direction perpendicular to the axis of the lock and under the action of resilient biassing means, between a withdrawn rest position and an advanced operative position for locking the steering shaft of a vehicle against rotation, and in which an intermediate transmission member is provided for the operation of the latch by the cam rotor, which extends in an appendage of the body perpendicular to the axis of the lock and from which the latch projects transversely, and in which safety means are also provided for preventing the accidental movement of the latch from the withdrawn position to the advanced position when the key is inserted in the lock.

Anti-theft steering lock devices of this type are known, for example, from German Patents Nos. 26 51 496, 27 11 701, 28 25 873 and 32 27 256. In all the devices described and illustrated in these patents, the intermediate transmission member is constituted by a rocker arm articulated about a pivot pin within the appendage of the body. In order to allow the necessary pivoting movement of the rocker arm, the appendage of the housing has a considerable width, which makes the device bulky overall. Moreover, the use of a rocker arm as the transmission member hetween the cam and the latch involves considerable constructional complications, and also complicates the safety means for preventing the accidental closure of the latch.

The object of the present invention is to avoid these disadvantages and to provide an anti-theft steering lock device for motor vehicles of the type defined at the beginning which is less bulky and simpler and cheaper to make than known steering locks of the same type.

According to the invention this object is achieved by virtue of the fact that the intermediate transmission member is constituted by a shaft rotatable about an axis perpendicular to the axis of rotation of the cam rotor and to the direction of movement of the latch, the shaft having a control part at one end cooperating with the cam rotor and a drive part at its other end cooperating with the latch to move it from the advanced position to the withdrawn position and vice versa as a result of the rotation of the shaft.

The use of a rotatable shaft instead of a pivotable rocker arm allows the transverse dimensions of the lateral appendage of the housing to be reduced, at the same time making the steering lock stronger and simpler overall.

According to the invention, the safety means include a body rotatable with the cam rotor and movable axially therewith together with the cylinder lock, the body also being movable axially relative to the cam rotor between a lowered position and a raised position against the action of resilient biassing means; the body having an abutment head disposed angularly upstream of the cam rotor relative to the sense of rotation therecf corresponding to the movement of the latch from the advanced position to the withdrawn position and arranged to cooperate with the control part of the shaft to prevent its rotation corresponding to the movement of the latch from the withdrawn position to the advanced position until the key is withdrawn from the lock.

According to another aspect of the invention, the safety means further include a stop bar slidably housed in the appendage of the housing parallel to the said shaft, the bar being movable, by means of the cam rotor and against the action of a return spring, between a withdrawn rest position corresponding to the advanced position of the latch and an advanced stop position, corresponding to the withdrawn position of the latch, in which it projects into a complementary notch in the latch.

The invention will now be described in detail with reference to the appended drawings, provided purely by way of non-limiting example, in which: Figure 1 is a schematic view of an anti-theft steering lock device for mctor vehicles, according to the invention in partial axial section, Figure 2 is a section taken on the line ll-ll of Figure 1, Figure 3 is a section taken on the line Ill-Ill of Figure 2, Figure 4 is a cross-section taken on the line IV-IV of Figure 2, Figure 5 is a view similar to Figure 2 of the steering lock device in a different operative condition, Figure 6 is a sectional view taken on the line VI-VI of Figure 5, Figure 7 is a view similar to Figure 3 with the device in a different operative condition, Figure 8 is a perspective view of part of the device, and Figure 9 is an exploded view of Figure 8.

Figure 1 is a schematic general illustration of a anti-theft steering lock device usable for locking the steering shaft (not illustrated) of a motor vehicle.

The device comprises essentially a housing 10 having a main part 10a and a lateral subsi diary part 10b whose axis A is perpendicular to the axis B of the main part 10a.

Within the main part 10a is a cylinder lock 12 including a stator 14 and a rotor or rotatable cylinder 16 cooperating in known manner with the stator 14.

The rotor 16 is slidable axially relative to the part lOa of the body 10, or relative to the stator 14, as a result of the insertion of an operating key in a key seat 18 into the lower part of which projects a stop member 20.

When the key is inserted, the rotor 16 may be lowered against the action of a return spring 22 until the stop 20, which is pushed radially outwardly by the key, engages a complementary abutment 24 of the stator 14. The removal of the key from the rotatable cylinder 16 allows it to return to the raised position under the action of the spring 22.

The rotatable cylinder 16 rotates a camshaped rotor, generally indicated 26, for operating the steering lock unit of the device. An axial shaft 28 extends from the cam-shaped rotor 26 and controls and ignition switch, not illustrated, housed in the base of the housing 10.

As best seen in Figures 2, 5, 8 and 9, the cam rotor 26 has a lower substantially semicylindrical portion 30 defined on the side facing the shaft 28 by an axial face 32 and by a fiat end face 34, which, as will be seen below, constitute the actual cam element for operating the steering lock.

As clearly seen in Figures 2 and 5, the portion 30 is defined laterally by a surface 36 shaped to constitute a further cam the function of which will be clarified below.

A body 38 is coupled to the rotor 26 in a position facing the semi-cylindrical portion 30.

The body 38 is generally T-shaped, comprising a semi-cylindrical stem 40 with an axial projection 42 slidably coupled in a complementary groove 44 of the shaft 28, and a semi-cylindrical head 46 facing the base surface 26a of the rotor 26 left free by the portion 30. Between the head 38 and this surface 26a is a helical compression spring 48 which tends to retain the body 38 in the lowered axial position illustrated in Figures 3, 7 and 8.

The body 38 is able to move axially from this lowered position into a raised position, compressing the spring 48 in the manner clarified below. A radial pin 50 carried by the shaft 28 and slidably engaged in an axial slot 52 in the body 38 is provided for guiding this movement of the body 38. In the lowered position of the body 38, the pin 50 is disposed at the end of the slot 52 facing the surface 26a.

It is thus clear that the body 38 is rotatable together with the rotor 26 and is movable axially with the rotor 26 as long as the rotatable cylinder 16 is lowered by means of the key against the action of the spring 22, and that this body 38 is also movable axially relative to the rotor 26 against the action of the spring 48.

A parallelapipedal member 54 is inserted in the end of the appendage 10b opposite the wall 1 0a of the housing 10 and constitutes the latch of the device, intended to cooperate with the steering shaft (not illustrated) of a vehicle. The latch 54 is slidable in a direction C (Figures 2 and 5) perpendicular to the axes A and B.

The latch 54 is operated in the manner explained below by the cam rotor 26 through an intermediate transmission member constituted, according to the invention, by a shaft 56 located within the lateral part 1 0b of the housing 10 and rotatable about the axis A. The shaft 56 has a tang 58 at one end which projects into the part 10a and carries a tapered radial projection 60 arranged to cooperate with the cam rotor 26 and the head 46 of the body 38, in the manner clarified below.

The opposite end of the shaft 56 carries an eccentric axial pin 62 which at one end projects into a transverse slot 64 of the latch 54 and at the opposite end projects into a recess 66 in the shaft 56. An arm 68a of a return spring 68 reacts against the part of the pin 62 projecting into the recess 66, the other arm 68b of the spring reacting against the part 10b of the housing 10. The spring 68 biasses the shaft 56 to rotate in the sense corresponding to advance of the latch 54, that is, in the sense indicated by the arrow F in Figure 6.

A stop bar or slide, indicated 70, is slidable in a seat 72 in the part 10b of the housing 10, parallel to the axis A of the shaft 56. The bar 70 is movable, as explained below, between a withdrawn rest position illustrated in Figure 2, in which it does not interfere with the latch 54, and an advanced working position in which it projects into a complementary notch 74 in the latch 54. The movement from the withdrawn position to the advanced position occurs by virtue of the cooperation between the bar 70 and the lateral cam surface 36 of the part 30 of the rotor 26, while its return from the advanced position to the withdrawn position is achieved by means of a helical compression spring 76 surrounding the bar 70.

The operation of the steering lock device according to the invention will now be described starting from the condition illustrated in Figures 1 to 4 and 8. This condition corresponds to the stop position of the rotatable cylinder 16 of the lock 12 and of the ignition switch controlled thereby.

In the stop position, the rotatable cylinder 16 and the cam rotor 26 are in the raised position under the action of the spring 22, the radial projection 60 of the shaft 56 is disposed beneath the head 46 of the body 38, and the latch 54 is located in the advanced locking position with the bar 70 kept in the withdrawn position by the spring 76.

On insertion of the key in the seat 18 of the rotatable cylinder 16 and the lowering of this together with the cam rotor 26 to allow the movement of the ignition switch to its operative positions, simultaneous lowering of the body 38 driven by the pin 50 occurs. The lowering of the body 38 is blocked, however, by the radial projection 60 of the shaft 56 whereby the surface 26a approaches the head 46 of the body 38 to compress the spring 48.

At this point, rotation of the key in the sense indicated by the arrow H in Figures 2 and 8, to the operative positions of the switch (running, starting), causes the frontal surface 32 of the part 30 of the rotor 26 to approach the projection 60 of the shaft 56.

By virtue of the tapered form of this projection 60, the abutment against the surface 32 causes the shaft 56 to rotate in the sense indicated by the arrow G in Figure 8. On the one hand this rotation causes the withdrawal of the latch 54 by means of the eccentric pin 62 to the withdrawn position of Figures 5 and 6, thus freeing the steering shaft, and on the other hand disengages the body 38 from the radial projection 60 which then bears on the surface 34 of the part 30 under the action of the spring 68. Consequently, the body 38, acted upon by the spring 48, moves into the starting position illustrated in Figures 3 and 8.

At the end of the withdrawal of the latch 54, the lateral cam 36 of the part 30 causes the bar 70 to move outwardly against the action of the spring 76 to achieve the engagement of the latch 54 in the notch 74.

Consequently, the latch 54 is kept in the withdrawn position both by the bearing of the projection 60 on the surface 34 and the engagement of the bar 70 in the notch 74.

This situation remains in all the operative positions to which the switch of the device can be brought by rotation of the rotatable cylinder 16, as well as when the cylinder 16 is returned to the stop position. In this situation, however, the rotation of the shaft 56 corresponding to withdrawal of the latch 54 is prevented by the radial projection 60 bearing against the edge of the head 46 of the body 38, in the manner illustrated in Figure 7.

If one starts from this position and withdraws the key from the rotatable cylinder 16, the stop 20 allows the rotor 26 to move into the raised position under the action of the spring 22, with the consequent driving of the body 38 in the same direction. This manoeuvre thus frees the radial projection 60, allowing the shaft 56 to rotate in the sense of the arrow F (Figure 6) under the action of the spring 68 and locate the latch 54 in the advanced position in which it locks the steering shaft (Figures 1-4 and 8). Simultaneously, the lateral cam surface 36 of the part 30 frees the bar 70 to allow it to return to the withdrawn position under the action of the spring 76.

It will be clear from the above that the steering lock device according to the invention is particularly simple and safe in operation, particularly with regard to the safety function of avoiding accidental movement of the latch 54 from the withdrawn position to the advanced position; this function is in fact carried out in two ways by two separate and independent members (the radial projection 60 and the bar 70).

Furthermore, the device has a small bulk and is simpler and cheaper to manufacture than conventional devices of the same type, by virtue of the use of the rotatable shaft 56.

A further advantage offered by the use of the rotatable shaft 56 lies in the possibility of varying the angle between the axes A and B, that is between the portions 10b and 10a of the housing 10 and the respective components housed therein, thus giving the device greater flexibility of application.

Naturally, the principle of the invention remaining the same, the constructional details and forms of embodiment may be varied widely with respect to that described and illustrated, without thereby departing from the scope of the present invention.

Claims

1. Anti-theft steering lock device for motor vehicles, including a housing containing a cylinder lock movable axially in the body as a result of the insertion of a key and arranged to rotate a cam rotor which operates a latch, movable in a direction perpendicular to the axis of the lock and under the action of resilient biassing means, between a withdrawn rest position and an advanced operative position for locking the steering shaft of a vehicle against rotation, and in which an intermediate transmission member is provided for the operation of the latch by the cam rotor, which extends in an appendage of the body perpendicular to the axis of the lock and from which the latch projects transversely, and in which safety means are also provided for preventing the accidental movement of the latch from the withdrawn position to the advanced position when the key is inserted in the lock, wherein the intermediate transmission member is constituted by a shaft rotatable about an axis perpendicular to the axis of rotation of the cam rotor and to the direction of movement of the latch, the shaft having a control part at one end cooperating with the cam rotor and a drive part at its other end cooperating with the latch to move it from the advanced position to the withdrawn position and vice versa as a result of the rotation of the shaft.

2. Device according to Claim 1, in which the control part and the drive part of the shaft are formed respectively by a radial projection and an eccentric axial pin engaged in a transverse slot in the latch.

3. Device according to Claim 2, in which the resilient biassing means for the latch are constituted by a spring acting on the eccentric pin and biassing the shaft to rotate it towards the advanced position of the latch.

4. Device according to any one of the preceding claims, in which the safety means include a body rotatable with the cam rotor and movable axially therewith together with the cylinder lock, the body also being movable axially relative to the cam rotor between a lowered position and a raised position against the action of resilient biassing means, the body having an abutment head disposed angularly upstream of the active part of the cam rotor relative to the sense of rotation thereof corresponding to the movement of the latch from the advanced position to the withdrawn position and arranged to cooperate with the control part of the shaft to prevent its rotation corresponding to the movement of the latch from the withdrawn position to the advanced position until the key is withdrawn from the lock.

5. Device according to Claim 4, in which the body is connected to the cam rotor by a sliding coupling including a radial pin engaged in an axial slot in the body.

6. Device according to Claim 4 or Claim 5, in which the safety means further include a stop bar slidably housed in the appendage of the housing parallel to the shaft, the bar being movable, by means of the cam rotor and against the action of the return spring, between a withdrawn rest position corresponding to the advanced position of the latch and an advanced stop position, corresponding to the withdrawn position of the latch, in which it projects into a complementary notch in the latch.

7. Anti-theft steering lock device substantially as herein described with reference to, and as shown in, the accompanying drawings.