WO2007015021A2 - Wrench for transmitting a clamping or loosening torque to an anti-theft screw device - Google Patents

Abstract

The invention relates to a wrench for transmitting a clamping or loosening torque to an anti-theft screw device (1) in particular for vehicle wheels, wherein said screw device comprises a head (11) provided with angularly and irregularly arranged peripheral and/ or front slots (13), whereas the wrench (2) is a bush-shaped provided with pins or fingers (23) which are embodied therein and positioned in the same order and used for interacting with the peripheral and/ or front slots (13) in such a way that a torque transmitting coupling is produced. The pins or fingers (23) are axially movably mounted in such a way that each of which is retracted in a receptacle (22) by a front push in order to be positioned for preventing any interaction with slots (13) of the head (11) if they are positioned in another ordering.

Description

KEY FOR TRANSMITTING A CLAMPING OR LOOSENING TORQUE TO A LOCKOUT DEVICE

The present invention relates to a key for the transmission of a tightening or loosening torque to an anti-theft screw device, in particular of vehicle wheels, of the type where the coupling is made through concordant impressions whose characteristics of shape, dimensions and layout are suitable for constituting a code.

Conventionally, the wheel of a motor vehicle is fixed by means of screws whose head, which allows the transmission of the tightening or loosening torque, is of hexagonal shape.

In order to prevent a third party from fraudulently removing the wheels, it is currently proposed that for each of the wheels, at least one of the screws has a head which requires a special key to be able to be maneuvered.

Numerous screw devices or the like provided with coding means are known, such as those described in documents GB 2.006.371, FR 2.359.730 and FR 2.567.215. These devices comprise on the one hand a screw whose head has either peripheral and / or facial notches arranged angularly irregularly, and on the other hand a socket-type key provided with pins or fingers arranged according to the same arrangement and intended to to cooperate with said notches in order to achieve the coupling capable of allowing the transfer of torque.

It is however possible for a malicious person wanting to force a screw as described above, to obtain a key of origin identical to that of said screw and having, obviously, a different code, and knowing that some random pieces or fingers can be at the good locations, to succeed by forcing to deform said key and to achieve the unscrewing of said screw.

It is indeed possible to find a key having two pins or fingers arranged at an angle identical to that between them two notches of a screw to force, while the other pins or fingers falling opposite the material, matent this one and contribute to the transmission of the couple.

The object of the present invention is to propose a key for the transmission of a tightening or loosening torque to an anti-theft screw device, in particular of vehicle wheels, which can not be used fraudulently. according to the manner previously described.

The key for the transmission of a tightening or loosening torque to an anti-theft screw device, in particular of vehicle wheels according to the invention, wherein said screw device comprises a head which has angularly arranged peripheral and / or facial notches. irregularly, while the key is of the socket type internally provided with pins or fingers arranged in the same arrangement and intended to cooperate with said peripheral and / or facial notches in order to perform the coupling capable of allowing the transmission of a torque, said key is essentially characterized in that said pins or fingers are movably mounted in axial displacement so that they can each during a front thrust retract into a housing to take a position preventing any cooperation with the notches of said head if they are arranged according to another arrangement.

The key according to the invention thus has a well defined footprint corresponding to a code, a footprint delimited by axially retractable mounted pins, so that if the screw does not have the corresponding impression, the engagement of said key on the latter causes the retraction of said fingers or pions, and therefore does not allow the meshing and thus the transmission of a couple.

It will be noted that documents US Pat. No. 5,193,420 and WO 97/14539 disclose keys for transmitting a torque to a screw or the like, comprising a multiplicity of pins, fingers or parallel needles which are retractable longitudinally and independently, so that by this retractability said key can adopt a profile complementary to that of said screw or the like to allow the transmission of a torque. Such a key can not be used as a key for anti-theft, it indeed has an object opposite to that of the present invention where the retractability of the pins or fingers is intended to prevent such adaptability.

The key according to the invention can not be forced on a screw, since the simple attempt to approach the key of an unsuitable screw causes the return of the pawn or fingers that are not exactly in front of the notches. However, one can still hijack the use of such a key. Indeed, if a single pin or finger can not allow to transmit the necessary torque, since there is no centering possible, it may happen that two pins or fingers are angularly arranged to allow such transmission.

Also, according to an advantageous additional feature of the key according to the invention, it comprises connecting means adapted to make all the pins or fingers integral displacement.

Thus, as soon as a single piece or finger does not engage in a notch, all the pieces or fingers go back at the same time in the key and it is no longer possible to transmit any torque. According to a particular embodiment of the key according to the invention, it is in the form of a socket having a cavity defined by a wall in the inner face of which are formed longitudinally sized housing and each formed to receive a finger or pin capable of moving axially, and adapted to cooperate with peripheral notches that includes the screw head.

According to an additional feature of the particular embodiment of the key according to the invention, it incorporates in the cavity an insert which is movable in axial displacement, and which the pins are hung.

According to another additional feature of the particular embodiment of the key according to the invention, the insert has a generally tubular shape and comprises a peripheral rim while the fingers or pins each laterally have a notch or the like adapted to cooperate with said edge so as to ensure a snap.

According to another additional feature of the particular embodiment of the key according to the invention, the pins or fingers are cylindrical in shape, the catch consisting of a peripheral groove.

According to another advantageous additional feature of the key according to the invention, the pins or fingers and the housings in which they are mounted mobile, are dimensioned so that said pins or fingers cooperate closely with said housings, in order to generate sufficient friction for prevent the reversibility of the retraction can be achieved by gravity.

Whatever the embodiment of the key according to the invention, this feature makes it even more difficult for malicious use of this key. It should be noted, however, that a possibility of return of the pawns or fingers by gravity or assisted through spring means can be provided.

The advantages and characteristics of the key according to the invention will emerge more clearly from the description which follows and which refers to the appended drawing, which represents a non-limiting embodiment thereof.

In the attached drawing:

- Figure 1 shows a schematic perspective view of an anti-theft screw device capable of being operated by a key according to the invention.

- Figure 2 shows a partial perspective view of a key according to the invention.

- Figure 3 shows a partial schematic sectional view along a median diametral plane of the same key.

- Figure 4 shows a perspective view and exploded part of the same key.

- Figure 5 shows a schematic sectional view along a median diametral plane of the same key and a portion of the anti-theft screw device.

Referring to Figure 1 can be seen an anti-theft screw device 1 to be operated by means of a key 1 according to the invention.

This anti-theft screw device 1 comprises a threaded body 10 surmounted by a head 11, which comprises a cylindrical drum 12 provided with peripheral notches 13 arranged angularly of irregularly, and intended to allow the transmission of a tightening torque or loosening.

Referring now to Figures 2 and 3, there can be seen a key 2 according to the invention, which in this case is in the form of an adaptable socket, for example, on a tool not shown, and which comprises in this effect of the opposite side to that open, a male footprint 24 intended to cooperate with a tool of conventional type.

The key 2 has on the open side a cavity 20 delimited by an inner wall 21 in which are formed housing 22, whose angular distribution is identical to that of the notches 13, and each in the form of a longitudinal groove of substantially semicircular section. circular.

With reference to FIGS. 4 and 5, it can be seen that the key 2 according to the invention comprises an insert 3 intended to be introduced into the cavity 20, which comprises a portion 30 of tubular shape which has at one end and externally a peripheral ridge 31, and at the other end an axial cylindrical stud 32 for insertion into a blind hole 25 formed in the key 2, in the bottom of the cavity 20. The dimensions of the cavity 20 and those of the insert 3 allow the latter to move axially, tightly and freely in the cavity 20, the sliding of the stud 32 in the blind hole 25 providing additional guidance.

Each housing 22 is intended to receive a finger 23 of generally cylindrical concordant shape and of a length less than that of the housing so as to be able to move axially.

The fingers 23 comprise a peripheral groove 26 of a width allowing to closely accommodate the peripheral rim 31 of the insert 3, so as to hang on, and thus bind all the fingers 23 to the displacement of the insert 3.

In the embodiment shown, the fingers 23 are fitted tightly into the housings 22 made between leather and flesh, so as not to be able to move freely by gravity, but only under the effect of an axial thrust, while that the insert 3 is itself retained in the cavity 20 through the fingers 23.

It will be understood that the insert 3 can thus move axially and take two extreme positions in and out. In the outward position, that shown in FIG. 4, the fingers 23 can cooperate with the notches 13 of the head 11 of the antitheft screw 1, whereas in the retracted position, where each of the fingers 23 is retracted in its housing 22, there is no cooperation with the notches 13.

In case of an attempt to use a key 2 on a screw 1 of different code, at least one of the fingers 23 not facing a notch 13 is pushed into its housing 22 and drives the other through of the insert 3, making the key unusable, and even more so if the fingers 23 can not automatically return to the extended position.

It should be noted that it is planned to limit the penetration of the head 11 into the cavity 20, in order to prevent the fingers 23 from cooperating with the notches 13 when the insert 3 abuts in the cavity 20, which is obtained by the cooperation abutting the end edge 27 of the sleeve 2 and the head 11 or more exactly of a peripheral shoulder 14 thereof.

Note further that the screw may not include a peripheral shoulder, and that in this case it may be provided that the end edge 27 of the sleeve 2 abuts directly on the object to be joined by screwing.

Claims

1) A key for the transmission of a tightening or loosening torque to an antitheft screw device (1), in particular of vehicle wheels, wherein said screw device (1) comprises a head (11) which has notches ( 13) peripheral and / or facial arranged angularly irregularly, while the key (2) is of the socket type internally provided with pins or fingers (23) arranged in the same arrangement and intended to cooperate with said peripheral and / or facial notches (13) to achieve the coupling capable of allowing the transmission of a torque, said key (2) is characterized in that said pins or fingers (23) are mounted movably in axial displacement so that they can each during a front thrust retract into a housing (22), to take a position preventing any cooperation with the notches (13) of said head (11) if they are arranged in another arrangement. 2) Key according to claim 1, characterized in that it comprises connecting means (3) adapted to make all the pins or fingers (23) integral in displacement. 3) Key according to claim 1, characterized in that it is in the form of a socket having a cavity (20) defined by a wall in the inner face (21) of which are formed longitudinal housing (22). dimensioned and each formed to receive a finger or pin (23) adapted to move axially, and adapted to cooperate with peripheral notches (13) that comprises the head (11) screw (1). 4) Key according to claim 3, characterized in that it incorporates in the cavity (20) an insert (3) which is movable therein. axial displacement, and to which the fingers or pins (23) are hung. 5) Key according to claim 4, characterized in that 1 'insert (3) has a generally tubular shape and comprises a peripheral flange (31) while the fingers or pins (23) each laterally have a notch or the like (26) adapted to cooperate with said flange (31) so as to ensure a snap. 6) Key according to claim 5, characterized in that the pins or fingers (23) are of cylindrical shape, the catch (26) consisting of a peripheral groove. 7) A key according to any one of the preceding claims, characterized in that the pins or fingers (23) and the housings (22) in which they are movably mounted, are dimensioned so that said pins or fingers (23) cooperate closely with said housings (22), in order to generate sufficient friction to prevent the reversibility of the retraction can be achieved by gravity.