DE69201888T2 - Anti-theft switch for motor vehicles. - Google Patents

Description

The present invention relates to an electric anti-theft rotary switch for motor vehicles, which can be operated at the user's choice by means of the ignition key, according to the preamble of claim 1 and as described in US-A-2 520 363. It usually comprises a housing with a flat shape, as can also be seen from FR-A-2 019 972, FR-A-2 373 138 and DE-U-7 218 524.

All these designs do not meet the various requirements of the manufacturers, which in certain cases require that the switch be equipped either with a second switch for inserting the ignition key, for example to trigger an alarm if the driver has left the ignition key in the steering lock when closing the vehicle door, or with additional contacts, for example to control the brake circuit.

To solve this problem, it is being considered to develop a new anti-theft switch that is specific to each application, but this is detrimental to standardization.

The purpose of the present invention is to create a new anti-theft switch in a simple and economical way in standard design, which can be equipped with one or more additional devices as required.

According to the invention, the problem is solved according to the characterizing part of claim 1.

Thanks to the invention, it is possible, without increasing the installation space and with a minimum of parts, to produce a robust standard housing and, if desired, to easily incorporate, for example, a second switch by means of the recess left by the fixed contacts and the over-thicknesses, which advantageously takes place before the housing is assembled to the body.

The over-thicknesses and the passages not only allow the formation of a recess that interacts with the protruding fixed contacts, but also, if desired, the stable fastening of the fixed contacts by inserting the tongues.

It is therefore possible to produce a housing of any thickness by moulding, with the option of fixing or not fixing certain fixed contacts, such as the contacts intended for testing the braking circuit if required. In all cases, these contacts are made stable thanks to their two tongues spaced apart from one another.

According to a feature of the invention, at least one of the over-thicknesses has a limited height in order to accommodate an additional fixed contact to which a contact blade is attached, which belongs to a second switch for inserting the ignition key.

The bottom of the housing can advantageously be provided with a projecting stepped tongue, for retaining a plunger belonging to said second switch, and with projecting guide means, such as slide rails or guide pins, for guiding said plunger, which is made possible by the aforementioned recess.

It is noted that the protruding arrangement of at least some of the fixed contacts creates the conditions for a good contact area for the moving contacts, while also prolonging the life of the switch.

The fixed contacts together with the moving contacts form a sliding contact device, so that metal particles can become detached during the service life of the switch.

Thanks to the invention, these metal particles fall into the bottom of the housing, thus preventing the formation of creepage distances between the various contacts.

It should also be noted that the movable contacts and the sliding piece cannot become dirty when moving from one fixed contact to another thanks to the raised areas. The switch therefore functions perfectly.

The following description illustrates the invention with reference to the accompanying drawings, in which:

- Figure 1 shows a top view of the anti-theft switch according to the invention.

- Figures 2 to 4 show sectional views without the body of the switch along the lines A-A, B-B and C-C of Figure 1 respectively.

- Figure 5 shows a plan view showing the interior of the housing of the anti-theft switch according to the invention.

- Figure 6 shows a partial sectional view along the line D of Figure 5.

The electric anti-theft rotary switch of Figures 1 to 6 is connected to the steering lock for the ignition key of the motor vehicle. The steering lock enables the steering column of the vehicle to be locked and the anti-theft switch to be operated via the ignition key at the user's discretion, in particular to start the vehicle.

This anti-theft switch comprises the following parts: a body 1 made of non-conductive material, a return spring 2, locking means 3, 4, 56, a spring latch 6, on which a spring 5 acts, a backstop 7, a rotor 8 made of non-conductive material, an axially movable conductive slide 9, on which three springs 10 act, a housing 11 made of non-conductive material, a plunger 13 made of non-conductive material, on which a spring 12 acts, a conductive contact pin 15, on which a spring 14 acts, a conductive contact blade 17, fixed conductive contacts 16 and 19 to 24 and an additional fixed conductive contact 18 for the power supply to a second switch.

A non-conductive material is understood here to mean an electrically non-conductive material and a conductive material is understood to mean an electrically conductive material.

Parts 1, 8, 11, 13 are made of plastic and parts 9 and 15 to 24 are made of metal, with parts 15 to 24 being made of copper.

The fixed contacts firmly connected to the housing 11 16 and 19 to 24 are designed to interact by friction with the movable contacts 61 located on the slider 9 which is driven in rotation by the rotor 8 which in turn can be actuated at the user's discretion by means of the ignition key.

In detail, the electric anti-theft rotary switch comprises a body 1 which is assembled with a housing 11 made of an electrically non-conductive material such as plastic to form a holder to be attached to the steering lock, this housing being hollow, open and provided with a base 42 in which passages 46 and over-thicknesses 80 projecting into the interior of the housing with recesses 49 therein are provided, as well as fixed contacts 16, 19 to 24 which are fixedly attached to the inside of said housing 11, a rotor which is rotatably mounted inside the holder 1, 11 and is provided with coupling means 51 for its rotational drive by actuation of the ignition key, a rotatable slider 9 which is connected to the rotor 8 in a rotationally fixed manner and is installed so as to be axially movable in relation to it, as well as movable contacts 61 which are fixedly attached to the slider 9, to interact with the mentioned fixed contacts 16, 19 to 24 and to establish electrical circuits in certain angular positions depending on the position of the ignition key.

The anti-theft switch fulfills the following functions:

- Position 0 - "Parking position" contact with locking of the steering column and possibility of switching on the "parking light".

- Position 1 - "Accessories" contact, especially for switching on the radio.

- Position 2 - Contact "Accessories" and "Ignition".

- Position 3 - Contact "ignition" and "starter" and "control".

Positions 0, 1, 2 are stable positions with the help of locking means 4, 5, 56, while position 3 is unstable and is returned to position 2 by a return spring 2.

In position 1, the slider 9 establishes a connection between the fixed contact 21, which is here connected to the positive terminal of the battery, and the fixed contact 16 (accessory contact).

In position 2, the slider 9 establishes a connection between the contact 21 and the contacts 16 and 22 (the ignition coil power supply contact). In position 3, the slider 9 establishes a connection between the contact 21 and the contacts 22 and 19 (the starter contact) with the help of the anti-reverse device 7 and the spring latch 6, the anti-reverse device and the rotor each having a slope and a recess for the spring latch 6 and their mutual locking, so that it is not possible to operate the starter twice in succession without returning to the starting position.

In position 0, a connection is made between the contact 21 and the fixed contact 20 (parking light). For further details, see the above-mentioned documents FR-A-2 019 972 and FR-A-2 373 138.

The housing 11 in single-block design consists here of two parts, namely a cylindrical part 43 with catches 44 and a projection 45 for plugging onto the body 1 and a connecting part 41 for forming a plug connector, the said parts 41, 43 being separated from each other by the base 42. This base 42 is provided with passages 46 and has depressions 49 which are formed in projecting over-thicknesses 80 which here run axially from the base 42 in the opposite direction to the part 41.

The over-thicknesses 80 extend into the interior of the housing 11. The recesses 49 are designed in the form of holes.

Having said this, according to the invention a switch of the type mentioned above is characterized in that at least some of said fixed contacts 16 and 19 to 24 are installed in such a way that the parts of the fixed contacts that come into contact with the movable contacts 61 are arranged in an elevated position at a distance from the bottom 42 of the housing 11, said parts forming a recess between said fixed contacts and the bottom 42, and in that at least some of said fixed contacts 16, 19, 20 and 22 to 24 have, on the one hand, a first tongue 91 with hooking means 47 for anchoring in a recess 49 and, on the other hand, a second tongue 92 which are provided with hooking means 47 for anchoring in a passage 46, said passage 46 being arranged at a distance from the recess 49.

In this way, at least some of the fixed contacts 16 and 19 to 24 are arranged to protrude above the floor 42 and are anchored at two locations.

According to a feature of the invention, an optional second switch 13, 17, 18 for inserting the ignition key is installed by means of this recess. This switch is provided on the one hand with a conductive elastic contact blade 17 which can cooperate with one 21 of the fixed contacts, and on the other hand with a plunger 13 which is axially movable against an elastic return means 12 which comes to rest on the bottom 42 of the housing 11, said plunger being guided over the ignition key and can act on the elastic contact blade 17 to open the said circuit. The tappet 13 is provided with a retaining shoulder 71 to cooperate with a retractable stop 74 mounted on the base 42 and directed towards it.

The anti-theft switch is clamped onto a fixed part of the steering lock structure and is designed with an integrated connector.

In particular, the body 1, made in a cylindrical shape, covers the open housing 11 and comprises two fastening lugs 31 (Figures 1 and 2) for fastening by clamping on the part of the steering lock structure with the help of the projecting tongues 33 cut out in the upper part to compensate for the play. This body 1 comprises a central cylindrical sleeve 34 recessed for the installation of the return spring 2 and the creation of a cavity (Figures 2 and 3).

The upper part of this plastic body 1 is provided with a passage 48 for the arms of the return spring 2, which is designed as a helical spring. One of these arms is tensioned by rotation of the rotor 8 from position 2 to position 3 in order to carry out a return. This body 1 also comprises thickness reductions to form holes delimited by retaining tongues 35 and a cutout 37. The tongues 35 can cooperate with catches 44 belonging to the housing 11, while the cutout 37 can cooperate with an anti-rotation projection 45 arranged on the housing 11.

In addition, the body 1 has a shoulder 38 for resting on the free end of the housing 11 (Figure 2). Thanks to this design, the attachment of the Housing 11 on the body 1 by clamping or snapping with the interaction of the catches 44 with the tongues 35 and with the interaction of the projection 45 with the cutout 37, the catches 44 engaging with play in the holes connected to the tongues 35.

The metal contacts 16, 19, 20, 24, 22 and 23 are here each extended by a second tongue 92 which passes through a passage 46 with a bevelled insertion end (Figure 5) and by a first tongue 91 which engages in a depression 49 with a bevelled insertion end to ensure a secure hold and efficient fastening. The contacts 19 and 21 to 24 are arranged to protrude from the base 42, having bent parts to form large contact areas which extend parallel to the base 42. The second tongues 92, which are arranged remote from the first tongues 91, pass through the passages 46 to open into the connection part 41 and form a connector. The recesses 49 are here designed in the form of a blind hole and are arranged away from the passages 46.

The contact 20 is designed in the form of an angle, while the contact 16 has the shape of a rail, on the underside of which a winding projection is provided. The contacts 16 and 19 to 24 are distributed in the circumferential direction as a whole on two concentric tracks, and the moving contacts 61 are in friction with the moving parts (contacts 19 and 21 to 24) or the sections of the contacts 16 and 20, namely raised at a distance from the base 42 in order to free up space inside for the second switch in conjunction with the over-thicknesses 80.

Each tongue 91, 92 is assigned at least one projection 47, here two projections 47, in the form of a tip, which extend on either side of the tongue in question (Figure 2) and are made in one piece with it. In this way, the contacts are firmly inserted into their passage 46 and their respective recess 49, the projections 47 creating grooves in the plastic of the housing so that the said contacts are anchored in the housing 11. The projections 47 form hooking means for the first and second tongues 91, 92. As a variant, the projections 47 can consist of lugs which can be expanded in the extraction direction and which are cut out of the tongues 91, 92.

The large-area contact 21 has only a second tongue 92 with projections 47, which passes through a hole 46 and extends into the connection part 41.

Due to this arrangement, a recess is created between the base 42 and the bent parts of the fixed contacts concerned for the installation of a second switch for inserting the ignition key.

The second switch comprises a plunger 13 and an elastic contact blade 17 connected to an optional additional fixed contact 18 which is fixedly attached to the housing 11. This fixed contact 18 is assembled in the same way as the contacts 16, 19 and 24 and thus has a first 91 and a second tongue 92, one of which passes through the passage 46 with a bevelled end thereto (Figure 5), while the other engages in a recess 49 which also has a bevelled end, each tongue having two projections 47 on the sides which are pressed firmly into the said passage 46 and into the said recess 49.

The additional overthickness 94, which is assigned to the depression 49 of the fixed contact 18, has a limited height so that the contact 18 extends axially below the other contacts. The contact blade 17 is here fixed by rivets to the contact 18, which has a suitably deformed part 83 (Figure 5). As a variant, it can be soldered or screwed on. This contact blade 17 has a central opening 84 through which a nose 53 belonging to the rotor 8 passes, and a curved free end 81 for cooperation with a lug 82 formed by cuts in the fixed contact 21 (Figure 3). The contact blade 17 extends diametrically between the contacts 16 and 21, which are diametrically opposite one another. This contact blade comprises two radially offset arms (Figure 5) connected to the opening 84 by an annular central part.

The slider 9 is provided with a cutout for enclosing the nose 53 (Figure 1) and comprises a total of three arms with three projections directed towards the base 42 to form movable contacts 61, which are thus made here by locally recessing the slider 9. As a variant, these contacts 61 can be attached to the said slider.

The tappet 13, made of plastic, is arranged in the middle of the housing 11. It extends along the axis of the housing 11 and comprises a spindle 73. This spindle 73 engages in a central bore 55 of the rotor 8. The rotor 8 has a hollow cylindrical shape, with the nose 53 extending towards the bottom 42 of the housing 11, while a stepped cylindrical insert 52 extends outwards to rotately cooperate with the inner bore of the sleeve 34 of the body 1.

This insert 52 is provided with a recess 51, here in the form of a keyhole, which contains coupling means, here with a finger, which is operated by the ignition key of the steering lock. In this way, the rotational drive of the rotor 8 takes place from the ignition key, whereby it is mounted in a rotating manner inside the body 1.

This rotor 8, made of plastic, is provided with catches 56 for cooperating with a ball 3, on which a spring 4 rests on the body 1 acts, and for forming the locking means described above for locking the positions 0, 1, 2 of the switch. This hollow rotor 8 also comprises a lateral projection 54 which can engage in a form-fitting manner in a cutout 60 of the slide 9. This slide 9 is acted upon by three springs 10 which are inserted in recesses in the rotor 8 which extend towards the base 42 (Figure 2). The slide 9 is thus mounted so as to be axially movable in relation to the rotor 8, counter to the action exerted by the springs 10, while at the same time being connected in a rotationally fixed manner to the said rotor 8 by the cutout 60.

In addition, this rotor 8 has a housing (Figure 2) for the insertion of the contact pin 15, on which a spring 14 acts, which is inserted into said housing and into a blind hole provided on said contact pin 15, which can cooperate with a V-shaped track arranged in a projecting manner on an overthickness 95 of the housing base (Figures 3 and 5). This contact pin can establish a contact between the fixed contacts 23 and 24 when the switch is in position 3, for example to switch on a brake warning light.

The contacts 24 and 23 are optional, as is the second switch, which is made possible by the configuration of the housing 11 with recesses 49 and passages 46, whereby the excess thicknesses 80, 94 associated with the depressions 49 are distributed accordingly and stiffen the floor 42.

The retractable stop 74 is formed by means of an elastic tongue 75 which extends axially projecting from the base 42 in the opposite direction to the part 41 (Figure 3).

The stop 74 belongs to an end hook 76 of the tongue 75. This hook 76 has a bevelled insertion part and a shoulder directed towards the base 42, which forms the stop 74 according to the invention.

Since the housing is made of plastic, this tongue 75 - as well as the over-thickness 95, the depressions 49 and their associated over-thicknesses 80, 94 - is produced by molding. For this purpose, the robust base 42 is provided with a demolding opening 78 for the stop 74, whereby this opening 78 extends opposite the hook 76.

The shoulder 71 is formed so as to protrude laterally from the main part 70 of the plunger 13 on its underside. This shoulder also includes a bevelled insertion part. The part 70 is provided with a blind hole for receiving the coil spring 12, which forms an elastic return means. It is connected to the plunger 13 and rests on the base 42 of the housing 11, which is provided with a centering projection for this purpose (Figure 3). This is where the thinnest part of the base 42 is located.

The main part 70 for supporting the spring 12 comprises in its upper region a support finger 72 with a curvature for local contact with the contact blade 17. The finger 72 and the shoulder 71 extend on both sides of the part 70 and the axis of the housing 11 (Figure 3). The attachment point of the contact blade 17 is located near the contact 16 and is closer to the tongue 75 than to the finger 72, so that the distance between the finger 72 and this attachment point is relatively large. This part 70 extends below the contact blade 17 (between the base 42 and this blade) and is extended to form the spindle 73 with passage through the opening 84.

As will be clear, the installation of the plunger 13 is carried out by simply inserting it axially, whereby the shoulder 71 can spread the elastic tongue 75 when the plunger 13 is inserted, whereupon the elastic tongue 75 then returns to its initial position after the plunger 13 has been inserted, against the spring 12. This plunger 13 has two ribs 78 on the sides, which can slidably cooperate with two positive sliding guides 77 that extend axially projecting from the base 42 towards the body 1. In this way, the plunger 13 is secured against rotation and can be moved in a straight line in relation to the housing 11, whereby the sliding guides 77 and the tongue 75 extend on both sides of the housing axis (Figure 5).

After fitting the plunger 13, which is held by the stop, it is only necessary to fit the tongue 17 by inserting the contact 18 into the housing 11 and then to fit the other fixed contacts. Of course, the fixed contacts 16 and 19 to 24 can also be fitted first and then the plunger 13 and the contact blade 17 with its connecting contact 18 can be fitted by elastically deforming the contact blade for passage under the bent part of the contact 21.

The housing 11 further comprises two sliding guides 86 (Figure 5) for the installation of the contact 21 through Insert. This contact 21 has a U-shaped profile with a base side perpendicular to the base 42 and two legs, one of which is in contact with the base 42 and is extended by a second tongue 92 which passes through the associated opening 46, while the second leg is shorter to form the actual fixed contact.

The projection 82 is made by cutting out the base of the U-shape of the contact 21 and extends parallel to the bent part of the contact 21, passing underneath it. The spindle 73 passes through the nose 53, which has an extension for this purpose, and penetrates into the insert 52 and into the recess 51.

As will be clear, when the ignition key is not inserted, a balance is created between the spring 12 and the contact blade 17, which is then at a distance from the projection 82 and the bent part of the contact 21. The stop 74 in any case limits the movement of the contact blade 17 towards the bent part of the contact 21, although the spring can be made stronger. When the ignition key is inserted, it pushes back the spindle 73 of the tappet 13 via a finger (not shown) which positively penetrates the recess 51, so that the curved contact blade 17 comes into contact with the projection 82.

In this context, it is important to note the precision of the operation, since the finger 72 is arranged close to the contact 21 and the length of the contact blade.

When the contact is thus made, a circuit is created from contact 21 to contact 18, which enables the supply of current to a circuit, which is connected to an alarm device in the vehicle, which activates the alarm if, for example, the driver closes his door and has left the ignition key in the steering lock.

As will be clear, the design of the housing allows the second switch and the contacts 23 and 24 to be installed or not as desired, which is made possible by the over-thicknesses 80, 94, 95, which form a grid and create a central recess for the plunger 13.

The location of the sliding guides 77 and the tongue 75 allows good use of the available space as well as efficient support of the tappet 13.

It should also be noted that the metal particles caused by friction between the slider 9 and the fixed contacts are deposited in the bottom of the housing without creating creepage paths. It is also important to note the stability of the contacts 16 and 18 to 24, which is due in particular to the first 91 and second tongues 92 arranged at a distance from one another, as well as the recesses 49 and the corresponding passages, so that the respective contacts are anchored at two points.

As is clear from the description, the position of the stop 74 depends on the specific applications and must allow the downward movement of the plunger 13 when the ignition key is inserted. Here, this stop 74 is arranged under the projection 82, preventing any contact between the constant blade 17 and the bent part of the contact 21.

The present invention is of course not limited to the embodiment described. In particular, the fastening of the bracket 1, 11 to the structure of the steering lock by means of screws or rivets, which also applies to the assembly of the body 1 and the housing 11.

Furthermore, the housing 11 is not necessarily provided with a connection part 41, but the connection can also be made as described in FR-A-2 373 138.

Instead of a mechanical ignition key, an electronic version is also possible, whereby the steering lock then contains a receiver and the electronic key contains a transmitter. The transmitter sends a signal to this receiver to activate an actuating element with which the steering lock is then equipped and which drives the rotor 8, for example via a finger.

As a variant, instead of the sliding guides 77, protruding cylindrical pins can be provided, which are attached to the base 42 and each engage in a hole in order to guide the plunger during its displacement and to form guide means for the rectilinear movement of the plunger 13.

All fixed contacts can be provided with a bend overlying the base 42. All this depends on the specific applications and the space available, whereby the contact 21 can also be connected to the negative terminal of the battery, depending on the application.

The housing 11 can consist of another electrically non-conductive and malleable material that allows the contact tongues to be firmly inserted, while the locking means 3, 4, 5, 6 can act radially.

Claims (12)

1. Electric anti-theft rotary switch for motor vehicles, which can be activated at the user's choice by means of the ignition key, in the embodiment comprising a body (1) which is assembled with a housing (11) made of electrically non-conductive and malleable material, such as plastic, to form a support (1, 11) for attachment to the structure of the steering lock, said housing being hollow, open and provided with a bottom (42) in which passages (46) and over-thicknesses (80) projecting into the interior of the housing (11) with recesses (49) therein are provided, and also with fixed contacts (16, 19 to 24) fixedly attached to the inside of said housing (11), a rotor (8) which is mounted rotatably inside the support (1, 11) and is provided with coupling means (51) for its rotational drive by actuation of the ignition key, a rotatable slide (9) which is fixedly connected to the rotor (8) and is mounted so as to be axially movable relative thereto, and with movable contacts (61) fixed to the slider (9) so as to cooperate with said fixed contacts (16, 19 to 24) and to establish circuits in certain angular positions depending on the position of the ignition key, characterized in that at least some of said fixed contacts (16 and 19 to 24) are mounted so that the parts of the fixed contacts which are the movable contacts (61) are arranged raised at a distance from the bottom (42) of the housing (11), these parts forming a recess between said fixed contacts and the bottom (42), and in that at least some of said fixed contacts (16, 19, 20 and 22 to 24) have, on the one hand, a first tongue (91) with hooking means (47) for anchoring in a recess (49) and, on the other hand, a second tongue (92) provided with hooking means (47) for anchoring in a passage (46), this passage (46) being arranged at a distance from the recess (49). 2. Switch according to claim 1, characterized in that the said recesses (49) consist of blind holes. 3. Switch according to claim 1 or 2, characterized in that at least some of the fixed contacts (16, 19 to 24) are provided with bent parts extending parallel to the bottom (42) of the housing (11) for the purpose of cooperating with the movable contacts (61). 4. Switch according to one of claims 1 to 3, characterized in that the passages (46) and the recesses (49) are provided with a beveled end. 5. Switch according to one of the preceding claims, characterized in that an additional overthickness (94) with a recess (49) and limited height is provided for the installation of an additional fixed contact (18). 6. Switch according to claim 5, characterized in that the additional fixed contact (18) comprises a first tongue (91) and a second tongue (92) for installation in the recess (49) of the additional excess thickness (94) or in a passage (46) in the bottom (42) of the housing (11). 7. Switch according to claim 6, characterized in that an elastic contact blade (17) belonging to a second switch for inserting the ignition key has an end which is fixed to the additional fixed contact (18). 8. Switch according to one of the preceding claims, characterized in that the housing (11) has an elastic tongue (75) with a terminal hook (76) which projects from the base (42) to retain a plunger (13) belonging to a second switch for inserting the ignition key. 9. Switch according to claim 8, characterized in that the base (42) of the housing (11) has axially projecting sliding guides (86) as a guide for the linear movement of the plunger (13). 10. Switch according to one of the preceding claims, characterized in that, in order to form the hooking means, each first (91) and second (92) tongue has two projections (47) in the form of a point extending on either side of the tongue in question. 11. Switch according to one of the preceding claims, characterized in that the second tongues (92) pass through the passages (46) to open into a connection part (41) belonging to the housing (11). 12. Switch according to one of claims 3 to 11, characterized in that the fixed contacts (16 and 19 to 24) are distributed in the circumferential direction on two concentric tracks and that the excess thicknesses (80, 94) form a grid with a central recess.