FR2871120A1 - Ball and socket joint device for headlight of motor vehicle e.g. car, has fastening body comprising retaining flanks to force ball and socket joint head in radial direction when head is stressed by extraction force - Google Patents

Abstract

The device has a fastening body (12) comprising retaining flanks (36) to force a ball and socket joint head (14) in a radial direction when the head is stressed by an extraction force (F) along an axis (13). The flanks are actuated by plane return surfaces (34) of respective blades (24) for exerting the radial force on the head. The surfaces are disposed in an intermediate position between axes of the blades and the flanks. An independent claim is also included for a headlight for a motor vehicle comprising a ball and socket joint device.

Description

2871120 1

  The present invention relates to a ball joint device of a projector for vehicles, in particular for motor vehicles.

  As is known, projectors for motor vehicles comprise an envelope which is able to be fixed to a structure of the motor vehicle, a light source and a reflector housed in the envelope, and a closing lens of the envelope , arranged in front of the light source. The reflector transmits the light rays from the light source through the lens and is coupled to the envelope in an adjustable position so as to be able to orient the light beam transmitted according to the light distribution to be delivered and according to the charge of the light. motor vehicle, in accordance with the requirements imposed by the traffic and international regulations.

  In particular, the reflector is coupled to the envelope at three attachment points by means of respective hinge devices. One of these points is arranged in a fixed position, while the other two attachment points are generally on a vertical plane and, respectively, on a horizontal plane parallel to the optical axis of the reflector, are coplanar to the fixed point in these planes and are movable along the respective direction parallel to the optical axis to vary the orientation of the reflector around the fixed point. In general, the position of the attachment point on said horizontal plane and defining the horizontal adjustment of the reflector is adjustable by means of manually operated screws, while the position of the attachment point on said plane vertical and which defines the vertical adjustment of the reflector is adjustable by means of electromechanical actuators.

  Each of the ball joint arrangements that define the attachment points comprises a pivot and an attachment body, or "pad", attached to the casing and the other to the reflector. The block defines a spherical or cylindrical seat, while the pivot ends with a spherical head, which engages the seat and is retained in engagement along the axis of the pivot by the assembly action of two wings carried by the pavement. In particular, the fins define between them an opening traversed by a portion of the pivot, are coupled in axial abutment against a rear portion of the spherical head of the pivot and have planar return surfaces converging with each other to facilitate the axial insertion of the spherical head in the seat during assembly.

  In the ball joint devices described above, the retaining action exerted by the fins on the spherical head is unsatisfactory, in particular when wear phenomena due to all vibrations and all the mechanical stresses to which the moving car is subjected.

  Because of this wear and also the coupling games between the seat and the ball head due to the tolerances of the mounting work, the spherical head tends to move in the seat, with consequent reflector movements relative to the seat. envelope and, consequently, variations in the orientation of the projected light beam relative to the adjustment made.

  In particular, when the motor vehicle is running, the stresses tend to vibrate the reflector and, consequently, to make the orientation of the projected beam of light unstable. These reflector vibrations become tedious for the driver of the motor vehicle and also for drivers of motor vehicles arriving in the opposite direction. The latter are indeed dazzled intermittently when the reflector, when moving, does not manage to maintain the light beam below the correct inclination down, but also sends it upwards outside the limit required lighthouses in code.

  With the use of the motor vehicle, the wear of the parts of the ball joint device increases with the consequence of increasing vibration and mechanical stress, which can cause the stall and rupture of the ball joint device him itself, which makes the projector nonoperating. Such a problem actually hinders the movement of the motor vehicle until the projector is replaced with delays and significant costs for the user.

  In addition, the flat return surfaces of the fins are not always effective during assembly. In particular, the axial insertion under pressure of the spherical head into the seat is found to be defective when the pivot is relatively long and, because of inaccuracies in positioning, it is pushed in a direction which is not perfectly orthogonal to the opening between the fins, so that the spherical head tends to slide along the flat return surfaces instead of entering the seat and the pivot, this time, deforms or breaks. Obviously, in these cases it is necessary to repeat the insert operation or to directly replace the pivot with consecutive delays in the production cycle.

  The object of the present invention is to provide a ball joint device of a vehicle headlamp, which allows to solve in a simple and economical way the problems described above.

  According to the present invention, there is provided a ball joint device of a vehicle headlight; the device comprising: - a ball head which is able to be connected to one or the other between a reflector and an envelope of said projector; and a fastening body which is able to be fixed to the other between said reflector and said envelope, by defining a ball seat engaged on said ball head and comprising assembly means for holding said head of said ball head; ball joint engaged along a transverse axis to a bottom surface of said ball seat; characterized in that said attachment body comprises movable radial retention means for forcing said ball head in the radial direction when said ball head is biased by an extraction force along said axis.

  Preferably, said radial retaining means are actuated by said biasing means for exerting the radial force on said ball head.

  The invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting embodiment thereof and in which: FIG. 1 illustrates in cross-section and with portions removed for clarity, a preferred embodiment of a ball joint device of a vehicle headlamp according to the present invention; FIG. 2 schematically illustrates a section of a vehicle headlamp provided with the device of FIG. 1; and 2871120 4 - FIG. 3 is a perspective view of a detail of the device of FIG. 1.

  In FIG. 2, the reference numeral 1 indicates, as a whole, a projector (illustrated schematically) comprising an envelope 2 which is able to be fixed to a structure of a vehicle, in particular a motor vehicle, a light source 3 and a reflector 4 housed in the casing 2, and a transparent wall 5 which closes the casing 2 frontally. The reflector 4 transmits the light rays emitted by the source 3 through the wall 5 and is coupled to the casing 2 at three points of attachment, only two of which are illustrated.

  A first of these attachment points, indicated at 6a at the top in FIG. 2, is fixed. A second attachment point, indicated at 6b below in FIG. 2, is disposed substantially on a vertical plane parallel to a reference axis 7 of the projector and passing through the first attachment point 6a.

  The third attachment point (not shown) is disposed substantially on a horizontal plane by the axis 7 and passing through the first point of attachment 6a.

  The second and the third points of attachment are movable along respective directions 8 parallel to the axis 7 to vary the orientation, by means of screws or other suitable means, of the reflector 4 around the point of attachment fixed and, consequently, the orientation of the beam of light transmitted to the outside.

  Each attachment point is defined by a ball joint device 9 comprising a pivot 10, whose end portion 11 is connected to the casing 2, and a fastening body 12 fixed to the reflector 4 (according to a variant not illustrated, the pivot 10 is connected to the reflector 4, while the fastening body 12 is attached to the casing 2).

  Referring to FIG. 1, the pivot 10 has an axis 13 and comprises, at the opposite end of the portion 11, a ball head 14 defined by a hemispherical surface 15 and a flat annular surface 16, which is orthogonal to the axis 13 and connects a posterior circular edge of the surface 15 to an intermediate portion 17 of the pivot 10.

  Referring to FIGS. 1 and 3, the fastening body 12 is made in one piece and comprises two adjacent parts 18, 19, among which the part 18 is drilled so as to be fixed to the reflector 4 by means of a screw (not illustrated ), while the portion 19 has a U-shape and defines an elongated seat 21 along an axis 21, in which, in use, is the center of the surface 15. The seat 20 is engaged on the head 14 and has a semi-cylindrical bottom surface 23, symmetrical with respect to a median plane P on which the axis 21 is located, and having a radius of curvature substantially equal to that of the surface 15.

  The portion 19 carries two fins 24, which are housed in the seat 20 facing each other, are symmetrical with respect to the plane P and are substantially parallel thereto. The fins 24 comprise respective parts 26, which define between them an opening 27 through which the portion 17 of the pivot 10 passes and are united to the part 19 by means of respective weakened connection zones 28, namely zones having a reduced cross-section. 26 zones define two virtual hinges, whose axes 29 are parallel to the axis 21, so that the fins 24 are elastic around the axes 29 in opposite directions with respect to a position of undistorted rest.

  The parts 26 furthermore have respective return surfaces 32 which are convergent with one another and have concavities facing each other in order to guide the head 14, during assembly, towards a central insertion axis 33 located in the plane P and orthogonal to the axis 21. In particular, the surfaces 32 are concave, whether they are sectioned by planes orthogonal to the axis 21 (FIG.2) or by parallels to the axis 21.

  The fins 24 have respective flat return surfaces 34 which are transverse to the axis 33 and are coupled in abutment against the surface 16 to axially retain the head 14 in contact with the surface 23. The fins 24 terminate in flanks. respective retainers 36 defining respective concave surfaces 37 having a radius of curvature substantially equal to that of the surface 15 itself.

  As illustrated in FIG. 1, the surfaces 37 are in contact with the surface 15 and clamp the head 14 between them radially.

  In particular, when the pivot 10 is urged by an axial force F so as to pull the head 14 through the opening 27, the surfaces 34, subjected to this force F from the surface 16, cause the rotation around the axes 29 of the vanes 24, which, operating as levers, laterally clamp the head 14 together.

  These levers are of the third type, from the moment when the surfaces 34 are arranged in an intermediate position between the axes 29 and the flanks 36.

  From the foregoing, it is apparent that the head 14 is maintained not only axially between the surfaces 23 and 24, but also radially between the sidewalls 36, which makes the coupling of the pivot 10 to the fastening body extremely stable. 12 and, consequently, the position of the reflector 4.

  In particular, in all the operating phases, the head 14 is always in contact with the sidewalls 36, so that the surfaces 37 hold the head 14 in the radial direction and increase the load necessary to axially pull the head 14 of the seat 20: indeed, any axial withdrawal of the head 14 through the opening 27 is prevented by clamping the surfaces 37 against the head 14.

  This clamping, as described above, is caused by the rotation of the fins 24 about the axes 29, following the axial pressure acting on the surfaces 34, and is even more important than the extraction force F is high.

  The radial retaining action then becomes even more efficient by the curvature of the surfaces 37 and the configuration of the fins 24.

  In addition, the vanes 24 flexing elastically about the axes 29 constantly follow the possible displacements of the head 14 and therefore have a tendency to dampen the vibrations induced on the reflector 4 when the vehicle is moving, with the consequence of a better stability in the orientation of the projected light beam and a consequent decrease in wear in the coupling areas between the pivot pin 10 and the attachment body 12, compared to known solutions which are not provided with sidewalls 36.

  In addition, the hinge zones 28, which have less thickness relative to that of the parts 26, make it possible to keep the axial insertion load of the head 14 in the seat 20 relatively low, by facilitating assembly relative to the known solutions. The axial insertion of the head 14 during assembly is also facilitated by the surfaces 32, which guide the head 14 towards the center of the opening 27, even when the position of the head 14 is not perfectly aligned with the required position, and therefore avoid the sliding of the pivot 10 on the parts 26 towards the end of the opening 27.

  From the foregoing, finally, it appears obvious that device 1 described and illustrated, modifications and variants can be made while remaining within the scope of protection of the present invention.

  In particular, the bottom surface 23 of the seat 20 could be semispherical instead of cylindrical, and complementary to the surface 15, or all the surfaces of the coupling 15, 23, 37 and / or 16,34 could have any which profile allows in any case the mutual engagement and / or the reciprocal function of ball and / or support. In addition, the flanks 36 could be part of fins distinct from the surfaces 34.

2871120 8

Claims (10)

  1. Device (9) for articulating a ball head of a projector (1) for vehicles; the device comprising: - a ball head (14) which is capable of being connected to one or the other between a reflector (4) and an envelope (2) of said projector (1); and - a fastening body (12) which is able to be fixed to the other between said reflector (4) and said casing (2), by defining a ball seat (20) engaged on said ball head (14) and comprising connecting means (34) for holding said ball head (14) in engagement along an axis (13) transverse to a bottom surface (23) of said ball seat (20); characterized in that said attachment body (12) comprises movable radial retention means (36) for forcing said ball head (14) in the radial direction when said ball head (14) is biased by a force of extraction (F) along said axis (13).   2. Device according to claim 1, characterized in that said radial retaining means (36) are actuated by said biasing means (34) for exerting the radial force on said ball head (14).   3. Device according to claim 2, characterized in that said radial retaining means (36) comprise a retaining surface (37) carried by at least one movable fin (24) housed in said seat ball (20).   4. Device according to claim 3, characterized in that said radial retaining means (36) comprise two retaining surfaces (37) carried by the respective movable fins (24) facing each other.   5. Device according to claim 3 or 4, characterized in that each of said fins (24) carries said assembly means.   6. Device according to any one of claims 3 to 5, characterized in that each of said fins (24) is elastic around a relative virtual hinge (28) defined by a reduced section area.   7. Device according to claims 5 and 6, characterized in that said connecting means comprise an assembly surface (34) disposed in an intermediate position between said virtual hinge (28) and said retaining surface (37) and disposed in abutment against a rear edge of the ball head (14).   8. Device according to any one of claims 3 to 7, characterized in that said retaining surface (37) is concave and has a radius of curvature substantially equal to that of said ball head (14).   9. Device according to any one of the preceding claims, characterized in that said attachment body (12) has at least one concave return surface (32) for the axial insertion of the ball head (14) in the ball seat (20).   10. Projector (1) for vehicles comprising: - an envelope (2), - a reflector (4) housed in said envelope (2) and - means for connecting said reflector (4) to said envelope (2); said connecting means comprising at least one ball joint device (9) made according to any one of the preceding claims.