GB2096235A

GB2096235A - Device for controlling the illumination range of headlamps

Info

Publication number: GB2096235A
Application number: GB8209744A
Authority: GB
Original assignee: Westfaelische Metall Industrie KG Hueck and Co
Current assignee: Westfaelische Metall Industrie KG Hueck and Co
Priority date: 1981-04-02
Filing date: 1982-04-01
Publication date: 1982-10-13
Also published as: GB2096235B; FR2503064A1; SE8201837L; ES272672Y; SE437496B; DE3113252A1; FR2503064B1; DE3113252C2; ES272672U

Abstract

A device for controlling the illumination range of a vehicle headlamp has a retaining device (15) which is secured to the vehicle and in which an adjusting member (2) for the illumination-range control is retained, a ball-and-socket connection (6, 8) joining the adjusting member to a pivotably mounted headlamp part (5). The ball and the socket have corresponding clearances (7, 9) which are distributed over the periphery and which coincide with one another in a first angular position to allow the ball to be slid into the socket with an axial movement, and which can then be located behind one another when there is relative rotation between the ball and socket about an angle corresponding approximately to the angular extent of the clearances, the ball and socket being thereby interengaged to move together in the direction of said axial movement. <IMAGE>

Description

SPECIFICATION Device for controlling the illumination range of headlamps The invention relates to a device for controlling the illumination range of headlamps, especially for motor vehicles.

A device for controlling the illumination range of headlamps for motor vehicles is known from German Auslegeschrift 2361959, in which a retaining device is fastened to the vehicle and supports an asjusting member for the illuminationrange control, that member being articulated by means of a ball-and-socket connection to a connecting part which is fastened to the pivotably mounted headlamp part. In this device, a great disadvantage for assembling the adjusting member on the headlamp part is that the ball-andsocket connection can be obtained only by using considerable force to engage the claw-like walls of the socket round the ball, relying on the resilience of the socket. Even when the adjusting member is removed from the headlamp part, for example when the headlamp is exchanged in the workshop, the ball has to be disengaged from the socket with the use of force.Although catch pins which are made of steel and which are driven through the ball offer protection against rotation for the ball pin, nevertheless over a relatively long period of operation their associated guide slots consisting of plastics can be deformed as a result of continual vehicle vibration, so that precise control of the illumination range is put in doubt, and at an advanced stage there is the danger that the balland-socket connection will break. Also, provision of the catch pins involves extra production costs.

Without the use of catches or the like, there is, in particular, the danger that if there are wide tolerances, the ball-and-socket connection will open by itself while if there are small tolerances the connection can be assembled and removed only with excessive force and moves with difficulty, especially as temperature differences during operation and signs of ageing of the parts, usually made of plastics have to be taken into account.

According to the present invention, there is provided a device for controlling the illumination range of a headlamp comprising an adjusting member for effecting the illumination range control and connected by means of a ball-andsocket connection to a member arranged to be secured to a movably mounted headlamp part, in which the ball and the socket have clearances distributed over their peripheries which correspond with each other and which coincide with one another in a position in which the balland-socket connection is interconnected in a straight line, and which can be positioned behind each other by relative rotation through an angle corresponding approximately to the angular extent of the clearances.

With such an arrangement, after the ball and socket have been inserted into one another, a rotation through the appropriate angle is sufficient to secure the ball-and-socket connection, and it is not necessary to configure the parts in such a manner that force has to be used to make the connection.

In a preferred form of device according to the invention, the adjusting member is secured in a retaining member in the manner of a bayonet connection, and corresponding angular movements are involved in engaging operatively both the bayonet lock of the adjusting member and the components of the ball and socket connection. It can thus be ensured that, when the adjusting member is assembled on that part of the headlamp fixed to the vehicle, a movable part of the adjusting member, which carries the socket at its end, and which may be formed as a piston, at the same time also locates the socket without force onto the ball of the connecting member attached to the movably mounted headlamp part (reflector).

As a result of the rotation of the adjusting member through the appropriate angular extent in the bayonet lock form of engagement, the piston, together with the socket, is also rotated at the same time. By arranging that corresponding angles of rotation are required to make the bayonet lock engagement of the adjusting member and also the ball-and-socket connection between the adjusting member and connecting member, the ball-and-socket connection is securely completed without the ball or the socket having to be visible to the fitter. The ball and socket can, for example, be located in a space which cannot be inspected, and brought together unseen. Advantageously the socket wall is rigid, which is made possible because the conventional manner of engaging a ball and socket joint, described in the opening paragraphs, is avoided.A large holding force can be achieved as a result, and it is possible to omit the retaining ring which is conventionally placed round the socket wall.

An embodiment of the invention will be described in more detail with reference to the accompanying drawings, in which: Fig. 1 shows, in section, a headlamp with a device according to the invention for illuminationrange control, Fig. 2 shows a section along the line A-A in Fig. 1, and Figs. 3 and 4 show respectively, a plan view and a side view of the ball of the device in Figs. 1 and 2.

In the drawings, a headlamp housing 1 is mounted fixedly on a vehicle not shown in any detail, and serves, at the same time, as a retaining device 1 5 for an adjusting member 2. The headlamp reflector 3 is mounted movably in the headlamp housing 1 on a horizontal transverse pivot and is connected firmly by its edge 4 to one end of a connecting member 5. The other end of the connecting member 5 is designed as a ball 6 with clearances 7 distributed around its periphery and provides a relatively firm connection with a socket 8. In their final positions, the ball is located in a portion of the socket having a spherical interior closely matched to the maximum diameter of the ball. In its forward region through which the ball passes to reach the final position, however, the socket has clearances 9 which correspond peripherally to the clearances 7 of the ball 6.

A rearward extension of the socket 8 is formed, for example, as a piston 10 which is axially displaceable in a piston guide of the adjusting member 2 by means of a hydraulic drive. Guide lugs of the piston 10, which seat in recesses located in the piston guide, ensure retention of the piston 10 against rotation relative to the adjusting member 2. A sealing ring 11 between the headlamp housing 1 and adjusting member 2 also ensures, at the same time, the take-up of axial play between the adjusting member 2 and the headlamp housing 1. A knurled nut 12 and a movable part 14 provided with a screw thread 13 serve for basic adjustment of the reflector 3 attached movably in the headlamp 1 about its horizontal transverse pivot axis.

The section along the line A-A, shown in Fig. 2, illustrates the parts before the ball-andsocket connection is secured. From this figure can be seen the respective clearances 7,9 of the ball 6 and socket 8, these clearances being formed by uniformly distributed series of projections and recesses which have a complementary configuration on the respective parts.

As can also be seen from Fig. 2, as part of the bayonet lock connection the retaining device comprises a series of inward radial projections 1 7.

These projections terminate short of the front face of the retaining device so that arcuate recesses 16 are formed in that face. Lugs 1 8 on the adjusting member can be inserted axially through the slots formed between adjacent projections 17, and by a rotation of the adjusting member these lugs are engaged in the recesses 16, the resilient sealing ring 11 then being in a compressed state and providing a retaining force that holds the lugs against the rear faces of the recesses. The adjusting member 2 is thus held securely in a fixed position in the lamp housing 1.

During assembly, the adjusting member 2 together with the socket 8 is brought up to the headlamp housing 1 in a straight line, with the lugs 1 8 passing through the slots defined between the projections 17, i.e., while in the relative angular orientation shown in Fig. 2, and in this orientation the clearances 7 of the ball are also aligned with the clearances 9 of the socket 8.

When the adjusting member 2 is rotated, through 60 degrees in the illustrated example, the member 2 is connected firmly to the retaining device 15, and therefore to the headlamp housing 1, by the bayonet lock connection of the lugs 1 8 in the recesses 1 6 as already described. The angular extent of the recesses 1 6 corresponds to the angular movement required to engage the bail and socket operatively. Since the piston 10 participates in the assembly movements of the member 2, the ball-and-socket connection 6, 8 is also made at the same time, without a special operation being necessary and especially also without the engagement of the ball-and-socket connection having to be checked visually.

The illumination range for the motor vehicle headlamp is controlled as follows: when readjustment of the headlamp becomes necessary because of a change in the vehicle load, the piston 10 is displaced in the adjusting member, automatically or even by hand by the unillustrated hydraulic drive, so far that the reflector 3 of the headlamp 1 is pivoted about its horizontal axis via the ball-and-socket connection 6, 8 and the connecting member 5, until the illumination beam range corresponding to the basic setting is reached again and dazzling of the oncoming traffic is thereby avoided. The basic setting of the reflector 3 is adjusted by means of the knurled nut 1 2 by varying the effective length of the movable part 14 by rotating the knurled nut 12 on the screwthread 1 3.

In more detail, the piston 10 can form the piston of a hydraulic piston-and-cylinder arrangement its hollow interior being closed at the rear. The nut 12 is mounted rotatably on the adjusting member 2 but is axially fixed on the member. The movable part 14 is, in effect a separate element of the adjusting member fixed rotationally relative to the forward part having the lugs for the bayonet lock connection, e.g. by the guide lugs already referred to, but displaceable axially thereon. The part 14 may be integral with the hydraulic cylinder or be axially fixed thereto.

Rotation of the nut 1 2 engaging the screw thread 1 3 therefore produces a relative axial displacement between the piston and cylinder giving a pivoting movement of the headlamp reflector for an initial adjustment setting of the device.

When the adjusting member 2, the reflector 3 of the headlamp 1 is to be exchanged, it is sufficient to rotate the member 2 through the appropriate angle to free the connection axially.

The adjustment member 2 and the ball-andsocket connection 6, 8 which also serves as a coupling to the reflector 3, are thereby simultaneously disengaged quickly and easily from the headlamp housing 1 without the use of force, just as the parts are joined together without the use of force.

While a principal feature of the illustrated device lies in the manner in which the ball-andsocket connection can be made without the use of force, the bayonet-lock connection itself provides a positive means of location of the ball-and-socket connection that can be employed even in devices which rely on a resilient or force fitting of the balland-socket connection, in that its use is able to ensure positively that the ball-and-socket connection is made without requiring these parts to be visible when the connection is made.

Claims

1. Device for controlling the illumination range of a headlamp comprising an adjusting memberfo effecting the illumination range control and connected by means of a ball-and-socket connection to a member arranged to be secured to a movably mounted headlamp part, in which the ball and the socket have clearances distributed over their peripheries which correspond with each other and which coincide with one another in a position in which the ball-and-socket connection is interconnected in a straight line, and which can be positioned behind each other by relative rotation through an angle corresponding approximately to the angular extent of the clearances.

2. Device according to claim 1 wherein the ball and socket are arranged to be locked together by an angular movement substantially equal to the angular extent of an individual clearance.

3. Device according to claim 1 or claim 2, wherein the clearances are distributed substantially uniformly around the periphery of the ball and the socket.

4. Device according to claim 3 wherein the ball and/or the socket has three clearances at an angular pitch of 1200.

5. Device according to claim 4 wherein the respective clearances on the ball and on the socket have an approximate angular extent of 600.

6. Device according to any one of the preceding claims wherein the actuating member is retained in the retaining member in a bayonet-locking manner, and the angular extent of the bayonetlocking retention of the adjusting member corresponds to that of the adjusting member/connecting member connection.

7. Device according to any one of the preceding claims further comprising a headlamp housing arranged to be mounted fixedly on the vehicle and serve as a retaining member of the device, and the connecting member for the movably mounted headlamp part is arranged to engage on the reflector of the headlamp.

8. Device according to any one of the preceding claims wherein the adjusting member is mounted for straight8line movement in a guide arranged to be mounted in a fixed position on the vehicle.

9. Device according to claim 8 wherein the adjusting member is formed as or comprises a piston of a piston-and-cylinder arrangement of a hydraulic actuating mechanism.

10. Device according to claim 9 wherein guide lugs on the piston are located in complementary recesses in the piston guide.

11. Device according to any one of the preceding claims wherein means are provided on the adjusting member for an initial or basic adjustment of the headlamp movable part about a transverse horizontal axis.

1 2. Device according to claim 1 wherein said adjustment means is a screw-thread mechanism comprising a nut embracing the adjusting member and arranged to displace a threaded screw element axially.

1 3. Device for controlling the illumination range of a headlamp constructed and arranged for use and operation substantially as described herein with reference to the accompanying drawings.

14. Device for controlling the illumination range of a headlamp comprising an adjusting member connected by means of a ball-and-socket connection to a member arranged to be pivotally secured to a movably mounted headlamp part, the ball having at least one part-peripheral recess and/or projection and the socket having an entry region comprising one or more corresponding projection(s) and/or recess(es) through which said ball recess(es) and/or projection(s) can be slid by an axial movement to locate the ball in the socket, the ball and socket then being relatively rotatable about the axis of said locating movement to bring said recess(es) and/or projection(s) to positions in which they block a return axial movement, whereby the ball is operatively engaged in the socket.

1 5. Device according to claim 14 wherein said adjusting member is secured in position by a bayonet lock form of engagement and wherein corresponding angular movements are required to operatively engage said bayonet-lock engagement and said ball-and-socket connection, one element of said connection being rotationally fixed relative to the adjusting member whereby both the bayonet-lock engagement and the ball-and-socket connection are made simultaneously.

1 6. A vehicle headlamp provided with a device according to any one of the preceding claims.