GB1571226A

GB1571226A - Apparatus for testing the alignment of vehicle headlights

Info

Publication number: GB1571226A
Application number: GB3795577A
Authority: GB
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1976-09-17
Filing date: 1977-09-12
Publication date: 1980-07-09
Also published as: DK412277A; FR2365116A1; DE2641878C2; DK146577C; FR2365116B1; DE2641878A1; IT1113617B; DK146577B

Description

(54) APPARATUS FOR TESTING THE ALIGNMENT OF VEHICLE HEADLIGHI S (71) We, ROBERT BOSCH GMBH, a German company of Postfach 50, 7000 Stuttgart 1, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention is concemed with apparatus for testing the alignment of vehicle headlights.

Such an apparatus is known in which a strip light projector is provided for aligning the aligning apparatus with the transverse axis of the motor vehicle to be tested. This strip light projector is supported by support means at the upper end of the chassis of the aligning apparatus. The provision of such a strip light projector increases the cost of the apparatus and also requires an additional energy supply through a transformer and a supply cable which may break down when using the apparatus.

We have now developed a simpler aligning apparatus for vehicle headlights which does not include a strip light projector and which enables the apparatus to be aligned in a simple, rapid and accurate manner. In particular, aligning of the apparatus can be carried out without any wasteful movements by the operator because the apparatus is ergonomically designed.

According to the present invention, there is provided apparatus for testing the alignment of vehicle headlamps, which comprises a chassis consisting of a base and a column, an optical system carrier mounted on the column, and an adjustable aligning device for aligning the apparatus with the motor vehicle to be tested, the aligning device comprising a single reflecting element bearing at least one reference line extending uansversely with respect to the optical axis of the optical system and the reflecting element being pivotally mounted for rotation about an axis coincident with or parallel to the reference line, on an arm mounted near the upper end of the column.

In order that the invention may be more fully understood, preferred embodiments thereof will now be described, by way of example, with reference to the accompanying drawings: Figure 1 is a perspective view of a first embodiment of aligning apparatus and of the vehicle to be tested therewith, Figure 2 is a perspective view of a second embodiment, and Figure 3 is a cross-section of the reflecting element of a third embodiment.

Figure 1 shows an apparatus 10 for testing the alignment of vehicle headlights, the chassis 11 of which consists of a base 12 which is adapted to travel on rails and a column 13 rotatably mounted on the base 12. An optical system carrier 14 is mounted on the column 13 and is adjustable in height, but secured against rotation, thereon. A mounting 16 for an arm 17, at the free end of which a mirror 18 is pivotally mounted, is located at the upper end 15 of the column 13. The mirror 18 has a flat, longitudinally extending reflecting surface 19 and carries a reference line 22 along its longitudinal centre line and parallel to its long outer edges 21. The reference line 22 is transverse to the optical axis of the optical system in the carrier 14. The mirror 18 is mounted for rotation about its own longitudinal axis and also, together with the arm 17, about the mounting 16.Thus, in any position of the mirror 18, the reference line 22 extends transversely with respect to the optical axis of the optical system, the support 14 of which cannot rotate with respect to the column 13. The mounting 16 is so constructed that the arm 17 is readily adjustable by hand, but maintains the mirror 18 in any adjusted position. A rotary knob 23 is provided at the upper end 15 of the column 13 co-axially with respect to the longitudinal axis thereof. Together with transmission members and eccentrics, not shown, it forms a rotary device located inside the column 13 whereby manual operation of the knob 23 effects rotation of the column 13 relatively to the base 12. The frictional relationships in the rotary device are such that the latter is self-locking so that the column 13 is non-rotatably connected to the base 12 as long as no torque is applied to the rotary knob 23.

This rotary device is more fully described and claimed in our Application 37777/77 (Serial No. 1 571 225).

Tbe arm 17 is preferably so dimensioned that it supports the mirror 18 at such a distance from the rotary knob 23, that the mirror is at or above eye level of an operator standing on the ground behind the apparatus (relative to the vehicle being tested) while it can be reached by the operator's hand. The rotary knob is also readily within reach of the operator. Thus, the mirror 18 and the rotary knob 23 can readily be adjusted simultaneously while the mirror is in the field of vision of the operator.

The method of operation of the aligning apparatus 10 will now be described: the apparatus 10 is wheeled on the rails in front of the headlight of a vehicle to be tested and is then aligned laterally and vertically substantially with the optical axis thereof. By moving the arm 17 and the mirror 18, the operator then searches by eye for two definite points 24, 25 on the front bodywork of the motor vehicle so that these points 24, 25 coincide substantially with the reference line 22 on the reflecting surface 19. Then, by actuating the rotary knob 24, the mirror 18 together with the column 13 can be so rotated with reference to the base 12 that the two points 24, 25 exactly coincide with the reference line 22, whereupon the desired alignment of aligning apparatus 10 with respect to the vehicle is achieved.During this aligning procedure, the arm 17 only needs to be moved in the mounting 16 if another operator of a different height has previously used the apparatus 10. With the same operator, the arm is initially moved into such a position that the entire width of the vehicle can be seen in the mirror 18 and thus two points appropriate to one another can be aimed at. Thereafter, a slight movement of the mirror 18 about its axis is normally sufficient to bring the two points on to the reference line. The position of the mirror 18 relative to the aligning apparatus 10 is such that the operator can easily reach and move the mirror with one hand while maintaining his line of sight substantially horizontal. At the same time, the operator can easily reach the rotary knob 23 with his other hand and rotate it, this also being within his field of vision while looking at the mirror 18.Thus, it is of particular advantage that the manual actua tions are concentrated within a limited space which favours a simple, rapid and proper alignment because no foot movement is re quired which might interrupt concentration and which could lead to an undesired change in the position of the aligning apparatus 10.

Figure 2 shows a second embodiment of aligning apparatus 30 which differs from that shown in Figure 1, chiefly in being a freely, mobile apparatus with another form of chassis 31 in which, however, like parts are provided with like references. The chassis 31 has a base 32 with a column 33 fixed thereto. The base 32 has three wheels 34 for transverse displacement of the aligning apparatus 30 in front of the vehicle. The rotary knob 23 cooperates, through driving means (not shr n) inside the chassis 31, with a step-by ,tep switch in the base portion 35.The driving means and the switch are such that by rotating the rotary knob 23, the base portion 35 is sequentially raised from the floor, displaced in the direction of the arrow and lowered to the floor, thus rotating of the column 33 and with it the optical system support 14, relative to the floor. The method of aligning the apparatus 30 using the mirror 18 is in other respects the same as with the apparatus 10 shown in Figure 1.

Figure 3 shows a cross section through another form of reflecting element which, in this case, is provided as a prism 40. The surface 41 formed by the hypotenuse fulfills the function of the reflecting surface 19 of the mirror 18 shown in Figure 1. Each of the surfaces 42, 43 formed by the other sides of the prism carries a reference line 44, 45. The prism 40 is mounted in a plastics housing 46 and is pivotally mounted on an axis 47.

Modifications of the embodiments described above are, of course, possible without departing from the scope of the invention. Thus, the design of the mirror, of the optical system support or of the chassis can be varied without departing from the arrangement and position of the reflecting element which enable an ergonomically desirable adjustment of the apparatus for the purpose of accurate alignment with the vehicle to be effected.

WHAT WE CLAIM IS:- 1. Apparatus for testing the alignment of vehicle headlights, which comprises a chassis consisting of a base and a column, an optical system carrier mounted on the column, and an adjustable aligning device for aligning the apparatus with the motor vehicle to be tested, the aligning device comprising a single reflecting element bearing at least one reference line extending transversely with respect to the optical axis of the optical system and the reflecting element being pivotally mounted for rotation about an axis coincident with or parallel to the reference line, on an arm mounted near the upper end of the column.

2. Apparatus according to claim 1, in which the reflecting element is a longitudinally extending parallel-sided flat mirror and the reference line lies substantially on the longitudinal centre line of the mirror.

3. Apparatus according to claim 1 or 2, in which the optical system carrier is nonrotatable on the column but adjustable in height thereon and the column is provided

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. This rotary device is more fully described and claimed in our Application 37777/77 (Serial No. 1 571 225). Tbe arm 17 is preferably so dimensioned that it supports the mirror 18 at such a distance from the rotary knob 23, that the mirror is at or above eye level of an operator standing on the ground behind the apparatus (relative to the vehicle being tested) while it can be reached by the operator's hand. The rotary knob is also readily within reach of the operator. Thus, the mirror 18 and the rotary knob 23 can readily be adjusted simultaneously while the mirror is in the field of vision of the operator. The method of operation of the aligning apparatus 10 will now be described: the apparatus 10 is wheeled on the rails in front of the headlight of a vehicle to be tested and is then aligned laterally and vertically substantially with the optical axis thereof. By moving the arm 17 and the mirror 18, the operator then searches by eye for two definite points 24, 25 on the front bodywork of the motor vehicle so that these points 24, 25 coincide substantially with the reference line 22 on the reflecting surface 19. Then, by actuating the rotary knob 24, the mirror 18 together with the column 13 can be so rotated with reference to the base 12 that the two points 24, 25 exactly coincide with the reference line 22, whereupon the desired alignment of aligning apparatus 10 with respect to the vehicle is achieved.During this aligning procedure, the arm 17 only needs to be moved in the mounting 16 if another operator of a different height has previously used the apparatus 10. With the same operator, the arm is initially moved into such a position that the entire width of the vehicle can be seen in the mirror 18 and thus two points appropriate to one another can be aimed at. Thereafter, a slight movement of the mirror 18 about its axis is normally sufficient to bring the two points on to the reference line. The position of the mirror 18 relative to the aligning apparatus 10 is such that the operator can easily reach and move the mirror with one hand while maintaining his line of sight substantially horizontal. At the same time, the operator can easily reach the rotary knob 23 with his other hand and rotate it, this also being within his field of vision while looking at the mirror 18.Thus, it is of particular advantage that the manual actua tions are concentrated within a limited space which favours a simple, rapid and proper alignment because no foot movement is re quired which might interrupt concentration and which could lead to an undesired change in the position of the aligning apparatus 10. Figure 2 shows a second embodiment of aligning apparatus 30 which differs from that shown in Figure 1, chiefly in being a freely, mobile apparatus with another form of chassis 31 in which, however, like parts are provided with like references. The chassis 31 has a base 32 with a column 33 fixed thereto. The base 32 has three wheels 34 for transverse displacement of the aligning apparatus 30 in front of the vehicle. The rotary knob 23 cooperates, through driving means (not shr n) inside the chassis 31, with a step-by ,tep switch in the base portion 35.The driving means and the switch are such that by rotating the rotary knob 23, the base portion 35 is sequentially raised from the floor, displaced in the direction of the arrow and lowered to the floor, thus rotating of the column 33 and with it the optical system support 14, relative to the floor. The method of aligning the apparatus 30 using the mirror 18 is in other respects the same as with the apparatus 10 shown in Figure 1. Figure 3 shows a cross section through another form of reflecting element which, in this case, is provided as a prism 40. The surface 41 formed by the hypotenuse fulfills the function of the reflecting surface 19 of the mirror 18 shown in Figure 1. Each of the surfaces 42, 43 formed by the other sides of the prism carries a reference line 44, 45. The prism 40 is mounted in a plastics housing 46 and is pivotally mounted on an axis 47. Modifications of the embodiments described above are, of course, possible without departing from the scope of the invention. Thus, the design of the mirror, of the optical system support or of the chassis can be varied without departing from the arrangement and position of the reflecting element which enable an ergonomically desirable adjustment of the apparatus for the purpose of accurate alignment with the vehicle to be effected. WHAT WE CLAIM IS:-

1. Apparatus for testing the alignment of vehicle headlights, which comprises a chassis consisting of a base and a column, an optical system carrier mounted on the column, and an adjustable aligning device for aligning the apparatus with the motor vehicle to be tested, the aligning device comprising a single reflecting element bearing at least one reference line extending transversely with respect to the optical axis of the optical system and the reflecting element being pivotally mounted for rotation about an axis coincident with or parallel to the reference line, on an arm mounted near the upper end of the column.

with adjustment means which can be operated to rotate the column about its axis relative to the ground.

4. Apparatus according to claim 3, in which the base is adapted to travel on rails and the column is rotatable relative to the base, and the adjustment means is positioned at the top of the column and is in operative communication with rotating means inside the column which serve to rotate the column.

5. Apparatus according to any of claims 1 to 4, in which the reflecting element is positioned at or above the eye level of an operator standing upright on the ground, and at a level where it can be reached by the operator when so standing.

6. Apparatus for testing the alignment of vehicle headlights substantially as herein described with reference to any of Figures 1 to 3 of the accompanying drawings.