JPH0226755Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an optical axis adjustment device for a headlamp for an automobile.

Headlamps are required to illuminate the area in front of the vehicle, while at the same time not dazzling drivers of oncoming vehicles. Therefore, headlamps installed at the time of automobile assembly are aimed so that the optical axis is at an ideal position that is easy to drive and does not dazzle the driver of an oncoming vehicle. However, the optical axis of the headlamp changes depending on the vehicle loading conditions such as the number of passengers and cargo capacity, and as a result, the optical axis may point upward or downward from the aiming position, dazzling oncoming vehicles. It often becomes difficult to drive. Therefore, an optical axis adjusting device is provided for leveling the optical axis of the headlamp to return it to the aimed position.

However, conventional devices are generally leveling-only optical axis adjustment devices that are independent of the aiming device, so when installing it on a headlamp, the aiming device and optical axis adjustment device must be installed separately. The problem is that the number of parts increases because the connection must be made using a connecting mechanism.

In order to improve this point, a headlamp optical axis adjustment device having both an aiming function and a leveling function has been proposed (West German Patent Application No. 2952217).

However, in this device, when the motor is driven for leveling, the sleeve 21 moves in the axial direction, so the aiming adjustment screw 31
It also moves in the axial direction, and therefore requires an installation space corresponding to the amount of movement.

The present invention aims to improve these points and provide an optical axis adjustment device for a headlamp in which the aiming operation shaft does not move at all in the axial direction during aiming or leveling.

Hereinafter, the present invention will be described based on an embodiment of the accompanying drawings.

In FIG. 1, 1 is a headlamp. This headlamp 1 is a movable reflector type headlamp, as shown in Figs. 2 and 3.
A reflector 4 is supported by a lamp body 3 with a lens 2 disposed on the front. 5 is a bulb attached to the reflector 4; 6 is a rubber cover that covers the rear opening of the lamp body 3;
A is in close contact with the rubber cover 6 and exposed to the outside.

The reflector 4 is tiltably supported by the lamp body 3 at three points, one of which is a fulcrum mechanism 7. Of the other two points, one is the aiming device 10, and the other is the optical axis adjustment device 20, which has both an aiming mechanism and a leveling function. The fulcrum mechanism 7 is constructed by pivotally fitting a pivot shaft 8 fixed to the mounting piece 4a of the reflector 4 and a pivot holder 9 provided to the lamp body 3. The aiming device 10 is constructed by screwing together an adjusting screw 11 rotatably held in a fixed position on the lamp body 3 and a pivot ball 12a of a screw holder 12 provided on a mounting piece 4b of the reflector 4. As shown in FIG. 1, this aiming device 10 tilts the reflector 4 in the left-right direction. In addition, code 1
1a is the flange of the adjuster screw 11, and the flange 11a is connected to the holder 1 through the packing 13.
4 to the lamp body 3, the adjusting screw 11 is rotatably held in a fixed position. Further, the screw holder 12 and the pivot ball 12a are pivotally fitted together. The optical axis adjustment device 20 attached to the lamp body 3 is attached to the mounting piece 4c of the reflector 4.
The connecting rod 16 is pivotally fitted into the rod holder 15 provided in the
A head 30a provided at one end of the 0 is pivot-fitted and connected. Note that the present invention is not limited to this example, and the rod holder 15 and the head 30a may be directly connected by a pivot.

Next, the optical axis adjustment device 20 will be described.

As is clear from FIGS. 4 to 7, the optical axis adjustment device 20 of the present invention includes two housings 2.
In the room defined by 1 and 22, there is provided a motor 23, a hollow gear 27 which rotates via a deceleration mechanism 24 due to the rotation of the motor 23, and a hollow gear 27 which is threadedly engaged with the inner surface of the hollow gear 27 and is rotated by the rotation of the hollow gear 27. A cylindrical body 28 configured to move linearly without rotating,
A rod 30 is inserted and screwed into the cylindrical body 28 and has one end located outside the housing 21, and a rod 30 is rotatably held in a fixed position by the other housing 22 and has the other end located outside the housing 22. One end of the shaft 29 and the other end of the rod 30 are formed with a non-circular cross section and are slidably fitted together, and during aiming, the rod 30 and the shaft 29 rotate together. However, during leveling, the rod 30 slides against a shaft held in place. Therefore, when the aiming adjustment is performed when assembling the vehicle, when the shaft 29 protruding from the outside of the housing 22 is rotated by hand, the shaft 29 rotates in a fixed position, so that the rod 30 is fitted in a non-circular shape. Although the fixed position is about to rotate, since the cylindrical body 28 which is threadedly engaged with the rod 30 has a non-rotating configuration, only the rod 30 is threadedly engaged and rotated to move forward or backward linearly. Therefore, the amount of linear movement of the rod 30 changes the angle of the reflector 4, thereby changing the direction of the optical axis upward or downward.

In addition, the leveling adjustment that changes depending on the vehicle loading condition is performed when the hollow gear 27 is rotated by the motor 23 and the speed reduction mechanism 24. Since it is threadedly engaged with the inner surface of 27, it causes forward or backward linear movement in a non-rotating state. At this time,
Since the cylindrical body 28 is in a non-rotating state, it moves linearly together with the threaded rod 30. In this case, since the shaft 29 is held in place by the other housing 22 and cannot be moved, the rod 30 slides and moves linearly relative to the shaft 29. Therefore, the shaft 29 does not move, but the cylindrical body 28 moves linearly, and the amount of linear movement is transmitted to the reflector 4 via the rod 30, causing the angle of the reflector 4 to tilt upward or downward.

The details of the apparatus of the present invention having the above-mentioned configuration will be explained with reference to FIGS. 6 and 7.

The speed reduction mechanism 24 in this example is composed of a worm gear 25 and a wheel gear 26 provided on the shaft of the motor 23. The wheel gear 26 has a first gear part 26a on its outer surface that meshes with the worm gear 25, and a second gear part 26b having a smaller diameter than the first gear part 26a.
It is rotatably supported by 1a. hollow gear 27
The wheel gear 26 is attached to one end of the cylindrical body.
The first gear portion 27a meshes with the second gear portion 26b of
It has a thread groove 27b on the inner surface of the main body, and in this example, a second gear portion 27c having a smaller diameter than the first gear portion 27a is formed on the outer surface of the main body. and,
The hollow gear 27 is installed on one side of the housing 21.
A recess 21c provided around a through hole 21b formed in
One end of the hollow gear 27 is fitted into the housing 21, and the other end is fitted into a recess 31b provided around a through hole 31a formed in the base plate 31, so that the housing 21 and the base plate 31 are rotatably held. Note that the base plate 31 is held between the housing 21 on one side and the housing 22 on the other side.

The cylindrical body 28 has an outer surface having a non-circular cross section. In this example, a flat surface 28a is formed in a part of the outer surface in the longitudinal direction to form a non-circular shape with a substantially D-shaped cross section. And hollow gear 2 on the outer surface
An external thread groove 28b that screws into the thread groove 27b of No. 7 is formed, and an internal thread groove 28c is formed on the inner surface. This cylindrical body 28 is inserted and screwed into the hollow gear 27 and held therein, and one end of the cylindrical body 28 is fitted into the through hole 21b of one of the housings 21 so that it cannot rotate. That is, housing 2
The first through hole 21b has a substantially D-shaped cross section corresponding to the outer surface shape of the cylindrical body 28. Therefore, the through hole 21
The fitting between b and the cylinder body 28 makes the cylinder body 28 non-rotatable with respect to the rotation of the hollow gear 27, and since the cylinder body 28 is threadedly engaged with the inner surface of the hollow gear 27, the hollow gear 27
When the cylinder 28 is rotated, the cylindrical body 28 is moved only in a straight line in a non-rotating state.

The rod 30, which has a threaded groove 30b on its outer surface that engages with the internal threaded groove 28c of the cylinder 28, has a spherical head 30a at one end and an insertion hole 30c with a non-circular cross section at the other end. In this example, the cross-sectional shape of the insertion hole 30c is rectangular. The rod 30 is inserted and screwed into the cylindrical body 28 from the insertion hole 30c side and held by the cylindrical body 28, and the head 30a is located outside one of the housings 21. The shaft 29, which has a collar portion 29a formed approximately in the middle, has a fitting portion 29b formed at one end and a knob 32 at the other end. The insertion part 29b is the insertion hole 3
It has a non-circular cross section with a rectangular shape corresponding to 0c. Then, as shown in FIG.
2a, the fitting portion 29b is slidably fitted into the insertion hole 30c of the rod 30 through the circuit board 35 and the through hole 31a of the base. Further, the flange portion 29a of the shaft 29 is connected to the through hole 2 of the other housing 22.
By positioning the shaft holder 34 in the recess formed around the housing 2a and fixing the shaft holder 34 to the housing 22 with screws through the packing ring 33, the shaft 29 is rotatably held in a fixed position in the other housing 22. Note that at this time, the knob 32 is located outside the other housing 22. Therefore,
When you hold the knob 32 and rotate the shaft 29,
The rod 30 is screwed into the cylindrical body 28 and
Since it is held so that it cannot rotate, the cylindrical body 28 moves linearly. Furthermore, when the hollow gear 27 rotates, the cylindrical body 28 moves linearly, so the rod 3
0 slides on the shaft 29 in a non-rotating state and moves linearly. Note that the shapes of the insertion hole 30c and the fitting portion 29b are not limited to the above example, and may be any non-circular shape such as an oval cross section. Further, the cylinder 28 may be non-rotatably configured by the base plate 31 and the disclosed structure or a similar structure.

The optical axis adjustment device of the illustrated embodiment has a detection function for detecting the amount of movement of the rod 30 during leveling. The detection mechanism is a circuit board 35 shown in FIG.
and a terminal 36. The circuit board 35 is held between the base plate 31 and the other housing 22. terminal 36
As shown in FIGS. 8 and 9, the projection 36a
It has a contact piece 36b and a plurality of bent pieces 36c. The terminal 36 is a bent piece 36c.
The final gear 3 engages with the protrusions 37a formed in the same number as the
7, so that the contact pieces 36b are brought into pressure contact with the plurality of divided energization patterns 35a of the circuit board 35. Further, the protrusion 36a is adapted to come into contact with a circular current-carrying pattern 35b of the circuit board 35. On the back side of the circuit board 35, electronic components (not shown) with different set voltages are attached between the divided energizing pattern 35a and the circular energizing pattern 35b, and are electrically connected to a control circuit switch (not shown). It has been done. In addition, 36d in the figure is a hole formed in the bent piece 36c, and the hole 36d loosely fits into the protrusion 37a of the final gear 37, so that the terminal 36 can freely move between the final gear 37 and the circuit board 35. It is set as. Further, 40 is a spring interposed between the final gear 37 and the terminal 36.

The final gear 37 may be directly engaged with the hollow gear 27, but in this example, as shown in FIGS. 4 to 6, the final gear 37 is rotated at a reduced speed via two wheel gears 38 and 39. One wheel gear 38 is located coaxially with the final gear 37, and the wheel gear 38 is connected to the second gear portion 27c of the hollow gear 27.
a first gear portion 38a that meshes with the first gear portion 3;
8a, and a second gear portion 38b having a smaller diameter than 8a. The other wheel gear 39 is the same as the one wheel gear 3
The first gear part 39 that meshes with the second gear part 38b of No. 8
a, and a second gear portion 39b that meshes with the final gear 37.
It has And support columns 21d, 21e
Each gear 37, 38, 39 is supported by.

The headlamp is leveled as follows. That is, when a switch (not shown) installed in the driver's seat is operated and power is supplied to the motor 23, the divided conduction pattern 35a and the circular conduction pattern 35b of the circuit board 35 are connected to the contact piece 36b and the protrusion 36a of the terminal 36. The motor 23 is rotated by the connection. This causes the hollow gear 27 to rotate via the deceleration mechanism 24, and this rotation causes the cylinder 28 to move linearly along with the rod 30.

At this time, the hollow gear 27 causes the final gear 37 to rotate at a reduced speed via the two wheel gears 38 and 39. Then, the terminal 36 attached to the final gear 37 rotates and stops at a position designated by a switch (not shown) based on the energization pattern 35a, and the cylindrical body 28 also stops moving. If further adjustment of the angle of the optical axis is required, the switch on the driver's seat is operated again, and the angle of the optical axis is adjusted step by step by repeating the above-described operations. This is due to the difference in set voltage between each divided energization pattern 35a and the circular energization pattern 35b.

During leveling, it is sufficient to move the optical axis by the rod 30 in one step by a few millimeters, but detecting and controlling the position of several millimeters requires extremely precise control. In the above embodiment, the rotation of the terminal 36 is expanded to facilitate position detection.

The above embodiment was applied to a movable reflector type headlight, but
The optical axis adjustment device of the present invention can also be applied to a movable unit type headlamp.

As described above, according to the present invention, it has both the aiming function and the leveling function,
In particular, since the aiming shaft is held in a fixed position and does not move in the axial direction both during aiming and leveling, there is an effect that the installation space for the headlamp can be kept to a minimum.

[Brief explanation of the drawing]

The attached drawings show one embodiment of the present invention, and FIG. 1 is a front view of a headlamp to which the present invention is applied, FIG. 2 is a sectional view taken along the line -- in FIG. Figures 4 and 5 show the optical axis adjusting device.
FIG. 5 is a sectional view taken along the line - in FIG. FIG. 8 is an exploded perspective view of the detection mechanism, and FIG. 9 is a sectional view of the terminal. 1... Head lamp, 20... Optical axis adjustment device,
21, 22...housing, 23...motor,
24... Reduction mechanism, 27... Hollow gear, 28...
Cylindrical body, 29...shaft, 30...rod.

Claims (1)

[Scope of utility model registration request] This optical axis adjustment device adjusts the optical axis direction of a headlamp, and the optical axis adjustment device includes a motor and a hollow gear that rotates via a reduction mechanism due to the rotation of the motor, in a chamber defined by two housings. ,
A cylindrical body that is threadedly engaged with the inner surface of the hollow gear and supported so as to move linearly without rotating with respect to the rotation of the hollow gear, and a cylindrical body that is inserted and threadedly engaged with the cylindrical body and has one end located outside the one housing. a shaft rotatably held in place in the other housing, the other end of which is located outside the other housing, one end of the shaft and the other end of the rod having matable cross-sections; An optical axis adjustment device for a headlamp, characterized in that it is formed in a non-circular shape and is slidably fitted and connected so that the shaft does not move during aiming by rotating the shaft or leveling by driving a motor.