JPH0226086Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for adjusting the optical axis direction of a vehicle headlamp.

[Conventional technology]

Vehicle headlamps are used by being attached to the vehicle body, and are required to illuminate the road ahead of the vehicle without dazzling oncoming vehicles when driving at night. For this reason, when a headlamp is assembled to a vehicle body at a vehicle manufacturing factory or maintenance shop, initial adjustment (aiming) of the optical axis direction is performed to comply with regulations.

However, even when aiming is performed as described above, the amount of deflection of the suspension spring changes due to changes in the number of passengers or the amount of cargo load, and the direction of the optical axis may be deviated. For this reason, an optical axis adjustment device is provided so that the direction of the optical axis of the headlamp can be adjusted (leveled) from the driver's seat.

As the optical axis adjustment device for leveling described above, the technique described in, for example, Japanese Utility Model Application No. 59-16242 is publicly known.

Conventional headlamp optical axis adjustment devices, including the above-mentioned known example, generally support the lamp housing or reflector of the headlamp in a tiltable manner, and transmit the rotational output of a DC motor to the lamp housing or the reflector through a group of reduction gears. This structure transmits power to the reflector and causes it to tilt.

[The problem that the idea aims to solve]

The above motor uses electromagnetic attraction and repulsion to move the rotor at high speed (at least several hundred rpm).
A DC motor is used that rotates the motor.

However, the headlamp optical axis adjustment device having the conventional structure as described above (a) has a complicated structure, is large in size, and has a large weight because it is provided with a DC motor and a reduction gear means.

(b) Electrical noise is generated from the motor brushes.

(c) Optical axis adjustment accuracy is adversely affected due to the large inertia of high-speed rotating members.

There is a problem.

The present invention improves the problems of the prior art as described above, and provides a headlamp light that does not have the risk of generating electrical noise, allows the direction of the optical axis to be adjusted freely with high precision, and can be configured to be compact and lightweight. It is an object of the present invention to provide an axis adjustment device.

[Means to solve the problem]

In order to achieve the above object, the present invention supports either the lamp housing of the headlamp or the reflector of the headlamp so as to be freely tiltable, and the tilting of either the lamp housing or the reflector is controlled by electric driving means. In the optical axis adjusting device for a headlamp, the electric drive means is a surface wave motor, and the rotor of the surface wave motor is cylindrical, and the inner surface thereof is cylindrical. A groove parallel to the axis is provided in the case, and a tubular screw is screwed into the case, and a protrusion is provided on the tubular screw, and the protrusion is slidably engaged with a groove provided in the rotor of the surface wave motor. and a driving rod is rotatably attached to the tubular screw, and the driving rod is coupled to the tilting feed screw of the lamp housing or the reflector.

The above-mentioned surface wave motor is a motor that was developed relatively recently with advances in semiconductor technology, and has the characteristics of lower speed and higher torque than conventional motors that utilize electromagnetic attraction and repulsion. There is. One of its features is that it does not require a reduction gear because of its low speed and large torque. It also has the following features: it does not generate electrical noise because it does not have brushes, and it is small and lightweight because it does not have a magnetically conductive core.

FIG. 4 is a sectional view showing a basic example of a surface wave motor, which includes an annular elastic ring (made of metal) 2 to which an annular piezoelectric element 1 is fixed, and an annular slider (made of rubber) 3.
The annular rotor 4, which is bonded to the rotor 4, faces and is in contact with the annular rotor 4.

As shown in FIG. 5, the surface of the piezoelectric element 1 is divided in the circumferential direction, and electrodes A and B are provided symmetrically facing each other, and a ground electrode E is provided in between.

A sine wave voltage is applied from the inverter to the above electrode A.
V ₀ sinωt and 90 for electrode B
Give a cosine wave voltage V ₀ cosωt with a phase difference of degrees. Then, a traveling wave is generated in the elastic ring 2 due to bending vibration, and the rotor 4 is driven in the opposite direction to the traveling wave.

When the voltage waveforms applied to electrodes A and B are reversed by the polarity changeover switch 5, the rotation direction of the rotor 4 is reversed.

[Effect]

As mentioned above, the present invention makes the rotor of a surface wave motor cylindrical, provides a groove parallel to the axis on its inner surface, and also screws a tubular screw into the case and provides a protrusion on the tubular screw. The protrusion is slidably engaged with the groove provided in the rotor of the surface wave motor, so that when the surface wave motor is driven and the rotor rotates, the engagement between the groove and the protrusion causes the tubular screw to rotate. The tubular screw moves back and forth in the axial direction to adjust the optical axis. The drive rod is rotatably attached to the tubular screw, and the drive rod is connected to the tilting feed screw of the lamp housing or reflector, so when the drive rod is rotated manually, it tilts independently of the tubular screw. The optical axis can be adjusted without using the surface wave motor by rotating the feed screw.

〔Example〕

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 is a sectional view of a headlamp equipped with an embodiment of the optical axis adjusting device of the present invention.

6 is a lamp housing, and 7 is a front lens. A reflector 9 is tiltably supported in the lamp housing 6 via a bracket 8. 10 is a ball joint which is a tilting fulcrum.

A nut member 11 is attached to the bracket 8, and a feed screw 12 is screwed together. The above feed screw 12 is
It is connected via a universal joint 13 to a drive rod 14 of a drive section.

An enlarged detail of the drive section is shown in FIG. 2, and an exploded perspective view thereof is shown in FIG. 3.

Reference numeral 15 denotes a cylindrical case with a bottom, and a female screw hole 15a is provided in the center of the bottom surface.

The tubular screw 16 is screwed into the screw hole 15a, and the small diameter portion of the drive rod 14 is inserted into the tubular screw 16.
Insert it into the hole, and use push nut 17 to prevent it from coming off.

Reference numeral 18 denotes a base plate configured in the shape of a lid of the cylindrical case 15.

A surface wave motor is housed in a space surrounded by the case 15 and the base plate 18. That is, the terminals 19A, 19B,
19E is attached, and the piezoelectric element 1' is fixed via the spacer 20. 2' is an elastic ring fixed to the piezoelectric element 1'.

On the other hand, the rotor 4' to which the slider 3' is fixed is rotatably fitted into the case 15.

The rotor 4' has a cylindrical shape, and a groove 4a parallel to the axis is provided on its inner surface. On the other hand, the tubular screw 16 is provided with a protrusion 16a, and the protrusion 16a is slidably engaged with the groove 4a. Reference numeral 21 denotes a disc spring that applies pressure to the elastic ring 2' and the slider 3'.

With the above configuration, terminals 19A and 19B
When a wave voltage of V ₀ sin ωt and V ₀ cos ωt is applied between 19E and 19E, the rotor 4' rotates, and the grooves 4a,
The tubular screw 16 is rotated via the protrusion 16a.
This tubular screw 16 is a female screw hole 15a of the case 15.
Since the screw is screwed into the nut member 11, the screw is fed in the left-right direction in the figure as it rotates, and this left-right movement is transmitted to the feed screw 12 (see FIG. Tilt 8.

When the waveform voltages of the terminals 19A and 19B are switched by a polarity changeover switch (see FIG. 5), the direction of rotation of the rotor 4' is reversed. In this way, the bracket 8 and the reflector 9 fixed thereto are freely tilted back and forth around the ball joint 10, and the optical axis direction of the reflector 9 changes accordingly.

Further, a square hole 14a is provided at the rear end (right end in FIG. 2) of the drive rod 14, into which the square column portion 22a of the manual operation rod 22 is slidably fitted. 23 is a retaining member, and 22b is a cross driver groove for operation. With this configuration, the optical axis can be adjusted without using the surface wave motor by engaging the cross driver in the cross driver groove 22b and rotating the drive rod 14. (In this case, the drive rod 14 idles relative to the tubular screw 16).

With this configuration, both leveling operation by remote operation using a surface wave motor and aiming operation by manual operation using a screwdriver can be performed.
This is convenient because it can be done arbitrarily and freely.

The optical axis adjustment device of the present invention configured as described above does not have a brush like a normal DC motor, so there is no risk of generating an electric nozzle.

Furthermore, since there is no member that rotates at high speed and the inertia of the rotating member is small, starting and stopping can be performed instantaneously, and the optical axis direction can be adjusted with high precision. Furthermore, since there is no need to provide a speed reducer, the structure can be made small and lightweight, and noise caused by the speed reducer is not generated.

[Effect of idea]

As mentioned above, the optical axis adjustment device of the present invention is
There is no risk of generating electrical noise, the optical axis direction can be adjusted freely with high precision, and it is compact.
It has an excellent practical effect of being lightweight.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a headlamp equipped with an embodiment of the optical axis adjusting device of the present invention. Figure 2 is the first
FIG. 3 is an enlarged detailed sectional view of the part shown in the figure, and is also an exploded perspective view. FIG. 4 is a schematic sectional view for explaining the surface wave motor, and FIG. 5 is a wiring diagram for explaining the usage and operation of the surface wave motor. 1, 1'... Piezoelectric element, 2, 2'... Elastic ring, 3, 3'... Slider, 4, 4'... Rotor,
4a... Groove, 6... Lamp housing, 8... Bracket, 9... Reflector, 11... Nut member, 12... Feed screw, 13... Universal joint, 14
... Drive rod, 14a ... Square hole, 15 ... Case,
16... Tubular screw, 16a... Protrusion, 20... Spacer, 21... Belleville spring, 22... Manual operation rod,
22a...Prismatic portion, 22b...Cross driver groove.

Claims (1)

[Scope of utility model registration request] A lamp for a headlamp, which is configured to tiltably support either the lamp housing of the headlamp or the reflector of the headlamp, and to drive the tilting of either the lamp housing or the reflector by an electric drive means. In the optical axis adjustment device, the electric drive means is a surface wave motor, and the rotor of the surface wave motor is cylindrical, and a groove parallel to the axis is provided on the inner surface of the motor. At the same time as screwing a tubular screw into the tubular screw, a protrusion is provided on the tubular screw,
The protrusion is slidably engaged with a groove provided in the rotor of the surface wave motor, and a drive rod is rotatably attached to the tubular screw, and the drive rod is used as a feed for tilting the lamp housing or reflector. A headlamp optical axis adjustment device characterized by being combined with a screw.