JPH0736305U - Shade drive mechanism of variable light distribution headlight - Google Patents

Abstract

(57) [Summary] [Purpose] With a simple configuration, the shade is moved smoothly up and down with respect to the optical axis to switch the light distribution pattern up and down, and the cutoff line is clarified. A front lens such as a collimator lens 4 is arranged on the front optical axis of a reflector 1 having an elliptical reflecting mirror surface 2, and a bulb 3 is arranged on the front optical axis of the reflector, and the bulb 3 and the front lens 4 are arranged. The projector-type variable light distribution headlamp is provided with a shade 5 for blocking a part of a light beam between them. The support base 8 supporting the shade 5 is constantly urged by the elastic member 10 so as to be pulled downward, and the support base 8 is pushed up to a predetermined height position by an elevating device such as an eccentric cam 12 and pulled down. To move the light distribution up and down, which is necessary to drive the vehicle.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a vehicular lamp, and more particularly to a shade drive mechanism of a variable light distribution type headlight that slides and displaces the shade up and down to change the light distribution required for traveling of the vehicle. is there.

[0002]

[Prior art]

 Conventionally, there have been automotive lamps that change the light distribution of the emitted light beam in accordance with the rotation angle of the steering wheel. Among these types of lamps, a headlamp constructed by displacing the shade to move the cut-off line of the light distribution pattern up and down includes a collimator lens on the front surface of the reflector 50 as shown in FIGS. 5 and 6. 51 is provided, a rotating shaft is eccentrically provided between the bulb 52 serving as a light source and the collimator lens 51, and a cylindrical shade 53 having a stepped portion is horizontally installed so that the shade 53 is used as a motor or the like. There is a structure in which the irradiation direction of the light distribution pattern is changed by rotating the drive mechanism 54 to rotate it in a direction orthogonal to the optical axis L, that is, rotating the shade 53 in the vertical direction (arrow X direction). .

Further, as shown in FIGS. 7 and 8, a rack 56 is provided, in which a shade 55 having an arc-shaped plane shape, which is arranged at the focal plane of the collimator lens 51, is provided in the lower part thereof in the vertical direction. With respect to the pinion 57, the shade 55 is moved up and down (in the direction of the arrow Y) by the drive mechanism 54 such as a motor to displace the shade 55 in a direction perpendicular to the optical axis L, thereby changing the light distribution pattern of the irradiation light beam in the vertical direction. There is also a structure that displaces to.

[0004]

[Problems to be solved by the device]

 Therefore, in this type of variable light distribution headlight, as shown in FIG. 9, the light distribution pattern a of the light flux is up and down (see the broken line b) or left and right (see the chain double-dashed line c) depending on the positions of the shades 53 and 55. It is designed to move in parallel to obtain the pattern required for the running of the vehicle. However, according to the configuration using the conventional cylindrical shade 53 as described above, since the shade 53 is linear, both sides of the shade 53 are located at positions away from the focal plane of the collimator lens 51. Therefore, there is a problem that the cut-off line of the light distribution pattern of the irradiation light flux is blurred on both sides.

In order to prevent the occurrence of blurring on both sides of the cutoff line, the shade 55 as shown in FIG. 7 is added to the focal plane of the collimator lens 51, and the planar shape is an arc shape. In the variable light distribution type headlamp formed in this way, the meshing state of the rack 56 and the pinion 57 becomes poor due to the vibration while the vehicle is running, and the smooth movement of the shade 55 becomes impossible. It had drawbacks.

The present invention has been made in view of the above problems, and in a lamp that changes the light distribution of an irradiation light beam by vertically displacing a shade provided in the lamp, the lamp has a simple structure. A more favorable light distribution can be obtained by changing the shape of the light pattern itself, and a light distribution variable front that can obtain a light distribution pattern with a clear cut-off line by smoothly pushing up or down the shade above and below. It is intended to provide a shade driving mechanism for a light.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, a shade driving mechanism for a variable light distribution headlamp according to the present invention has a front lens such as a collimator lens arranged on the front optical axis of a reflector having an elliptical reflecting mirror surface. In a projector-type variable light distribution headlamp, which comprises a shade fixed to the front optical axis of the reflector and blocking a part of the luminous flux between the bulb and the front lens, the shade is elastic. The member is always urged to pull down, and the eccentric cam structure inside the support platform pushes the shade upward to a predetermined height to obtain the light distribution required for vehicle running. This is the summary.

[0008]

According to the above configuration, the shape of the light distribution pattern itself can be formed by a shade that can change and adjust a part of the reflected light beam from the reflector to a desired height position. By freely switching and adjusting the range and height of the light distribution pattern of the irradiation light flux in accordance with the driving conditions of the automobile, that is, the rotation angle of the steering wheel, etc., the preferable light distribution required for driving the vehicle can be obtained. Further, the shade is always urged downward by an elastic member, and can be appropriately raised from below to above by a pushing member such as an eccentric cam or a connecting rod formed inside the support base. Therefore, the shade can be smoothly moved up and down.

[0009]

【Example】

 An embodiment of a shade driving mechanism of a variable light distribution type headlamp according to the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention, in which 1 is a reflector having an elliptical reflecting mirror surface 2 having a first focal point F1 and a second focal point F2 on an optical axis L. Is. A bulb 3 serving as a light source is arranged at the position of the first focal point F1 of the reflector 1, and a collimator lens 4 is provided on the front optical axis L of the reflector 1 to share the focal point with the second focal point F2 of the reflector 1. Is.

Reference numeral 5 is a shade having a planar shape which is on the optical axis L and is curved in an arc along the focal plane of the collimator lens 4. The shade 5 is fixed to a shade driving mechanism 7 mounted on a base 6 integrated with a lamp body (not shown) on the collimator lens 4 side so that the horizontal line and the vertical line coincide with the optical axis L of the lamp. It is a thing.

That is, the shade 5 is erected on the upper surface of a cylindrical support base 8 having a vertical cross-section that is open at the lower end side and has an inverted U-shape. This support base 8 is fixed on a lamp body (not shown), and is structured to be supported between support frames 9 that sandwich at least the front and rear surfaces of the support base 8 and guide sliding in the vertical direction. There is. The support base 8 has an elastic member 10 such as a coil bar or rubber for urging the support base 8 always pulled downward between the lower end portion 8a and the base 6 thereof, and is internally rotatable. An eccentric cam 12 rotatably supported by a shaft 11 is laterally pivotally mounted, and an outer peripheral cam surface of the eccentric cam 12 is always in contact with a lower surface of the support base 8. A drive mechanism 14 such as a motor is connected to the rotary shaft 11 via an intermediate gear 13, and the drive mechanism 14 is controlled and driven to rotate or rotate the eccentric cam 12 (direction of arrow X). The support base 8 is smoothly pushed upward against the biasing force of the elastic member 10, and the support base 8 is pulled down by the biasing force of the elastic member 10 (direction of arrow Y). The shade 5 is displaced with respect to the optical axis L within a predetermined vertical stroke range by the vertical movement of the support base 8. Reference numeral 15 is a potentiometer for detecting the vertical displacement position of the shade 5, and the above-mentioned driving is performed by the detection signal from the potentiometer 15 by presetting the relationship between the eccentric cam 12 and the steering mechanism of the vehicle such as steering. The mechanism 14 can be controllably driven by a central control circuit (not shown). In addition, the shade drive mechanism 7 according to the present invention is configured so that the drive can be manually controlled by "ON" or "OFF" operation of a switch (not shown) provided near the driver's seat of the vehicle. You can also

The shade drive mechanism 7 of the variable light distribution type headlamp configured as described above corresponds to the rotation angle of the steering, or if desired, the shade 5 is moved up and down by manual operation to distribute the light distribution pattern. Is vertically displaced in a direction orthogonal to the optical axis L to prevent the driver of an oncoming vehicle from being dazzled and to improve road visibility in the turning direction of the vehicle.

FIG. 4 shows a second embodiment of the shade driving mechanism of the present invention. In this embodiment, instead of the eccentric cam 12, one end 16a of the connecting rod 16 is swingably connected to the lower surface of the supporting base 8, and the other end 16b of the connecting rod 16 is located below the supporting base 8. Is connected to the end face of the rotating plate 17 arranged rotatably and eccentrically from the position of the rotating shaft 18, and the rotating plate 17 is rotated or rotated by a drive mechanism such as a motor (direction of arrow X). ) And the connecting rod 16 is moved up and down (in the direction of arrow Z) to smoothly raise or lower the support base 8 together with the shade 5 (in the direction of arrow Y) as in the first embodiment. It is configured to obtain. It should be noted that a drive mechanism such as a solenoid may be used instead of the elevating mechanism using such a connecting rod 16.

[0014]

[Effect of device]

 Since the shade drive mechanism of the variable light distribution headlamp according to the present invention is configured as described above, a part of the light flux is cut by the vertical movement of the shade to obtain a preferable light distribution pattern suitable for the running condition of the vehicle. While being formed, the irradiation direction of the light distribution pattern can be switched up and down by moving the shade up and down with respect to the optical axis as needed.

Moreover, since the shade is always urged downward by the elastic member together with the support base, and the direction of the urging force of the elastic member is vertically changed and adjusted by the rotating member such as the eccentric cam, the shade is supported. Provides a highly reliable shade drive mechanism that allows the support base to slide smoothly up and down with respect to the frame, and prevents problems such as positional displacement and failure during vehicle travel from occurring. The present invention has the feature that it can be performed, and the effect obtained by implementing the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view of essential parts showing a first embodiment of a variable light distribution type headlamp which constitutes a shade driving mechanism according to the present invention.

FIG. 2 is likewise a side sectional view of an essential part.

FIG. 3 is an enlarged vertical sectional view showing the shade driving mechanism.

FIG. 4 is a sectional view of an essential part showing a second embodiment of the shade driving mechanism.

FIG. 5 is a plan view of a variable light distribution type headlamp which constitutes a conventional tubular shade drive mechanism.

FIG. 6 is a side view of the same.

FIG. 7 is a perspective view showing a main part of a variable light distribution type headlamp having a conventional shade having an arcuate planar shape.

FIG. 8 is likewise a side sectional view of an essential part.

9A and 9B show changes in the irradiation direction of a light distribution pattern, where FIG. 9A is a downward light distribution pattern position when traveling straight ahead, FIG. 9B is also an upward light distribution pattern position, and FIG.
FIG. 6 is an explanatory diagram showing a light distribution pattern position in a state where the irradiation direction is displaced corresponding to the right turn of the vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reflector 2 Elliptical reflecting mirror surface 3 Valve 4 Collimator lens 5 Shade 7 Shade drive mechanism 8 Support base 9 Support frame 10 Elastic member 11 Rotating shaft 12 Eccentric cam 14 Drive mechanism (motor)

Claims (1)

[Scope of utility model registration request] 1. A front lens such as a collimator lens is arranged on the front optical axis of a reflector having an elliptical reflecting mirror surface, and a bulb is fixedly installed on the front optical axis of the reflector, and a light flux is provided between the bulb and the front lens. In a projector-type variable light distribution headlamp having a shade that blocks a part of the shade, the shade is urged by an elastic member so as to be constantly pulled downward, and the shade is arranged inside a support base. A shade drive mechanism for a variable light distribution type headlight, characterized in that it is configured to be pushed up to a predetermined height by an eccentric cam structure so as to obtain a light distribution necessary for traveling of a vehicle.