JPH0737405A - Lens drive mechanism of variable distribution lighting fixture for vehicle - Google Patents

Abstract

PURPOSE:To drive to control a movable lens as well as to make the structure simple and in a small size, by composing the system to sway and displace the movable lens in the direction of the optical axis making a rotating shaft on whose left side and right side edges the movable lens is composed, as a rotating center. CONSTITUTION:A movable lens 9 is swayed and displaced by driving to control an actuator 14, and the lens 9 is moved to a specific position to a fixed lens 6, so as to change over a front side radiating light flux to a 'focused radiating light' or a 'scattered radiating light'. That is, since a parallel light flux from a bulb 5 passing through the reflector surface of a reflector 2 is radiated from the rear side of the lenses 6 and 9, the light flux radiated in front of the lens 6 is focused or scattered by the relative relation of the focus position of a lens step 7 composed by both lenses. Furthermore, since the lens 9 is composed to be swayed and displayed in the direction of the optical axis making a rotating shaft 11 as the rotating center, the number of parts can be reduced, and the laterally separating phenomenon or a one side leaning of the light distribution pattern can be eliminated. Consequently, a small size can be realized as well as the structure can be simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp such as a fog lamp, in which the relative position of two lenses having a plurality of cylindrical lens steps is adjusted and displaced so that the light distribution pattern of the illuminating light flux can be adjusted according to the driving condition. The present invention relates to a lens drive mechanism of a variable light distribution type vehicular lamp which is configured to be capable of changing light concentration and diffusion.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6, a plurality of cylindrical lens steps 53 and 55 are arranged on the front optical axis L of a bulb 51 for a light source for emitting a parallel light beam.
The fixed lens 52 and the movable lens 54 having the
A variable light distribution type such as a fog lamp or a headlamp, in which an actuator 56 such as a step motor that changes the relative distance in the focal direction by displacing the movable lens 54 in the optical axis L direction (arrow A) between the two lenses 52 and 54 is used. A vehicular lamp 57 is known. Then, the movable lens 54 is displaced in the optical axis L direction (arrow A) with respect to the fixed lens 52 by the actuator 56, and the relative relationship between the focal positions of the lens steps 53 and 55 of both lenses 52 and 54 is changed.
The structure is such that the light flux emitted from the fixed lens 52 to the front is controlled to be condensed or diffused.

That is, the movable lens 54 of the variable light distribution type vehicular lamp 57 supports a movable lens holder 58 to which the movable lens 54 is attached via parallel links 60 formed on both left and right sides of a lamp body 59. Fixed lens 5
It is configured to be displaced in the direction of the optical axis L while maintaining the facing positional relationship parallel to 2. This parallel link 60
Are attached to the lower edges of the left and right sides of the lamp body 59, respectively.
A pair of equal-length link arms 62, which are rotatably erected via 1, 61, project rearward from the left and right sides of the movable lens holder 58 to the upper ends of the pair of equal-length link arms 62 so as to be orthogonal to the frame surface. Formed holder bracket 63, 63
The arm 6 rotatably attached to both end faces of the movable lens holder 58 via shafts 64 and 64 so that the link arms 62 and 62 are parallel to each other and connected to the lower edge of the movable lens holder 58.
The movable lens holder 58 can be displaced in the front-rear direction by the actuator 56 via the actuator 5.

[0004]

However, according to the conventional lens driving mechanism of the variable light distribution type vehicular lamp 57, the movable lens 54 is moved in the front-rear direction together with the movable lens holder 58. The link arms 62, 62 and the holder bracket 6363 that form the link 60,
Also, the number of mechanical parts such as the shafts 61 and 64 increases, the load applied to the actuator 56 increases, and the actuator 56 must be increased in size. Further, as shown in FIG. When changing the distance and changing the light distribution pattern of the irradiation light flux, there is no problem during focused irradiation (a), but there is a problem that lateral diffusion (b) occurs in the light distribution pattern during diffuse irradiation.

Further, the displacement of the movable lens 54 in the front-rear direction causes a large number of parts such as the parallel link 60 and the holder bracket 63 to intervene, and the movable lens 54 itself is movably supported by the parallel link 60. For,
It is difficult to improve the positional accuracy of the movable lens 54 with respect to the fixed lens 52 in the left-right direction, and when the movable lens 54 is driven to change the relative distance to the fixed lens 52, the lens steps 53 of both lenses 52, 54, 5
5 shifts in the left-right direction and shifts to one side of the light distribution pattern (see FIG.
(C)) is also likely to occur.

The present invention was devised in view of the above problems, and provides a lens driving mechanism for a variable light distribution type vehicular lamp that has a simple structure and a small size, and can control and drive a movable lens. The purpose is to do.

[0007]

To achieve the above object, a lens driving mechanism of a variable light distribution type vehicular lamp according to the present invention reflects light from a bulb arranged in front of a reflector to the reflector. In a vehicular lamp that irradiates a parallel light flux to the front of the lamp with a mirror surface, on the front optical axis of the bulb that radiates the parallel light flux, a fixed lens and a movable lens, each of which constitutes a cylindrical lens step extending in the longitudinal direction, are arranged. The movable lens is oscillated and displaced in the optical axis direction about a rotation axis formed on the left and right side edges of the movable lens, and the relative distance in the focal direction of each lens step formed on both lenses is changed to distribute the irradiation light flux. The gist is that it is configured so that the light can be changed.

[0008]

According to the above construction, the actuator is controlled and driven to oscillate and displace the movable lens, and the movable lens is moved to a predetermined position with respect to the fixed lens, so that the forward irradiation light beam is “converged irradiation light” or “diffuse irradiation”. Switch to "light". That is, since the parallel light flux from the bulb is emitted from the rear of the fixed lens and the movable lens through the reflecting mirror surface of the reflector,
Due to the relative relationship of the focal positions of the lens steps formed on both lenses, the light flux irradiating in front of the fixed lens converges or diffuses. Moreover, since the movable lens is constructed so that it can be oscillated and displaced in the optical axis direction about the rotation axis formed on the left and right side edges thereof, the number of parts can be reduced.
Moreover, the movable lens can be displaced to a preset position by an actuator, the lens interval of the rotating shaft portion is narrowed even during diffuse irradiation, and the light condensing portion remains in the center of the light distribution pattern, so the light distribution pattern Of the light distribution pattern does not occur in the horizontal direction with respect to the fixed lens when the movable lens is driven.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a lens driving mechanism of a variable light distribution type vehicular lamp according to the present invention will be described below with reference to the drawings. Figure 1
2 and FIG. 2 show a variable light distribution type vehicular lamp equipped with a lens driving mechanism, and a reference numeral 1 is a lamp in which a reflector 2 having a reflecting mirror surface 3 having an optical axis L is fixed to the rear end. A bulb 5 for a light source, which is a body and has a bulb base portion 4 locked to a rear portion of the reflector 2, is provided so as to be replaceable and substantially located at a focal point F of the reflecting mirror surface 3.

Further, as shown in FIG. 3, a fixed lens 6 is provided on the front side of the lamp body 1 in which a large number of cylindrical lens steps 7, 7 ... The fixed lens 6 is fixed to form a front lens of the lamp, and a movable lens 9 attached to a movable lens holder 8 having a substantially rectangular frame shape is provided on the back side of the fixed lens 6.
Are arranged in the movable lens 9, and a large number of cylindrical lens steps 10 extending in the vertical direction correspond to the lens steps 7 formed in the fixed lens 6 and are formed in parallel at equal pitches. There is.

In this embodiment, the lens step 7 of the fixed lens 6 is formed by a cylindrical plano-concave lens, and the lens step 10 of the movable lens 9 is formed by a cylindrical plano-convex lens, and the movable lens 9 is formed on the concave surface of the fixed lens 6.
It has a structure that the planes of are arranged so as to face each other.
It goes without saying that the combination of the shapes of the lens steps 7 and 10 is not necessarily limited to the combination of the plano-concave and plano-convex.

In the movable lens 9, the tip ends of rotating shafts 11, 11 projecting from the left and right side edges of the movable lens holder 8 to which the movable lens 9 is attached to the left and right sides are located on both upper sides of the lamp body 1. The bearings 12 and 12 are rotatably attached to the bearings 12 and 12 so that the bearings 12 and 12 are swingably displaced in the direction of the optical axis L while maintaining a parallel positional relationship with the fixed lens 6. The movable lens holder 8 has a structure in which a tip of a connecting rod 15 connected to an actuator 14 is fixed to a bracket 13 protruding rearward from a lower end portion thereof. Therefore, since the movable lens 9 is always supported by the bearings 12 and 12 formed in the lamp body 1 and swingably displaced, even when the movable lens 9 is swung with respect to the fixed lens 6, the fixed lens 9 is swung. There is no displacement in the left-right direction with respect to 6, and there is no deviation of the light distribution pattern.

FIGS. 4 (a) and 4 (b) show a light distribution pattern of the variable light distribution type vehicular lamp according to the present invention.
A state in which the actuator 14 of the lens driving mechanism configured as described above is controlled and driven, the rotation shafts 11 and 11 are set as rotation centers through the connecting rod 15, and a parallel facing positional relationship with the fixed lens 6 is maintained. The lower end side, that is, the swinging side is displaced rearward along the optical axis L, and the relative distance to the fixed lens 6 is changed so that the light distribution pattern of the front irradiation light flux of the bulb 5 is, for example, "condensed irradiation light" ( Switch to a) or "diffuse illumination" (b). Since the distance between the movable lens 9 and the fixed lens 6 due to the swing displacement of the movable lens 9 is gradually increased from the pivotal support side by the rotary shafts 11 to the swing side, both are supported. A preferable light distribution pattern can be obtained by the lens steps 7 and 10 of the lenses 6 and 9, and the occurrence of lateral cracking of the light distribution pattern can be prevented.

FIGS. 5 (a) to 5 (e) show another embodiment of the shaft supporting portion of the movable lens holder. In the lens driving mechanism according to the present invention, the shaft supporting portion of the movable lens holder 8 to which the movable lens 9 is attached (rotating shafts 11 and 11 constituent parts).
Is used to displace the swing side (the side driven by the actuator 14) forward or rearward (a) along the optical axis L, and the shaft support portion is not necessarily the upper part of the left and right side edges of the movable lens holder 8. It need not be formed on the side. That is, the rotating shafts 11 and 11 are formed at the lower ends of the left and right edges of the movable lens holder 8, the lower end side is the center of rotation, and the tip end of the connecting rod 15 of the actuator 14 is connected to the upper end side.
The swing side of the movable lens 9 may be displaced rearward (b) or forward (c). Further, the pivotal support portion of the movable lens holder 8 does not necessarily have to be the upper end portion or the lower end portion of the movable lens holder 8, and even if it is located slightly below the upper end portion (d), it is located slightly above the lower end. (E)
It may be a part that has been formed.

Needless to say, various actuators such as a rotary solenoid, a multi-position stop type thrust solenoid or a step motor can be used as the actuator 14 in each of the above embodiments. Further, the lens steps 7 and 10 formed on the fixed lens 6 and the movable lens 9 can be freely set in type and direction.

[0016]

Since the lens driving mechanism of the variable light distribution type vehicular lamp according to the present invention is configured as described above, the movable lens holder is moved along the optical axis by the actuator with the pivotal support portion for the lamp body as the center of rotation. By oscillating and displacing in the front-back direction, the separation relative distance of the movable lens to the fixed lens is gradually changed from the rotation axis side to the swing side to converge or diffuse the irradiation light beam, and The structure that the left and right cracks are prevented from occurring and the movable lens is always rotatably supported with respect to the lamp body, so a stable swing displacement operation of the movable lens can be obtained, and the movable lens is driven. It is possible to prevent the deviation of the light distribution pattern due to the positional shift in the left-right direction at the time. Further, according to the above configuration, the light distribution variable type vehicular lamp can be easily and robustly downsized, and the effect obtained by implementing the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a vehicular lamp showing an embodiment of a lens driving mechanism of a variable light distribution vehicular lamp according to the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is likewise a plan view of an essential part.

FIG. 4 is a diagram showing a light distribution pattern, showing condensed irradiation light (a) and diffuse irradiation light (b).

5A to 5E are explanatory views showing another embodiment of the mounting means for the movable lens holder and the shaft supporting portion.

FIG. 6 is a longitudinal sectional view showing a lens driving mechanism of a conventional light distribution variable type vehicle lamp.

FIG. 7 is a diagram showing a light distribution pattern by a lens driving mechanism of a conventional variable light distribution type vehicular lamp, showing condensed irradiation light (a) and diffuse irradiation lights (b) and (c).

[Explanation of symbols]

 1 Lamp body 2 Reflector 3 Reflective mirror surface 5 Bulb 6 Fixed lens 7 Lens step 8 Movable lens holder 9 Movable lens 10 Lens step 11 Rotating shaft 12 Bearing 14 Actuator 15 Connecting rod

Claims (1)

[Claims] 1. A vehicular lamp that irradiates light from a bulb disposed in front of a reflector as a parallel light flux toward the front of the lamp by a reflecting mirror surface of the reflector, on a front optical axis of the bulb that radiates a parallel light flux, A fixed lens and a movable lens, each of which constitutes a cylindrical lens step extending in the vertical direction, are arranged, and the movable lens is oscillated and displaced in the optical axis direction about a rotation axis formed on the left and right side edges of the movable lens. A lens driving mechanism for a variable light distribution vehicle lamp, characterized in that the light distribution of an irradiation light beam can be changed by changing the relative distance in the focal direction of each lens step formed on a lens.