JP2012151058A - Shade driving unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a feeling of strangeness given to a user at switching of a light distribution pattern in a vehicular headlight forming a light distribution pattern through combination of movable shades and lighting on and off of a light source.SOLUTION: The shades 12A, 12B can switch a distribution pattern by moving between a shading position for shading part of light emitted from light sources 14a, 14b, and can adjust light intensity and an escaping position not shading. A moving mechanism 18 is connected to the shades 12A, 12B to be moved to either the shading position or the escaping position. A control part 228 controls the moving mechanism 18 so that the duration from start of lighting to completion of lighting of the light sources 14a, 14b, and the duration which the shades 12A, 12B completely move from the shading position to the escaping position are to be nearly the same.

Description

  The present invention relates to a shade driving unit that moves a movable shade in a vehicular lamp.

  Conventionally, there is a variable-light-distribution type vehicle headlamp device that forms a low-beam light distribution pattern by shielding light from a light source with a shade and forms a high-beam light distribution pattern when not shaded by a shade. Further, with the recent improvement in performance of vehicles, a headlamp device has been proposed in which the headlamp forms a light distribution pattern having a shape different from that of a standard low beam or high beam according to the surrounding conditions. In particular, in the case of a high beam, it is necessary to consider glare for oncoming vehicles and pedestrians while improving the driver's visibility. For example, in Patent Document 1, a vehicle headlamp capable of forming various light distribution patterns by combining turning on / off control of a light source and a plurality of movable shades that move between a light shielding position and a non-light shielding position. An apparatus is disclosed.

Japanese Patent Application No. 2010-131712

  However, in the vehicle headlamp device described in Patent Document 1, the light source is turned on and off and the movable shade is operated instantaneously at the time of switching the light distribution pattern. Therefore, the driver of the own vehicle may be uncomfortable.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a vehicle headlamp that forms a light distribution pattern by combining a movable shade and turning on and off of a light source. The purpose is to provide a technique for reducing the feeling of discomfort.

  In order to solve the above-described problems, a shade drive unit according to an aspect of the present invention is a shade drive unit for a vehicular lamp, and shields a part of light emitted from a light source whose light intensity can be adjusted. A shade that can be switched between a light distribution pattern by moving between a position and a retreat position that is not light-shielded, a moving mechanism that is connected to the shade and moves to either the light-shielding position or the retreat position, and lighting of the light source starts And a controller that controls the moving mechanism so that the time from when the lamp is fully lit until the time when the shade is completely moved from the light shielding position to the retracted position is substantially the same.

  According to this aspect, when the light source is turned on, the light intensity change of the light source and the movement of the shade are controlled to increase gradually rather than instantaneously, so that the light intensity in the vicinity of the shade also gradually changes. Therefore, it is possible to reduce the uncomfortable feeling given to the driver due to a rapid change in illuminance when the light distribution pattern is switched.

  The control unit may control the moving mechanism so that the time ratio of the light intensity increase of the light source and the time ratio of the light shielding range decrease due to the shade are substantially matched. According to this, the illuminance change observed by the driver becomes a constant ratio, and the uncomfortable feeling is further reduced.

  The control unit may control the moving mechanism so that the time from when the light source is fully turned on to when the light source is turned off substantially matches the time until the shade is completely moved from the retracted position to the light shielding position. According to this, even when the light source is turned off, the change in illuminance observed by the driver can be reduced, and the uncomfortable feeling can be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the discomfort given to a user at the time of switching of a light distribution pattern can be reduced in the vehicle headlamp which forms a light distribution pattern combining a movable shade and turning on and off of a light source.

It is a schematic sectional drawing explaining the internal structure of the vehicle headlamp apparatus. It is explanatory drawing explaining the light distribution pattern formed with the 1st light source of an optical unit, and a 2nd light source. It is explanatory drawing explaining an example of the light distribution pattern which can be formed with an optical unit. It is a figure explaining a mode that a control part controls a light source and a movable shade according to one embodiment of the present invention.

  FIG. 1 is a schematic cross-sectional view illustrating the internal structure of a vehicle headlamp device 210 on which the optical unit 10 of this embodiment is mounted. The vehicle headlamp device 210 is a high beam headlamp that is arranged one by one on the left and right in the vehicle width direction of the vehicle. Since the structure is substantially the same on the left and right, the vehicle is typically arranged on the right side of the vehicle. The structure of the headlamp device 210R will be described. The high beam vehicular headlamp device 210 has a light distribution pattern for the high beam as a whole by superimposing the light distribution pattern on the low beam formed by the separately disposed low beam vehicular headlamp device. Form.

  The vehicle headlamp device 210R includes a lamp body 212 and a transparent cover 214. The lamp body 212 has an opening in the front direction of the vehicle, and has a detachable cover 212a to be removed during maintenance on the rear side. A transparent cover 214 is connected to the opening in front of the lamp body 212 to form a lamp chamber 216. The lamp chamber 216 houses the optical unit 10 that irradiates light in the forward direction of the vehicle.

  On the inner wall surface of the lamp chamber 216, for example, at a position below the optical unit 10, a control unit 228 that performs turning on / off control of the optical unit 10 and light distribution pattern formation control is disposed. The control unit 228 may be provided in addition to the vehicle headlamp device 210R. Moreover, it is good also as only the function to relay control, such as turning on and off from the vehicle side.

  The optical unit 10 includes two types of shades (a first shade 12A and a second shade 12B described later), a moving mechanism 18, a light source 14, and a lamp housing 17 that supports the reflector 16 on the inner wall, and a projection lens 20. In the present embodiment, an example in which the light source 14 is configured by an LED array is shown, but other than that, for example, an incandescent bulb, a halogen lamp, a discharge bulb, an LED, or the like can be used. The reflector 16 reflects light emitted from the light source 14. Then, the light reflected by the reflector 16 is guided to the projection lens 20. The optical unit 10 of the present embodiment includes a light source 14a as a first light source and a light source 14b as a second light source in the vehicle width direction W, as shown in FIG. . In addition, dedicated reflectors 16a and 16b are disposed corresponding to the light sources 14a and 14b, respectively, and guide light from the light sources 14a and 14b in predetermined directions. Furthermore, in the case of the present embodiment, a plurality of first shades 12A are arranged so as to be adjacent to each other in the vehicle width direction W. FIG. 2 shows an example in which a first shade 12A1 that mainly shields light from the light source 14a and a first shade 12A2 that mainly shields light from the light source 14b are arranged. In the following description, the first shades 12A1 and 12A2 are referred to as the first shade 12A when it is not necessary to distinguish between them. Similarly, the light sources 14a and 14b are expressed as the light source 14 and the reflectors 16a and 16b are expressed as the reflector 16 unless it is necessary to distinguish between them.

  The first shade 12 </ b> A and the second shade 12 </ b> B are rotational axes that are movable between a position where light from the light source 14 toward the projection lens 20 is shielded (hereinafter referred to as an advance position) and a position where light is not shielded (hereinafter referred to as a retracted position). It is comprised so that it may rotate centering on 18a. FIG. 1 shows a state where the first shade 12A and the second shade 12B are moved to the advanced position. The moving mechanism 18 includes an actuator that rotates the first shade 12A. The first shade 12 </ b> A <b> 1 and the first shade 12 </ b> A <b> 2 can be independently moved to an advanced position (also referred to as a light shielding position) and a retracted position by the operation of the moving mechanism 18. Further, the second shade 12B is engaged with at least one end of the first shade 12A1 or the first shade 12A2 in the vehicle width direction W, and is driven by the engaged first shade to be in the advanced position and the retracted position. To move.

  Further, the first shade 12A is provided with a biasing member that returns to a predetermined posture, for example, a retracted position when the actuator is in a non-driven state. The biasing member can be constituted by, for example, a coil spring or a torsion spring. With such a configuration, even when the moving mechanism 18 fails, the presence / absence of high beam irradiation can be controlled by turning on and off the light source 14. That is, it is possible to avoid a situation in which the high beam light distribution pattern cannot be used. Further, when the moving mechanism 18 is brought into the non-driven state due to a failure or the like, the light source 14 can be turned off to shift to the low beam irradiation state, so that a fail safe function can be realized. The second shade 12B is a shade that follows the movement operation of the first shade 12A. For example, only the urging member for returning to the retracted position is connected, and the actuator for moving to the advanced position is not connected. . Therefore, if the first shade 12A moves to the advanced position, the second shade 12B also moves to the advanced position. If the first shade 12A moves to the retracted position, the second shade 12B also moves to the retracted position.

  FIG. 2 is an explanatory diagram for explaining a light distribution pattern formed by the light sources 14a and 14b of the optical unit of the present embodiment. As shown in FIG. 2A, the optical unit 10 of this embodiment includes two light sources 14. The light source 14a can irradiate light forward of the vehicle through the projection lens 20, and can form a long and narrow first irradiation region 100a extending in the vehicle width direction W as shown in FIG. Similarly, the other light source 14b can also irradiate light forward of the vehicle via the projection lens 20 to form a second elongated irradiation region 100b extending in the vehicle width direction W. The light source 14a is formed in such a shape that the light source shape itself corresponds to the elongated light distribution pattern in FIG. 2B, or a shape corresponding to the elongated light distribution pattern is formed by reflection adjustment by the reflector 16a, and the projection lens 20 is formed. Guided in the direction. The same applies to the light source 14b. Each reflector 16a, 16b is a reflector formed on the basis of a paraboloid of revolution, for example.

  In the present embodiment, the second irradiation region 100b is connected to the optical axis O so as to be continuous in the lateral direction of the first irradiation region 100a. FIG. 2B shows an example in which the end region of the first irradiation region 100a and the end region of the second irradiation region 100b overlap each other to form the overlap portion 100c. The overlap portion 100c can be adjusted, for example, by adjusting the arrangement of the light sources 14a and 14b and the shape of the reflectors 16a and 16b. In this way, by overlapping the first irradiation region 100a and the second irradiation region 100b at the connecting portion, when a high balm is formed, it is possible to increase the luminous intensity by superimposing light in the vicinity of the central portion. A dark part is not formed in the connection part of the 1st irradiation area | region 100a and the 2nd irradiation area | region 100b, and it can contribute to the visibility improvement at the time of high beam use, and quality improvement.

  When the first shades 12A1, 12A2 and the second shade 12B are moved to the advanced positions, at least light to the end region including the connecting portion where the first irradiation region 100a and the second irradiation region 100b are connected is shielded. It has become. In FIG. 2B, the light shielding region 102 by the first shades 12A1, 12A2 and the second shade 12B is indicated by broken lines. In the present embodiment, the sizes of the first shades 12A1 and 12A2 are determined so that the light shielding region 102 is wider than the width of the overlap portion 100c so as to completely cover the overlap portion 100c.

  In this way, by turning on the light sources 14a and 14b, by adding the first irradiation region 100a and the second irradiation region 100b to the upper part of the light distribution pattern for low beam that is separately lit, it is for the high beam in the full lamp state. A light distribution pattern can be formed. Therefore, by moving the two first shades 12A1, 12A2 and the second shade 12B forming the light-shielding region 102 to the advanced position, the light distribution pattern for the high beam can be changed without changing the lighting state of the light sources 14a, 14b. A special light distribution pattern in which a part is shielded can be formed.

  FIG. 3 shows an image example of the control state of the optical unit 10 and the light distribution pattern to be formed. 3 shows a state in which the light distribution pattern formed by the high beam optical unit 10 is added to the upper portion of the low beam light distribution pattern Lo formed by the low beam optical unit. Yes.

  The vehicle headlamp device 210 according to the present embodiment includes a light source 14a, 14b according to the position of a forward vehicle or a pedestrian in a forward area acquired by a forward viewing device mounted on the vehicle side, for example, a camera or the like. It is assumed that the optimal light distribution pattern is selected by performing the turning on / off control of the first shade 12A1 and the advance / retreat control of the first shades 12A1 and 12A2. FIG. 3 illustrates an example in which only the movement control of the first shades 12A1 and 12A2 is performed while the light sources 14a and 14b remain turned on.

  First, the control 1 for forming a complete high-beam light distribution pattern Hi1 will be described. The control unit 228 turns on the light sources 14a and 14b, and moves the first shades 12A1 and 12A2 to the retracted position by setting the moving mechanism 18 to the non-controlled state according to the presence state of the vehicle or the like in the vehicle front area. That is, by setting the complete non-light-shielding state, the first irradiation region 100a and the second irradiation region 100b including the overlap portion 100c in FIG. 2B are turned on. This state is a complete high beam irradiation state. Therefore, the visibility of the front area of the driver of the own vehicle can be improved. In addition, the formation of the overlap portion 100c increases the light intensity near the center and further improves the visibility.

  Next, control 2 is the maximum light shielding state in the lighting state of the light sources 14a and 14b. The control unit 228 and the light sources 14a and 14b are turned on, and the moving mechanism 18 is controlled according to the presence state of the vehicle or the like in the front area of the host vehicle to move the first shades 12A1 and 12A2 to the advanced positions. By shielding the light with the first shades 12A1 and 12A2, a special high beam light distribution pattern Hi2 is formed in which high beam light is not irradiated from the vicinity of the center in front of the vehicle (far distance) to the vicinity of the center of the opposite lane (short distance). it can. This applies, for example, when there are many oncoming vehicles at long distances and short distances in the oncoming lane, there are no preceding vehicles in the short distance on the own lane, and there are no pedestrians on the shoulder of the oncoming lane. Is a preferred light distribution pattern. In this case, it is possible to prevent glare from being applied to a forward vehicle existing at a long distance or an oncoming vehicle close to the opposite lane, and the driver's own sight of the driver's own lane and the visibility of the shoulder of the oncoming vehicle can be seen. Can be improved.

  Control 3 is a light distribution pattern that enables glare prevention with respect to the short distance of the oncoming lane when the light sources 14a and 14b are turned on. The control unit 228 turns on the light sources 14a and 14b and controls the moving mechanism 18 according to the presence state of the vehicle or the like in the front area of the host vehicle to move only the first shade 12A2 to the advanced position. By shielding the light with the first shade 12A2, the special high beam light distribution pattern Hi3 can be formed in which the high beam light is not irradiated to the vicinity of the center of the opposite lane. This is a light distribution pattern that is preferably applied when, for example, an oncoming vehicle exists at a short distance in the oncoming lane, a preceding vehicle does not exist at a long distance, and a pedestrian does not exist on the shoulder of the oncoming lane. In this case, it is possible to prevent glare on the oncoming vehicle on the oncoming lane side, especially at a close distance, and improve the visibility of the driver's own lane side and the far field of view and the shoulder on the oncoming lane side. Can be made.

  Control 4 is that there is a forward vehicle near the center in front of the host vehicle when the light sources 14a and 14b are lit, there is no preceding vehicle at a short distance on the own lane side, and there is no pedestrian on the opposite lane side. The light distribution pattern is preferably applied in some cases. The control unit 228 turns on the light sources 14a and 14b and controls the moving mechanism 18 according to the presence state of the vehicle or the like in the front area of the host vehicle to move only the first shade 12A1 to the advanced position. By shielding the light with the first shade 12A1, it is possible to form a special high beam light distribution pattern Hi4 that is not irradiated with high beam light near the center in front of the host vehicle. In this case, for example, there is a forward vehicle near the center (far distance) in front of the host vehicle, there is no oncoming vehicle in the near distance of the oncoming lane, and there is no preceding vehicle at a short distance on the own lane side, This light distribution pattern is preferably applied when there is no pedestrian on the opposite lane side. In this case, it is possible to prevent glare from appearing on the forward vehicle existing at a long distance in the vicinity of the center in front of the host vehicle, and the field of view of the driver's own vehicle side near distance and the opposite lane side near distance, and the shoulder on the opposite lane side. Visibility can be improved.

  In this way, by controlling the advance / retreat of the first shades 12A1 and 12A2, it is possible to form a light distribution pattern that cannot be realized only by turning on and off the light sources 14a and 14b. Further, in addition to the control of the first shades 12A1 and 12A2 of the control 1 to the control 4, more light distribution patterns can be formed by adding on / off control of the light sources 14a and 14b. For example, in the control 2 described with reference to FIG. 3, by turning on only the light source 14 a and turning off the light source 14 b, a so-called “left-side high light distribution pattern” can be formed. On the contrary, by turning on only the light source 14b and turning off the light source 14a, it is possible to form a light distribution pattern that mainly irradiates the road shoulder field of view of the opposite lane with a high beam, almost the same as the low beam light distribution pattern.

  Further, in the control 3 described with reference to FIG. 3, only the light source 14a is turned on and the light source 14b is turned off, so that the long distance near the own lane side and the center is in a high beam state, and glare to an object existing on the opposite lane side “Extended left-side high light distribution pattern” can be formed. On the contrary, by turning on only the light source 14b and turning off the light source 14a, it is possible to form an “opposite lane partial light-blocking light distribution pattern” that suppresses glare with respect to a short distance on the own lane side and the opposite lane.

  In the control 4 described with reference to FIG. 3, the “left-side high light distribution pattern” can also be formed by turning on only the light source 14a and turning off the light source 14b. On the contrary, by turning on only the light source 14b and turning off the light source 14a, a so-called “right-side high light distribution pattern” in which the opposite lane side is mainly in a high beam state can be formed.

  As described above, more light distribution patterns can be easily formed by the combination of turning on / off the first shades 12A1 and 12A2 and the light sources 14a and 14b.

  As described above, in the vehicle headlamp that forms various light distribution patterns by combining the operation of the movable shade and the light source on / off, the switching time of the light distribution pattern is instantaneous (for example, 0.1 second or less). In addition, since the brightness and darkness of the irradiation range changes abruptly, the driver of the host vehicle may be uncomfortable.

  In order to reduce this uncomfortable feeling, when the light source is composed of an LED array or the like and dimming is possible by voltage control, it is conceivable that the light source is gradually turned on or off over a relatively long time. However, generally, the moving mechanism of the movable shade uses a solenoid as a driving source, and the operation of the movable shade, that is, switching between the advanced position and the retracted position can be performed only instantaneously. Even if the luminous intensity of the light source is gradually changed, if the change of the movable shade is instantaneous, it is impossible to prevent the user from feeling an instantaneous change in brightness.

  Therefore, in the present embodiment, when a moving mechanism capable of gradually switching the movable shade is employed and the light intensity of the light source is gradually changed, the movement of the movable shade between the advanced position and the retracted position is also gradually performed. By doing so, the feeling of strangeness of light and dark changes given to the driver was reduced.

  In the present embodiment, the moving mechanism 18 employs a stepping motor or a combination of a direct current motor and a speed reducer instead of a solenoid or the like that operates instantaneously as a driving source of the movable shade. With this configuration, the movable shade can be gradually moved so as to match the light intensity change of the light source. However, even when a solenoid is used as a drive source, it is conceivable that a configuration suitable for this embodiment is obtained by incorporating an appropriate control circuit.

  FIG. 4 is a diagram for explaining how the control unit 228 controls the light source and the movable shade.

  FIG. 4A shows the state of control in the case where the lighting of the light source and the opening of the movable shade are performed simultaneously (that is, the movement from the retracted position to the advanced position). In the figure, the upper graph A1 represents the light intensity change of the light source, the middle graph A2 represents the light intensity change in the vicinity of the movable shade, and the lower graph A3 represents the position change of the movable shade.

  The controller 228 substantially matches the time from the start of lighting of the light source to the full lighting (see graph A1) and the time until the movable shade is completely moved from the advanced position to the retracted position (see graph A3). The moving mechanism 18 is controlled. That is, the movable shade is gradually moved from the advanced position to the retracted position so as to match the time until the luminous intensity of the light source is gradually increased until it is fully lit. As a result, as shown in the graph A2, the change in luminous intensity in the vicinity of the movable shade gradually increases, so that the driver feels uncomfortable due to a sudden change in illuminance in the light distribution pattern.

  Here, “substantially coincidence” means that it is not necessary to completely match the timing when the light source is fully lit and the timing when the movement of the movable shade is completed. It means that it should be. The allowable time difference is determined based on experiments or simulations. In one example, it is considered sufficient that the time difference is within about ± 10% of the time from the start of lighting of the light source to the full lighting. .

  It should be noted that, as represented by the dotted line in the graph A1, it is preferable that the luminance change rate observed by the driver becomes constant if the light intensity of the light source can be controlled to increase linearly. In this case, the control unit 228 may control the moving mechanism 18 so that the time ratio of the light intensity increase of the light source substantially coincides with the time ratio of the light shielding range decrease due to the shade.

  FIG. 4B shows a state of control in the case where the light source is turned off and the movable shade is shielded (that is, moving from the advanced position to the retracted position) at the same time. Similar to FIG. 4A, the upper graph B1 represents the light intensity change of the light source, the middle graph B2 represents the light intensity change in the vicinity of the movable shade, and the lower graph B3 represents the position change of the movable shade. .

  In this case, the control unit 228 controls the moving mechanism 18 so that the time from when the light source is fully turned on to when it is turned off substantially coincides with the time until the movable shade is completely moved from the retracted position to the advanced position. Thereby, even when the light source is turned off, the change in illuminance observed by the driver can be reduced to reduce the uncomfortable feeling.

  However, in general, when the light source is turned off, it may be preferable to turn off the light in the shortest possible time because glare is not given to the oncoming vehicle. Therefore, when the light source is turned off, the control unit may be configured so that it can be selected to turn off the light in a short time, move the movable shade, and gradually change the light source luminous intensity and shade opening.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The configuration shown in each figure is for explaining an example, and any configuration that can achieve the same function can be changed as appropriate, and the same effect can be obtained.

  DESCRIPTION OF SYMBOLS 10 Optical unit, 12A 1st shade, 12B 2nd shade, 14 Light source, 18 Movement mechanism, 20 Projection lens, 228 Control part.

Claims (3)

A shade drive unit for a vehicle lamp,
A shade capable of switching a light distribution pattern by moving between a light shielding position for shielding a part of the light emitted from a light source capable of adjusting light intensity and a retreat position for non-light shielding;
A moving mechanism that is connected to the shade and moves to any one of the light shielding position and the retracted position;
A control unit that controls the moving mechanism so that the time from the start of lighting of the light source to full lighting and the time until the shade completes moving from the light shielding position to the retracted position;
A shade drive unit comprising:   2. The shade according to claim 1, wherein the control unit controls the moving mechanism so that a time ratio of the luminous intensity increase of the light source and a time ratio of a light shielding range decrease by the shade are substantially coincided with each other. Drive unit.   The control unit controls the moving mechanism so that a time from when the light source is fully turned on to when the light source is turned off and a time until the shade is completely moved from the retracted position to the light shielding position are substantially the same. The shade drive unit according to claim 1 or 2, characterized by the above-mentioned.

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