JP2005149988A - Lighting drive device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a structure of moving a headlamp unit or a reflector in all directions up-and-down and right and left without installing a drive mechanism at the drive part, and facilitate light weight and compactness of the drive part. <P>SOLUTION: In the drive device, end part link members 1a-3a, 1c-3c are coupled rotatably to an input and an output members 4, 5 arranged respectively at the input and the output sides, and the device comprises 3 sets or more of link mechanisms 1-3 which are composed of four rotating pairs 6a-8a, 6b<SB>1</SB>, 6b<SB>2</SB>-8b<SB>1</SB>, 8b<SB>2</SB>, 6c-8c connecting rotatably the respective end part link members 1a-3a, 1c-3c of the input side and the output side to the center link members 1b-3b. The input side and the output side are geometrically identical with respect to the cross section at the center part of each link mechanisms 1-3, and the headlamp 31 is installed on the output member 5 against the fixed input member 4, and by moving the output member 5 by the movement of the link mechanisms 1-3, the optical axis of the headlamp 31 can be adjusted in all directions up-and-down and right and left. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an illumination drive device, for example, an illumination drive device used as a drive mechanism for an AFS (light distribution variable type headlight) that swings a headlight of an automobile vertically and horizontally.

  For example, in one of the lighting driving devices equipped in an automobile, an AFS (variable light distribution type headlight) in which the headlamp can be moved in all directions, up, down, left, and right according to driving conditions in order to improve the visual safety of the automobile. Drive mechanism. As an illumination drive device equipped with this AFS drive mechanism, for example, an optical axis is adjusted by electrical control by moving the light source of the headlamp unit in separate vertical and horizontal directions (for example, see Patent Document 1). ) And the one that adjusts the optical axis of the light source by moving the reflector of the headlamp unit in the vertical and horizontal directions independently (see, for example, Patent Document 2).

  The illumination driving device disclosed in the former Patent Document 1 includes a unit tilt control mechanism that tilts the headlamp unit in the vertical direction in accordance with the vehicle traveling state to vertically move the light distribution pattern, and the vehicle driving state. And a light distribution variable control mechanism that changes the light distribution pattern by moving the shade of the headlamp unit. By appropriately combining beam irradiation control by these unit tilt control mechanism and variable light distribution control mechanism, beam irradiation can be performed with a light distribution pattern and an irradiation angle that correspond to the vehicle running situation, and the visibility of the road surface ahead of the vehicle is improved. .

The illumination driving device disclosed in the latter patent document 2 includes a movable reflector that changes the light projection range of the headlamp according to the driving state of the vehicle and an infrared camera that detects an optical signal. . This movable reflector can be rotated at a predetermined swing angle by a motor via a support, a shaft, a bearing and a gear.
JP 2001-325816 A JP 2003-2137 A

  By the way, the above-described illumination driving device is a combination of a driving actuator that swings the entire headlamp unit or a part of the reflector plate left and right and an auto leveling mechanism that swings the entire headlamp unit up and down. The mechanism is a lighting drive device incorporating two actuators. Therefore, since the actuator is installed in the movable part, the drive mechanism moves integrally with the movable part, and it is difficult to reduce the weight of the movable part.

  Therefore, the present invention has been proposed in view of the above-mentioned problems, and the object of the present invention is to install a drive mechanism in the movable part, with a structure that allows the headlamp unit or reflector to move in all directions. It is an object of the present invention to provide an illumination driving device that can be realized without being performed and can easily achieve a lightweight and compact movable part.

  As a technical means for achieving the above-mentioned object, the present invention connects the end link members so as to be rotatable with respect to the input / output members respectively arranged on the input / output side. There are three or more sets of link mechanisms consisting of four rotating pairs that rotatably connect the end link members to the center link member, and the input and output sides of the cross section at the center of each link mechanism are geometrical. The light source is provided in any one of the input / output members, and the optical axis can be adjusted by moving the light source by the operation of the link mechanism. With this link mechanism, the optical axis of the light source can be moved in all directions up, down, left, and right, and it is not necessary to install a drive unit of the link mechanism in the movable part.

  In addition, as a light source described above, a vehicle headlamp can be applied. When applied to the headlight of this automobile, it is desirable to adjust the optical axis by operating the above-mentioned link mechanism based on the output signals of various sensors detected from the driving state of the automobile.

  In the above-described configuration, a structure in which a light source is provided with a reflecting plate that restricts a light projection range by the light source is possible. In this case, either the whole or a part of the reflecting plate is moved to move the optical axis of the light source. Can be adjusted.

  Each of the three or more sets of link mechanisms provided between the input and the output has the same geometric shape, and the reason why the three or more sets of link mechanisms are set is to provide a two-degree-of-freedom mechanism. Here, “the input side and the output side are geometrically identical with respect to the cross section at the center of the link mechanism” means that the input side and the output side are separated on the symmetry plane of the central link member. It means that the geometric shape on the output side is the same.

  Each link mechanism constitutes a three-bar chain composed of four rotating pairs. The end link members on the input side and the output side have a spherical link structure, and the spherical link centers in the three or more sets of link mechanisms coincide with each other, and the distances from the centers are also the same. The rotation pair axis that becomes the connecting portion between the end link member and the central link member may have a certain crossing angle or may be parallel. However, the shape of the central link member in the three or more sets of link mechanisms is geometrically the same.

Further, in the above-described configuration, the present invention is provided with a rotation angle detecting means for measuring the rotation angle of the end link member at the rotation pair between the input member and the end link member in the two or more link mechanisms. A structure is desirable. Further, if the link actuating actuator is connected to the input side end link member via the rotation transmission unit, the attitude of the output member defined by the bending angle θ and the turning angle φ and the input side end link Relational expression with the rotation angle βn of the member (γ is the axial angle of the central link member, δ is the circumferential separation angle of each end link member with respect to the reference end link member),
cosθsinβn−sinθsin (φ + δn) cosβn + sinγ = 0
The optical axis can be adjusted by controlling the attitude of the output member by using the inverse transformation by the above, or by detecting the attitude of the output member by using the forward transformation by the above-described relational expression.

  Here, in the attitude of the output member, the “fold angle θ” is a vertical angle at which the output member is inclined with respect to the central axis of the input member, and the “swivel angle φ” is the central axis of the input member. It means a horizontal angle at which the output member is inclined. “Rotation angle βn” means the rotation angle at the connecting end of the end link member rotatably connected to the input member. Further, the “axis angle γ” means a connecting end shaft of a central link member rotatably connected to an input side end link member and a central link member rotatably connected to an output side end link member. Means the angle formed by the connecting end axis. The “separation angle δ” defines the circumferential position distance of each end link member relative to the reference end link member on the input side, and is defined by each of the connecting end shafts of the end link member and the input member. Means angle. In addition, “inverse transformation based on the relational expression” means obtaining the rotation angle of the end link member on the input side with respect to the posture input by inputting a target value that defines the posture of the output member into the relational expression. , "Forward conversion by relational expression" means to obtain the attitude of the output member relative to the rotation angle input by inputting a target value defining the rotation angle of the input side end link member into the relational expression. .

  According to the present invention, the end link members are rotatably connected to the input / output members respectively arranged on the input / output side, and the end link members on the input side and the output side are connected to the central link member. There are three or more sets of link mechanisms consisting of four rotating pairs connected in a rotatable manner, the input side and the output side are geometrically identical with respect to the cross section at the center of each link mechanism, and any of the input / output members By providing a light source on either side and moving the light source by the operation of the link mechanism so that the optical axis can be adjusted, a structure for moving the optical axis of the light source in all directions up, down, left, and right is provided in a movable mechanism. The movable part can be easily made lightweight and compact, and its practical value is great.

  An embodiment in which the present invention is applied to an illumination driving device for an automotive headlamp will be described in detail below. FIG. 1 illustrates an illumination driving device that controls the attitude of a headlamp unit 30. The headlamp unit 30 includes a headlamp 31 that is a light source and a parabolic antenna-shaped reflector 32, which will be described in detail below. It is installed in the drive unit A composed of the link mechanisms 1 to 3 described below. FIG. 2 shows a drive unit A of the illumination drive device of FIG. 1 and includes three sets of link mechanisms 1 to 3 that are geometrically identical in shape. The link mechanisms 1 to 3 are preferably made of a resin member when manufacturing an inexpensive and light illumination driving device.

As shown in FIG. 2, each of the link mechanisms 1 to 3 of the drive unit A includes input side end link members 1 a to 3 a that are rotatably connected to a disk-shaped input member 4, and a disk-shaped output member. Output side end link members 1c to 3c, which are rotatably connected to 5, and both end link members 1a to 3a, 1c to 3c, which are rotatably connected to both end link members 1a to 3a, It is composed of a central link member 1b~3b connecting together 1C～3c, eggplant four rotating pair section _{6a~8a, 6b 1, 6b 2 ~8b} 1, 8b 2, a three-section chain structure consisting 6C～8c.

  In the illumination driving apparatus of this embodiment, the input member 4 is fixed as shown in FIG. 1, and the headlamp 31 and the reflector 32 are fixed to the output member 5. In addition, link operation actuators 41 and 42 are installed on the two end link members 2a and 3a on the input side, respectively. As the link actuating actuators 41 and 42, a DC motor, a pulse motor, or the like can be used, and a speed reducer can be interposed in the preceding stage. By operating the link mechanisms 1 to 3 with the actuators 41 and 42, the headlamp 31 and the reflecting plate 32 can be moved to direct their optical axes in all directions.

  As another embodiment, for example, as shown in FIG. 4, the input member 4 is fixed, the reflector 32 is fixed to the input member 4 via the housing 33, and the headlamp 31 is attached to the output member 5. Thereby, only the headlamp 31 can be moved and the optical axis can be directed to all directions up and down, right and left. The housing 33 described above has a size that does not interfere with the link mechanisms 1 to 3. Moreover, although the reflecting plate 32 is being fixed to the input member 4 via the housing 33, other fixed parts may be sufficient.

  Furthermore, as another embodiment, for example, as shown in FIG. 5, the headlamp 31 and the split type lower reflector 32 b are fixed to the mounting base 52, and the input member 4 is fixed to the mounting base 52. On the other hand, the split type upper reflector 32 a is attached to the output member 5 via the support member 51. Thereby, the upper reflecting plate 32a can be moved with respect to the fixed headlamp 31 and the lower reflecting plate 32b, and the optical axis thereof can be oriented in all directions.

The end link members 1a to 3a and 1c to 3c have a spherical link structure, and the spherical link centers in the three sets of link mechanisms 1 to 3 coincide with each other, and the distances from the centers are also the same. The connecting shafts of the rotating pairs 6b ₁ , 6b _{2 to} 8b ₁ , 8b ₂ of the end link members 1a to 3a and 1c to 3c and the central link members 1b to 3b may have a certain crossing angle or are parallel to each other. May be. However, the shapes of the central link members 1b to 3b in the three sets of link mechanisms 1 to 3 are geometrically the same.

  FIG. 3 shows the rotation pair 6a to 8a of the input member 4 and the input side end link members 1a to 3a in the above-described embodiment. On the upper surface of the input member 4 having a disk shape, a pair of support members 11a to 13a are installed for the link mechanisms 1 to 3. Bearings 17a to 19a are attached to the pair of support members 11a to 13a, and L-shaped end links are formed on the support rods 14a to 16a rotatably supported between the two bearings 17a to 19a. One arm end of each of the members 1a to 3a is inserted and disposed between the pair of support members 11a to 13a. The support members 11 a to 13 a have a structure that can be attached to and detached from the input member 4 with screws or the like, but can also be formed integrally with the input member 4.

  Note that the arm ends of the end link members 1a to 3a are fixed to the support bars 14a to 16a by set screws. The ends of the support bars 14a to 16a can be adjusted by applying a predetermined preload to the bearings 17a to 19a by interposing a spacer or the like by tightening with nuts 20a to 22a.

  The circumferential positions of the support members 11a to 13a may not be equally spaced, but the input member 4 and the output member 5 need to have the same circumferential positional relationship. The input member 4 and the output member 5 are shared by the three sets of link mechanisms 1 to 3, and the end link members 1a to 3a and 1c to 3c are connected to the support members 11a to 13a and 11c to 13c. Although the input member 4 and the output member 5 to which the support members 11a to 13a and 11c to 13c are attached are disk-shaped members in the drawing, it is possible to secure a mounting space for the support members 11a to 13a and 11c to 13c. Any shape is possible as long as it is possible. Further, if it is necessary to pass wiring or the like, a through hole can be formed.

  The rotation pair 6c-8c, which is a connecting portion between the output member 5 and the output side end link members 1c-3c, is a rotation pair 6a between the input member 4 and the input side end link members 1a-3a. Since it has the same structure as ˜8a, the duplicate description is omitted.

In the rotation pair portions 6b _{1 to} 8b ₁ between the input side end link members 1a to 3a and one end of the central link members 1b to 3b, the other arm end of the input side end link members 1a to 3a Is connected to one end of the central link members 1b to 3b which are substantially L-shaped. A pair of support members 11b _{1 to} 13b ₁ are provided at _one end of the central link members 1b to 3b. Bearings (not shown) are attached to the pair of support members 11b _{1 to} 13b ₁ , and the support rods 14b _{1 to} 16b ₁ rotatably supported between the two bearings have an L shape. the other arm end of the end links 1a~3a are connected are inserted and disposed between the pair of support members 11b ₁ 13 b _1. The support members 11b _{1 to} 13b ₁ may have either a structure that can be attached to and detached from the central link members 1b to 3b with screws or an integral structure.

Incidentally, the arm end portion of the end links 1a~3a is fixed to the support rod 14b ₁ ~16b ₁ by a set screw. The ends of the support rods 14b _{1 to} 16b ₁ can be adjusted by applying a predetermined preload to the bearing by interposing a spacer or the like by tightening with a nut.

The rotary pair portions 6b _{2 to} 8b ₂ , which are connecting portions between the other arm end portions of the output side end link members 1c to 3c and the other end portions of the central link members 1b to 3b, since parts link the same structure as rotating pair section 6b ₁ ~8b ₁ and one end of the other arm end of the member 1a~3a and central link member 1b to 3b, duplicate description is omitted.

  In the link mechanisms 1 to 3, the angles and lengths of the support rods 14a to 16a and 14c to 16c of the input / output members 4 and 5 and the geometric shapes of the end link members 1a to 3a and 1c to 3c are When the shape is the same on the output side, and the shape of the central link members 1b-3b is the same on the input side and the output side, the central link members 1b-3b and the input / output members 4, with respect to the symmetry plane of the central link members 1b-3b. 5 and the end link members 1a to 3a and 1c to 3c connected to the input side 4 and the input side end link member from the geometrical symmetry. 1a to 3a, the output member 5 and the output side end link members 1c to 3c move in the same manner, and the input side and the output side rotate at the same speed at the same rotation angle. The plane of symmetry of the central link members 1b to 3b when rotating at a constant speed is referred to as a uniform speed bisector.

  For this reason, by arranging a plurality of link mechanisms 1 to 3 having the same geometric shape sharing the input / output members 4 and 5 on the circumference, the central link member 1b is a position where the plurality of link mechanisms 1 to 3 can move without contradiction. -3b is limited to the movement only on the uniform speed bisector, so that constant speed rotation can be obtained even if the input side and the output side take any operating angle.

Four rotating pair section 6a~8a in each link mechanism _{1~3, 6b 1, 6b 2 ~8b} 1, 8b 2, 6c~8c, i.e., a connecting portion of the input member 4 and the end links 1a to 3a, Input side end link members 1a to 3a and central link members 1b to 3b are connected, central link members 1b to 3b are connected to output side end link members 1c to 3c, and output side end link members are connected. By making the connecting part between 1c to 3c and the output member 5 into a bearing structure, it is possible to reduce the rotational resistance by suppressing the frictional resistance at the connecting part, and to ensure smooth power transmission and durability. It can be improved. Furthermore, each rotary pair section 6a~8a linkage _{1~3, 6b 1, 6b 2 ~8b} 1, 8b 2, wherein each rotary pair section 6a~8a to both ends support 6c~8c, 6b _1, 6b _{Since the} bearings are arranged at _{2 to} 8b ₁ , 8b ₂ and 6c to 8c, the bearing rigidity can be improved. Further, since parts can be attached and detached at portions other than the rotating pair portion, the assemblability can be improved. In this embodiment, each rotary pair section 6a~8a linkage _{1~3, 6b 1, 6b 2 ~8b} 1, 8b 2, but has a structure that both ends supporting 6C～8c, to cantilever structure It may be.

  The illumination drive device of this embodiment has a structure in which the output shafts of the actuators 41 and 42 are coaxially connected to support rods 14a to 16a connected to arm ends of input side end link members 1a to 3a. To do. By controlling the rotational angle positions of the end link members 1a to 3a by the actuators 41 and 42, the posture of the output member 5 is controlled to move the headlamp 31, the reflector 32, and the upper reflector 32a. The optical axis can be oriented in all directions.

  The actuator for controlling the rotation angle position of the input side end link members 1a to 3a is not limited to the structure of the above-described embodiment, and the rotation pair between the input side end link members 1a to 3a and the input member 4 is not limited. A structure in which a rotation transmission part (not shown) is provided in the parts 6a to 8a and an actuator is connected via the rotation transmission part is also possible. For example, a gear is attached to the ends of the support rods 14a to 16a supported on the support members 11a to 13a via bearings 17a to 19a, and connected to an actuator such as a motor via this gear. The actuator may be arranged below the input member 4 and accommodated in a housing (not shown) and connected to a gear through a through hole formed in the input member 4.

  As another embodiment, a rotation angle sensor (not shown) may be provided on the support rods 14a to 16a that support the input side end link members 1a to 3a. In this way, it is not necessary to attach a servo mechanism to the actuator, so that the actuator can be made compact and the origin is not required when the power is turned on. The rotation angle sensor described above detects a change in magnetic flux generated by the rotation of the end link member, and generates a single-side magnetic field operation type or alternating magnetic field operation type rectangular output that generates an output signal corresponding to the magnetic flux density. Magnetic sensors can be used. When the support rods 14a to 16a are rotated by the rotation of the end link member, an output signal corresponding to the magnetic flux density is generated by the rotation angle sensor, and the rotation angle of the support rods 14a to 16a, that is, the end link members 1a to 3a. The rotation angle can be detected. Although the magnetic sensor alone functions as an encoder for A-phase or Z-phase output, a bearing with a rotation angle sensor for AB-phase output or ABZ-phase output can be used in addition to the magnetic sensor.

In this embodiment, as shown in FIG. 1, a relational expression between the attitude of the output member 5 defined by the bending angle θ and the turning angle φ and the rotation angle βn of the end link members 1a to 3a on the input side (γ is the center) The axial angles of the link members 1b to 3b, δ is the circumferential separation angle of each end link member with respect to the reference end link member),
cosθsinβn−sinθsin (φ + δn) cosβn + sinγ = 0
The posture of the output member 5 can be controlled by using the inverse transformation by.

  That is, the posture of the output member 5 can be defined by two degrees of freedom (fold angle θ and turning angle φ) as shown in FIG. 2, and the posture of the output member 5 (fold angle θ and turning angle φ) and the input The relationship with the rotation angle βn of the end link member on the side can be defined by the following equation.

The parameter θ in the following relational expression is the angle at which the output member 5 is inclined in the vertical direction with respect to the input member 4, and the parameter φ is the angle at which the output member 5 is inclined from 0 ° to the horizontal direction with respect to the input member 4. The angles and parameters β ₁ and β ₂ (there are three sets of link mechanisms, which can be defined by two of them) are the rotations at the rotation pair portions 6a to 8a of the input side end link members 1a to 3a. The angle and the parameter γ are connected to the rotation pair parts 6b _{1 to} 8b _{1 of} the central link members 1b to 3b connected to the input side end link members 1a to 3a and the output side end link members 1c to 3c. It is an angle formed by the rotating pair portions 6b _{2 to} 8b _{2 of} the central link members 1b to 3b. This relational expression is a case where the link mechanisms 1 to 3 are in three sets and the circumferential positions of the end link members 1a to 3a and 1c to 3c are equally spaced.
cosθsinβ ₁ −sinθsinφcosβ ₁ + sinγ = 0
_{cosθsinβ 2 -sinθsin (φ + 120 °} ) cosβ 2 + sinγ = 0
_{cosθsinβ 3 -sinθsin (φ + 240 °} ) cosβ 3 + sinγ = 0

  By solving these two or more equations, the posture of the output member 5 can be controlled by inverse transformation of the relational expression. That is, the attitude control of the output member 5 can be realized by obtaining a rotation angle of the input side end link members 1a to 3a with respect to the attitude input by inputting a target value defining a predetermined attitude into the relational expression. .

  In the above-described embodiment, the case where the rotation angle sensor (not shown) is provided on the support rods 14a to 16a for supporting the input side end link members 1a to 3a has been described. It is also possible to install a device, or to install an attitude detection device such as a gyro on the output member 5. In that case, the posture of the output member 5 can be detected by forward conversion of the relational expression. That is, the posture detection of the output member 5 can be realized by measuring the rotation angle of the input side end link members 1a to 3a and inputting the measured value to the relational expression. By detecting the posture of the output member 5, The headlamp 31, the reflector 32, and the upper reflector 32a can be moved to direct their optical axes in all directions.

  In addition to the illumination driving device that moves the headlight in all directions up, down, left, and right according to the driving situation in order to improve the visual safety of the automobile, the present invention provides various other things such as backlight illumination and laser irradiation. It is applicable to various uses.

It is a perspective view which shows the illumination drive device applied about the headlamp of the motor vehicle in embodiment of this invention. It is a perspective view which shows the link mechanism integrated in the illumination drive device of FIG. FIG. 3 is a cross-sectional view showing a rotating pair of an input member and an input side end link member in the illumination driving device of FIGS. 1 and 2. It is a perspective view which shows the illumination drive device made to move only a headlamp in other embodiment of this invention. In another embodiment of the present invention, it is a perspective view showing an illumination driving device in which a part of a split type reflector is movable.

Explanation of symbols

1-3 linkage 1a~3a, 1c~3c end link member 1b~3b intermediate link member 4 input member 5 output member 6a~8a rotation pair portion _{6b 1, 6b 2 ~8b 1,} 8b 2 rotating pair section 6c~ 8c Rotating pair 31 Light source (headlight)
32 reflector θ bending angle φ turning angle βn rotation angle

Claims (9)

  Four end link members are rotatably connected to the input / output members respectively arranged on the input / output side, and each end link member on the input side and the output side is rotatably connected to the central link member. There are three or more link mechanisms consisting of two rotating pairs, the input side and the output side are geometrically the same with respect to the cross section at the center of each link mechanism, and a light source is provided on one of the input / output members An illumination driving apparatus characterized in that the optical axis can be adjusted by moving the light source by the operation of the link mechanism.   The illumination drive device according to claim 1, wherein a reflection plate that restricts a light projection range of the light source is attached to the light source.   The illumination driving device according to claim 2, wherein either the whole or a part of the reflecting plate is movable to adjust the optical axis of the light source.   The rotation angle detection means which measures the rotation angle of the said end part link member was attached to the rotation pair part between the said input member and end part link member in two or more link mechanisms. The illumination drive device described in 1.   The illumination driving device according to claim 4, wherein a link actuating actuator is connected to the input side end link member via a rotation transmission unit. Relational expression between the attitude of the output member defined by the bending angle θ and the turning angle φ and the rotation angle βn of the end link member on the input side (γ is the axial angle of the central link member, δ is the reference end link member Circumferential separation angle of each end link member with respect to
cosθsinβn−sinθsin (φ + δn) cosβn + sinγ = 0
The illumination driving device according to claim 4, wherein the optical axis can be adjusted by controlling the attitude of the output member by inverse conversion by the method. Relational expression between the attitude of the output member defined by the bending angle θ and the turning angle φ and the rotation angle βn of the end link member on the input side (γ is the axial angle of the central link member, δ is the reference end link member Circumferential separation angle of each end link member with respect to
cosθsinβn−sinθsin (φ + δn) cosβn + sinγ = 0
The illumination driving device according to claim 4 or 5, wherein the optical axis can be adjusted by detecting the attitude of the output member by forward conversion according to claim 6.   The illumination driving device according to any one of claims 1 to 7, wherein the light source is a headlight of an automobile.   The illumination driving device according to claim 8, wherein the optical axis is adjusted by operating a link mechanism based on output signals of various sensors detected from the driving state of the automobile.