Vehicle lamp

A vehicle lamp 10 is provided with a lamp unit 30 which applies beams of the desired patterns ahead, and a double axis actuator 50 having a first drive mode in which the lamp unit is rotated in one of two planes that are orthogonal to each other and a second drive mode in which the lamp unit is rotated in the other of the two planes. The double axis actuator is provided with a single output part 540 which rotates the lamp unit in the two planes, and a drive part (including a drive source 550 and a movable part 561) which drives the output part. The double axis actuator can rotate the lamp unit in the each plane regardless of the rotational positions along the above two planes.

This application claims foreign priority from Japanese Patent Application Nos. 2005-293563 filed on Oct. 6, 2005 and 2006-214553 filed on Aug. 7, 2006, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicle lamp in which an irradiation direction is adjustable in a horizontal direction and a vertical direction that are orthogonal to each other.

2. Related Art

There is a vehicle lamp which can adjust an irradiation direction in a horizontal direction and in a vertical direction according to a running condition of the vehicle.

For example, in an automotive headlamp, there is a case where the irradiation direction is too upward or too downward depending on a load. In such the case, it is necessary to change the irradiation direction in the downward direction or in the upward direction timely to correctly make the irradiation direction. Further, in case that the vehicle runs on a zigzag road or turns an intersecting point, it is convenient that the irradiation direction can be changed to the left or right in order to illuminate quickly a road surface in the running direction of the vehicle.

For example, in a vehicle lamp described in JP-A-2005-119463, to achieve the above object, there are provided an actuator for rotating a lamp unit in the horizontal direction and another actuator for tilting the lamp unit in the vertical direction.

Further, in a vehicle lamp described in JP-A-2005-186731, to achieve the above object, there is provided a double axis actuator in which an actuator for rotating a lamp unit in the horizontal direction and another actuator for tilting the lamp unit in the vertical direction are built in a single housing, and output parts of these actuators are respectively coupled to separate portions of the lamp unit.

Further, in a vehicle lamp described in JP-A-2003-054310, to achieve the above object, a single drive part and a single output part are provided, and the output part acts on worked parts of the lamp unit that are different from each other.

In the vehicle lamp described in JP-A-2005-119463, there are separately provided the actuator for rotating the lamp unit in the horizontal direction and another actuator for tilting the lamp unit in the vertical direction. Therefore, the number of attachment steps of the actuator and the number of harnesses for power supply and control increase, which causes increases of space and cost. This is contrary to size-reduction and cost-reduction. Further, in the vehicle lamps provided right and left, the actuators cannot be used in common. This point also causes the increase of cost.

In the vehicle lamp described in JP-A-2005-186731, the two actuators for the two operations are built in the single housing, whereby this vehicle lamp can perform the size reduction and the cost reduction, compared with the vehicle in JP-A-2005-119463. However, since the output part of the actuator for the horizontal rotation and the output part of the actuator for the up-down tilt are respectively located in the separate positions, this double axis actuator can be used in only the lamp unit in which the positional relation between the portions connected to the two output parts is the same. In result, general-purpose properties are poor, and every time the lamp unit is different, a dedicated double axis actuator is required. Further, since the left and right vehicle lamps forms a pair, the dedicated double axis actuator is required for each of the left and right lamp assemblies.

In the vehicle lamp described in JP-A-2003-054310, the above problems in the above two vehicle lamps are eliminated.

However, before one operation, for example, the horizontally rotational operation reaches a limit position, for example, before the lamp unit faces right in front, the tilting operation in the vertical direction cannot be performed. Namely, the operations in the two different directions cannot be independently performed, and the other operation cannot be performed even in case that their operations are put in the any states.

In view of the above problems, an object of the invention is to enable use of a drive unit in many kinds of vehicle lamps thereby to heighten general-purpose properties of the drive unit, enable the independently rotational operations of the lamp unit along two planes orthogonal to each other, and enable the other operation even in case that their operations are put in any states.

SUMMARY OF THE INVENTION

In accordance with one or more embodiments of the present invention, a vehicle lamp is provided with: a lamp unit which applies beams of the desired patterns ahead; and a drive unit that actuates the lamp unit to move in a first drive mode and a second drive mode. The lamp unit is rotated in one of two planes that are orthogonal to each other (a first plane) in the first drive mode, and the lamp unit is rotated in the other of the two planes (a second plane orthogonal to the first plane) in the second drive mode. The drive unit includes a single output part that moves the lamp unit in the two planes, and a drive part that drives the output part. The drive unit actuates the lamp unit independently in each plane regardless of a position of the lamp unit in the two planes.

Therefore, in the vehicle lamp, the lamp unit is coupled to the output of the drive unit at one point, and the drive unit can independently rotate the lamp unit in each plane regardless of the rotational positions of the lamp unit in the above two planes.

Further, in the vehicle lamp, the lamp unit is coupled to the output of the drive unit at one point, so that one drive unit can be used in almost of all kinds of lamp units, and at least many kinds of lamp units. Further, since the drive unit can independently rotate the lamp unit in each plane regardless of the rotational positions of the lamp unit in the two planes, there is no limit in rotation control of the lamp unit, so that beams can be applied in the desired direction.

Further, in the vehicle lamp, the vehicle lamp may include a support shaft which is rotatable and tiltable with respect to a housing. The lamp unit is supported by the support shaft. The output part is coupled with the lamp unit at a portion on the opposite side to a portion where the lamp unit is coupled with the support shaft. The lamp unit is rotated around the support shaft, when the output part rotates, in the first drive mode. The lamp unit is tilted together with the support shaft, when the output part moves linearly in a direction substantially orthogonal to an axial direction of the support shaft, in the second drive mode. Therefore, the support structure of the lamp unit in relation to the housing is simplified, which contributes to cost reduction.

Further, in the vehicle lamp, the output part may be located on a vertical plane including an optical axis of the lamp unit. Therefore, the lamp units having the same structure can be used left and right, which contributes to the cost reduction.

Further, in the vehicle lamp, the drive part may include two drive sources, and two movable parts independently moved by the drive sources. The two drive sources and the two movable parts are arranged in right and left symmetry with a vertical plane including a linear movement direction of the output part.

When the two movable parts are moved in reversed phase, the output part rotates. When the two movable parts are moved in the same phase, the output part linearly moves. Therefore, the driving unit having the same structure can be used in the left and right lamp units, which contributes to the cost reduction.

Further, the vehicle lamp may comprises: an abnormality sensor that detects abnormality of the drive unit; an irradiation position sensor that detects an irradiation position in a vertical direction of the lamp unit; and an abnormal time position controller that positions the lamp unit below a predetermined irradiation position in case that the abnormality sensor detects the abnormality of the drive unit. Therefore, in case that trouble occurs in one of the drive parts, it is possible to prevent the irradiation position from being left above the predetermined position.

In addition, in accordance with one or more embodiments of the present invention, a drive unit for actuating a lamp unit of a vehicle lamp is provided with: a single output part for coupling to the lamp unit; and a drive for driving the single output part, and the single output part is adapted to move such that the lamp unit is rotatable independently in two orthogonal planes.

Further, in the drive unit, the single output part may be adapted to rotate about its axis and move linearly in a direction substantially perpendicular to said axis.

Further, the drive unit may include a slide base which is linearly movable, the single output part being supported by the slide base and rotatable with respect to the slide base.

Further, in the drive unit, the drive may include two drive sources and two movable transmission elements independently associated respectively therewith, the single output part being driven by movement of the transmission elements.

Further, in the drive unit, the transmission elements may be arranged such that when the transmission elements are moved in opposing phase the single output part rotates, and when the transmission elements are moved in the same phase the single output part moves linearly.

Further, in the drive unit, the single output part may be connected to the two transmission elements via respective arms.

Further, in the drive unit, the arms may respectively include coupling holes that are elongated radially about the axis of the single output part.

Further, in the drive unit, the two drive sources may be respectively supported rotatably in the right and left direction.

Further, the drive unit may include: a control circuit for controlling the drive, based on a signal from a sensor, such that the lamp unit is selectively rotatable in one of the two orthogonal planes.

Further, the drive unit may include a connector that receives a control signal from a sensor, and the single output part, the drive, the control circuit and the connector may be accommodated in a housing.

In addition, in accordance with one or more embodiments of the present invention, a drive assembly for actuating the lamp unit is provided with the drive unit and a support for supporting the lamp unit movably about a reference position.

Further, in the drive assembly, the support may include a gimbal.

In addition, in accordance with one or more embodiments of the present invention, a lamp assembly is provided with: the drive assembly; and a lamp unit, and the lamp unit is supported by the support and the single output part of the drive unit is coupled with the lamp unit on an opposite side of the lamp. unit to the support.

Further, in the lamp assembly, the support may include a support shaft, the lamp unit being adapted to be rotated in the first plane around the support shaft, and rotated in the second plane together with the support shaft.

In addition, in accordance with one or more embodiments of the present invention, a lamp assembly is provided with: the drive unit; and a lamp unit coupled with the single output part of the drive unit.

Further, in the lamp assembly, the axis of the single output part may intersect an optical axis of the lamp unit.

In addition, in accordance with one or more embodiments of the present invention, a vehicle lamp assembly is provided with: the drive unit; an abnormality sensor that detects an abnormality of the drive unit; an irradiation position sensor that detects an irradiation position in a vertical direction of the lamp unit; and an abnormal time position controller that positions the lamp unit below a predetermined irradiation position in the vertical direction in case that the abnormality sensor detects abnormality of the drive unit.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Exemplary embodiments of the invention will be described with reference to the accompanying drawings. In the exemplary embodiments, a vehicle lamp is applied to an automotive headlamp.

Firstly, referring toFIGS. 1 to 8, a first exemplary embodiment will be described.

With reference toFIG. 1, an outline of an automotive headlamp will be described.

An automotive headlamp10includes a housing20having a lighting room21which is space that is closed nearly airtightly, and a lamp unit30which is arranged in the housing20rotatably in the vertical direction and in the right and left direction.

The housing20is unmoveably fixed to a vehicle body. In the housing20, a front opening of a lamp body22having the shape of a container which opens forward is covered with a transparent cover23.

In the shown automotive headlamp10, the lamp unit30is supported through a bracket40by the lamp body22tiltably in the vertical direction and in the right and left direction (horizontal direction). However, the lamp unit30may be directly supported by the lamp body22rotatably in the vertical direction and in the right and left direction.

A double axis actuator50which is a drive unit is supported by the bracket40, and the lamp unit30supported by the bracket40rotatably in the vertical direction and in the right and left direction is coupled to an output part of the double axis actuator50.

Further, in the housing20, a discharge bulb switching circuit60is arranged, and the lamp unit30is switched on by the discharge lamp switching circuit60.

As known fromFIGS. 1 and 2, the lamp unit30includes a reflector31, a discharge bulb32supported by the reflector31, a coupling part33attached onto a front end of the reflector31, a projection lens34arranged so as to cover an opening located at a front end of the coupling part33, and a shade35provided for the coupling part33. The light which is emitted from the discharge bulb32and reflected by the reflector31is condensed in the vicinity of an upper edge35aof the shade35. The condensed light is projected forward by the projection lens34having a focus in the vicinity of the upper edge35aof the shade35, whereby a beam having the predetermined luminous distribution pattern is formed. The luminous distribution pattern has, on its upper edge, a cut-off line limited by the upper edge35aof the shade35.

From the upper surface of the coupling part33, a shaft36is protruded upward, and a self-aligning metal37is fitted at the outside of the shaft36. The self-aligning metal37has a peripheral surface37ahaving a nearly spherical shape, and a center hole37b, and the shaft36is inserted into the center hole37bslidably.

In a position of the lower surface of the coupling part33corresponding to the shaft36, a coupling boss33is projected. The coupling boss38has a nearly circular outer shape, and includes a fitting recess part38awhich opens to the lower surface. On the inner surface of the fitting recess part38a, not-shown plural engagement notches are provided.

A line connecting an axis of the shaft36and an axis of the coupling boss38is located on a vertical plane where an optical axis x-x of this lamp unit30is located.

The bracket40, as known fromFIGS. 1 and 2, includes a main part41formed in the shape of a saucer which opens forward and has a big opening41a, an upper support piece42which projects from the upper end of the main part41forward, a lower support piece43which projects from the lower end of the main part41forward, and coupling pieces44,45,46which project from three corner portions of the main part41.

In the center in the left and right direction of the front end portion of the upper support piece42, a support recess part42awhich dents forward is formed. The forward facing surface of the support recess part42ais formed in the shape of a concave spherical surface. On both sides of the front end surface of the upper support piece42with the support recess part42abetween, threaded holes42b,42bare formed. Onto the front end portion of the upper support piece42, a metal holder47is attached. In the center portion in the left and right direction of the metal holder47, a press part47athat dents backward is formed. The backward facing surface of the press part47ais formed in the shape of a concave spherical surface. On both sides of the metal holder47with the press part47abetween, screw insertion holes47b,47bare formed. Further, at the upper edge portion of the metal holder47, a regulating part47dwhich protrudes backward is formed. In a state where the metal holder47is brought into contact with the front end of the upper support piece42, and the regulating part47dcovers the upsides of the press part47aand the support recess part42a, screws47c,47cinserted from the front side into the screw insertion holes47b,47bare tightened into the threaded holes42b,42bof the upper support piece42, whereby the metal holder47is attached onto the front end portion of the upper support piece42. Hereby, between the support recess part42aof the upper support piece42and the press part47aof the metal holder47, a spherical reception concavity is formed.

In a position near the front end of the lower support piece43, an elongated hole43awhich is elongated in the front and back direction is formed. The nearly central portion in the front and back direction of this elongated hole43ais located in a position to which the position where the reception concavity is formed corresponds in up-down relation. Into the elongated hole43a, a thrust metal43bwhich is a size smaller than the elongated hole43aand formed in the shape of a track that is long back and forth is fitted and fixed. The width of the track shaped-opening part of this thrust metal43bis larger slightly than the outer size of the coupling boss38of the lamp unit30. Further, from the left and right of the back end portion of the lower support piece43, attachment pieces43c,43c(only one is shown inFIG. 2) project, and in the attachment pieces43c,43c, not-shown threaded holes are formed.

The coupling boss38of the lamp unit30is engaged with the thrust metal43battached onto the lower support piece43of the bracket40slidably in the front and back direction, and the self-aligning metal37fitted at the outside of the shaft36protruding from the upper surface of the lamp unit30is rotatably supported by the support recess part42aof the upper support piece42of the bracket40and the press part47aof the metal holder47. Hereby, the lamp unit30is supported through the bracket40by the lamp body22rotatably in two planes (a first plane and a second plane) that are orthogonal to each other. Namely, the lamp unit30can rotate in the plane orthogonal to an axis connecting the shaft36and the coupling boss38around the axis. Further, by the front and back movement of the coupling boss38in the thrust metal43b, the lamp unit30can rotate in the plane including the axis connecting the shaft36and the coupling boss38and an axis passing through the center in the width direction of the thrust metal43band extending back and forth.

The bracket40is supported by the lamp body22tiltably in the vertical direction and in the left and right direction. Namely, the bracket40is coupled to a back surface wall22aof the lamp body22at the coupling piece44by a rotational fulcrum part48, and at the two coupling pieces45,46by a space adjuster49,49.

The rotational fulcrum part48includes a fulcrum shaft48asupported by the coupling piece44, and a ball receiver48bsupported by the back surface wall22aof the lamp body22. The fulcrum shaft48aincludes a shaft part48cof which the front end portion is fixed onto the coupling piece44, and a spherical body48dformed at the back end of the shaft part48c. The spherical body48dis fitted into a spherical recess part48eformed in the ball receiver48b, and the spherical body48drotates in the spherical recess part48e, whereby the shaft part48ccan tilt.

The space adjuster49includes a nut body49asupported by the coupling piece45(46), and an adjusting shaft49brotatably supported by the back surface wall22aof the lamp body22. A screw shaft part49cof the adjusting shaft49bis tightened into the nut body49a.

For example, when the adjusting shaft49bis rotated in the nut body49asupported by the coupling piece45, the screw shaft part49cis screwed into the nut body49aor loosen from the nut body49aaccording to the rotational direction of the adjusting shaft49b. Hereby, the space between the coupling piece45and the back surface wall22aof the lamp body22becomes wide or narrow. Namely, the coupling piece45moves forward or backward. Hereby, the bracket40tilts nearly in the left and right direction with a line connecting the coupling portion between the spherical body48dof the rotational fulcrum part and the spherical recess part48eto the coupling piece46as a rotational axis. Further, when the adjusting shaft49bis rotated in the nut body49asupported by the coupling piece46, the screw shaft part49cis screwed into the nut body49aor loosen according to the rotational direction of the adjusting shaft49b. Hereby, the space between the coupling piece46and the back surface wall22aof the lamp body22becomes wide or narrow. Namely, the coupling piece46moves forward or backward. Hereby, the bracket40tilts nearly in the vertical direction with a line connecting the coupling portion between the spherical body48dof the rotational fulcrum part and the spherical recess part48eto the coupling piece45as a rotational axis.

The above double axis actuator50is supported by the bracket40on the downside of the lower support piece43of the bracket40.

The double axis actuator50is a drive unit having a first drive mode in which the lamp unit30is rotated in one of two planes that are orthogonal to each other and a second drive mode in which the lamp unit30is rotated in the other of the two planes. The double axis actuator50will be described in detail with reference toFIGS. 3 to 6.

The double axis actuator50includes a mechanism having two functions built in a single casing510. The casing510, as known fromFIG. 5, includes three parts, that is, a main case body520, an upper lid body511which covers the upper surface of the main case body520, and a lower bottom plate body512which covers the lower surface of the main case body520.

The main case body520is plane-shaped, and has a peripheral wall521having a rectangular shape that is long in the front and back direction. The inside of the peripheral wall521is divided into upper and lower portions520aand520bby an intermediate wall522. In the center portion in the left and right direction of the front end portion of the peripheral wall521, a large notch portion521awhich opens downward is formed. On the upper end portions near the back ends on left and right sides of the peripheral wall521, attachment pieces521,521bprotruding outward are formed, and insertion holes521c,521care formed in the attachment pieces521b,521b. Further, in positions on the front end surface of the peripheral wall521, between which the notch portion521ais formed, and in positions on a back end surface which are nearly equally spaced left and right, engagement projections521d, . . . having upward facing engagement surfaces are provided (the projections formed on the back end surface are not shown). Further, in two places on each of the left and right side surfaces of the peripheral wall521, which are spaced back and forth, engagement projections521e,521ehaving downward facing surfaces are provided (only projections formed on one side surface are shown).

A central mount523of which the upper end is nearly the same in height as the upper end of the peripheral wall521is protruded in a position a little toward the back from the center in the front and back direction of the intermediate wall522. Engagement grooves524,524are formed, continuously extending from both side surfaces of the central mount523to the bottoms surface of the intermediate wall522and the inner surface of the peripheral wall521.

Sliding projected-rims525,525which are formed in cross section in the shape of a gate and are lower in protrusion height from the intermediate wall522than the central mount523are formed, extending from the both side portions of the front surface of the central mount523toward the front end of the main case body520. Between these sliding projected-rims525,525and the side surfaces of the peripheral wall521, sliding spaces520c,520care formed. Between the sliding projected-rims525and525, projection walls526,526protruded from the intermediate wall522are provided, coming close to the sliding projected-rims525,525. Between these projection walls526,526and the sliding projected-rims525,525, sliding grooves520d,520dare formed; and between the two projection walls526and526, a spring set space520eis formed. The back end of the projection wall526,526is located considerably apart from the central mount523.

In a position a little at the back of the central mount523, two thickish support cylinders527,527arranged right and left are protruded upward from the intermediate wall522. Further, between these support cylinders527,527and the central mount523, and in positions near the side surfaces of the peripheral wall521, thinnish support cylinders528,528are protruded upward from the intermediate wall522. On a concentric circle about each of the thickish support cylinders527,527, . . . , three facing holes527a,527a. . . , are formed. Further, four insertion holes527b,527b. . . , are respectively formed on a concentric circle inside the position where the facing holes527a,527a. . . are formed.

In positions corresponding to the sliding spaces520c,520con the inner surface of the back end portion of the peripheral wall521, reception parts529,529are projected. On the upper surfaces of the reception parts529,529, reception surfaces529a,529awhich open upward and dent in the shape of a semicircle are formed.

The lid body511includes a plate-shaped main part511awhich has such the size as to cover the upper surface of the main case body520entirely and the shape of a rectangle which is long back and forth, and a peripheral wall part511bwhich protrudes downward from the peripheral edge of the main part511a. In a position near the front end of the main part511a, there is formed an insertion hole511chaving the shape of an ellipse that is long in the front and back direction. In positions near the back end of the peripheral wall part511b, there are formed attachment pieces511d,511dprotruding outward from the lower end portion. In the attachment pieces511d,511d, insertion holes511e,511eare formed. Further, in positions at the upper end of the peripheral wall511bwhich are spaced back and forth, engagement pieces511f,511f, . . . (only one sided-engagement pieces are shown) are protruded downward. In these engagement pieces511f,511f, . . . , engagement holes511g,511g, . . . are formed.

When the upper lid body511is located so as to cover the upper surface of the main case body520, the elliptic insertion hole511cis located in a position corresponding to the space between the sliding projected-rims525and525formed in the main case body520, and the attachment pieces511d,511dare superimposed on the attachment pieces521b,521bof the main case body520. Further, the insertion holes511e,511eare put in a superimposed state on the insertion holes521c,521cformed in the attachment pieces521,521bof the main case body520. The lower edges of the engagement holes511g,511g, . . . of the engagement pieces511f,511f, . . . engage with the downward facing engagement surfaces of the engagement projections521e,521e, . . . formed on the peripheral wall521of the main case body520, whereby drop-out of the upper lid body511from the main case body520is prevented.

The lower bottom plate body512includes a main part512aformed in the shape of a rectangular plate which is longer a little in the front and back direction than the size covering entirely the lower surface of the main case body520, and a peripheral wall part512bwhich protrudes upward from the slight inside of the peripheral edge of the main part512aand is short. In positions at the front end of the main part512awhich are spaced left and right, two engagement pieces512c,512care protruded upward. In these engagement pieces512c,512c, engagement holes512d,512dare formed. Further, at a back end position of the main part512a, which is backward apart a little from the back end portion of the peripheral wall part512b, an engagement wall512eis installed upright. On a front surface of this engagement wall512e, three engagement projections512f,512f,512fof which engagement surfaces face downward are provided, which are spaced right and left.

The lower bottom plate body512is located so as to cover the lower surface of the main case body520, the upper edges of the engagement holes512d,512dof the engagement pieces512c,512cof the lower bottom plate body512engage with the upward facing engagement surfaces of the engagement projections521d,521sformed on the front surface of the peripheral wall521of the main case body520, and the downward facing engagement surfaces of the engagement projections512f,512f,512fformed on the rear engagement wall512eengage with the upward facing engagement surfaces of the engagement projections521d,521d,521dformed on the back surface of the peripheral wall521of the main case body520. Hereby, drop-out of the lower bottom plate body512from the main case body520is prevented.

As described above, the upper lid body511is coupled to the main case body520so as to cover the upper surface of the main case body520, and the lower bottom plate body512is coupled to the main case body520so as to cover the lower surface of the main case body520, whereby the casing510is formed. Between the intermediate wall522of the main case body520and the upper lid body511, a mechanism arrangement space510ais formed; and between the intermediate wall522of the main case body520and the lower bottom plate body512, a circuit arrangement space510bis formed. As known fromFIG. 3, the inside of the case body510has left and right symmetrical inner structure with a plane passing through a center line by which the casing510is divided into left and right parts and extending in the vertical direction.

In the circuit arrangement space510b, a circuit board530on which a control circuit is constituted is arranged. On the circuit board530, electronic parts are mounted. Onto the center portion in the left and right direction on the upper surface of the front end portion of the circuit board530, a connector531is attached, and the connector531is faced outward from the notch part521aformed in the front surface portion of the peripheral wall521of the main case body520. Further, in the circuit board530, in positions corresponding to the downsides of the support cylinders527,527formed on the main case body520, insertion holes532,532are formed. On a concentric circle about each of the insertion holes532,532, three Hall elements533,533, . . . are mounted. Further, four insertion holes534,534, . . . are formed on a concentric circle inside the position where the Hall elements533,533, . . . are arranged. The Hall elements533,533, . . . are arranged opposed to the facing holes527a,527a, . . . formed in the intermediate wall522of the main case body520, and the insertion holes534,534, . . . are arranged opposed to the insertion holes527b,527b, . . . formed in the intermediate wall522of the main case body520. Further, tall electronic parts539,539, . . . arranged on the circuit board530are mounted so as to be located in tall space of the downside of the central mount523formed in the main case body520.

In the mechanism arrangement space510aof the casing510, a mechanical part is arranged. Since the inside of the casing510is divided into the circuit arrangement space510bwhere the circuit board530is arranged and the mechanism arrangement space510awhere the mechanical part is arranged, it is possible to prevent shavings of each member which are produced from the mechanical part, and oil from affecting the circuit board530. Therefore, it is possible to elongate the life of the circuit board530.

The mechanical part includes an output part540, a drive source550, and a drive power transmission part560which transmits drive power of the drive source550to the output part.

The output part540includes an output gear541, a slide base542, and a compression coil spring543. The output gear541is formed by integrally forming an early cylindrical coupling part541aand sector gear parts541b,541bthat protrude from the lower end portion of the coupling part541ain the opposite directions to each other. On the peripheral surface of the upper end portion of the coupling part541a, engaging projected rims541c,541c, . . . are formed at intervals in the peripheral direction.

In the slide base542, a cylindrical fitting part542bis protruded upward from the center of the upper surface of a plate-shaped base542a, and two plate-shaped sliding legs542c,542care protruded downward from the lower surface of the base542a, apart right and left from each other. Between back end portions of the two sliding legs542c,542c, a not-shown reception plate is formed. In such the slide base542, the sliding legs542c,542care slidably engaged with the sliding grooves520d,520dof the main case body520, and the not-shown reception plate formed between the back end portions of the sliding legs542c,542cis located in the space between the projection walls526,526of the main case body520and the central mount523. Till the slid base542moves to the front end in the moving range, the reception plate does not collide with the back ends of the projection walls526,526. The compression coil spring543is arranged in the spring set space520eof the main case body520, and is put in a compressed state between the reception plate of the slide base542and the inner surface of the front end portion of the peripheral wall521of the main case body520. Therefore, the slide base542is energized backward by the compression coil spring543.

As described above, the coupling part541aof the output gear541is fitted at the outside of the fitting part542bof the slide base542arranged in the mechanism arrangement space510aof the casing510. Hereby, the output gear541(as an output shaft) moves together with the slide base542in the front and back direction, and is supported by the slide base542rotatably around an axis of the fitting part542b.

The drive sources550,550are constituted as brushless motors. Since the two brushless motors550,550have the same structure, only one will be described. To the support cylinder527protruded from the intermediate wall522of the main case body520, an insulator551is fixed in a fitting state at the outside of the support cylinder527. The lower end portions of four terminals552,552, . . . supported by the insulator551are inserted into the insertion holes527b,527b, . . . formed in the intermediate wall522, and protruded into the circuit arrangement part510b. Further, the lower end portions of the terminals552,552, . . . are inserted into the insertion holes534,534, . . . of the circuit board530, and connected at the back side of the circuit board530to a predetermined connection land (not shown) by soldering. A core553is fixed onto the main case body520so as to be located outside the insulator551, and a not-shown coil is wounded around the core553. To the coil, the electric power is supplied through the terminals552,552, . . . . The insulator551, the terminals552,552, . . . , the core553, and the coil constitute a stator part of the brushless motor550.

To the support cylinder527, a bearing metal554is fixed in a fitting state at the inside of the support cylinder527, and a shaft555is rotatably supported by the bearing metal554. To the upper end portion of the shaft555, a rotor member556is fixed, and a pinion gear557is integrally formed in the center portion of the upper surface of the rotor member556. A reference numeral558is a rotor magnet which is formed nearly in the cylindrical shape and magnetized alternately in the peripheral direction, and its upper end portion is fixed onto the peripheral portion of the rotor member556. Hereby, the rotor magnet558is located so as to surround the core553at the outside, and the lower end portion of the rotor magnet558is opposed to the Hall elements533,533,533on the circuit board530through the facing holes527a,527a,527aformed in the intermediate wall522of the main case body520.

Therefore, the electric power is applied through the terminals552,552, . . . to the coil wound around the core553, rotational power is produced in the rotor magnet558, and the rotor constituted by the rotor magnet558, the rotor member556and the shaft555rotates.

The drive power transmission part560is arranged in left and right pairs. Since the left and right parts have the entirely same constitution except that they have the shapes of left-right surface symmetry, only one part will be described.

The drive power transmission part560has a rack member561, which is arranged in the sliding space520cof the casing510movably in the front and back direction. The rack member561forms a rectangular body which is long in the front and back direction, and has rack tooth561aformed on one side surface. This rack member561is a movable part which is moved by the drive source550, and it is necessary for the drive part to include this rack member561that is the movable part and the drive source550. In the rack member561, force-fit holes561b,561bwhich open to a back end are formed up and down. A force-fit part562ais formed at the front end portion of a lead screw562, and the force-fit part562ais forced into the lower force-fit hole of the rack member561. Hereby, to the front end portion of the lead screw562, the rack member561is fixed. In the lead screw562, screw threads562bare formed in most of the portions except for the force-fit part562a. As described above, since the force-fit holes561b,561bare formed in the rack member561up and down in two stages, the rack members561,561used right and left can have the same structure. Namely, even in case that the rack member561is coupled to the lead screw562at the position biased downward, by arranging rack members to be arranged left and right in left-right symmetry, the same rack member561can be used left and right.

The lead screw562is fed by a cylindrical gear563in the front and back direction. The cylindrical gear563is formed in the shape of a cylinder that is long in the front and back direction. The cylindrical gear563has a drop-out preventing projection563aformed on the peripheral surface of its front end portion; a large-diameter part563bthat is large in outer diameter, and is formed in a slightly backward position of the drop-out preventing projection563a; and a helical gear563cformed on the back side of the large-diameter part563b. On the inner surface of the cylindrical gear563, a thread groove563dis formed.

A ball bearing564is fitted at the outside of the front end portion of the cylindrical gear563. In the ball bearing564, plural balls564c,564c, . . . are sealed between an inner race564aand an outer race564b, and the outer race564band the inner race564aare constituted so that they can rotate mutually. The inner race564ais fitted at the outside of the cylindrical gear563between the drop-out preventing projection563alocated at the front end of the cylindrical gear563and the large-diameter part563b. Hereby, drop-out of the ball bearing564from the cylindrical gear563is prevented.

The screw thread562bof the lead screw is tightened into the thread groove563dof the cylindrical gear563, the outer race564bof the ball bearing564is engaged into the engagement groove524formed from the central mount523of the casing510to the inner surface of the peripheral wall521, and the back end portion of the cylindrical gear563is accepted by the reception surface529aof the reception part529formed on the back end portion inner surface of the peripheral wall521of the main case body520. Hereby, the cylindrical gear563is rotatably arranged in the casing510.

Reference numeral565is a transmission gear, and the same transmission gears565,565are used left and right. Therefore, only one transmission gear565will be described. The transmission gear565transmits rotation of the brushless motor550to the cylindrical gear563. The transmission gear565is formed by integrally forming a flat gear565aand a cylindrical worm gear565bwhich is protruded downward from the downside of the center portion of the flat gear565a. The worm gear565bis rotatably fitted at the outside of the support cylinder528provided upright on the intermediate wall522of the main case body520. The worm gear565bis engaged with the helical gear563cof the cylindrical gear563, and the flat gear565ais engaged with the pinion gear557of the motor550.

In the thus-constituted double axis actuator50, the screws570,570inserted from the downside into the insertion holes511e,511e,521c,521cof the attachment pieces511d,511d,521b,521bare tightened into not-shown thread holes in the attachment pieces43c,43cprotruded on both sides of the back end portion of the lower support piece43of the bracket40, thereby to be fixed on the downside of the lower support piece43of the bracket40. The coupling part541aof the output gear541of the output part540is fitted at the inside of the engagement recess part38aof the coupling boss38of the lamp unit30which is engaging with the thrust metal43bsupported by the lower support piece43of the bracket40. Further, the engaging projected-rims541c,541c, . . . protruded on the upper end portion peripheral surface of the coupling part541aare engaged with not-shown engagement notches formed in the inner surface of the engagement recess part38a, so that the coupling boss38and the coupling part541aof the output gear541cannot freely rotate mutually. Further, in the coupling boss38and the coupling part541aof the output gear541, the mutual axis-down can be produced at a slight angle by tolerance on manufacture.

As a light source of the lamp unit30, the discharge bulb32is used. Therefore, at the lower portion inside the lamp body22, the discharge bulb switching circuit60for switching on the discharge bulb32is arranged. To the leading end of a code61extending from the discharge bulb switching circuit60, a bulb socket62is connected, and the bulb socket62is connected to the discharge bulb32. Accordingly, the lighting voltage generated in the discharge bulb switching circuit60is applied through the bulb socket62to the discharge bulb32, whereby the discharge bulb32is switched on.

Action of the above automotive headlamp10will be described below.

In the automotive headlamp10, when the beam irradiation direction is adjusted in the time of forwarding from a manufactory or in the time of an automobile inspection, the adjusting shafts49b,49bof the two space adjusters49,49are appropriately operated, and the bracket40supporting the lamp unit30is tilted up-and-down and left-and-right, whereby the beam irradiation direction is adjusted.

The adjustment of the beam irradiation direction during running is performed by driving the double axis actuator50.

In case that the beam irradiation direction is tilted in the vertical direction, the two motors550,550are driven so that the two rack members561,561move in the same phase, that is, so that the two rack members561,561move forward or backward together. As the motors550,550are driven, the rotation of the rotor magnets558,558are transmitted through the pinion gears557,557to the flat gears565a,565aof the transmission gears565,565, and the helical gears563c,563cof the cylindrical gears563,563are fed by the worm gears565b,565bwhich rotate together with the flat gears565a,565a, whereby the cylindrical gears563,563rotate. As the cylindrical gears563,563rotate, the screw threads562b,562bof the lead screws562,562engaged into the thread grooves563d,563dof the cylindrical gears563,563are fed in the front and back direction. Therefore, the rack members561,561fixed to the front end portions of the lead screws562,562are moved forward or backward in the sliding spaces520c,520c. Since the two rack members561,561are moved forward or backward together, the output gear541in which the sector gear portions541b,541bengage with the rack teeth561a,561aof the rack members561,561is moved forward or backward.

As the output gear541of the double axis actuator50is thus moved forward or backward, the coupling boss38of the lamp unit30which is fitting to the coupling part541aof the output gear541is moved forward or backward along the thrust metal43bsupported by the bracket40. Accordingly, the lamp unit30is tilted, with a portion where the self-aligning metal37supported by the shaft36is supported by the upper support piece42of the bracket40and the metal holder47thereof as a rotational fulcrum, along the vertical surface on which a line connecting the axis of the shaft36and the axis of the coupling boss38is located, where the optical axis x-x of the lamp unit30is located, that is, tilted in the upward direction or the downward direction.

When the beam irradiation direction is rotated in the left and right direction, the two motors550,550are driven so that the two rack members561,561move in reversed phase, that is, so that one rack member561moves forward and the other rack member561moves backward. The drives of the two motors550,550appear as the movements of the rack members561,561through the above transmission paths. By the movements of the left and right rack members561,561in the opposite directions to each other, the output gear541rotates without moving in the front and back direction. By the rotation of the output gear541, the lamp unit30of which the coupling boss38is fitting to the coupling part541aof the output gear541rotates around the axis along the plane orthogonal to the axis connecting the shaft36and the coupling boss38. Hereby, the lamp unit30is rotated in the left and right direction. Accordingly, the lamp unit30can be rotated, regardless of the rotating positions along the two planes, along each plane. Namely, in the middle of tilting in the vertical direction, the lamp unit30can be rotated in the left and right direction; and in the middle of rotation in the left and right direction, the lamp unit30can be tilted in the vertical direction.

FIG. 7shows a modified example70of the double axis actuator. This double axis actuator70is different from the double axis actuator50only in a part of the output part and a part of the drive power transmission part, and it is similar to the double axis actuator50in others than the above points. Therefore, here, the points in which the double axis actuator70is different from the double axis actuator50will be mainly described, and description of other points is omitted.

A casing510of the double axis actuator70is the same as the above casing510.

An output part740has a slide base542and a compression coil spring543which are similar to those in the output part540. Though an output gear741is also nearly similar to the output gear541, it has arm parts741b,741bprotruding from side surfaces of a coupling part741ato the left and right in place of the sector gear parts541b,541b. In end portions of the arm parts741b,741b, coupling holes741d,741dthat are elongated in the left and right direction are formed. At the outside of a fitting part542bof a slide base542housed in the casing510slidably in the front and back direction, the coupling part741aof the output gear741is fitted, whereby the output gear741is rotatably supported by the slide base742.

A drive power transmission part760has, in place of the rack member561of the drive power transmission part560of the double axis actuator50, a coupling member761as a movable part. In the coupling member761, a main part761aand a coupling pin761bprotruded from the main part761aupward are integrally formed, and the main part761ahas a force-fit hole761cwhich opens to the back end surface. A force-fit part562aof a lead screw562which is similar to that in the double axis actuator50is forced into the force-fit hole761cof the main part761a. Hereby, the coupling member761is fixed to the front end portion of the lead screw762. In addition, the drive power transmission part760includes a cylindrical gear563, a ball bearing564, and a transmission gear565, which are similar to those in the double axis actuator50. Rotation of a drive source (brushless motor)550is converted into linear motion in the front and back direction of the lead screw562through the transmission gear565and the cylindrical gear563, so that the coupling member761fixed to the front end of the lead screw562is moved in the front and back direction. Further, the coupling pin761bof the coupling member761is engaged with the coupling hole741dof the arm part741bof the output gear741slidably. As described above, it is necessary for the drive part to include the drive source550and the coupling member761.

Therefore, when the two coupling members761,761move in the same phase, that is, in the same direction and by the same distance, the output gear741moves in the front and back direction without rotating. Further, when the two coupling members761,761move in reversed phase, that is, in the opposite directions and by the same distance, the output gear741rotates without moving in the front and back direction.

The coupling part741aof the output shaft741of the double axis actuator70is fitted in the inside of the fitting recess part38aof the coupling boss38of the lamp unit30, whereby the lamp unit30is coupled to the double axis actuator70, and tiled by the drive of the double axis actuator70along each of two planes that are orthogonal to each other.

FIG. 8shows an example80of a control circuit which controls the whole of a headlamp system including the lamp unit30.

The control circuit80includes an ECU81which controls the whole of a headlamp system including the lamp unit30. To the ECU81, an ignition switch81aand a lamp switch81bare connected. When the lamp switch81bis switched on in a state where the ignition switch81ais switched on, a lighting command is given from the ECU81to a lighting circuit82. Hereby, the discharge bulb33of the lamp unit30is switched on by the lighting circuit82, and beams having the predetermined luminous distribution patterns are applied ahead.

To the ECU81, signals from various sensors83are inputted. For example, signals from a steering sensor83a, a height sensor83b, a speed sensor83c, a wheel sensor83d, and a GPS sensor83eare inputted there. Information relating to a steering direction and a steering angle in steering operation are inputted from the steering sensor83a, information relating to the respective heights of front and back wheels are inputted from the height sensor83b, information relating to vehicle speed is inputted from the vehicle sensor835c, information relating to height of each wheel is inputted from the wheel sensor83d, and information relating to the present position on the basis of a global positioning system is inputted from the GPS sensor83e. The ECU81, on the basis of the information from each sensor83, feeds out the predetermined control signal to the double axis actuator50or70so that the irradiation direction becomes optimum, and the double axis actuator50or70receives the control signal from the ECU81through one connector531.

On the circuit board530, a CPU (Central Processing Unit)535into which a control program is set up is mounted, and the predetermined control signal is transmitted from the ECU81through the connector531to the CPU535. The CPU535, on the basis of the control signal obtained from the ECU81, transmits predetermined signals to respective driver circuits536,537constituted on the circuit board530, so that the two motors550,550are separately driven by each driver circuit536,537. The drive of the motors550,550moves the movable parts (rack members561,561or coupling members761,761), and the movement of the movable parts rotates and/or moves the output parts540,540(or740,740).

In the automotive headlamp10, the lamp unit30is coupled at one place, that is, at the coupling boss38, with the output part540or740(output shaft541or741of the output part540or740) of the double axis actuator50or70which is the drive unit. Therefore, one drive unit can be used in almost of all kinds of lamp units which are different in shape and size, and at least many kinds of lamp units. Further, since the double axis actuator can rotate the lamp unit30in each plane regardless of the rotational positions of the lamp unit30in the two planes, there is no limit in rotation control of the lamp unit30, so that beams can be applied in the desired direction.

Further, the lamp unit30is supported by the shaft36that is the support shaft rotatable and tiltable with respect to the housing20(through the bracket40), and the output part540or740(output shaft541or741of the output part540or740) is coupled to the portion located on the opposite side to the portion where the lamp unit30is coupled to the shaft36. By the rotation of the output part, a first drive mode in which the lamp unit30is rotated about the shaft36is formed. By the linear movement of the output part in a direction substantially orthogonal to the axial direction of the shaft36, a second drive mode in which the lamp unit30is tilted together with the shaft30is formed. Therefore, the support structure of the lamp unit30with respect to the housing20is simplified, which contributes to cost reduction.

Further, (the output shaft541or741of) the output part540or740is located on the vertical plane including the optical axis x-x of the lamp unit30. Therefore, the lamp units having the same structure can be used for right and left vehicle lamps, which contributes to the cost reduction.

Furthermore, the drive unit50or70includes the two drive sources550,550and the rack members561,561or the coupling members761,761which are two movable parts moved separately by the drive sources; both the two drive sources and the two movable parts are arranged in right and left symmetry with the vertical plane along the linear movement direction of the output part; the two movable parts are moved in reversed phase, whereby the output part rotates; and the two movable parts are moved in the same phase, whereby the output part moves linearly. Therefore, the driving units having the same structure can be used in the left and right lamp units, which contributes to the cost reduction.

Further, the automotive head lamp10has a failsafe function. Namely, in case that one of the two motors550,550breaks down, the other motor550is driven, whereby the rack member561or the coupling member761moved by the motor550is moved backward, and at least the lamp unit30can be tilted downward, so that it is prevented that a driver in a car running on the opposite lane is dazzled by the headlights.

One example of the failsafe function will be described with reference toFIG. 8.

For example, the CPU535is provided with an abnormality sensor538which detects abnormality that control of the predetermined position of the lamp unit30is impossible, an irradiation position sensor539which detects an irradiation position of the lamp unit30, and an abnormal time position controller540which drives one drive part which operates normally when the abnormality is produced.

As abnormality that the lamp unit30does not move to the predetermined irradiation position, there are, for example, trouble of the driver circuit536or537, trouble or lock of the motor550, and lock or breakdown of the movable part561or761. The abnormality sensor538, when, for example, the above abnormality is produced, detects its abnormality.

In case that the abnormality has detected by the abnormality sensor538, the irradiation position of the lamp unit30is detected by the irradiation position sensor539. In case that the lamp unit30is located in the predetermined irradiation position, that is, in an upper limit position where the glare is not given to a driver in a car running on the opposite lane and in a position below the upper limit position, the lamp unit30is left as it is. In case that the lamp unit30is located above the predetermined irradiation position, the abnormal time position controller540drives the drive part in which the abnormality is not produced, and controls the lamp unit30so that the irradiation position becomes the predetermined irradiation position and below. Namely, the rack member561or the coupling member761of the drive part which operates normally is moved backward.

The concrete operation of the above failsafe function will be described with reference toFIGS. 9(a) to9(c).FIGS. 9(a) to9(c) show center spot lights of luminous distribution patterns irradiated on a screen located forward of the vehicle. Namely, S1to S2show the irradiation position divided into six equal divisions in the vertical direction, wherein S1shows an uppermost irradiation position, and S6shows a lowermost irradiation position.

FIG. 9(a) shows an irradiation position changing operation in the normal time, in which both the position change in the vertical direction and the position change in the left and right direction are performed linearly as shown by arrows. In case that the position change in the vertical direction and the position change in the left and right direction are performed simultaneously, the spot light S moves obliquely.

FIG. 9(b) shows a case where abnormality is produced in the drive part on the right side in the running direction. In this case, the drive part on the left side is operated to control the irradiation position. By moving the left movable part561or761backward, the spot light S lowers toward the lower left. Further,FIG. 9(c) shows a case where abnormality is produced in the drive part on the left side in the running direction. In this case, the drive part on the right side is operated to control the irradiation position. By moving the right movable part561or761backward, the spot light S lowers toward the lower right. For example, inFIG. 9(b), in case that the glare is produced in upper areas from S5(glare area), the normal drive part is driven till the irradiation position becomes S6and below.

In the failsafe function, the irradiation position of the lamp unit30is also detected, and in the abnormal time, the lamp unit30is controlled so that its irradiation position becomes the predetermined position or below. However, in the abnormal time, by driving the normal drive part, the control to make the irradiation position as downward as possible may be performed. This comes from a though of preventing at least the glare.

In the above embodiment, the brushless motor is used as the drive source of the double axis actuator50,70. However, this does not mean that the drive source is limited to the brushless motor. Even in case that the motor is used as the drive source, for example, a DC (direct current) motor or a stepping motor can be used, or drive sources other than the motor can be also used.

FIGS. 10 to 12show a second exemplary embodiment in which the vehicle lamp is applied to the automotive headlamp.

Au automotive headlamp110has substantially the same structure as that of the automotive headlamp10. Namely, a lamp unit130similar to the lamp unit30is arranged in a lighting room121of a housing120, and the lighting room121is formed by covering the front of a lamp body122with a transparent cover123.

The lamp unit130is supported through a bracket140by the lamp body122tiltably in the vertical direction and in the right and left direction. However, the lamp unit130may be directly supported by the lamp body22rotatably in the vertical direction and in the right and left direction.

A double axis actuator90which is a drive unit is supported by the bracket140, and the lamp unit130supported by the bracket140rotatably in the vertical direction and in the right and left direction is coupled to an output part of the double axis actuator90.

Further, in the housing120, a discharge bulb switching circuit160is arranged, and the lamp unit130is switched on by the discharge lamp switching circuit160.

As known fromFIGS. 10 and 11, the lamp unit130includes a reflector131, a discharge bulb132supported by the reflector131, a coupling part133attached onto a front end of the reflector131, a projection lens134arranged so as to cover an opening located at a front end of the coupling part133, and a shade135provided for the coupling part133. The light which is emitted from the discharge bulb132and reflected by the reflector131is condensed in the vicinity of an upper edge135aof the shade135. The condensed light is projected forward by the projection lens134having a focus in the vicinity of the upper edge135aof the shade135, whereby a beam having the predetermined luminous distribution pattern is formed. The luminous distribution pattern has, on its upper edge, a cut-off line limited by the upper edge135aof the shade135.

From the upper surface of the coupling part133, a shaft136is protruded upward, and a self-aligning metal137is fitted at the outside of the shaft136. The self-aligning metal137has a peripheral surface137ahaving a substantially spherical shape, and a center hole137b, and the shaft136is inserted into the center hole137bslidably.

In a position of the lower surface of the coupling part133corresponding to the shaft136, a coupling boss138is projected. The coupling boss138has a substantially circular outer shape viewed in the vertical direction, and includes a fitting recess part138awhich opens to the lower surface. On the inner surface of the fitting recess part138a, not-shown plural engagement notches are provided.

A line connecting an axis of the shaft136and an axis of the coupling boss138is located on a vertical plane where an optical axis x-x of this lamp unit130is located.

The bracket140, as known fromFIGS. 10 and 11, includes a main part141formed in the shape of a saucer which opens forward and has a big opening141a, an upper support piece142which projects from the upper end of the main part141forward, a lower support piece143which projects from the lower end of the main part141forward, and coupling pieces144,145,146which project from three corner portions of the main part141.

In the center in the left and right direction of the front end portion of the upper support piece142, a support recess part142awhich dents forward is formed. The forward facing surface of the support recess part142ais formed in the shape of a concave spherical surface. On both sides of the front end surface of the upper support piece142with the support recess part142abetween, threaded holes142b,142bare formed. Onto the front end portion of the upper support piece142, a metal holder147is attached. In the center portion in the left and right direction of the metal holder147, a press part147athat dents backward is formed. The backward facing surface of the press part147ais formed in the shape of a concave spherical surface. On both sides of the metal holder147with the press part147abetween, screw insertion holes147b,147bare formed. Further, at the upper edge portion of the metal holder147, a regulating part147dwhich protrudes backward is formed. In a state where the metal holder147is brought into contact with the front end of the upper support piece142, and the regulating part147dcovers the upsides of the press part147aand the support recess part142a, screws147c,147cinserted from the front side into the screw insertion holes147b,147bare tightened into the threaded holes142b,142bof the upper support piece142, whereby the metal holder147is attached onto the front end portion of the upper support piece142. Hereby, between the support recess part142aof the upper support piece142and the press part147aof the metal holder147, a spherical reception concavity is formed.

In a position near the front end of the lower support piece143, an elongated hole43awhich is elongated in the front and back direction is formed. The nearly central portion in the front and back direction of this elongated hole143ais located in a position to which the position where the reception concavity is formed corresponds in up-down relation. Into the elongated hole143a, a thrust metal143cis fitted. The outer size of the coupling boss138is larger than a sliding groove143dwhich is formed in the thrust metal143cand is long back and forth.

The coupling boss138of the lamp unit130is placed on the thrust metal143csupported by the lower support piece143of the bracket140, and the self-aligning metal137fitted at the outside of the shaft136protruding from the upper surface of the lamp unit130is rotatably supported by the support recess part142aof the upper support piece142of the bracket140and the press part147aof the metal holder147. Hereby, the lamp unit130is supported through the bracket140by the lamp body122rotatably in two planes that are orthogonal to each other. Namely, the lamp unit130can rotate in the plane orthogonal to an axis connecting the shaft136and the coupling boss138around the axis. Further, by the front and back movement of the coupling boss138along the sliding groove143d, the lamp unit130can rotate in the plane including the axis connecting the shaft136and the coupling boss138and an axis passing through the center in the width direction of the sliding groove143dand extending back and forth.

The bracket140is supported by the lamp body122tiltably in the vertical direction and in the left and right direction. Further, since the attaching method of the bracket140to the lamp body122is similar to that in the automotive headlamp10, a drawing showing the attaching method and the description about the attaching method are omitted.

The above double axis actuator90is supported by the bracket140on the downside of the lower support piece143of the bracket140.

In the double axis actuator90, two drive parts and a single output part are arranged in a casing91. The casing91is constituted by the lower support piece143of the bracket140and a lower casing911fixed onto the lower surface side of the lower support piece143. The lower casing911is formed by integrally forming a motor arranging part911aand an output part arranging part911bextending from the front end of the motor arranging part911aforward. Onto the upper surface of the motor arranging part911awhich is nearly plate-shaped, two fulcrum recess parts911c,911care formed, which are spaced left and right. The output part arranging part911bwhich is nearly plate-shaped is located in a position which is slightly higher than the position of the motor arranging part911a, and has, in its center portion in the left and right direction, a sliding hole911dextending in the front and back direction. Further, in left and right end portions of the output part arranging part911b, attachment holes911e,911eare formed. From peripheral edges of the attachment holes911e,911e, collars911f,911fare protruded upward. Further, from the center portion in the left and right direction of the front end of the output part arranging part911b, a stopper911gis protruded upward. The stopper911ghas a projection911hwhich protrudes backward.

Attachment screws911i,911iinserted from the downside into the attachment holes911e,911eof the lower casing911are tightened into not-shown threaded holes formed on the lower surface of the lower support piece143of the bracket140. Hereby, the lower casing911is fixed to the bracket140, and the collars911f,911fkeep the space between the lower casing911and the lower support piece143of the bracket140at the predetermined value. Thus, the casing91of the double axis actuator90is formed.

In the above casing91, a single output part92and a left and right pair of drive parts93L,93R are arranged.

The output part92is formed by integrally forming an output shaft921coupled to the coupling boss138of the lamp unit30, coupling wings922L,922R to which the drive parts93L,93R are coupled, and a guided part923which engages with the sliding hole911dof the casing91slidably.

The output shaft921forms the cylindrical shape of which an axial direction extends up and down. On the peripheral surface of upper half portion of the output shaft921, plural engaging projected-rims are formed, extending in the vertical direction. A lower end portion921bof the output shaft921is larger in diameter than other portions.

The coupling wings922L,922R continue from the lower end of the output shaft921integrally, wherein the coupling wing922L protrude to the left and the coupling wing922R protrude to the right. On each of coupling wings922L,922R, a recess part922aof which the upper surface is opened is formed. From the nearly central portion of the recess part922a, a joint part922bis protruded. Inside the joint part922b, a dome-shaped space922cis formed, which has an opening922dat its back. Of a peripheral wall922edefining the space922a, in a position opposed to the back opening922dof the joint part922b, a notch922fis formed. In the front surface of the center portion where the two coupling wings922L and922R are coupled, a recess part which opens forward is formed, and the back surface of the recess part becomes an abutment surface922g.

The guided part923forms the nearly cylindrical shape, and its outer diameter is nearly equal to the width of the sliding hole911dformed in the lower casing911. At the lower end of the guided part923, a drop-out preventing plate923ais formed.

In the output part92, its guided part923is engaged with the sliding hole911dof the lower casing911slidably. The output shaft921is inserted from the downside into the sliding groove143dof the thrust metal143cfitted into the elongated hole143aof the lower support piece143of the bracket140, and fitted into the fitting recess part138aof the coupling boss138of the lamp unit130. At this time, the engaging projected-rims921aof the output shaft921engaged with not-shown plural engagement notches formed on the inner surface of the fitting recess part138a. Further, a leading end138cof a spring138battached to the coupling boss138is laid between the output shaft921and the wall surface of the fitting recess part138a, thereby to absorb play between the output shaft921and the fitting recess part138a. Between the output part92and the casing91, a compression coil spring924for energizing the output part92backward is inserted. Namely, a disc-shaped contact part925aof a contact member924, from the front surface of which a bearing shaft925bprotrudes, is brought into contact with the abutment surface922gformed on the front surface of the output part92. At the outside of the bearing shaft925bof the contact member925in such the state, the back end portion of the compression coil spring924is fitted. Further, the front end portion of the compression coil spring924is fitted at the outside of the projection911hof the stopper911gprovided at the front end portion of the lower casing911, whereby the compression coil spring924is put in a compressed state between the stopper911gand the output part92. By this compression coil spring924, the output part92is energized backward, whereby the play in the front and back direction is absorbed.

Though the two drive parts93L and93R are different in arrangement position, they have the same structure. Namely, the drive part93has a linear motor931as a drive source, and a spherical part932as a movable part. The linear motor931is so constituted that a movable shaft933moves in the front and back direction by drive of the linear motor931. The spherical part932is formed integrally at the front end of the movable shaft933. In positions near the front end of an outer case931aof the linear motor931, fulcrum shafts931b,931cprotruding up and down are formed. The upper fulcrum shaft931bof the linear motor931is rotatably fitted into a fulcrum recess part143bformed on the back lower surface of the lower support piece143of the bracket140, and the lower fulcrum shaft931cof the linear motor931is rotatably fitted into the fulcrum recess part911cformed in the motor arrangement part911aof the lower casing911. Hereby, the linear motor931is supported in the motor arrangement part911aswingably in the left and right direction. Further, the spherical part932is fitted into the dome-shaped space922cinside the joint part922bof the output part92in a rotatable state. The movable shaft933extends backward through the back opening922of the joint part922band the notch922fformed in the peripheral wall922e. As described above, the two drive parts93L,93R and the output part92are linked to each other.

Next, the operation of the double axis actuator90will be described referring mainly toFIGS. 12(a) to12(e).FIGS. 12(a),12(b), and12(c) show states where a beam is applied toward the center in the left and right direction,FIG. 12(d) located on the left side shows a state where a beam is applied to the left, andFIG. 12(e) located on the right side shows a state where a beam is applied to the right.FIGS. 12(a), (d) and (e) located in the middle stage show a state where a beam is applied to the upper limit position where the glare is not produced.

As described above,FIG. 12(a) shows the state where the beam is applied toward the center in the left and right direction and to the upper limit position where the glare is not produced. In this state, the movable shafts933and933of the left and right movable parts93L and93R protrude from the linear motors931,931by the same length. Accordingly, the coupling wings922L,922R of the output part92are located in the same position in the front and back direction. In case that the irradiation position is changed from this state ofFIG. 12(a) to the upward position, the movable shafts933and933of the left and right movable parts93L and93R are protruded more from the linear motors931,931by the same length (state ofFIG. 12(b)). Further, in case that the irradiation position is changed from the state ofFIG. 12(a) to the downward position, the movable shafts933and933of the left and right movable parts93L and93R are pulled into the linear motors931,931by the same length (state ofFIG. 12(c)). In case that the irradiation position is changed from the above state ofFIGS. 12(a),12(b) or12(c) to the left, the movable shaft933of the left movable part93L is pulled into the linear motor931, and the movable shaft933of the right movable part93R is protruded more from the linear motor931(state ofFIG. 12(d)). Hereby, the leading end of the left coupling wing922L moves backward, and the leading end of the right coupling wing922R moves forward. Therefore, the output shaft921formed integrally with the coupling wings922L,922R rotates counterclockwise, and the lamp unit130coupled to this output shaft921is tiled to the left. At this time, the distance between the joint parts922b,922bof the coupling wings922L,922R becomes narrow in the arrangement direction of the linear motors931,931. Therefore, since the spherical parts932,932of the drive parts93L,93R come close to each other in the arrangement direction of the linear motors931,931, the linear motors931,931tilt around their fulcrum shafts931b,931cso that their front ends come close to each other. In case that the irradiation position is changed from the above state ofFIGS. 12(a),12(b) or12(c) to the right, the movable shaft933of the right movable part93R is pulled into the linear motor931, and the movable shaft933of the left movable part93L is protruded more from the linear motor931(state ofFIG. 12(e)). Hereby, the leading end of the right coupling wing922R moves backward, and the leading end of the left coupling wing922L moves forward. Therefore, the output shaft921formed integrally with the coupling wings922L,922R rotates clockwise, and the lamp unit130coupled to this output shaft921is tiled to the right. At this time, the distance between the joint parts922b,922bof the coupling wings922L,922R becomes narrow in the arrangement direction of the linear motors931,931. Therefore, since the spherical parts932,932of the drive parts,93L,93R come close to each other in the arrangement direction of the linear motors931,931, the linear motors931,931tilt around their fulcrum shafts931b,931cso that their front ends come close to each other.

The double axis actuator90in the automotive headlamp10according to the second exemplary embodiment absorbs, by swinging of the linear motors931,931, deviation in the arrangement direction of the linear motors931,931(states inFIGS. 12(d),12(e)) which is produced in the left and right ends of the output part92by the rotation of the output part92. Therefore, without applying bending stress to the movable shafts933,933, the poor operation and generation of the play can be reduced.