Leveling actuator and vehicle lamp fitting

Abstract

To provide a leveling actuator which enables accurate positioning of a shaft in an axial direction while having a simple structure.SOLUTION: A leveling actuator includes: a shaft 12 supported slidably in an axial direction; a holder 11 which holds the shaft 12 slidably in the axial direction in a state that the tip side of the shaft 12 protrudes from a hole part 15 at the front; and a rotary motor 13 which is held from the back side of the shaft 12 to the inner side of the holder 11 in a state that a male screw part 28 provided at a rotary shaft 27 is threadedly engaged with a female screw part 21 provided along the center axis of the shaft 12. The rotary motor 13 is a brushless DC motor and the shaft 12 is positioned in the axial direction by rotation control of the brushless DC motor.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a leveling actuator and a vehicle lamp.

Background Art

[0002] Conventionally, in vehicle lamps such as vehicle headlamps, a lamp unit that irradiates light toward the front of the vehicle is disposed inside a lamp body composed of a housing having an open front surface and an outer lens that covers the opening of the housing, and there is a lamp unit that irradiates light toward the front of the vehicle. Some are provided with an optical axis adjustment mechanism for adjusting the optical axis of the light irradiated from the lamp unit toward the front of the vehicle (see, for example, Patent Document 1 below).

[0003] In such a vehicle lamp provided with an optical axis adjustment mechanism, the optical axis of the light irradiated from the lamp unit toward the front of the vehicle is adjusted by an aiming operation for adjusting the inclination of the lamp unit in the left-right direction and the inclination in the up-down direction.

[0004] Further, after detecting the inclination of the vehicle in the front-rear direction, the optical axis of the light irradiated from the lamp unit toward the front of the vehicle is automatically adjusted in the up-down direction by a leveling operation to correct the fluctuation of the optical axis accompanying the change in the posture of the vehicle. It is also being done.

[0005] For example, Patent Document 1 below discloses a vehicle headlamp device including an optical axis deflection means for deflecting the irradiation optical axis of a vehicle headlamp. The optical axis deflection means includes a drive motor as a rotation drive source, and a plurality of detection elements for detecting the rotation position of the drive motor. And motor drive means for controlling the rotation operation of the drive motor based on the rotation position of the drive motor detected by the detection element. When an abnormality occurs in some of the plurality of detection elements, the motor drive means includes a rotation state recognition means for recognizing the rotation position of the drive motor based on the detection outputs of the remaining plurality of detection elements and a predetermined angle prediction time calculated from the rotation cycle of the drive motor. A vehicle headlamp device is disclosed.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] By the way, in the invention described in the above-mentioned Patent Document 1, in order to make both the swivel mechanism and the leveling mechanism compatible, a complex mechanism using a plurality of gears is adopted, and the number of parts is also increased.

[0008] Further, in the leveling actuator provided in the optical axis adjustment mechanism, the rotational drive of the rotary motor is converted into the slide drive of the shaft, and the inclination of the lamp unit connected via the tip side of the shaft and the pivot portion is adjusted.

[0009] In such a leveling actuator, when a stepping motor or the like is used for the rotary motor, it is difficult to position the shaft by controlling the rotation of the rotary motor, and a sensor or the like for detecting the position of the shaft in the front-rear direction is required. Therefore, also in this case, not only does the structure become complicated, but also the number of parts increases.

[0010] The present invention has been proposed in view of such conventional circumstances, and an object thereof is to provide a leveling actuator that has a simple configuration and enables accurate positioning of a shaft in the axial direction, and a vehicle lamp equipped with such a leveling actuator.

Means for Solving the Problems

[0011] In order to achieve the above object, the present invention provides the following means. 〔1〕 A leveling actuator for adjusting the optical axis of light irradiated from a lamp unit of a vehicle lamp in which the lamp unit is disposed inside a lamp body toward the front of the vehicle, A shaft that is supported slidably in the axial direction with the tip side connected to the lamp unit via a pivot part, a holder that holds the shaft slidably in the axial direction with the tip side of the shaft protruding from a front hole part, a rotary motor that is held inside the holder from the back side of the shaft in a state where a male screw part provided on a rotary shaft is screwed into a female screw part provided along the central axis of the shaft, wherein the rotary motor is a brushless DC motor, a leveling actuator characterized by positioning the shaft in the axial direction by rotation control of the brushless DC motor. 〔2〕 The leveling actuator according to 〔1〕 above, wherein the brushless DC motor is an outer rotor type. 〔3〕 The shaft has a wheel part protruding in a ring shape from the outer peripheral part on the rear end side, and a guide protrusion protruding from the outer peripheral part of the wheel part, the holder has a guide slit that axially notches the outer peripheral part from the rear end side, The leveling actuator according to 〔1〕 above, wherein the shaft is slid in the axial direction by slidably guiding the guide protrusion engaged with the guide slit in the axial direction with the wheel part fitted inside the holder. 〔4〕 The leveling actuator according to 〔3〕 above, wherein the holder has a connecting part connected between outer peripheral parts so as to straddle the opening end side of the guide slit. 〔5〕 The rotary motor has a positioning convex part on the surface facing the wheel part, The leveling actuator according to 〔3〕 above, wherein a position where the wheel part abuts against the positioning convex part is set as an initial position of the shaft. 〔6〕 A vehicle lamp including the leveling actuator according to any one of 〔1〕 to 〔5〕 above.

Advantages of the Invention

[0012] As described above, according to the present invention, there are provided a leveling actuator that has a simple configuration and enables accurate axial positioning of a shaft, and a vehicle lamp equipped with such a leveling actuator.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings used in the following description, for ease of viewing each component, the scale of the dimensions may be varied depending on the component, and the dimensional ratios of each component are not necessarily the same as the actual ones.

[0015] As an embodiment of the present invention, for example, a vehicle lamp 1 shown in FIGS. 1 to 5 will be described. Note that FIG. 1 is a front view showing the configuration of a vehicle lamp 1 including a leveling actuator 5. FIG. 2 is a cross-sectional view of the vehicle lamp 1 taken along line A-A shown in FIG. 1. FIG. 3 is a perspective view of the leveling actuator 5 as viewed from the front side. FIG. 4 is an exploded perspective view of the leveling actuator 5 as viewed from the front side. FIG. 5 is a cross-sectional view showing the structure of the leveling actuator 5.

[0016] In the following drawings, an XYZ orthogonal coordinate system is set, and the X-axis direction is the front-rear direction (length direction) of the vehicle lamp 1, the Y-axis direction is the left-right direction (width direction) of the vehicle lamp 1, and the Z-axis direction is the up-down direction (height direction) of the vehicle lamp 1, and they are respectively shown as such.

[0017] The vehicle lamp 1 of the present embodiment is, for example, an application of the present invention to a vehicle headlamp (headlamp) mounted on both corner portions on the front end side of a vehicle (not shown).

[0018] Specifically, as shown in FIG. 1, the vehicle lamp 1 has a structure in which a lamp unit that irradiates light toward the front of the vehicle (+X-axis direction) is disposed inside a lamp body composed of a housing 2 having an open front surface and a transparent outer lens that covers the opening of the housing 2.

[0019] In addition, in FIG. 1, the illustration of the outer lens constituting the lamp body, the lamp unit disposed inside the lamp body, and the like is omitted. Further, the shape of the lamp body is not particularly limited, and can be appropriately changed according to the design of the vehicle lamp 1 and the like.

[0020] The lamp unit includes, for example, a light source composed of a light-emitting diode (LED) that emits white light (hereinafter simply referred to as light), and a reflector that reflects the light emitted from the light source, and is configured to irradiate the light reflected by the reflector toward the front of the vehicle.

[0021] The lamp unit irradiates light that forms a low-beam light distribution pattern including a cut-off line at the upper end toward the front of the vehicle as a passing beam (low beam). Or, as a driving beam (high beam), it irradiates light that forms a high-beam light distribution pattern above the low-beam light distribution pattern toward the front of the vehicle.

[0022] Note that the lamp unit is not necessarily limited to a configuration in which the light reflected by the above-described reflector is irradiated forward of the vehicle. For example, a configuration in which the light emitted from the light source is irradiated forward of the vehicle using a lens may also be used.

[0023] In addition to the above-described LEDs, for the light source, a light-emitting element such as a laser diode (LD) can be used. Further, the number of light-emitting elements is not limited to one, and a plurality of light-emitting elements may be used.

[0024] The vehicle lamp 1 of the present embodiment includes an optical axis adjustment mechanism 3 for adjusting the optical axis of the light irradiated from the lamp unit forward of the vehicle.

[0025] In the vehicle lamp 1 provided with the optical axis adjustment mechanism 3, the optical axis of the light irradiated from the lamp unit forward of the vehicle can be adjusted by an aiming operation for adjusting the inclination in the vertical direction and the inclination in the horizontal direction of the lamp unit.

[0026] Further, in the vehicle lamp 1 provided with the optical axis adjustment mechanism 3, after detecting the inclination in the longitudinal direction of the vehicle, the optical axis of the light irradiated from the lamp unit forward of the vehicle is automatically adjusted in the vertical direction by a leveling operation, and it is also possible to correct the fluctuation of the optical axis accompanying the change in the posture of the vehicle.

[0027] Specifically, this optical axis adjustment mechanism 3 includes the leveling actuator 5 of the present embodiment attached to the housing 2 via a bracket 4 as shown in FIG. 2.

[0028] The leveling actuator 5 of the present embodiment has the tip side of the shaft 12 connected to the reflector via a pivot portion 7 provided on one surface of a mount ring 6 located on the back side of the reflector (not shown) constituting the above-described lamp unit.

[0029] In the optical axis adjustment mechanism 3, the mounting ring 6 is supported via the pivot portion 7 so as to be tiltable. Thus, by slidingly driving the shaft 12 of the leveling actuator 5 in the front-rear direction, it is possible to adjust the optical axis of the light irradiated from the lamp unit toward the front of the vehicle while changing the tilt of the reflector connected via the mounting ring 6.

[0030] Note that the optical axis adjustment mechanism 3 is not necessarily limited to the configuration in which the above-described mounting ring 6 is supported via the pivot portion 7 so as to be tiltable. For example, a configuration in which a holder that holds the lamp unit is supported via the pivot portion 7 so as to be tiltable may also be used.

[0031] As shown in FIGS. 3, 4, and 5, the leveling actuator 5 of the present embodiment includes a holder 11, a shaft 12 disposed inside the holder 11, and a rotation motor 13.

[0032] The holder 11 is made of a resin molded body made of synthetic resin. The holder 11 has a front wall 11a, an outer peripheral wall 11b extending rearward from around the front wall 11a, and an opening 11c opened on the back side of the outer peripheral wall 11b, and is formed in a substantially cylindrical shape as a whole.

[0033] The holder 11 has a sleeve portion 14 protruding cylindrically forward from the front side of the front wall 11a, a circular hole portion 15 penetrating the central portion of the sleeve portion 14, a plurality of guide slits 16 axially notching the outer peripheral wall 11b from the rear end side, and a plurality of connecting portions 17 connected between the outer peripheral walls 11b so as to straddle the opening end sides of the respective guide slits 16.

[0034] In this embodiment, four guide slits 16 are provided side by side at equal intervals in the circumferential direction of the outer peripheral wall 11b. That is, these four guide slits 16 are located at four positions, namely, the upper, lower, left, and right of the outer peripheral wall 11b, and are formed by linearly notching with a certain width from the rear end side of the outer peripheral wall 11b. Note that the number of the plurality of guide slits 16 is not limited to the four described above, and may be two or more. When providing three guide slits 16, they may be arranged at three positions on both the left and right sides of the upper and lower sides.

[0035] The connecting portion 17 enhances the mechanical strength of the holder 11 by connecting the space between the outer peripheral walls 11b so as to straddle the opening end side of the guide slit 16.

[0036] In addition, a plurality of claw portions 14a are provided side by side in the circumferential direction on the outer peripheral surface of the sleeve portion 14. Further, a ring-shaped packing P is detachably attached around the sleeve portion 14.

[0037] In the leveling actuator 5 of this embodiment, as shown in FIG. 2, after inserting the sleeve portion 14 from the back side into the mounting hole 4a provided in the bracket 4, by rotating the holder 11 around the central axis of the mounting hole 4a, a plurality of claw portions 14a inserted from a notch portion (not shown) provided around the mounting hole 4a are locked around the mounting hole 4a. As a result, the leveling actuator 5 can be detachably attached around the mounting hole 4a via the packing P.

[0038] As shown in FIGS. 3, 4, and 5, the shaft 12 is made of a resin molded body of synthetic resin having excellent wear resistance and is formed in an overall long axis shape. The shaft 12 has a spherical pivot ball 18 at its tip side, a wheel portion 19 protruding in a circular ring shape from the outer peripheral portion on the rear end side thereof, a plurality of guide protrusions 20 protruding from the outer peripheral portion of the wheel portion 19, and a female screw portion 21 formed along the central axis from the rear end side thereof.

[0039] The shaft 12 protrudes forward from the hole portion 15 of the holder 11 at the tip side, and is slidably supported in the axial direction (front-rear direction) with the wheel portion 19 fitted inside the holder 11.

[0040] In addition, the leveling actuator 5 of the present embodiment includes a guide mechanism that slidably guides a plurality of guide protrusions 20 engaged with a plurality of guide slits 16 in the axial direction. Thereby, the rotation (so-called dragging rotation) of the shaft 12 accompanying the rotation of the rotation shaft 27 of the rotation motor 13 described later is restricted.

[0041] The tip side of the shaft 12 is attached to the mounting ring 6 via the pivot portion 7 described above. The pivot portion 7 connects the tip side of the shaft 12 and the mounting ring 6 by fitting the pivot ball 18 of the shaft 12 into a pivot bearing (not shown) provided on the mounting ring 6.

[0042] The rotation motor 13 is an outer rotor type brushless DC motor. Specifically, this rotation motor 13 has a stator 23 provided with a plurality of coils 22, an outer rotor 25 provided with a plurality of magnets 24, and a motor cover 26 that houses the outer rotor 25 inside between the stator 23.

[0043] In addition, the outer rotor 25 has a rotation shaft 27 protruding forward from the center portion of the front surface thereof and a male screw portion 28 provided on the outer peripheral portion of the rotation shaft 27. The rotation shaft 27 protrudes forward in a state of passing through a center hole 26a provided in the center portion of the front surface of the motor cover 26.

[0044] The rotation motor 13 rotationally drives the rotation shaft 27 by an electromagnetic action acting between the coil 22 on the stator 23 side and the magnet 24 on the outer rotor 25 side.

[0045] The rotary motor 13 is held inside the holder 11 from the back side of the shaft 12 in a state where the male screw portion 28 of the rotary shaft 27 is screwed into the female screw portion 21 of the shaft 12.

[0046] On the surface of the rotary motor 13 facing the wheel portion 19, a plurality of positioning convex portions 29 are provided. In the present embodiment, the plurality of positioning convex portions 29 are provided in three radially arranged around the central hole 26a on the front side of the motor cover 26. Further, the three positioning convex portions 29 are arranged at equal intervals around the central hole 26a, extend linearly in the radial direction of the motor cover 26, and project forward at the same height as each other.

[0047] Note that the positioning convex portion 29 is not necessarily limited to the above-described configuration, and its shape, number, arrangement, etc. can be appropriately changed.

[0048] In the leveling actuator 5 of the present embodiment having the above-described configuration, when the rotary shaft 27 of the rotary motor 13 rotates, the shaft 12 slides in the axial direction due to the screwing of the male screw portion 28 and the female screw portion 21. Further, depending on the rotation direction of the rotary motor 13, the shaft 12 can be advanced or the shaft 12 can be retracted.

[0049] In the leveling actuator 5 of the present embodiment, a brushless DC motor is used for the above-described rotary motor 13, and the axial positioning of the shaft 12 is performed by controlling the rotation of this brushless DC motor.

[0050] That is, in this brushless DC motor, since the rotational position of the outer rotor 25 can always be monitored, it is possible to accurately position the shaft 12 in the axial direction while always monitoring the slid position of the shaft 12 accompanying the rotation of the rotary shaft 27.

[0051] Furthermore, in the leveling actuator 5 of the present embodiment, by using the above-described outer rotor type brushless DC motor, it is possible to obtain the rotational torque of the rotating shaft 27. As a result, a simple structure can be adopted in which the shaft 12 is axially slid by screwing the male screw portion 28 provided on the rotating shaft 27 and the female screw portion 21 provided on the shaft 12, and moreover, a significant reduction in the number of parts and the number of assembly steps is possible.

[0052] Also, in the leveling actuator 5 of the present embodiment, the position where the wheel portion 19 abuts on the above-described positioning convex portion 29 is set as the initial position of the shaft 12. In this case, it is possible to accurately set the initial position of the shaft 12 by the abutment between the positioning convex portion 29 and the wheel portion 19.

[0053] Also, in the leveling actuator 5 of the present embodiment, with the wheel portion 19 fitted inside the above-described holder 11, the plurality of guide protrusions 20 engaged with the plurality of guide slits 16 are slidably guided in the axial direction. As a result, it is possible to accurately slide the shaft 12 within the holder 11 without causing rattling in the shaft 12.

Description of Reference Numerals

[0054] 1... Vehicle lamp 3... Optical axis adjustment mechanism 5... Leveling actuator 11... Holder 12... Shaft 13... Rotating motor 16... Guide slit 17... Connecting portion 19... Wheel portion 20... Guide protrusion 21... Female screw portion 22... Coil 23... Stator 24... Magnet 25... Outer rotor 26... Motor cover 27... Rotating shaft 28... Male screw portion 29... Positioning convex portion

Claims

1. A leveling actuator for adjusting the optical axis of light irradiated from a lamp unit of a vehicle lamp in which the lamp unit is disposed inside a lamp body toward the front of the vehicle, comprising: a shaft slidably supported in the axial direction with the tip side connected to the lamp unit via a pivot portion; a holder that slidably holds the shaft in the axial direction with the tip side of the shaft protruding from a front hole portion; a rotary motor held inside the holder from the back side of the shaft in a state where a male screw portion provided on a rotary shaft is screwed into a female screw portion provided along the central axis of the shaft; the rotary motor being a brushless DC motor; the leveling actuator characterized in that the axial positioning of the shaft is performed by rotation control of the brushless DC motor.

2. The leveling actuator according to claim 1, wherein the brushless DC motor is an outer rotor type.

3. The shaft has a wheel portion protruding in a ring shape from an outer peripheral portion on the rear end side, and a guide protrusion protruding from an outer peripheral portion of the wheel portion; the holder has a guide slit axially notching an outer peripheral portion from the rear end side; the leveling actuator according to claim 1, characterized in that the shaft is axially slid by slidably guiding the guide protrusion engaged with the guide slit in the axial direction with the wheel portion fitted inside the holder.

4. The leveling actuator according to claim 3, wherein the holder has a connecting portion connected between outer peripheral portions so as to straddle an opening end side of the guide slit.

5. The rotary motor has a positioning convex portion on a surface facing the wheel portion; the leveling actuator according to claim 3, characterized in that a position where the wheel portion abuts against the positioning convex portion is set as an initial position of the shaft.

6. A vehicle lamp comprising the leveling actuator according to any one of claims 1 to 5.

Images