JPH0731443Y2 - Lens driving mechanism of variable light distribution type auxiliary headlight - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a lens driving mechanism for a variable light distribution type auxiliary headlight that changes the light distribution of the auxiliary headlight in a plurality of steps by operating a switch. .

[Conventional technology]

Conventionally, as auxiliary headlights for automobiles such as fog lights,
2. Description of the Related Art A variable light distribution type lighting device having a structure in which a distance between two lenses provided on a front optical axis of a projector lamp is expanded / contracted to switch a diffusion angle of irradiation light to control a light distribution pattern is used.

[Problems to be solved by the device]

However, this type of auxiliary headlight lens drive mechanism not only has the problem that the structure becomes complicated and the lamp assembly increases in size, but also the lens stops accurately moving to the set position for mounting on the vehicle. It was difficult to put it into practical use because a robust structure that can be used is required.

The present invention has been made in view of the above problems, and when a driver of a vehicle changes the light distribution of an auxiliary headlight in three steps by a manual switch, the lens is accurately moved to a set position and stopped. It is an object of the present invention to provide a robust and compact lens distribution drive mechanism for a variable light distribution type auxiliary headlamp configured to enable the above.

[Means for Solving the Problems]

In order to achieve the above object, a lens driving mechanism of a variable light distribution type auxiliary headlight according to the present invention provides a drive control device for moving a lens back and forth to a preset position without displacement. (1) In order to move the lens back and forth, a rotary cylinder made of a cylindrical member is provided on the outer circumference of the moving lens, and the outer circumference of the moving lens is rotationally driven only by the cylindrical member driven by a motor. Configure

(2) Two patterns of helicoid-shaped notches or slots are provided on the outer circumference of the rotary cylinder, and a circuit pattern having an insulating portion for defining a stop position is formed corresponding to the helicoid.

(3) Guide pins inserted respectively from above and below the two helicoid guide grooves are directly screwed to the front-rear moving sleeve having the moving lens fixed thereto or the moving lens.

(4) When the outer rotary cylinder rotates, the guide pin moves in the helicoid groove to move the movable lens back and forth, thereby making the relative distance to the fixed lens variable.

At this time, the object can be achieved by constructing the rotation stopping means so that the moving lens does not rotate at the same time.

[Action]

According to the above configuration, the rotating cylinder is driven by the motor in forward and reverse directions and stopped, and the rotating cylinder is provided with a helicoid groove hole for axially displacing the moving lens back and forth, and the motor is driven on the outer periphery of the rotating cylinder. Since the position detecting switch to be controlled is configured, the moving lens can be moved back and forth in the axial direction without rotating, and the moving position of the moving lens is accurate, and is maintained by a robust structure. It is useful as a lamp device.

〔Example〕

Hereinafter, a lens driving mechanism of a variable light distribution type auxiliary headlamp according to the present invention will be described with reference to the drawings.

1 to 6 show a first embodiment of the present invention.

In the drawing, reference numeral 1 is a projector lamp, and a bulb 3 for lighting is provided at a first focal point F1 of an elliptical mirror surface 2a formed by a reflector 2 fixed to a frame 5.
The rear end of the fixed sleeve 7 fastened and integrated to the lens holder 6 fixed to the frame 5 is located on the front optical axis L of the reflector 2 so as to share the focus with the second focus F2 of the elliptical mirror surface 2a. The collimator lens 4 is fixed to the
When the bulb 3 is turned on, the collimator lens 4 constitutes a parallel light source having a light flux parallel to the optical axis L.

Reference numeral 8 is a fixed lens in which a large number of cylindrical lens steps 8a, 8a ...
A movable lens 9 having a large number of cylindrical lens steps 9a, 9a ...
Is fixed to the end of an axial sliding sleeve 10 slidably inserted in the fixed sleeve 7, and both lenses 8,
It is made so that the relative distance between 9 can be changed. The axial sliding sleeve 10 has two guide rollers 12a and 12b rotatably attached to the guide pins 11 and 11 projecting at the upper and lower outer peripheral positions of 180 degrees, and the fixed sleeve 7 One guide roller 1 for each of the axial sliding guide grooves 7a, 7a formed in the axial direction on the cylinder wall.
2b is slidably positioned and is provided in a peripheral wall of a cylindrical rotary cylinder 13 which is rotatably inserted into the fixed sleeve 7.
The guide roller 12a at the end is slidably positioned with respect to the helicoid guide holes 13a, 13a of the strip. The gear 13b formed on the inner periphery of the rear end portion of the rotary cylinder 13 meshes with the gear 15 axially attached to the end portion of the rotary connecting shaft 14 axially provided on the frame 5, and The other end is rotatably connected via a rotation transmission mechanism composed of a gear 17 meshed with a gear 16 axially attached to the other end, a worm wheel 18, and a worm 19 axially attached to the drive shaft of the DC motor 20, and the worm 19 The structure is such that it rotates and shifts to a predetermined angular position by forward and reverse rotation.

Reference numeral 21 is a position detection switch of a rotational position detecting mechanism formed on the outer periphery of the front half of the cylindrical rotary cylinder 13, and the rotary cylinder 13 is made of a conductor such as aluminum. As shown in the exploded view of the part, four sliding brushes 22a, 22b, 22c, 22d each having a base fixed to the frame 5 are slidably contacted with the peripheral surface of the detection part, respectively, and correspond to the helicoid guide groove 13a. At the sliding contact positions of the sliding brushes 22a, 22b, 22c,
Insulators 23a, 23b, 23c such as synthetic resin are embedded so that their peripheral surfaces are flush with each other.

Reference numeral 24 denotes a shade fixedly mounted on the frame 5 so as to be located at the substantially second focal point F2 of the elliptical mirror surface 2a on the front optical axis L of the reflector 2 of the projector lamp 1, and one of the reflected light beams from the reflector 2 The part is cut and the light distribution pattern is adjusted.

The lens driving mechanism of the variable light distribution type auxiliary headlamp having the above-described configuration drives the motor 20 in the forward and reverse directions through a drive control circuit described later to obtain a predetermined light distribution pattern.

That is, when the motor 20 is driven to rotate, the rotary connecting shaft 14 rotates via the worm 19, the worm wheel 18, and the gears 17 and 16, and the gear 15 and the gear 15 attached to the end of the rotary connecting shaft 14 are rotated. 13b
The rotary cylinder 13 that meshes with is rotationally displaced in the forward or reverse direction about the fixed sleeve 7 as an axis. Due to this rotational displacement, the rotary cylinder
The guide roller 12b engaged with the helicoid guide groove 13a of the guide sleeve 13a and the guide roller 12a engaged with the axial sliding guide groove 7a of the fixed sleeve 7 so as to restrict the displacement in the rotational direction, and the guide pin. Since 11 is coaxial, the axial sliding sleeve 10 projecting the guide pin 11 is axially displaced along the inner wall of the fixed sleeve 7 according to the axial displacement of the helicoid guide groove. Therefore, the movable lens 9 fixed to the axial sliding sleeve 10 is displaced back and forth on the optical axis L to change the relative distance to the fixed lens 8, and the lens step 8a of both lenses 8 and 9 is changed. The transmitted light beam is converged or diffused depending on the distance of 9a.

The amount of displacement of the axial sliding sleeve 10 can be detected by a position signal from a position detection switch 21 formed on the outer periphery of the front half of the rotary cylinder 13. That is, since the rotary cylinder 13 is made of a conductor, the sliding brush 22d for grounding is used.
And insulators 23a, 2 between the other three sliding brushes 22a, 22b, 22c.
Except for the portions 3b and 23c, they are electrically connected. Therefore, the positions of the insulators 23a, 23b, and 23c should be changed to the helicoid guide holes 1
By configuring corresponding to the positions corresponding to the three step portions a, b, and c of 3a, each position can be detected and accurately controlled by the control drive circuit.

Next, an embodiment of the control drive circuit will be described with reference to FIG.

The control drive circuit activates the sensor input section 30 in response to the switch signal from the position detection switch 21, and outputs the full C-MOS.
The IC and the motor drive unit 35 are large capacity transistor BTs.
It is configured so that the motor can directly rotate in the reverse direction by the L connection.

The control drive circuit is roughly divided into a sensor input unit 30, a switch input unit 31, a reset circuit 32, a data holding unit 33, a data comparison unit 34, a motor drive unit 35, and a power supply unit 36.

The sensor input unit 30 is the same as the position detecting switch 21 of the above-mentioned configuration.
It is connected to the individual sliding brushes 22a, 22b, 22c, 22d, and the chattering phenomenon caused by the frictional movement of the sliding brushes 22a, 22b, 22c, 22d is received by the integrating circuit and the photocoupler to prevent the adverse effect. The signal input from the position detection switch 21 turns on the internal LED of the photocoupler when the selected position is low level, and the internal phototransistor turns off.
It becomes N, and the output is transmitted as a low level, but the logic is inverted by the inverter immediately after that and the switch information becomes a high level.

The switch input section 31 is a rotary switch for selecting
Since SW1 is used, there is a lot of chattering in the structure of the switch (a phenomenon in which ON / OFF is repeated because the contacts rub and move repeatedly), and it is received by the same integrating circuit and photo coupler as the sensor input section 30. It prevents the adverse effects.
The input signal turns on the LED inside the photocoupler because the selected place is low level, the internal phototransistor turns on, and the output is transmitted as low level, but immediately after that The inverter inverts the logic and the switch information becomes high level.

In the subsequent stage of the sensor input unit 30, a data holding unit 33 that holds a sensor signal so that the sensor can be changed later is provided. The holding circuit is a C-MOS IC (RS flip-flop). The reset circuit 32 resets the flip-flops other than the switches input from the sensor input unit 30. Moreover, all the flip-flops are reset when the power is turned on.

A data comparison unit 34 is formed in the subsequent stage of the switch input unit 31 and the data holding unit 33. Here, the switch input section
The switch data from 31 and the sensor data from the data holding unit 33 are compared (calculated), the magnitude of the result is judged and the next motor drive unit 35 is moved to move the moving lens 9 forward or backward. Output a signal. At this time, if the calculation results are equal, the operation is stopped.

The motor drive unit 35 at the next stage is a circuit that directly drives the DC motor 20, and forms a bridge circuit with four large-capacity transistors, and forms a circuit that reverses the direction of the current flowing through the motor 20.

Further, the power supply circuit 36 creates a 5V power supply P5 for driving the motor and a 5V power supply P5M for driving the control circuit.

Next, FIGS. 8 to 13 show another embodiment of the present invention.

Explaining only the parts different in configuration from the first embodiment, the fixed lens 8 and the moving lens 9 have a rectangular outer shape, and the same lens steps 8a and 9a as those in the first embodiment are provided.
Is configured. Fixed lens frame 40 fixed to frame 5
Includes a pair of slide shafts installed in parallel with the optical axis L.
An annular member 42 in which the collimator lens 4 is fixed to the axis is fixed via 41, 41, and a helicoid guide hole 43a is formed in the outer end portion of the annular member 42 and the fixed lens frame 40. A cylindrical rotary cylinder 44 made of an insulating material such as resin is rotatably mounted on an outer shaft. Reference numeral 45 denotes a front and rear sliding sleeve on which the movable lens 9 is fixedly mounted, and sliding holes 45a, 45a pre-installed at a 180-degree position are externally slid on the slide shafts 41, 41. At the same time, a helicoid drive pin 46 protruding from the outer peripheral surface of the front-rear sliding sleeve 45 is slidably inserted into the helicoid guide hole 43a. Further, a helicoid drive gear 47 is fixedly provided at the end of the rotary cylinder 44, and is rotatably connected to the DC motor 20 through an appropriate rotation transmission mechanism as in the first embodiment. The rotary cylinder 44 is configured to rotate by the forward and reverse rotation of the motor 20. On the outer circumference of the rotary cylinder 44, there are four contact points 48a around the strip conductor,
48b, 48c and 48d are formed, and the contact points of 48a, 48b and 48c are formed with gaps a, b and c at positions corresponding to the helicoid guide holes 43a as shown in FIG. The position detection switch 48 is in contact with the fixed sliding brushes 49a, 49b, 49c, 49d.

In addition, 50 is an optical axis L in front of the bulb 3 of the projector lamp 1.
It is an interlocking type shade provided above, is attached to the frame 5 via a link mechanism 51, is pivotally installed so as to be able to move in and out in a direction crossing the optical axis L, and the swing arm 52 end of the link mechanism 51 is provided. And the one end of the front-rear sliding sleeve 45 is connected via a connecting rod 53.

The lens driving mechanism of the variable light distribution type auxiliary headlamp having the above configuration is
The motor 20 is driven in forward / reverse rotation or stopped by an input signal from the position detection switch 48.

[Effect of device]

Since the lens driving mechanism of the variable light distribution type auxiliary headlight according to the present invention is configured as described above, the moving lens is moved relative to the fixed lens along the helicoid guide hole, and
As shown in FIG. 14, the light distribution pattern is switched, and the position detecting means for controlling and driving the motor is formed on the outer circumference of the rotary cylinder having the helicoid guide hole. Has a characteristic that is maintained by an accurate and robust structure, and the practical effect after implementing the present invention is extremely large.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a first embodiment of a lens driving mechanism of a variable light distribution type auxiliary headlight according to the present invention, FIG. 2 is the same plane sectional view, and FIG. 3 is the right side in FIG. Fig. 4, Fig. 4 is a left side view of the same, Fig. 5 is an exploded view of a main part showing a helicoid portion, Fig. 6 is an exploded perspective view, and Fig. 7 is a circuit diagram showing an embodiment of a drive control circuit of the device. FIG. 8 is a side sectional view showing another embodiment of the present invention, FIG. 9 is a sectional plan view of the same, FIG. 10 is a right side view of FIG. 8, FIG. 11 is a left side view of the same, and FIG. Is an exploded view of a main part showing a helicoid part, FIG. 13 is an exploded perspective view, and FIG. 14 is an explanatory view showing switching of a light distribution pattern by the device of the present invention. 1 ... Projector lamp 2 ... Reflector, 3 ... Lighting bulb 4 ... Collimator lens, 5 ... Frame 7 ... Fixed sleeve, 8 ... Fixed lens 9 ... Moving lens 10 ... Axial sliding sleeve 11 ...... Guide pin, 13,44 …… Rotating cylinder 13a, 43a …… Helicoid guide hole 13b …… Gear, 20 …… Motor 21 …… Position detection switch 22a, 22b, 22c, 22d …… Sliding brush 23a, 23b , 23c, 23d …… Insulator 24 …… Shade, 40 …… Fixed lens frame 41 …… Slide shaft 42 …… Ring member, 45 …… Front and rear sliding sleeve 46 …… Helicoid drive pin 48 …… Position detection switch 48a , 48b, 48c, 48d …… Contact 49a, 49b, 49c, 49d …… Sliding brush 50 …… Interlocking shade

Claims (3)

[Scope of utility model registration request] 1. A variable light distribution for arranging a fixed lens and a moving lens on the front optical axis of a parallel light flux irradiating means such as a projector lamp, and moving the moving lens in the optical axis direction to condense and diffuse the light flux. Type auxiliary headlamp, the lens driving mechanism of the variable light distribution type auxiliary headlamp is rotatably provided on the outer periphery of the movable lens, and is driven forward / reversely by driving a motor through an appropriate rotation transmission mechanism. And a guide pattern consisting of a helicoid cutout or a slot in the rotary cylinder, and a circuit pattern having an insulating part or a non-conductive part for defining a stop position. Position detecting means formed corresponding to the helicoid, and inserted from the helicoid-shaped guide pattern,
A front-rear moving sleeve having the movable lens fixed thereto or a guide pin directly protruding from the movable lens; and a detent slide means for blocking the rotation of the movable lens and pivotally mounted so as to be slidable in the optical axis direction. A lens driving mechanism for a variable light distribution type auxiliary headlight. 2. A rotation stopping means is provided with a cylindrical fixed sleeve between a cylindrical front and rear sliding sleeve for fixing a moving lens and the rotary cylinder externally inserted on the front and rear sliding sleeve, and the fixed sleeve has a shaft. The lens driving mechanism of the variable light distribution type auxiliary headlamp according to claim 1, wherein the lens driving mechanism has a structure in which a direction movement guide groove is provided. 3. The variable light distribution according to claim 1, wherein the detent means has a structure in which two slide shafts fixed to separate members are slidably inserted into the movable lens. Lens drive mechanism for type auxiliary headlight.