JPH056346U - Angle sensor for optical axis adjustment - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a device capable of detecting the tilt angle of a vehicle body regardless of the inclination of the road surface in order to enable automatic adjustment of the headlight optical axis direction due to the tilt of the vehicle body. The purpose is to [Structure] Fixed to the vehicle body, with respect to the base 6,
The case 8 is rotatably supported by the case shaft 7, and the light shielding plate 3 is suspended in a pendulum shape by the horizontal shaft 2 with respect to the case 8. The relative angle between the light shielding plate 3 and the case 8 is detected by a photoelectric sensor (not shown).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sensor for measuring an angle of an optical axis of a headlight mounted on an automobile in order to adjust the optical axis of the headlight.

[0002]

[Prior Art]

 Headlights for automobiles are dangerous because they dazzle oncoming vehicles if they are facing upwards too much. On the other hand, if it is facing down too much, the road ahead in the direction of travel will not be illuminated well and it will be difficult to drive. Therefore, it is necessary to provide a vehicle headlamp with a device for adjusting the optical axis of the vehicle headlamp slightly upward and downward with the headlamp mounted on the vehicle body. A headlamp generally has a structure in which a concave reflecting mirror is provided in the lamp housing and a light source bulb is located near the focal point of the concave reflecting mirror. The optical axis of the headlamp is the symmetry axis of the concave reflecting mirror. It means Therefore, in order to adjust the optical axis, (a) tilt the lamp housing up and down while keeping the relative position of the lamp housing and the concave reflecting mirror constant, or (b) mount the lamp housing on the vehicle body. There are two methods, one is to tilt the concave reflecting mirror up and down without moving it with the attached shade. In any of the above methods, when an automobile is manufactured in a specialized factory, the optical axis is precisely adjusted (aiming) using a dedicated measuring instrument in the final adjustment immediately before shipment, and further inspection is performed. However, even if the optical axis direction of the headlight is adjusted accurately in the standard condition of the vehicle, the flexing state of the suspension spring of the vehicle body changes when the state of the load or passengers changes, and the levelness of the vehicle body changes. Change. The optical axis of the headlight is adjusted (aiming) on the assumption that the vehicle body is horizontal, so when the vehicle body leans forward and upward, the optical axis goes upward, and when the vehicle body leans forward and downward, The axis will face downwards. Therefore, it is necessary to temporarily adjust (level) the optical axis direction of the headlight according to such changes in the usage conditions. As mentioned above, there is also proposed a technology for performing the optical axis adjustment (leveling) according to the situation by remote control from the driver's seat.

[0003]

[Problems to be solved by the device]

In the conventional technology, the prompt optical axis adjustment is performed by operating the switch in the driver's seat to rotate the leveling motor forward and backward. This operation puts a burden on the driver, so automatic adjustment is desirable if possible. The present inventor has conducted research and development on an automatic leveling device from such a viewpoint, but a sensor for detecting an inclination angle of an automobile body is required to perform the automatic leveling. FIG. 8 is a schematic cross-sectional view showing an angle detection sensor (hereinafter referred to as a trial angle sensor) created by the present inventor for an automatic leveling device for a headlight, which is drawn by cutting the case 1. .. A light shield plate 3 is rotatably suspended in a case 1 by a horizontal shaft 2. The AA cross section is shown in FIG. The light shielding plate 3 is provided with slits 4a, 4b, 4b ', 4c, 4c' radially around a fulcrum of the horizontal axis 2. Emitters / receivers 5a, 5b, 5b'5c, 5c 'are provided corresponding to the slits. FIG. 5 shows only 5a of these light emitters / receivers. A pair of emitter and receiver 5a is a photoelectric switch mechanism opposition to the light emitting element 5 a ₁ and a light receiving element 5a _2. In the present invention, a photoelectric switch is a light source that converts and radiates an electric quantity into a light quantity, and the radiated light is blocked by, or reflected, absorbed, and transmitted by, an object to be detected. A light receiving element receives the changed light, photoelectrically converts it, adds some amplification and control to the amount of change, and obtains an ON-OFF switching output as the final control output. There is a slight difference between the arrangement pitch of the slits 4a to 4c 'and the arrangement pitch of the light emitters / receivers 5a to 5c'. Thereby, the tilting of the case 1 at a small angle can be detected. In this angle sensor (FIGS. 8 and 9), the center line ZZ of the case 1 is vertical to the chassis surface of the automobile, and the horizontal axis 2 is a horizontal direction perpendicular to the longitudinal center line of the automobile. Is installed in. The present inventor developed an automatic leveling (immediate response optical axis adjustment) device for a vehicle headlight using the above angle sensor (Figs. 4 and 5), and succeeded in a static test. However, there are still the following problems regarding practicality in a dynamic state (running state of an automobile). When the case 1 is fixed to the vehicle body of the automobile and installed so that the central axis Z of the case 1 is perpendicular to the chassis, the center of gravity G of the light shielding plate 3 and the horizontal axis 2 are connected. When the slit 4a on the line coincides with the central axis Z of the case 1, it is determined that the chassis is horizontal. The fact that the chassis is horizontal means that the load is in good condition, and the optical axis of the headlamp that is fixed relative to the chassis is in the correct direction. However, the above judgment is based on the assumption that the vehicle is placed on a level ground. For example, when a car is on a sloping road, the chassis is tilted even if the load is not even and uneven. Therefore, even if the chassis is tilted with respect to the earth, it cannot be said that the cargo is biased. The present invention has been made in view of the above circumstances, and provides an optical axis adjustment angle sensor capable of determining whether or not a load is unbalanced regardless of the inclination of the road surface on which the vehicle is placed. The purpose is to provide.

[0004]

[Means for Solving the Problems]

 As a configuration for achieving the above object, an angle sensor for adjusting an optical axis of a vehicle headlamp according to the present invention comprises a light shield plate suspended in a pendulum shape, and a slit provided on the light shield plate. An angle sensor for adjusting the optical axis, comprising an optoelectronic switch mechanism composed of a light projecting section and a light receiving section, which are installed so as to face each other via the light shielding plate, and rotate with respect to the vehicle body of an automobile. There is provided a case that is movably supported and provided with means for adjusting the rotation angle. The light shielding plate is pendulum-like suspended by a horizontal shaft with respect to the case, and The switch is characterized by being installed in the above case.

[0005]

[Action]

 The case of the angle sensor configured as described above can be rotationally adjusted with respect to the vehicle body.

When the center axis of the case is set to be perpendicular to the chassis and the load is not biased, the declination of the pendulum light-shielding plate with respect to the case indicates the slope of the ground. .. Therefore, if the rotation angle of the case is adjusted so as to correct the gradient, it is possible to detect the presence or absence of the deviation of the load on the ground by the deviation angle of the light shielding plate. In the present invention, it is considered that the optical axis of the headlight is oriented in the correct direction if there is no bias in the load of the automobile (or the load of passengers).

[0007]

【Example】

 FIG. 1 is a perspective view schematically showing an embodiment of the present invention. A base member 6 is fixed to the body of the automobile. A case 8 is rotatably supported on the base 6 by a case shaft 7. The case axis is set in a horizontal direction that is perpendicular to the center line of the vehicle in the traveling direction. A light blocking plate 3 is suspended like a pendulum by a horizontal shaft 2 that is parallel to the case shaft 7. Although not shown, the above-mentioned light-shielding plate 3 is provided with the slit described with reference to FIG. 8, and the light emitter / receiver is arranged so as to face each other through the slit and is fixed to the case 8. .. Thereby, the rotation angle position of the light shielding plate 3 with respect to the case 8 in the arrow de direction can be measured. Gear teeth 9 centering on the case shaft 7 are provided at the lower end of the case 8 and mesh with the intermediate gear 10. The intermediate gear 10 meshes with a source gear 11 and is rotationally driven by a motor 12. With the configuration described above with reference to FIG. 1, the rotation angle position of the case 8 can be controlled by operating the motor 12, and the earth can be moved regardless of the posture of the automobile body to which the base 6 is fixed. As a reference, the rotation angle position of the case 8 can be detected. FIG. 2 is an explanatory diagram when an automobile on a horizontal road surface is in an empty state. In the figure, (21) is a road surface and 22 is a freight vehicle. The headlight of this car is correctly fixed to the car body, and the optical axis of the headlight is at a regular angle when there is no load. In the present invention, the empty load means a state in which the luggage is not placed on the bed, the fuel is filled in the fuel tank, and the occupant is seated on the seat. When the empty vehicle is on a horizontal road surface as shown in Fig. (A), its bed is horizontal, and when the case 8 is in the neutral position as shown in Fig. (B), its center line. Z has a vertical posture. However, the neutral position of the case 8 means a position parallel to the center line of the base 6. In this state, the shading plate 3 is suspended right below the horizontal axis 2 and its center line coincides with the Z axis. Therefore, the photoelectric switch (not shown in FIGS. 2 to 7) installed in the case 8 outputs a signal indicating that the posture of the light shielding plate has no deviation. As shown in FIG. 3 (A), when a cargo 23 is mounted on a freight vehicle 22 on a horizontal road surface 21 and the vehicle body leans forward by an angle a °, the base fixed to the vehicle body. 6 and the case 8 fixedly supported with respect to the base 6 are inclined by an angle a ° with respect to the vertical line V with respect to the earth. In this state, the shading plate 3 is suspended right below the horizontal axis 2 and its center line coincides with the vertical line V 1. In this way, the centerline Z of the case 8 forms an angle of a ° with respect to the vertical line V of the earth, and the photoelectric switch (not shown) provided in the case 8 has an angle of a °. To detect. The inclination angle (a) of the vehicle body caused by the deviation of the load 23 on the horizontal road surface 21 is detected as described above. Therefore, the detected angle (a) is input to a computer (not shown) and attached to the headlight. The optical axis can be adjusted by operating an automatic leveling device (both not shown) provided. In this case, the direction of the optical axis of the headlight is misaligned due to the tilt of the vehicle body. Therefore, keeping the tilt of the vehicle body unchanged and changing the optical axis direction of the headlight installed on the vehicle body, the correct direction is obtained. The idea is to Further, when it is considered that the deviation of the load is eliminated and the traveling safety is aimed at, it is possible to correct the load state so that the inclination angle (a) becomes zero. The explanation of FIGS. 2 and 3 is about the optical axis adjustment relating to the vehicle body inclination due to the inclination of the load on the horizontal road surface 21. Next, referring to FIGS. 4 and 5, the optical axis adjustment on the ascending road surface will be described. The adjustment will be described. FIG. 4 (A) shows a state in which the freight vehicle 22 is stopped on an ascending road surface 24 at an angle θ with no cargo. At this time, as shown in FIG. 7B, the vertical line V is inclined by an angle θ with respect to the center line Z of the case 8, and this angle θ is detected by the photoelectric switch installed in the case 8. Therefore, the motor 12 shown in FIG. 1 is operated to rotate the case 8 in the direction of the arc arrow f-g, and the center line Z of the case 8 is aligned with the vertical line V as shown in FIG. 4C. The preparation is made as described above, but this preparation is performed by a computer (not shown). If the vehicle body is tilted by an angle b ° in this state as shown in FIG. 5 (A), the center line Z and the vertical line V, which are aligned in FIG. 4 (C), are shown in FIG. 5 (B). Open only at angle b °. Since this angle b ° is detected by the photoelectric switch installed in the case 8, the automatic leveling device of the headlight can be operated based on this detection signal. 6 and 7 are explanatory views of the action and effect on the descending road surface 25. As shown in FIG. 6 (A), when an empty cargo vehicle 22 is parked on the descending road surface 25 with the angle φ and the case 8 is in the neutral position, the case 8 is moved to the case 8 as shown in FIG. 6 (B). The center line Z of the angle V forms an angle φ with the vertical line V. As shown in FIG. 6C, the case 8 is rotated so that its center line Z is aligned with the vertical line V. After preparing as described above, if the vehicle is loaded on the freight vehicle 22 as shown in FIG. 7 (A) and the vehicle body is tilted forward by an angle b °, the inside of the case 8 is as shown in FIG. 7 (B). The core line Z opens at an angle b ° with respect to the vertical line V. This angle b ° is detected by a photoelectric switch (not shown) installed in the case 8. The optical axis is automatically corrected when the automatic leveling device for the headlight (not shown) is operated based on the detected value (angle b °).

[0008]

[Effect of the device]

 As described above, a pendulum-shaped light-shielding plate, a slit provided on the light-shielding plate, and a photoelectric switch mechanism including a light-projecting unit and a light-receiving unit that are installed to face each other through the light-shielding plate. An angle sensor for adjusting an optical axis, which is rotatably supported with respect to a vehicle body of an automobile, and is provided with a case having means for adjusting a rotation angle. According to the structure in which the light shielding plate is suspended in a pendulum shape by a horizontal axis with respect to the case, and the photoelectric switch is installed in the case, the slope of the road surface on which the vehicle is placed is inclined. Regardless of the situation, it has the excellent practical effect of being able to automatically detect the tilt of the automobile body due to uneven load, and contributes to the automation of the prompt adjustment of the optical axis of the headlight (leveling). However, it is huge.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of the present invention.

FIG. 2 is an explanatory view of a preparation operation on a horizontal road surface.

FIG. 3 is an explanatory view of a tilt angle detecting function of an automobile body on a horizontal road surface.

FIG. 4 is an explanatory diagram of a preparatory operation on a climbing road surface.

FIG. 5 is an explanatory view of a tilt angle detection function of an automobile body on a climbing road surface.

FIG. 6 is an explanatory diagram of a preparatory operation on the descending road surface.

FIG. 7 is an explanatory view of a tilt angle detecting action of the vehicle body on the descending road surface.

FIG. 8 is a partial sectional front view of the angle sensor.

9 is a cross-sectional view taken along the line AA shown in FIG.

[Explanation of symbols]

1 ... Case, 2 ... Horizontal axis, 3 ... Shading plate, 6 ... Base, 7
... case axis, 8 ... case, 21 ... horizontal road surface, 22 ... lorry, 23 ... cargo, 24 ... climbing slope, 25 ... descending road surface.

Claims (1)

[Claims for utility model registration] [Claim 1] A light-shielding plate suspended in a pendulum shape, a slit provided in the light-shielding plate, and a light-projecting unit and a light-receiving unit that are opposed to each other through the light-shielding plate. An optical axis adjustment angle sensor comprising a photoelectric switch mechanism consisting of, and a case that is rotatably supported with respect to the vehicle body of an automobile and that includes means for adjusting the rotation angle. Is provided,
The optical axis adjusting angle sensor, wherein the light shielding plate is suspended in a pendulum shape by a horizontal axis with respect to the case, and the photoelectric switch is installed in the case.