JPS6363063B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for measuring the cut line of a passing beam projected from a headlamp of an automobile, and more particularly to a headlamp that can be switched between a running beam and a passing beam. The present invention relates to a device for measuring the position of the cut line when the headlamp is set to a low beam, in a type of headlamp which has a cut line at least when the headlamp is set to a low beam.

As a safety standard for road transport vehicles, the downward angle of the running beam projected from the headlights of an automobile is regulated. Recently, halogen lamps, which have excellent performance in terms of durability and brightness, have been widely used as light bulbs for headlamps. Furthermore, various countries around the world have various regulations regarding the safety standards for the running beams and passing beams projected from headlamps, and these safety standards have changed in various ways due to the development of industry and trade.

The present invention has been developed in view of the above circumstances, and is capable of coping with the diversification of headlamps and standards for running beams and passing beams, and is capable of accurately measuring the cut line position or angle of the beam projected from the headlamp. The purpose is to provide a device for That is, the headlamps of automobiles can normally be switched between a running beam that can illuminate a relatively long distance and a passing beam that can illuminate a relatively short distance, which is used when there is an oncoming vehicle. In this case, although not limited to halogen lamps, headlamps that are configured to irradiate light only to one side of a certain limit line when using a passing beam have come to be widely used. Such a critical line is usually called a cut line, and it is important to ensure that this cut line has a predetermined position or downward angle so as not to dazzle the driver of an oncoming vehicle when used as a passing beam. For this reason, in the past, the pattern irradiated onto a flat plate was judged visually, but the present invention has been made by focusing on this point.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. As shown in FIG. 1, the apparatus of this embodiment roughly consists of a dark box 1, a condensing lens 2, a mirror 3, a universal joint 4, a screen 5, and a photocurrent difference meter 6.
a, 6b and 6c, frequency meters 7a and 7b, and a transmission section 8. car head lamp 9
A dark box 1 is disposed facing the front. dark box 1
A condenser lens 2 is mounted on the surface facing the head lamp 9.
is installed. The inside of the dark box 1 is hollow, and has a structure in which no external light is allowed to enter, except for the condensed beam passing through the condensing lens 2. The condensing lens 2 has a function of condensing the light emitted from the headlamp 9, and it is desirable that the diameter of the condensing lens 2 is at least larger than the external dimension of the headlamp 9 in the vertical direction. Further, the structure of the condenser lens 2 and the arrangement of the dark box 1 are such that the upper and lower ends of the headlamp 9 are located within the height range of the upper and lower ends of the condenser lens 2. A screen 5 is provided above the condensing lens 2 of the dark box 1. A mirror 3 is arranged so as to reflect the beam passing through the condensing lens 2 and condense it onto a screen 5. Note that it is desirable that the optical path distance from the condenser lens 2 to the screen 5 be the same as the focal length of the condenser lens 2. The mirror 3 is connected to a universal joint 4 and can be tilted vertically and horizontally, and the center of rotation of the mirror 3 is located on the center line 10 of the condenser lens 2.
This universal joint 4 rotates the respective dials of angle meters (dials) 7a and 7b attached to the outside of the dark box 1, thereby controlling the mirror 3 via a transmission section 8 consisting of gears, chains, etc. It has the function of rotating vertically and horizontally. Alternatively, the beam from the condenser lens 2 may be directly incident on the screen 5 disposed on the center line 10 of the condenser lens 2 without providing a mirror or the like in the optical path. In this case, the dimensions of the dark box 1 in the direction of the optical axis 10 and the arrangement position of the screen 5 are preferably determined in consideration of the focal length of the condenser lens 2. Further, in this case, it is preferable that the screen 5 be moved vertically and horizontally by rotating the dials of the angle meters 7a and 7b through a transmission section.

In this way, when lens 2 is used, it is possible to place the device close to the headlamp and perform measurements, and by using dark box 1, it is possible to perform measurements without being affected by external light. It is possible to carry out measurements.

On this screen 5, as shown in FIG.
A reference vertical line 11 is provided in the vertical direction, and a reference horizontal line 12 is provided perpendicular to this reference vertical line. Further, a reference cut line 13 may be provided downward from the reference horizontal line 12 at a position corresponding to a reference downward angle of a passing beam determined by safety standards. A photoelectric sensor G is provided at the intersection of the reference vertical line 11 and the reference horizontal line 12 in order to measure the photoelectricity of the beam emitted from the headlamp 9. On the reference horizontal line 12, photoelectric sensors C and D of the same performance are placed at equal distances on both sides of the photoelectric sensor G.
is installed. Similarly, photoelectric sensors E and F having the same performance are arranged on the reference vertical line 11 at positions equidistant above and below the photoelectric sensor G. On the right side of the photoelectric sensor D arranged on the reference horizontal line 12,
A pair of photoelectric sensors A and B having the same performance are disposed one above the other and facing each other with the reference horizontal line 12 in between. In this case, it is desirable that the light-receiving surfaces of the photoelectric sensors A and B are arranged as close to the reference horizontal line 12 as possible, and further, the light-receiving surfaces of the photoelectric sensors A and B are extended along the reference horizontal line 12. It is good if it has a suitable shape. Also, the photoelectric sensors A and B are connected to the reference horizontal line 12.
A plurality of pairs of photoelectric sensors A and B may be arranged along the reference cut line 13, and photoelectric sensors A and B may be arranged facing each other on both sides of the reference cut line 13.

It is preferable to use photovoltaic elements or photoconductive elements as these photoelectric sensors. An example of using a photovoltaic element as a photoelectric sensor will be described below. As shown in FIG. 3, the wiring of the photoelectric sensors A and B connects one electrode of the photoelectric sensor A and the electrode of the photoelectric sensor B, which has the same polarity as that electrode. The other electrode of the photoelectric sensor A and the electrode of the photoelectric sensor B having the same polarity as the other electrode are respectively connected to a photocurrent difference meter 6c. In FIG. 3, the cathodes of photovoltaic elements A and B are connected to each other, and the anodes of each are connected to a photocurrent difference meter 6c. If a photoconductive element is used, the connection may be made in the same manner. When two photovoltaic elements and a photocurrent difference meter are connected in this way and a beam is incident on the two photovoltaic elements, currents in opposite directions are generated in this closed circuit 14 depending on the amount of incident light. The current difference is measured by the photocurrent difference meter 6.
It is displayed in c. Note that the photocurrent difference meter 6c is attached to the outside of the dark box 1. In addition, when multiple pairs of photoelectric sensors are arranged along the reference horizontal axis, a pair of photovoltaic elements with electrodes of the same polarity connected as described above are connected in parallel as shown in Fig. 4. That's good. When a set of photovoltaic elements are connected in parallel in this way, more accurate measurement is possible than when a single set of photovoltaic elements is used, and the current generated in a closed circuit is will also become larger. As described above, when one electrode of one photoelectric sensor is connected to the electrode of the other photoelectric sensor that has the same polarity as that electrode, and the other two electrodes are connected to a photocurrent difference meter. In this case, there is no need to separately provide a predetermined element or circuit to take the difference between the photocurrents output from the two photoelectric sensors, amplify the difference, and input the difference into the photocurrent difference meter.

The photoelectric sensors C and D are connected to an amplifier 15a, as shown in FIG. 5, and the amplifier 15a is connected to a photocurrent difference meter 6a. When the photocurrents output from the photoelectric sensors C and D are input to the amplifier 15a, the difference between the two photocurrents is amplified and the photocurrent difference is displayed on the photocurrent difference meter 6a.
Similarly, photoelectric sensors E and F are connected to an amplifier 15b, and the amplifier 15b is connected to a photocurrent difference meter 6b. When the photocurrents output from the photoelectric sensors E and F are input to the amplifier 15b, the difference between the two photocurrents is amplified, and the photocurrent difference is displayed on the photocurrent difference meter 6b. Further, as in the case of photoelectric sensors A and B, photoelectric sensors C and D and photoelectric sensors E and F may be connected as shown in FIG.

Next, the operation of the apparatus of this embodiment will be explained.
After stopping the car at a predetermined position in front of dark box 1,
As shown in FIG. 1, the height of the dark box 1 is adjusted so that the top and bottom ends of the automobile headlamp 9 are within the height range of the top and bottom ends of the condenser lens 2 attached to the dark box 1. do.

Next, the headlamp 9 is turned on to project a traveling beam 16 as shown in FIG. The traveling beam 16 shown in FIG. 6 is represented by an isolux curve. Traveling beam 1 projected from headlamp 9
As shown in FIG. 1, the beam 6 enters the condensing lens 2 and is converted into a focused beam by the condensing lens 2. The beam travels straight through the dark box 1, is reflected by the mirror 3, and illuminates the screen 5. For this reason, photoelectric sensors C, D, E, F, G provided on the screen 5
The traveling beam 16 is incident on. It is possible to measure the luminous intensity of the traveling beam by the photocurrent output from the photoelectric sensor G. Then, the photocurrent from the photoelectric sensors C and D is transmitted to the amplifier 1 as shown in FIG.
In the amplifier 15a, the difference between the two photocurrents is amplified and outputted to the photocurrent difference meter 6a.

Next, the inspector manually moves the angle meter 7 while visually observing the photocurrent difference displayed on the photocurrent difference meter 6a.
Rotate the dial a so that the photocurrent difference becomes zero. Therefore, as the dial of the angle meter 7a rotates, the mirror 3 is rotated in the left-right direction by the universal joint 4 via the transmission part 8, and the traveling beam 16 is moved in the left-right direction along the reference horizontal line 12 of the screen 5. , when the vertical optical axis 18 of the running beam 16 and the reference vertical line 11 of the screen 5 coincide, the running beam 16
The horizontal center of the reference horizontal line 12 coincides with the horizontal center of the reference horizontal line 12.

Photocurrents from the photoelectric sensors E and F are output to the amplifier 15b as shown in FIG.
In this case, the difference between the two photocurrents is amplified and output to the photocurrent difference meter 6b. The inspector uses a photocurrent difference meter 6
While visually observing the photocurrent difference displayed in b, manually turn the dial of the angle meter 7b so that the photocurrent difference becomes zero. Therefore, by rotating the dial of the angle meter 7b, the mirror 3 is rotated vertically, and the traveling beam 16 is moved vertically along the reference vertical line 11 of the screen 5, and the traveling beam 16 is moved vertically along the reference vertical line 11 of the screen 5.
6 horizontal optical axis 17 and the reference horizontal line 1 of the screen 5
2 coincide with each other, the vertical center of the traveling beam 16 and the vertical center of the reference vertical line 11 coincide, and the alignment of the traveling beam 16 and the screen 5 is completed. The completion of this alignment means that the measurement of the optical axis center position of the traveling beam is completed, and the optical axis center is indicated by the angle meter dials 7a and 7b.

Next, the headlamp 9 is switched from the running beam to a passing beam 19 as shown in FIG. The passing beams shown in FIG. 7 are represented by isolux curves. A passing beam 19 projected from the headlamp 9 travels in the same manner as the traveling beam 16 and illuminates the screen 5. For this reason, the seventh
The reference horizontal line 1 of the screen 5 at the upper end line of the passing beam 19, ie, the cut line 20, as shown in the figure.
A passing beam 19 is incident on the photoelectric sensors A and B depending on the position relative to the photoelectric sensor 2.

Next, the inspector rotates the dial of the angle meter 7b to connect the mirror 3 via the transmission part 8 and the universal joint 4.
is rotated in the vertical direction to move the passing beam 19 upward or downward along the reference vertical line 11 of the screen 5.

For this reason, since the photoelectric sensors A and B are connected as shown in FIG. 3 to form a closed circuit 14, the vertical movement of the passing beam 19 causes, for example,
When a passing beam 19 is incident on the photoelectric sensor B and almost none is incident on the photoelectric sensor A, the photocurrent generated from the photoelectric sensor B in the closed circuit 14 in the direction of the arrow 21 and from the photoelectric sensor A in the direction of the arrow 21' is larger. A photocurrent is generated, and the difference in photocurrent between the photoelectric sensors A and B becomes maximum, and the pointer 22 exhibits maximum deflection. Also, when the same amount of light is incident on photoelectric sensors A and B, arrow 2 generated from photoelectric sensors A and B
Since the photocurrents in one direction and in the direction of arrow 21' are equal, they cancel each other out, and the photocurrent difference meter 6c displays an indication that the photocurrent difference is zero. In this way, the photocurrent difference displayed on the photocurrent difference meter 6c due to the respective photocurrents flowing in the closed circuit 14 in response to the light incident on the photoelectric sensors A and B can be determined by moving the passing beam 19. The photocurrent difference characteristics as shown in FIG. 8 are shown. In FIG. 8, the vertical line 23 corresponds to the photocurrent difference generated from photoelectric sensor A and photoelectric sensor B, and the horizontal axis 24 indicates the upper and lower positions of the cut line of the passing beam with respect to photoelectric sensors A and B. It shows. That is, FIG. 8 shows that the photocurrent difference on both sides of the photocurrent difference maximum value point 26 of the photocurrent difference waveform 25 gradually decreases and reaches the photocurrent difference zero points 27 and 27'. When the photocurrent difference reaches the zero point 27, it is when a passing beam of equal illuminance is incident on the photoelectric sensors A and B, and when the photocurrent difference reaches the zero point 27', the photoelectric sensors A and B are exposed to each other. This is when no passing beam is incident.
Then, when the photocurrent difference reaches the maximum value point 26, the passing beam hardly enters the photoelectric sensor A and exclusively enters the photoelectric sensor B. FIG. 9 shows the photocurrent characteristics of the photoelectric sensor. The vertical axis 28 represents photocurrent, and the horizontal axis 29 corresponds to the vertical position of the screen 5. In FIG. 9, when almost no beam is incident on photoelectric sensor A and a beam is incident on photoelectric sensor B, region 30 is photoelectric sensor B when the light receiving surface of photoelectric sensor B occupies area 32B of horizontal axis 29. The area 31 indicates the amount of photocurrent output from the photoelectric sensor A when the light receiving surface of the photoelectric sensor A occupies the area 32A of the horizontal axis 29.
This shows the amount of photocurrent output from the .

The inspector manually rotates the dial of the angle meter 7b to move the passing beam 19 vertically with respect to the screen 5, that is, to scan the passing beam 19 on the screen 5, which is displayed on the photocurrent difference meter 6c. When the maximum value of the photocurrent difference is found, the rotation of the dial of the angle meter 7b is stopped and the rotation angle of the mirror 3 corresponding to the amount of movement of the passing beam at that time is read from the angle meter 7b. The downward angle of the cut line 20 can be measured.

Next, another embodiment of the present invention will be described.
The device of this embodiment uses photoelectric sensors A and B in the previous embodiment.
are connected as shown in Figure 3, and the inspector detects the maximum value of the difference between the photocurrents output from each photoelectric sensor while visually checking the photocurrent difference meter. It is characterized by automatically measuring the position of the cut line or the downward angle. As shown in the perspective view of FIG.
4a and 34b, servo motors 35a and 35
b, gears 36a, 36a', 36b, 36b', rotating shafts 37a and 37b, limit switch 3
8a and 38b, and as shown in the block diagram in FIG.
b, peak signal detection section 40, peak position detection section 41, display sections 42a and 42b, amplifier 43a,
43b, 43c, photoelectric sensors A, B, C, D,
E and F are configured.

As shown, the servo motor 35a is driven and rotated by a signal from the motor control section 39a. A gear 36a is provided on the rotating shaft of the servo motor 35a.
The gear 36a is provided with a dog 44, which is arranged so as to be able to come into contact with the limit switch 38a or 38b by rotation of the servo motor 35a. This gear 36a is the gear 3
6a' so that power can be transmitted, and the gear 36
a' can be rotated at a predetermined number of rotations by rotation of the gear 36a. A rotary shaft 37a functioning as a feed screw is pivotally supported at the center of rotation of the gear 36a', and the shaft 37a is rotated integrally with the rotation of the gear 36a'. A sliding contact 45a of a potentiometer 34a is attached to the rotating shaft 37a, and is movable in the vertical direction by rotation of a servo motor 35a. The potentiometer 34a is configured to convert a change in the position of the sliding contact 45a into an electrical signal. The sliding contact 45a is connected to the screen 33 via a connecting member, and has a mechanism that moves the screen 33 in the vertical direction in conjunction with the vertical movement of the sliding contact 45a. Like the servo motor 35a, the servo motor 35b can also be driven and rotated by a signal from the control section, and a gear 36b is attached to the shaft of the motor 35b. Servo motor 3
5b, gears 36b and 36b', rotating shaft 37
b, sliding contact 45b, potentiometer 34
b has a similar configuration to the above-mentioned series of mechanisms, but
The difference is that the screen 33 is moved left and right. Further, the screen 33 has photoelectric sensors A, B,
C, D, E, and F are arranged in the same manner as in the previous embodiment.

As shown in FIG. 11, the photoelectric sensors C and D are connected to an amplifier 43b, and the amplifier 43b amplifies the difference between the photocurrents output from the photoelectric sensors C and D and outputs it to the motor control section 39b. There is a structure. Amplifier 43b and motor control section 39b
A switch 46 is provided between them, allowing selective connection between the amplifier 43b and the motor control section 39b. The motor control section 39b is an amplifier 43
The configuration is such that the servo motor 35b is operated until the difference between the photocurrents output from the servo motor 35b becomes zero, and a signal is output to the servo motor 35b to move the screen 33 in the left-right direction so as to track the vertical optical axis of the traveling beam. . Further, the potentiometer 34b outputs signals indicating the distance that the screen 33 has moved in the left-right direction and the position of the screen 33 due to the operation of the servo motor 35b to the display section 42a. In FIG. 11, the experiments in which blocks are connected represent electrical connections, and dotted lines represent mechanical connections. The photoelectric sensors E and F are connected to an amplifier 43a, and the amplifier 43a is configured to amplify the difference in photocurrent and output it to a terminal 47.
The motor control section 39a is connected to the terminal 4 by the switch 49.
7 or 48. Like the motor control section 39b, the motor control section 39a is configured to output a signal to the servo motor 35a to operate the servo motor 35a until the difference between the photocurrents output from the photoelectric sensors E and F becomes zero. Due to the operation of the servo motor 35a, signals indicating the distance that the screen 33 has moved in the vertical direction and the position of the screen 33 are sent to the potentiometer 34a.
When the switch 50 is connected to the terminal 51, it passes through the peak position detection section 41 and the display section 4
The configuration is shown in 2b. When the motor control section 39a is connected to the terminal 48 by the switch 49, the gear 36a connected to the motor 35a rotates due to the operation of the servo motor 35a, and the dog 44 performs a planetary motion accordingly. When the servo motor 35a comes into contact with the servo motor 35a, the limit switch 38a and the motor control section 39a output a signal to the servo motor 35a to reverse the rotational direction of the servo motor 35a. Therefore, the servo motor 35a operates with the rotation direction reversed, and the dog 44 moves in the opposite direction with the rotation, and the limit switch 3
8b and outputs a signal to the servo motor to reverse the rotational direction of the servo motor in the same manner as described above, and this operation is repeated.

Photoelectric sensors A and B are connected in the same way as in the previous embodiment, but instead of an ammeter, an amplifier 43c is inserted into the closed circuit formed by photoelectric sensors A and B, and the amplifier 43c is connected to the peak signal detection section 40. has been done. In the amplifier 43c, the difference between the photocurrents output from the sensors A and B is amplified and output to the peak signal detection section 40. The peak signal detection unit 40 is configured to detect the maximum point of the photocurrent difference waveform 25, that is, the peak of the waveform 25 as shown in FIG. 8, and output a peak hold signal to the terminal 52 when the peak is detected It is becoming. switch 50
When the terminal 52 and the peak position detection unit 41 are connected by the switch 49 and the terminal 48 and the motor control unit 39a are connected by the switch 49, the potentiometer 34 is connected in the peak position detection unit 41.
The position signal of the screen 33 in the vertical direction outputted from a and the peak hold signal outputted from the terminal 52 are combined to detect the position of the screen 33 when the photocurrent difference is maximum, and the position signal at that time is displayed. The configuration is such that the signal is output to the section 42b.

Next, the operation of the device of this embodiment will be explained.
The entire apparatus is arranged so that the screen 33 is located at an appropriate position in front of the headlamp 9. Then, the switch 46 connects the amplifier 43b and the motor control section 39b, the switch 49 connects the terminal 47 and the motor control section 39a, and the switch 50 connects the terminal 51 and the peak position detection section 4.
Connect with 1.

Next, the screen 33 is irradiated with the running beam 16 from the headlamp 9. Therefore, the photoelectric sensor C,
A traveling beam is incident on D, E, and F, and photocurrents are output from the respective photoelectric sensors to amplifiers 43a and 43b, and the photocurrent difference is amplified and motor controllers 39a and 3
It is output to 9b. Motor control section 39a, 39b
Then, a signal is output to the servo motors 35a, 35b to operate the servo motors 35a, 35b so as to make the input photocurrent difference zero. For this reason, the first
As shown in FIG. 0, the servo motors 35a and 35b drive and rotate to move the sliding contacts 45a and 45b in the vertical and vertical directions so as to track the vertical optical axis 18 and horizontal optical axis 17 of the traveling beam 16 via gears and rotating shafts. Move left and right. That is, the screen 33 is aligned vertically or horizontally with reference horizontal line 12 and reference vertical line 11 of the screen as shown in FIG.
is moved by rotation of the servo motors 35a and 35b until it coincides with the horizontal optical axis and the vertical optical axis of the traveling beam 16. When the photocurrent difference output from the photoelectric sensor becomes zero, alignment between the optical axis of the traveling beam 16 and the screen 33 is completed, and the servo motor stops operating. Depending on the positions of the sliding contacts 45a, 45b at this time, vertical and horizontal position signals of the screen 33 are displayed on the display sections 42a, 42b from the potentiometers 34a, 34b.

Next, the switch 46 cuts off the connection between the amplifier 43b and the motor control section 39b, and the switch 49
The motor control unit 39a and the terminal 48 are connected by the switch 50, and the peak signal detection unit 40 and the peak position detection unit 41 are connected by the switch 50.
Incidentally, it is preferable to provide a changeover switch for simultaneously performing such switching. Next, head lamp 9
From the running beam 16 to the passing beam 19
to operate the servo motor 35a.

For this reason, the dog 44 attached to the gear 36a
limit switch 38a or 38b by rotation of
When the dog 44 contacts the limit switch, a servo motor reversal signal is output to the servo motor 35a via the motor control unit 39a, and the servo motor 35a repeats reversal at a period corresponding to the contact period of the dog 44 to the limit switch, and the screen 33 moves in the vertical direction. make a reciprocating motion. When the screen 33 moves back and forth in the vertical direction, a passing beam 19 enters the photoelectric sensors A and B, and passes through the amplifier 43c to the peak signal detection unit 40.
As the screen 33 moves up and down, the eighth
A photocurrent difference that changes like a photocurrent difference waveform 25 shown in the figure is input, and a predetermined signal is output to the peak position detection section 41 when the photocurrent difference is at its maximum, that is, at its peak. At this time, the peak position detection unit 41 detects the screen position signal that is changing every moment due to the reciprocating movement of the screen 33 and detects the position signal on the potentiometer 3.
4a, the screen position signal is detected at the peak of the photocurrent difference, and the screen position signal is input to the display section 42.
It is output to b. From the position signal displayed at this time, the downward angle of the passing beam or the cut line position from the reference horizontal line can be measured.

As described in detail above, according to the apparatus of the present invention, it is possible to accurately measure the downward angle or cut line position of the passing beam projected from the headlights of an automobile. It is also possible to perform alignment using the traveling beam and measuring the downward angle of the passing beam on the same screen.
According to the apparatus of the present invention, the cut line position in the passing beam mode can be measured in the form of relative position information with respect to the main optical axis position detected in the traveling beam mode, which is of practical significance.

In the embodiment of the present invention, the measurement of the downward angle of the passing beam for left-hand traffic has been described, but it is also possible to measure the downward angle of the passing beam for right-hand traffic using the apparatus of the present invention. As described above, the present invention is not limited to the specific embodiments described above, and it goes without saying that various modifications can be made within the technical scope of the present invention.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing a measuring device according to an embodiment of the present invention, Fig. 2 is a schematic diagram showing a screen, Figs. 3 and 4 are circuit diagrams showing the connection of a photoelectric sensor, and Fig. 5 is a schematic diagram showing a photoelectric sensor. A block diagram showing how the photocurrent output from the sensor is controlled, Fig. 6 is an isoluminance curve diagram of a traveling beam, Fig. 7 is an isoluminance curve diagram of a passing beam, and Fig. 8 is a graph showing the photocurrent difference. 9 is a graph showing the photoelectric characteristics of a photoelectric sensor, FIG. 10 is a perspective view showing an automatic measuring device according to an embodiment of the present invention, and FIG. 11 is a block diagram regarding the automatic measuring device shown in FIG. 10. , is. (Explanation of symbols), 1: Dark box, 2: Condensing lens,
3: Mirror, 5, 33: Screen, 6a, 6
b, 6c: Photocurrent difference meter, 7a, 7b: Angle meter (dial), 9: Head lamp, 16: Traveling beam,
19: Passing beam, 25: Photocurrent difference waveform, 3
4a, 34b: potentiometer, 35a, 35
b: Servo motor, 36a, 36a', 36b, 3
6b': Gear, 37a, 37b: Rotating shaft (feed screw), 38a, 38b: Limit switch, 44: Dog, 45a, 45b: Sliding contact, A, B, C, D, E, F: Photoelectric sensor .

Claims (1)

[Scope of Claims] 1. A headlight beam measurement device that measures the cut line position of a passing beam of an automobile headlight that can be switched between a running beam mode and a passing beam mode, with reference to the main optical axis position of the running beam, a screen whose position is variable relative to the irradiation beam, a main optical axis photoelectric detection means for detecting the position of the main optical axis of the traveling beam, and a predetermined relative position with respect to the main optical axis photoelectric detection means. cut-line photoelectric detection means disposed on the screen in a specific positional relationship and detecting the cut-line position of the passing beam, an adjustment amount of the cut-line photoelectric detection means from the state at the end of the main optical axis detection operation, and the predetermined A headlight beam measuring device comprising means for providing information on the cut line position based on a predetermined relative positional relationship. 2. In claim 1, the cut line photoelectric detection means has a pair of photoelectric sensors, each of which has two positive and negative electrodes, and the electrodes of the same polarity are connected to each other. A headlight beam measuring device characterized by configuring a closed circuit. 3. In claim 1, the main optical axis photoelectric detection means has a plurality of photoelectric sensors, including four photoelectric sensors arranged axially symmetrically with respect to an axis substantially parallel to the main optical axis. A headlight beam measuring device characterized by having a photoelectric sensor. 4 In claim 1 or 2,
A headlight beam measuring device characterized in that the photoelectric sensor is placed in a dark box equipped with a condensing lens, and the irradiation beam is made to enter the screen via the condensing lens. 5. According to any one of claims 1 to 4, the irradiation beam is reflected by a mirror and is incident on the screen to displace the irradiation beam relative to the screen. A headlight beam measurement device. 6. In claim 5, the mirror is provided to be movable relative to the irradiation beam, and by changing the relative positional relationship of the mirror with respect to the irradiation beam, the traveling beam A headlight beam measuring device characterized in that the position of the main optical axis of the headlight beam and the position of the cut line of the passing beam are detected. 7. Claim 1, further comprising: a servo motor that reciprocates the cut line photoelectric detection means in a predetermined direction; and a peak detector that detects the maximum value of the output from the cut line photoelectric detection means;
A headlight beam measuring device comprising: a cutline position detector for detecting a cutline position of a passing beam based on a signal from the peak detector and a signal representing the position of the main optical axis.