JPH0625841Y2 - Projector type vehicle headlight - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a projector type automotive headlamp.

[Conventional technology]

The vehicle headlamp must have a light distribution pattern that brightly illuminates the front of the own lane and does not dazzle an oncoming vehicle.

A projector headlamp for a vehicle has been proposed as a headlamp that has a light distribution characteristic that meets the above requirements, has a simple lens configuration, and can be downsized in its overall shape. As the latest technology relating to this projector headlight, for example, JP-A-58-209801 is known.

FIG. 8 shows the above-mentioned known projector type headlight. The headlight of this known example is provided with a shell type reflector, and the cross section in the axial direction of the inner reflecting surface of this reflector forms a part of an ellipse, and the eccentricity of the ellipse is perpendicular to the axial direction. In a vehicle headlamp increasing from a longitudinal section to a horizontal axial longitudinal section, the elliptical portion of all axial sections
The focal points 105 of 101, 102 are also arranged such that the corresponding vertices 104 of the elliptical portions 101, 102 of all axial cross sections coincide.

110 is the outer focal point of the ellipse 102, 110 is a dimmer in the form of a shading plate, 112
Is an outer focus of the ellipse 101, and 113 is a lens.

FIG. 9 is a plan view schematically illustrating an example of this type of projector headlight, FIG. 10 is a side view of the same, and FIG. 11 is a front view of the same.

Reference numeral 1 is a concave mirror, and F is its focal point. The light source bulb 2 is provided so that the filament is located near the focal point F.

A convex lens 3 is provided so as to share the optical axis Z with the concave mirror 1.

Ij shown in FIG. 9 indicates the meridional image plane of the convex lens 3, and the light emitted from the light source and reflected by the concave mirror 1 is incident on this meridional image plane.

The incident light is dimmed by the convex lens 3 and projected forward (rightward in FIGS. 9 and 10).

A screen is provided in the vicinity of the original image plane, and the light distribution pattern is shown by isolux curves as shown in FIG.
H-H is a horizontal line on the screen, and V-V is a vertical line.

As shown in FIGS. 9 to 11, a shade 4 having an edge along the meridional image plane is provided. Specifically, as shown by 4a in FIG. 11, a cut line 4a is formed so as to recede downward from the horizontal section i-j of the meridional image plane. First
FIG. 12 shows how the above-mentioned light distribution pattern and the shade 4 overlap. As shown in FIG. 12, the upper half of the light flux passes through. Most of the lower half is blocked, but light is allowed to pass through the portion corresponding to the cutting line 4a.

Since the light beams partially covered as described above are condensed on the meridional image plane i-j and intersect each other, the light beam projected in front of the headlamp has a pattern of an inverted shape of FIG. To form. FIG. 13 is an explanatory view showing a schematic shape of a projection pattern by an isolux curve on a screen provided in front of the headlight.

This conventional example is configured for left-hand traffic, and in the case of right-hand traffic, FIGS. 11 to 13 are configured so that the left and right are different.

Assuming a case of traveling on a straight two-lane road while illuminating the front of the road with a headlight having a light distribution pattern as shown in FIG. 13, the V-V line in this figure is the center line of the road. Become parallel. Therefore, the vehicle traveling in the oncoming lane is located on the right side of the V-V line, and is not dazzled by the headlight of the vehicle on the other side.

However, when traveling on a curve with a left turn, the center line of the road appears to be curved to the left like a virtual line L. Therefore, an oncoming vehicle traveling along the center line L as indicated by the arrow enters the area illuminated by the headlights of our vehicle and is dazzled.

Further, in the case of a clockwise curve, the far side of the center line is curved to the right as indicated by the imaginary line R, so that the vicinity where the vehicle is going to travel along this is not illuminated as indicated by the arrow r.

In order to solve such a problem, it may be possible to support the headlight so that the headlight can be rotated right and left with respect to the vehicle body, but there is a drawback in that the device is complicated, large and heavy, and expensive.

In view of the above circumstances, a means for guiding the shade horizontally and at a right angle to the optical axis is provided so that the illuminated area can be freely operated in the left and right directions, and the shade is reciprocated in the above direction. A projector-type headlight provided with a driving means has been proposed (Japanese Utility Model Laid-Open No. 63-165703).
It is a prior application).

As described with reference to FIGS. 12 and 13, the upper part of the light distribution pattern of the illumination light flux (FIG. 13) above the line H-H is restricted, that is, the shade shadow is projected. Is. Therefore, when the shade is moved to the left or right according to the configuration of the prior application, the cutting line on the projected light beam distribution pattern moves to the left or right, and the illuminated area expands to the left or contracts to the right.

FIG. 14 shows an embodiment of a projector headlight according to the invention of the prior application, (A) is a plan view and (B) is a side view. In this figure, those denoted by the same reference numerals as in FIGS. 9 and 10 are the same or similar constituent members as in the above-mentioned conventional example.

Numeral 5 is a shade formed by applying the invention of the prior application, and a shade guide 6 is used for horizontal direction perpendicular to the optical axis (Fig. 14 (A)).
In the up and down direction, in the figure (B) the depth direction of the paper)
In addition, it is slidably supported.

While fixing the rack gear 7 to the shade 6,
A pinion gear 8 is meshed with the rack gear 7. 9
Is a motor for driving a pinion gear.

In this example, when the motor 9 is normally or reversely rotated, the shade 5 moves to the left and right in the irradiation direction (arrow Z).

FIG. 15 shows a light distribution pattern in this embodiment, which is VV
The line, the H-H line and the isolux curve are almost the same as in the conventional example (Fig. 13).

The cut line Cs on the light distribution pattern shown in FIG.
It shows the case where the shade 5 is positioned at the center (state of FIG. 14 (A)).

If you move the shade 5 to the right in the irradiation direction (arrow Z),
The cut line in Fig. 15 is an inverted image of Cr
As shown in the figure, the light distribution is such that it moves to the left and does not dazzle the oncoming vehicle in the counterclockwise curve.

Moreover, if the shade 5 is moved to the left in the irradiation direction,
The cutting line in FIG. 15 moves to the right as indicated by C, and the front of the traveling path of the own vehicle enters the illumination area in the clockwise curve.

[Problems to be solved by the device]

According to the projector headlight according to the invention of the prior application,
(Refer to FIG. 15) The cutting line can be arbitrarily operated like Cr to C to adapt to the road surface condition, and when there is no oncoming vehicle, the cutting line can be moved to the C'position and left and right 30 °. It is also possible to illuminate each of them, and to move the cutting line to the position of Cr 'so that the horizontal line H-H is not irradiated.

However, in the invention of the prior application, it is necessary to operate so as to appropriately move the cutting line while observing the illumination state in front of the traveling road surface, and it is not possible to automatically and instantaneously adjust to a preset irradiation pattern.

For this reason, there is a time delay in responding to a sudden change in the condition of the road, such as when the vehicle approaches a curved road or enters or exits a tunnel. Furthermore, it is dangerous to be distracted by adjusting the headlights when the road surface changes suddenly.

In view of the above-mentioned circumstances, the present invention has further improved the projector type headlight according to the prior application so that a desired light distribution pattern can be quickly and easily selected from a plurality of preset light distribution patterns by a simple operation. It is an object of the present invention to provide a projector type automotive headlight that can be selected.

[Means for Solving the Problems]

In order to achieve the above object, the present invention has a light source bulb installed near the focal point of a reflecting mirror, and the light emitted from the light source bulb is reflected by the reflecting mirror and focused near a shade having a cutting line to form a convex lens. In a projector-type headlight that projects the reflected light forward, by providing means for guiding the shade horizontally, in a direction perpendicular to the optical axis, and providing means for reciprocating the shade in the direction, Further, a plate-shaped member having a through hole is fixed to the shade, and a light-emitting element and a light-receiving element are arranged so as to face each other on both sides of the plate-shaped member, and these elements are provided to the projector type headlight. It is characterized by being fixed to the stationary member of.

[Action]

According to the above configuration, the shade is driven in the left-right direction, the cutting line of the shade moves left and right, and the light distribution pattern changes.

Since the plate member having the holes is fixed to the shade, the plate member having the holes moves left and right together with the shade.

Since the light emitting diode and the photodiode are opposed to each other with the perforated plate-shaped member sandwiched therebetween, light emitted from the light emitting diode and incident on the photodiode is blocked or not blocked by the perforated plate-shaped member. .

Installation position of the above light emitting diode and photo diode,
If the position of the hole in the plate member (specifically, the relative position of the hole with respect to the shade) is set beforehand in advance, the fact that the position of the shade in the left-right direction has reached the desired position is output from the photodiode. It can be detected by a signal.

〔Example〕

FIG. 3 is a plan view of an embodiment of the projector headlamp according to the present invention, which is cut and drawn.

The concave mirror 1, the light source bulb 2, the convex lens 3, and the shade 5 having the same drawing reference numbers as in the invention of the prior application are
The component is similar to that in the invention of the prior application, and Z is the optical axis.

A frame 10 supports the concave mirror 1 and the convex lens 3.

The guide rod 11 and the feed screw 12 are arranged vertically and horizontally with respect to the optical axis Z, and are supported by the bracket 13.

A motor 16 fixed to the frame 10 is configured to be able to drive the feed screw 12 forward and backward freely via a worm original gear 14 and a worm receiving gear 15.

Reference numeral 17 shown in the drawing is a square nut which is screwed onto the feed screw 12 and is guided by the guide rod 11 so as to be slidable in the vertical direction of the drawing.

The shade 5 is fixed to the square nut 17.

As a result, when the motor 16 is rotated in the forward or reverse direction, the shade 5 fixed to the square nut 17 is reciprocally driven up and down in the figure.

A vertical sectional view of this embodiment is shown in FIG. 1, and a front view thereof is shown in FIG.

Attach the shutter plate 20 to the square nut 20, as shown in FIG. The shutter plate 20 is provided with a through hole 20a as shown in FIG. The shutter plate 20 is provided with through holes other than the above through holes 20a, but it is hidden in FIG. The overall shape of the shutter plate 20 will be described later with reference to FIG.

As shown in FIG. 1, through the shutter plate 20, the phototransistor 18a, the LED 19a, and the phototransistor 18a are connected.
18b and LED 19b, phototransistor 18c and LED 19c,
The above-mentioned three pairs of photo couples are installed.

In FIG. 2, the three phototransistors 18a, 18 described above are shown.
The b and 18c overlap the three LEDs 19a, 19b and 19c.

In FIG. 2, when the feed screw 12 is rotated normally or reversely, the square nut 17 and the shade 5 fixed to the square nut 17 are moved left and right in the figure.

From the state shown in FIG. 2, when the shade 5 is moved leftward in the drawing by the dimension L, the shutter plate 20 is also moved leftward by the dimension L,
The through hole 20a provided in the shutter plate 20 faces the phototransistor 18a, and the through hole 20b faces the phototransistor 18b.

Phototransistor 18 that has received through-hole facing as described above
The a and 18b receive the light of the LEDs 19a and 19b.

Therefore, when the phototransistors 18a and 18b generate the detection signals, it can be known that the shade 5 is displaced to the left by the distance L.

When the shade 5 and the shutter plate 20 shown in FIG. 2 are extruded and drawn, it becomes as shown in FIG. 4 (A).

As shown in the figure, the shutter plate 20 has a position A in the left-right direction,
One through two holes are provided at positions B to F, respectively.

The through holes at the respective positions A to F have the levels h ₁ . One or two are provided according to either the level h _{2 of the} phototransistor 18b or the level h ₃ of the phototransistor 18c. This number of installations can be set arbitrarily.

In the state of FIG. 4 (A), the shade 5 is located at the center in the left-right direction, and the light distribution pattern in this state is shown in FIG.
Like (B). The through-hole at position B is a phototransistor 1
Faces 8a and 18c. The hatched portion in FIG. 4 (B) is the dark portion of the shade of the shade.

In the state of FIG. 5 (A), the shade 5 moves to the right of the figure,
Almost does not block the light flux. Therefore, the light distribution pattern is as shown in FIG.

In this state, the phototransistor 18c directly faces the through hole at the F position and outputs a light receiving signal.

Therefore, when only the phototransistor 18c outputs the photodetection signal, it is understood that the shade is located at the right end.

The phototransistor 18 is controlled by an automatic control device (not shown).
When the signal output of only c is detected, the motor 16 (Fig. 3)
When is stopped, the light distribution pattern of FIG. 5 (B) is obtained. This light distribution pattern is suitable for use when there are no oncoming vehicles, for example.

In the state shown in FIG. 6 (A), the shade 5 moves to the left in the figure and blocks the lower half of the light flux.

The light distribution pattern in that state is as shown in FIG. 6 (B), and almost no light is projected above the horizontal line H-H. In this state, the phototransistors 18a and 18b directly face the through hole at the position A and output a photodetection signal.

In the state shown in FIG. 7 (A), the maximum luminous flux density area in the vicinity of the intersection of the H line and the V line is not blocked.
A light distribution pattern as shown in (B) is obtained. In this state, C
It is understood that only the phototransistor 18a directly facing the through hole at the position outputs the photodetection signal.

When the shade 5 is stopped while the phototransistors 18b, 18b are outputting the photodetection signal through the through hole at the D position, a light distribution pattern closer to that of FIG. 5B than that of FIG. 7B is obtained.

By stopping the shade 5 with only the phototransistor 18b outputting the photodetection signal through the through hole at the E position, a light distribution pattern closer to that shown in FIG. 5B can be obtained.

According to this embodiment, the shade position can be known from the photodetection signals of the phototransistors 18a, 18b, 18c.

Utilizing this, the position of the shade 5 can be automatically controlled by an automatic control device (not shown) so as to be a preset desired position.

[Effect of device]

As described above, when the projector type headlight of the present invention is applied, a desired light distribution pattern can be quickly and easily selected from a plurality of preset light distribution patterns by a simple operation. it can.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a vertical sectional view, FIG. 2 is a partially cutaway front view, and FIG. 3 is a sectional plan view. 4 (A), (B), 5 (A), (B), 6 (A), (B), 7
Figures (A) and (B) are explanatory views of the operation of the above embodiment. FIG. 8 is an explanatory view of a known projector type headlight. 9 to 11 show a conventional projector type headlight, FIG. 9 is a plan view, FIG. 10 is a side view, and FIG. 11 is a front view. 12 and 13 are charts showing the optical characteristics of the above-mentioned conventional example. 14 (A), (B) and FIG. 15 are explanatory views of the device of the prior application. 1 ... concave mirror, 2 ... light source bulb, 3 ... convex lens, 4
…… Shade, 4a …… Cut line, 5 …… Shade,
18a-18c ... Phototransistors, 19a-19c ... LE
D, 20 ... Shutter plate.

Claims (1)

[Scope of utility model registration request] 1. A light source bulb is installed near a focal point of a reflecting mirror,
The light emitted from the light source bulb is reflected by a reflecting mirror and focused in the vicinity of a shade having a cutting line, in a projector-type headlamp that projects the reflected light forward by a convex lens, in the horizontal direction, A means for guiding in the direction perpendicular to the optical axis is provided, a means for reciprocating the shade in the direction is provided, and a plate-shaped member having a through hole is fixed to the shade, and the plate-shaped member A projector headlamp for a vehicle, characterized in that a light emitting element and a light receiving element are arranged facing each other and these elements are fixed to a stationary member of the projector headlamp.