JP5543937B2 - Vehicle headlamp - Google Patents

Description

  The present invention relates to a vehicle headlamp.

  2. Description of the Related Art Conventionally, as a vehicle headlamp such as an automobile headlight, a so-called projector type lamp is known in which light emitted from a bulb is reflected by a reflector and projected to the front of the vehicle by a projection lens.

  In this projector-type vehicle headlamp, the bulb is inserted and fixed from the rear side of the reflector with the bulb extending in the front-rear direction along the optical axis of the projection lens extending in the front-rear direction. The structure was common. In recent years, a vehicular headlamp having such a structure has a structure in which the lamp is made compact in the front-rear direction by adopting a structure in which the bulb is inserted and fixed to the reflector from the side so as to be orthogonal to the optical axis. It has been proposed (see, for example, Patent Document 1).

  By the way, in the reflective surface of a reflector, the optical axis side area | region located in the side of an optical axis is suitable for forming the diffusion pattern with a comparatively large diffusion angle among light distribution patterns. Therefore, in the above structure in which the bulb is inserted into the reflector from the side, if the bulb insertion hole is provided in the optical axis side region of the reflecting surface, the optical axis side region cannot be used as the reflecting surface. The brightness of the diffusion pattern cannot be ensured.

  Therefore, in the vehicle headlamp described in Patent Document 2, as shown in FIG. 8, the reflector 90 is disposed from the side (right side) while the bulb 90 is spaced downward from the optical axis Ax of the projection lens (not shown). By inserting and fixing to 91, the bulb insertion hole is spaced downward from the optical axis side region of the reflecting surface 91a of the reflector 91, and the optical axis side region can be used as a reflecting surface.

  Specifically, in the vehicle headlamp described in Patent Document 2, the reflection surface 91a includes an upper reflection area Z1 that includes the optical axis side area and is formed above the optical axis Ax, and the lower left and right sides. The lower central reflection area Z2 formed in the center of the direction and the lower left reflection area Z3 formed on the left side of the lower central reflection area Z2 are defined. As shown in FIG. 9, among the light distribution pattern (low beam) PL, the diffusion pattern P1 is formed by the upper reflection region Z1, and the light collection pattern P2 having a smaller diffusion angle than the diffusion pattern P1 is formed in the lower central reflection region Z2. The intermediate pattern P3 having an intermediate diffusion angle between the diffusion pattern P1 and the light collection pattern P2 is formed by the lower left reflective region Z3. At this time, the diffusion patterns P1, the condensing pattern P2, and the intermediate pattern P3 all have substantially uniform diffusion angles to the left and right.

Japanese Utility Model Publication No. 2-47704 JP 2008-91350 A

  However, in the vehicle headlamp described in Patent Document 2, the lower left reflective area Z3 that forms the intermediate pattern P3 is disposed on the left side of the optical axis Ax of the projection lens, so that the intermediate pattern P3 is diffused. It is extremely difficult to form such that the angles are equal to the left and right. That is, since the lower left reflective area Z3 is shifted to the left side with respect to the optical axis Ax, when the reflected light from the lower left reflective area Z3 is inverted and projected by the projection lens, the lower left reflective area Z3 is directed toward the center of the light distribution pattern PL. The intermediate pattern P3r approaching the right side is formed, and as a result, the light distribution pattern PL cannot be formed properly.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the vehicle headlamp which can form a light distribution pattern appropriately in the structure which inserted the valve | bulb from the side of the reflector.

In order to solve the above-mentioned problem, the invention described in claim 1
A projection lens having an optical axis along the front-rear direction;
A valve having a valve shaft disposed behind the projection lens and spaced downward from the optical axis and extending substantially along the left-right direction;
A light-shielding plate disposed between the projection lens and the bulb;
A reflector having a reflecting surface that is disposed so as to cover the bulb from the rear and reflects the light emitted from the bulb forward;
In a vehicle headlamp that forms a predetermined light distribution pattern on the front side of the vehicle as a combined pattern including a condensing pattern, a diffusion pattern, and an intermediate pattern,
The reflective surface of the reflector is
The optical axis is disposed so as to be positioned at the approximate center in the left-right direction,
An upper central region that is above the optical axis and is located at the approximate center in the left-right direction, an upper peripheral region that includes both lateral portions of the upper central region in the left-right direction, and a lower side that is below the optical axis and is A lower central region located approximately in the center of the direction,
The upper central region is a reflective region for forming the condensing pattern, the upper peripheral region is a reflective region for forming the diffusion pattern, and the lower central region is for forming the intermediate pattern A reflection area,
A first additional reflecting surface is formed on the rear surface of the light shielding plate,
A second additional reflecting surface is formed on the left or right side of the reflector and in front of the bulb in the valve axial direction.
The first additional reflection surface is formed in an elliptical surface having a first focal point in the vicinity of the light emitting portion of the bulb and a second focal point at a predetermined position between the light shielding plate and the second additional reflection surface,
The second additional reflection surface has a vertical cross-sectional shape orthogonal to the left-right direction, and an ellipse having the second focal point of the first additional reflection surface as the first focal point and the vicinity of the rear edge of the light shielding plate as the second focal point. A horizontal cross-sectional shape perpendicular to the vertical direction is formed in a parabolic shape with a focus on the vicinity of the second focal point of the first additional reflection surface,
The reflected light that is emitted from the bulb and passes through the first additional reflective surface and the second additional reflective surface forms a side pattern that irradiates the side of the light distribution pattern .

  Here, the condensing pattern is a partial pattern that is relatively condensed in the center of the predetermined light distribution pattern, and the diffusion pattern is a partial pattern that is diffused wider than the condensing pattern, The intermediate pattern is a partial pattern having an intermediate diffusion degree between the condensing pattern and the diffusion pattern.

The invention according to claim 2 is the vehicle headlamp according to claim 1,
The upper central region has a horizontal direction with respect to the optical axis so that the condensing pattern is formed slightly closer to the own lane side than the horizontal center corresponding to the optical axis in the predetermined light distribution pattern. Leaning toward
The upper peripheral region and the lower central region are formed substantially symmetrically with respect to the optical axis so that the diffusion pattern and the intermediate pattern are formed substantially symmetrical with respect to the predetermined light distribution pattern. It is characterized by being.
The invention according to claim 3 is the vehicle headlamp according to claim 2,
The reflector is configured such that the upper central region of the reflecting surface is rotatable about a central axis along the vertical direction.

  According to the present invention, the reflecting surface of the reflector is disposed so that the optical axis is positioned at substantially the center in the left-right direction, and the reflecting surface is below the optical axis and substantially in the left-right direction. Since the intermediate pattern of the light distribution pattern is formed by the lower central region located in the center, unlike the conventional case where the reflection region for forming the intermediate pattern is arranged on the left side of the optical axis, it is on the optical axis. The intermediate pattern can be formed so that the diffusion angle with respect to the center line is substantially equal to the left and right. In addition, a condensing pattern is formed by the upper central region located above the optical axis and approximately at the center in the left-right direction, and is diffused by the upper peripheral region including both the left and right sides of the upper central region. Since the pattern is formed, the light collection pattern and the diffusion pattern can be appropriately formed so that the diffusion angles are substantially equal to the left and right. Therefore, in a configuration in which the bulb is inserted from the side of the reflector so that the bulb shaft extends substantially along the left-right direction, a light distribution pattern, which is a combined pattern of the light collection pattern, diffusion pattern, and intermediate pattern, is formed appropriately. can do.

It is a perspective view of the vehicle headlamp in an embodiment. It is a sectional side view of the vehicle headlamp in an embodiment. It is a front view of the principal part of the vehicle headlamp in an embodiment. It is a perspective view of the important section of the vehicular headlamp in an embodiment. It is a figure which shows each partial pattern and light distribution pattern which are formed on the virtual screen ahead of a vehicle with the vehicle headlamp in embodiment. It is a perspective view of the principal part of the modification of the vehicle headlamp in embodiment. It is a figure which shows each partial pattern and light distribution pattern which are formed on the virtual screen ahead of a vehicle by the modification of the vehicle headlamp in embodiment. It is a front view of the principal part of the conventional vehicle headlamp. It is a figure which shows the light distribution pattern formed on the virtual screen ahead of a vehicle with the conventional vehicle headlamp.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a vehicle headlamp 1 according to the present embodiment, FIG. 2 is a side sectional view of the vehicle headlamp 1, and FIG. 3 is a main portion of the vehicle headlamp 1. FIG. 4 is a perspective view of the main part of the vehicle headlamp 1.
In the following description, unless otherwise specified, the descriptions of “front”, “rear”, “left”, “right”, “upper”, and “lower” refer to the direction viewed from the vehicle headlamp 1, It shall be used corresponding to the description in the drawing.

As shown in FIGS. 1 and 2, a vehicle headlamp 1 is a projector type that is mounted on a vehicle (not shown) and forms a low beam as a light distribution pattern in front of the vehicle, and includes a projection lens 2 and a bulb 3. A reflector 4, a shade 5, and a sub-reflector 6.
Among these, the projection lens 2 is a plano-convex lens having a convex front surface, and has an optical axis Ax along the front-rear direction. The projection lens 2 reversely projects an image on the focal plane including the rear focal point f1 on the optical axis Ax forward.

  The bulb 3 is an HID (high pressure discharge) lamp having a light emitting portion 31 and is arranged so that the bulb axis Ax1 extends substantially along the left-right direction. More specifically, the bulb 3 is located on the right side so that the rear focal point f1 of the projection lens 2 is behind and below the optical axis Ax, and the light emitting unit 31 is located directly below the optical axis Ax. Is inserted into the reflector 4 along the left-right direction, and is fixed to a later-described valve support 42 provided on the reflector 4.

  The reflector 4 is formed in a curved concave plate shape that opens forward, and is disposed so as to cover the bulb 3 from the rear. A valve support 42 that supports the base end of the bulb 3 is provided on the right side below the optical axis Ax in the front surface of the reflector 4. Further, the reflector 4 has a shape in which a portion located in front of the direction along the valve axis Ax1 of the bulb 3 (hereinafter referred to as the valve axis Ax1 direction), that is, a left side portion below the optical axis Ax is cut away. Is formed.

Of the front surface of the reflector 4, a portion excluding the right side portion where the valve support portion 42 is provided is a reflection surface 41 based on a spheroid. The reflection surface 41 reflects the light emitted from the bulb 3 forward toward the focal plane including the rear focal point f1 of the projection lens 2. As shown in FIGS. 3 and 4, the reflecting surface 41 is disposed so that the optical axis Ax is positioned at the approximate center in the left-right direction and the up-down direction, and is above the optical axis Ax and substantially the same. In the lower half, the upper central region Ra located substantially in the center in the left-right direction, the upper peripheral region Rb composed of the upper portion of the upper central region Ra and both side portions in the left-right direction, and below the optical axis Ax. And a lower central region Rc located substantially at the center in the left-right direction. Accordingly, the upper central region Ra, the upper peripheral region Rb, and the lower central region Rc are formed so as to be substantially equal to the left and right with respect to the vertical plane including the optical axis Ax. However, the upper central region Ra is inclined slightly to the right with respect to the optical axis Ax, and the upper peripheral region Rb and the lower central region Rc are formed substantially symmetrically with respect to the optical axis Ax. Yes. These upper middle region Ra, the upper peripheral region Rb and the lower central region Rc, as described later, the light converging pattern Pa, the reflection region for forming each diffusion pattern Pb and the intermediate pattern Pc of the low beam P _L (See FIGS. 5A to 5C and 5E).

As shown in FIGS. 1 and 2, the shade 5 is a light shielding plate erected so as to be orthogonal to the optical axis Ax, and the projection lens in a state where the vertical position of the upper end edge substantially coincides with the optical axis Ax. 2 and the valve 3. As for this shade 5, the upper end part 51 of the center in the left-right direction is bent back. The upper end 51 has the rear focal point f1 of the projection lens 2 in the vicinity of the rear end edge 51a, and the rear end edge 51a extends along the focal plane including the rear focal point f1 of the projection lens 2 along the optical axis. As it moves away from Ax to the left and right sides, it is curved so as to be positioned forward. The upper end of the rear edge 51a has a bending point 51b located on the optical axis Ax, and is formed in a stepped shape slightly higher on the left side than the bending point 51b. With such a configuration, the shade 5 shields a part of the light reflected by the reflecting surface 41 of the reflector 4, and as an inverted image of the rear end edge 51a, the elbow portion E at the center in the left-right direction corresponding to the bending point 51b. the cut-off line C _L which right is formed lower forms the upper edge of the low beam P _L than (see FIG. 5 (e)).

  A first additional reflection surface 52 is formed on the rear surface of the shade 5. The first additional reflection surface 52 is formed in a spheroid shape in which the vicinity of the light emitting unit 31 is a first focal point f2, and a predetermined position between the shade 5 and the sub reflector 6 is a second focal point (not shown). Yes. The first additional reflection surface 52 reflects the light emitted from the bulb 3 obliquely leftward and backward toward the front of the bulb 3 in the direction of the bulb axis Ax1.

  The sub-reflector 6 is disposed on the left side of the reflector 4 and substantially in front of the bulb 3 in the direction of the valve axis Ax1, and the front surface thereof is a second additional reflection surface 61. The second additional reflection surface 61 is an ellipse having a vertical cross-sectional shape orthogonal to the left-right direction, the second focus of the first additional reflection surface 52 being the first focus, and the vicinity of the rear end edge 51a of the shade 5 being the second focus. The horizontal cross-sectional shape orthogonal to the up-down direction is formed in a parabolic shape having a focus in the vicinity of the second focal point of the first additional reflection surface 52. Therefore, the second additional reflection surface 61 reflects the light reflected by the first additional reflection surface 52 forward so as to be condensed in the vicinity of the rear end edge 51a of the shade 5 in the vertical direction, and substantially in the horizontal direction. It is reflected forward so that it becomes parallel light.

Next, formation of a light distribution pattern (low beam) by the vehicle headlamp 1 will be described.
FIGS. 5A to 5E are diagrams showing each partial pattern and light distribution pattern formed on the virtual screen in front of the vehicle by the vehicle headlamp 1.

  In the vehicle headlamp 1, when the light emitting unit 31 of the bulb 3 emits light, the light emitted from the light emitting unit 31 and incident on the reflecting surface 41 of the reflector 4 is reflected forward by the reflecting surface 41. The shade 5 is partially shielded from light, and is reversely projected forward through the projection lens 2.

At this time, the reflected light at each reflection area of the reflecting surface 41, FIG. 5 (a) ~ (c) , as shown in (e), a partial pattern of a low beam P _L individually. Specifically, the reflected light from the upper central region Ra forms a light collection pattern Pa (FIG. 5A) that is relatively condensed at the center, and the reflected light from the upper peripheral region Rb is collected. A diffusion pattern Pb (FIG. 5B) that is diffused wider than the light pattern Pa was formed, and the reflected light at the lower central region Rc was set to an intermediate degree of diffusion between the light collection pattern Pa and the diffusion pattern Pb. An intermediate pattern Pc (FIG. 5C) is formed. Among these, the condensing pattern Pa by the reflected light in the upper central area Ra is a high luminous intensity area formed in the vicinity of the elbow part E of the cut-off line C _{L in} the low beam P _L , and the upper central area that is oriented slightly to the right. Corresponding to the region Ra, it is formed slightly closer to the left side (own lane side) than the center in the left-right direction (position on the vertical line V) corresponding to the optical axis Ax. Further, the diffusion pattern Pb and the intermediate pattern Pc by the reflected light in the upper peripheral region Rb and the lower central region Rc are formed so that the upper peripheral region Rb and the lower central region Rc are substantially symmetrical with respect to the optical axis Ax. Therefore, it is formed in a substantially bilaterally symmetric shape in the low beam P _L.

  Here, the condensing pattern Pa, the diffusion pattern Pb, and the intermediate pattern Pc are such that the upper central region Ra, the upper peripheral region Rb, and the lower central region Rc for forming these partial patterns are on a vertical plane including the optical axis Ax. Since they are formed so as to be substantially equal to the left and right, respectively, the diffusion angles with respect to the center line on the optical axis Ax are formed so as to be substantially equal to the left and right.

On the other hand, of the light emitted from the light emitting unit 31 of the bulb 3, the light incident on the first additional reflection surface 52 on the rear surface of the shade 5 is reflected backward by the first additional reflection surface 52, and the sub reflector 6 The light is reflected forward by the two-addition reflecting surface 61 and is reversely projected forward through the projection lens 2. Light reflection at the second additional reflection surface 61, as shown in FIG. 5 (d), to form a side patterns Pd irradiated on the right side of the low beam P _L.

Then, as a synthetic pattern or partial pattern Pa~Pd is superimposed, Figure 5 (e), the for left-hand traffic having a cut-off line C _L which right is formed lower than the horizontal center of the elbow portion E Low beam P _L is formed.

As described above, according to the vehicle headlamp 1, the upper central region Ra, the upper peripheral region Rb, and the lower central region Rc are formed so as to be substantially equal to the left and right with respect to the vertical plane including the optical axis Ax. Therefore, unlike the conventional case where the reflection region for forming the intermediate pattern is arranged on the left side of the optical axis, the diffusion angle of the intermediate pattern Pc as well as the condensing pattern Pa and the diffusion pattern Pb is substantially the same. Each of them can be formed to be equal to the left and right. Therefore, in the configuration in which the bulb 3 is inserted from the side of the reflector 4 so that the bulb axis Ax1 extends substantially along the left-right direction, the combined pattern includes the light collection pattern Pa, the diffusion pattern Pb, and the intermediate pattern Pc. A light distribution pattern (low beam P _L ) can be formed appropriately.

In addition, the upper central region Ra is inclined slightly to the right with respect to the optical axis Ax, and the upper peripheral region Rb and the lower central region Rc are formed substantially symmetrically with respect to the optical axis Ax. the reflector 4 for forming a low beam P _L for left-hand traffic, only the upper central region Ra of the reflecting surface 41 is inclined in the lateral direction. Therefore, by changing the upper central region Ra of the reflective surface 41 to a slightly inclined leftward direction, the left-hand traffic reflector 4 can be changed to the right-hand traffic reflector 4A.

Specifically, as shown in FIG. 6, the reflector 4A for right-hand traffic has a reflecting surface 41A instead of the reflecting surface 41 in the reflector 4, and the reflecting surface 41A is formed in the upper central region Ra. Instead, it has an upper central region RaA in which the upper central region Ra is inclined slightly to the left. According to such a reflector 4A, as shown in FIG. 7A, the reflected light from the upper central region RaA is slightly more than the horizontal center (position on the vertical line V) corresponding to the optical axis Ax. A condensing pattern PaA located on the right side is formed. Therefore, formation and the light collecting pattern PaA, diffusion pattern Pb shown in FIG. 7 (b) ~ (d) , as a synthesis pattern and intermediate pattern Pc and the side pattern Pd is superimposed, the low beam P _R for right-hand traffic can do. However, as not shown, at this time, instead of the cut-off line C _L of the low beam P _L, the cut-off line C _R for right-hand traffic the left is formed lower is formed than elbow portion E, Of course, it is necessary to change the shape of the rear end edge 51a of the shade 5.
Thus, the left-hand traffic reflector 4 can be changed to the right-hand traffic reflector 4A simply by turning the upper central region Ra of the reflecting surface 41 slightly to the left. Therefore, both the reflector 4A for left-hand traffic and the reflector 4A for right-hand traffic can be formed only by exchanging the insert for molding the upper central region in the reflector mold. The manufacturing cost of the mold can be reduced as compared with the case where the reflector mold is manufactured separately for the right side and the right side.

  The embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

For example, in the above embodiment, the vehicle headlamp 1 is decided to form a low beam P _L or low beam P _R as a light distribution pattern, a light distribution pattern vehicle headlamp 1 is formed may be a high beam Other light distribution patterns may be used.

Further, instead of the reflector 4 having the upper central region Ra tilted rightward, by using a reflector 4A having an upper central region RaA tilted leftward, low beam for right-hand traffic instead of the low beam P _L for left-hand traffic It was able to form a P _R, but by using a reflector 4 assumes pivotable about the center axis along an upper central region Ra in the vertical direction, even switchable between a low beam P _L and low beam P _R Good. According to such a reflector 4, the position of the condensing pattern Pa is moved in the left-right direction by the rotation of the upper center region Ra in the left-right direction, so that the low-passage P _L for left-hand traffic and the low-beam P for right-hand traffic _R can be switched appropriately. In this case, however, the shape of the rear end edge 51a of the shade 5 needs to be changed in accordance with the change of the low beam.

  Further, the bulb 3 is not limited to the HID lamp, and may be a halogen lamp, for example.

DESCRIPTION OF SYMBOLS 1 Vehicle headlamp 2 Projection lens Ax Optical axis 3 Bulb 31 Light emission part Ax1 Bulb axis | shaft 4, 4A Reflector 41, 41A Reflecting surface Ra, RaA Upper center area Rb Upper peripheral area Rc Lower center area 5 Shade 51 Upper end 51a Rear Edge 51b Bending point 52 First additional reflection surface 6 Sub reflector 61 Second additional reflection surface P _L , P _R Low beam Pa, PaA Condensing pattern Pb Diffusion pattern Pc Intermediate pattern Pd Side pattern C _L , C _R Cut-off line E Elbow club

Claims (3)

A projection lens having an optical axis along the front-rear direction;
A valve having a valve shaft disposed behind the projection lens and spaced downward from the optical axis and extending substantially along the left-right direction;
A light-shielding plate disposed between the projection lens and the bulb;
A reflector having a reflecting surface that is disposed so as to cover the bulb from the rear and reflects the light emitted from the bulb forward;
In a vehicle headlamp that forms a predetermined light distribution pattern on the front side of the vehicle as a combined pattern including a condensing pattern, a diffusion pattern, and an intermediate pattern,
The reflective surface of the reflector is
The optical axis is disposed so as to be positioned at the approximate center in the left-right direction,
An upper central region that is above the optical axis and is located at the approximate center in the left-right direction, an upper peripheral region that includes both lateral portions of the upper central region in the left-right direction, and a lower side that is below the optical axis and is A lower central region located approximately in the center of the direction,
The upper central region is a reflective region for forming the condensing pattern, the upper peripheral region is a reflective region for forming the diffusion pattern, and the lower central region is for forming the intermediate pattern A reflection area,
A first additional reflecting surface is formed on the rear surface of the light shielding plate,
A second additional reflecting surface is formed on the left or right side of the reflector and in front of the bulb in the valve axial direction.
The first additional reflection surface is formed in an elliptical surface having a first focal point in the vicinity of the light emitting portion of the bulb and a second focal point at a predetermined position between the light shielding plate and the second additional reflection surface,
The second additional reflection surface has a vertical cross-sectional shape orthogonal to the left-right direction, and an ellipse having the second focal point of the first additional reflection surface as the first focal point and the vicinity of the rear edge of the light shielding plate as the second focal point. A horizontal cross-sectional shape perpendicular to the vertical direction is formed in a parabolic shape with a focus on the vicinity of the second focal point of the first additional reflection surface,
The vehicle is characterized in that the reflected light emitted from the bulb and passed through the first additional reflective surface and the second additional reflective surface forms a side pattern that is irradiated to the side of the light distribution pattern. For headlamps. The upper central region has a horizontal direction with respect to the optical axis so that the condensing pattern is formed slightly closer to the own lane side than the horizontal center corresponding to the optical axis in the predetermined light distribution pattern. Leaning toward
The upper peripheral region and the lower central region are formed substantially symmetrically with respect to the optical axis so that the diffusion pattern and the intermediate pattern are formed substantially symmetrical with respect to the predetermined light distribution pattern. the vehicle headlamp according to claim 1, characterized in that it is. The vehicle headlamp according to claim 2, wherein the reflector is configured such that the upper central region of the reflecting surface is rotatable about a central axis along the vertical direction.

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