JP2003168307A - Vehicular headlamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately irradiate a beam with a light distribution pattern conforming to a vehicle travelling condition, by an inexpensive and compact structure, in a vehicle headlamp provided with a lamp unit for low beam irradiation. <P>SOLUTION: A movable shade structured so as to be able to take a shielding position to shield a part of light entering into a reflector from a light source and a shielding releasing position to release it is provided in the low beam lamp unit. When a vehicle travels while turning toward an opposite traffic lane side, an auxiliary light distribution pattern P(B) having an oblique cut-off line CLb is added to the further upper side than the oblique cut-off line CL2 of a low beam light distribution pattern P(L) by moving the movable shade to the shielding releasing position to enhance visibility of the front in the turning direction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle headlamp including a lamp unit for low beam irradiation.

[0002]

2. Description of the Related Art Generally, a vehicle headlamp is configured to irradiate a beam forward with a predetermined light distribution pattern by a lamp unit having a light source and a reflector for reflecting light from the light source forward. ing.

At this time, in the lamp unit for low beam irradiation, beam irradiation is performed in a low beam light distribution pattern having a predetermined cut-off line at the upper edge so as not to give glare to an oncoming driver and the like. It is configured to ensure the front visibility of the car driver as much as possible.

[0004]

However, depending on the traveling condition of the vehicle, it may be difficult to obtain sufficient front visibility by beam irradiation from the lamp unit for low beam irradiation. For example, when the vehicle turns in the opposite lane, there is a problem that the front of the turning direction cannot be sufficiently illuminated.

On the other hand, if the direction of the lamp unit is changed or the direction of the reflector is partially changed, it is possible to perform beam irradiation with a light distribution pattern that immediately responds to the running condition of the vehicle. . However, in such a case, the rotating structure for partially changing the direction of the lamp unit and the direction of the reflector becomes large, and it is not easy to secure the installation space. There's a problem. Further, it is not easy to secure sufficient turning accuracy, and there is a problem that the turning structure becomes expensive in order to realize this.

The present invention has been made in view of the above circumstances, and in a vehicle headlamp including a lamp unit for low beam irradiation, the vehicle headlamp has an inexpensive and compact structure and can quickly respond to the running condition of the vehicle. It is an object of the present invention to provide a vehicle headlamp that can perform beam irradiation with a light distribution pattern with high accuracy.

[0007]

The present invention is intended to achieve the above-mentioned object by adopting a structure in which a predetermined auxiliary light distribution pattern can be additionally formed using a movable shade.

That is, the vehicular headlamp according to the present invention is a low beam light distribution pattern having a predetermined cut-off line at the upper edge by a lamp unit having a light source and a reflector for reflecting the light from the light source forward. In a vehicle headlamp configured to perform beam irradiation with,
A movable shade configured so as to have a shielding position for shielding a part of the light incident on the reflector from the light source and a shielding releasing position for releasing the shielding, and the movable shade for the shielding position and the shielding releasing position. And a shade driving device for moving the movable shade between them. When the movable shade is in the shielding position, beam irradiation is performed in the low beam light distribution pattern, while when the movable shade is in the shielding releasing position, the low beam is emitted. The auxiliary light distribution pattern having a cut-off line above the cut-off line of the light distribution pattern is added to the low beam light distribution pattern to perform beam irradiation.

The above-mentioned "lamp unit" is not particularly limited in its specific constitution as long as it has a light source and a reflector for reflecting the light from this light source forward, and the main light distribution by the reflector is provided. It may be configured to perform control, or may be configured to provide a lens in front of the reflector and perform main light distribution control by the lens.

The above-mentioned "light source" is not particularly limited in its specific constitution, and may be a discharge light emitting portion of a discharge bulb or a filament of an incandescent bulb such as a halogen bulb. Good.

If the "movable shade" is constructed so as to be able to take a shielding position and a shielding releasing position,
The specific configuration such as the shape, size, or movement mode is not particularly limited.

The above-mentioned "blocking release position" is a position where the blocking amount of the light entering the reflector from the light source can be made smaller than when the movable shade is at the blocking position, and its specific position is particularly Not limited to
It does not necessarily have to be a position where the shield for the light incident on the reflector from the light source can be completely released.

The above-mentioned "shade driving device" is not particularly limited in its specific constitution as long as it is constructed so as to move the movable shade between the shield position and the shield release position. For example, a solenoid. It is possible to employ a device using a pulse motor, a device using a pulse motor, or the like. The mode of "moving" the movable shade by the shade driving device is not particularly limited, and for example, rotation or linear reciprocating motion can be adopted.

The shape of the "low beam light distribution pattern" is not particularly limited as long as it has a predetermined cutoff line at the upper edge. Further, the above-mentioned "auxiliary light distribution pattern" is not particularly limited in its shape as long as it has a cutoff line above the cutoff line of the low beam light distribution pattern.

[0015]

As described above, the vehicular headlamp according to the present invention has a shield position for shielding a part of the light incident on the reflector from the light source and a shield release position for releasing the shield. A movable shade configured to be adopted,
A shade drive device for moving the movable shade between the shield position and the shield release position is provided, and when the movable shade is in the shield position, beam irradiation is performed with a low beam distribution pattern having a predetermined cutoff line at the upper edge. On the other hand, when the movable shade is at the blocking release position, an auxiliary light distribution pattern having a cutoff line above the cutoff line of the low beam light distribution pattern is added to the low beam light distribution pattern to perform beam irradiation. Therefore, the following operational effects can be obtained.

That is, when the vehicle is in a traveling state where it is difficult to obtain forward visibility by beam irradiation with a low beam distribution pattern, the movable shade is moved to the unblocking position by the shade driving device to move the auxiliary light distribution pattern to the low beam distribution pattern. If it is added to the light pattern, front visibility can be improved. For example, when the vehicle turns in the opposite lane, it is possible to sufficiently illuminate the front in the turning direction, and even when the vehicle goes straight, the road surface in front of the vehicle can be sufficiently covered when going from a downhill to an uphill. It becomes possible to irradiate.

At this time, since the auxiliary light distribution pattern has a cutoff line, even when this auxiliary light distribution pattern is added to the low beam light distribution pattern, the entire light distribution pattern has a cutoff line.
Therefore, it is possible to enhance the forward visibility of the driver of the own vehicle while preventing the oncoming driver from glare.

Moreover, since the beam irradiation is performed by the movable shade in such a light distribution pattern that immediately responds to the running condition of the vehicle, the auxiliary light distribution pattern can be accurately formed by the inexpensive and compact structure. Can be formed.

As described above, according to the present invention, in the vehicle headlamp including the lamp unit for low beam irradiation,
With an inexpensive and compact configuration, it is possible to accurately perform beam irradiation in a light distribution pattern that immediately responds to the traveling condition of the vehicle.

In the above structure, the timing for operating the shade driving device is not particularly limited,
If the movable shade is configured to move to the unblocking position when the vehicle turns to the opposite lane side, the direction of travel of the vehicle in The front can be sufficiently illuminated.

It goes without saying that the state of actually turning to the opposite lane side corresponds to the "when turning to the opposite lane side" here, but at the present time, the vehicle still turns to the opposite lane side. However, when it is clear that the vehicle will make a turn to the opposite lane in the near future (for example, when the turn signal is operating), "when turning to the opposite lane"
May be included in.

As described above, the shape of the cut-off line of the low-beam light distribution pattern is not particularly limited, but this cut-off line is a horizontal cut-off line on the opposite lane side and an oblique rise from the horizontal cut-off line to the own lane side. In the case of a cut-off line, if the cut-off line of the auxiliary light distribution pattern is formed so as to extend substantially parallel to the diagonal cut-off line on the opposite lane side of the diagonal cut-off line of the low-beam light distribution pattern, the vehicle will face the opposite direction. When the vehicle travels toward the lane, it is possible to effectively supplement the visibility in the forward direction of the vehicle while preventing the oncoming driver from glare by additionally forming the auxiliary light distribution pattern.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan sectional view showing a vehicle headlamp according to an embodiment of the present invention.

As shown in the figure, the vehicle headlamp 10 according to the present embodiment is a lamp located on the left side of a pair of left and right four-lamp headlamps provided at the front end of the vehicle. The lamp located on the right side has the same structure.

The vehicular headlamp 10 includes a high beam lamp unit 16 and a low beam lamp unit 18 which are arranged laterally adjacent to each other in a lamp chamber formed by a transparent cover 12 and a lamp body 14 which are transparent. Are provided so as to be tiltable in the vertical and horizontal directions as one tilting unit 20. And this vehicle headlamp 10
The low beam lamp unit 18 is turned on to perform low beam irradiation, and the lamp units 16 and 18 are turned on simultaneously to perform high beam irradiation.

The high beam lamp unit 16 includes a parabolic reflector 22 having an optical axis Ax1 extending in the vehicle front-rear direction, and a halogen bulb 24 having a single filament 24a. Halogen bulb 2
4 is supported by the reflector 22 so that its filament 24a is positioned on the optical axis Ax1. The reflector 22 has a reflecting surface 22a in which a plurality of reflecting elements (not shown) are formed on a paraboloid of revolution whose center axis is the optical axis Ax1, and directs the light from the filament 24a to the front. It is designed to be diffused, deflected and reflected.

On the other hand, the low beam lamp unit 18 is
A parabolic reflector 26 having an optical axis Ax2 extending in the vehicle front-rear direction, a discharge bulb 28 having a discharge light emitting portion 28a (light source), and a movable shade 30 (which will be described later) are provided. The discharge bulb 28 is
The discharge light emitting portion 28a is positioned on the optical axis Ax2 and is supported by the reflector 26 via a valve supporting member 38. The reflector 26 has a reflecting surface 26a in which a plurality of reflecting elements (not shown) are formed on a paraboloid of revolution having the optical axis Ax2 as its central axis, and the light from the discharge light emitting portion 28a is forwarded. It is designed to be diffused and deflected toward.

The reflector 22 of the high beam lamp unit 16 and the reflector 2 of the low beam lamp unit 18
6 is integrally formed via the tilting unit panel 20a, and thereby the tilting unit 20 is configured. The tilting unit 20 is supported at the left and right upper ends thereof by the lamp body 14 via aiming mechanisms 32, 34, and is supported at the central lower end thereof by the lamp body 14 at a leveling mechanism 36. The tilting unit 20 is tilted in the vertical direction by driving the leveling mechanism 36.

FIG. 2 is a detailed view of a main part of FIG. 1 showing the low beam lamp unit 18 in detail, and FIG. 3 is a view of FIG.
FIG. 4 is a sectional view taken along the line III-III, and FIG. 4 is a view in the direction of arrow IV in FIG. 3.

As shown in these figures, the movable shade 3
0 is provided so as to be able to reciprocate in the front-rear direction so as to cover the discharge bulb 28 from the front side in a cup shape, and adopts a shield position shown by a solid line in the figure and a shield release position shown by a two-dot chain line in the figure. I'm supposed to get it. When the movable shade 30 is in the shielding position, the discharge light emitting unit 28a
From the left and right peripheral portions B and C of the reflecting surface 26a of the reflector 26
While the light incident on the reflection surface 26a is shielded and only the light incident on the central portion A of the reflection surface 26a is allowed, the shield is released and the discharge surface 28a is reflected from the reflection surface 2a at the shield release position.
Light is allowed to enter the left and right peripheral portions B and C of 6a.

The movable shade 30 is moved by driving the shade driving device 40. The shade driving device 40 is composed of a solenoid having a built-in return spring, and is fixed to the valve support member 38 below the discharge bulb 28 so that the plunger 40a thereof projects forward. A lower end portion of a stay 30a extending downward from a lower end portion of the movable shade 30 is fixed to a tip end portion of a plunger 40a of the shade driving device 40.

As shown in FIG. 3, the shade driving device 40
Are controlled by the control unit 50.

That is, detection signals from the steering angle sensor 52 and the direction indicator switch 54 are input to the control unit 50, and the steering operation is performed by the input signal from the steering angle sensor 52. The turn signal switch 54 detects the fact that the turn signal has been operated (the turn signal has been activated).

The control unit 50 outputs a drive signal to the shade drive device 40 when a steering operation or a turn signal operation for turning the vehicle to the opposite lane side is performed. Shade drive device 40
When this drive signal is input, the solenoid is excited to move the plunger 40a forward to the position indicated by the chain double-dashed line to move the movable shade 30 to the shielding release position. On the other hand, when the drive signal is no longer input, The solenoid 40 is de-excited and the elastic force of the return spring moves the plunger 40a back to the solid line position to move the movable shade 30 to the closed position.

FIG. 5 shows a vehicle headlamp 1 according to this embodiment.
It is a figure which shows transparently the light distribution pattern formed on the virtual vertical screen arrange | positioned by the beam irradiation from 0 at the position of 25 m ahead of a lamp.

The vehicle headlamp 10 forms a left-beam low-beam light distribution pattern P (L) as shown in FIG. 9A by the beam irradiation from the low-beam lamp unit 18 during low-beam irradiation. On the other hand, during the high beam irradiation, the high beam light distribution pattern P (H) is superimposed on the low beam light distribution pattern P (L) as shown in FIG. The formed light distribution pattern is formed. However, even when the low beam is emitted, when the vehicle turns to the opposite lane side (right side), the auxiliary light distribution indicated by the two-dot chain line in FIG. A light distribution pattern to which the patterns P (B) and P (C) are added is formed.

The low-beam light distribution pattern P (L) is a light distribution pattern formed by light reflected from the central portion A of the reflecting surface 26a of the reflector 26 when the movable shade 30 is in the shielding position. As shown by the solid line in FIG. 5A, the upper edge has a cutoff line consisting of a horizontal cutoff line CL1 and a diagonal cutoff line CL2. The horizontal cutoff line CL1 is formed on the opposite lane side with respect to the front direction of the lamp (HV), while the diagonal cutoff line CL2 rises diagonally from the horizontal cutoff line CL1 to the own lane side (for example, 15 °). Stand up in) is formed.
An intersection point (elbow point) E between the horizontal cutoff line CL1 and the oblique cutoff line CL2 is 0.5 of HV.
It is set at a lower position of -0.6 °. In the low beam light distribution pattern P (L), a hot zone (high light intensity area) HZ is provided in the lower left vicinity area of the elbow point E.
(L) is formed.

FIG. 6 is a perspective view of a main part of a light distribution pattern formed on a virtual vertical screen located 25 m in front of the lamp when the vehicle turns to the opposite lane side (right side) in the low beam irradiation state. FIG.

In this state, auxiliary light distribution patterns P (B) and P (C) are added to the low beam light distribution pattern P (L), but these auxiliary light distribution patterns P (B) and P (C) are added.
Are the left and right peripheral portions B and C of the reflecting surface 26a of the reflector 26 when the movable shade 30 is in the shielding release position.
It is a light distribution pattern additionally formed by reflected light from.

The auxiliary light distribution pattern P (B) formed by the reflected light from the right side (left side in FIG. 4) of the reflecting surface 26a is the horizontal cutoff line CL1.
Further, it is formed along the diagonal cutoff line CL2 above the diagonal cutoff line CL2. The upper edge of the auxiliary light distribution pattern P (B) extends diagonally to the diagonal cutoff line CL2 substantially parallel to the diagonal cutoff line CL2 at a position on the opposite lane side at a predetermined angle (for example, 5 °) with respect to the diagonal cutoff line CL2.
It is formed as Lb.

On the other hand, the auxiliary light distribution pattern P (C) formed by the reflected light from the left side (right side in FIG. 4) of the reflecting surface 26a is cut horizontally below the horizontal cutoff line CL1. Offline CL
1 is formed along the line 1. The upper edge of the auxiliary light distribution pattern P (C) has a horizontal cutoff line CL1.
Is formed as a horizontal cutoff line CLc that extends in the horizontal direction at substantially the same height as, and a new elbow point E ′ is formed by the horizontal cutoff line CLc and the diagonal cutoff line CLb.

The auxiliary light distribution patterns P (B) and P (C) are
It is formed to have a relatively small size, so that the luminous intensity in the vicinity of the elbow point E ′ is sufficiently increased.

As described in detail above, the vehicular headlamp 10 according to this embodiment is provided with the low beam lamp unit 18 thereof.
However, the movable shade 30 is configured so as to be able to have a shield position that shields a part of the light that enters the reflector 26 from the discharge light emitting unit 28a and a shield release position that releases this shield.
And a shade drive device 40 for moving the movable shade 30 between the shield position and the shield release position. When the movable shade 30 is in the shield position,
Beam irradiation is performed with a low beam distribution pattern P (L) having a cutoff line including a horizontal cutoff line CL1 and a diagonal cutoff line CL2 at the upper edge, while the movable shade 30 is at the shielding release position.
The auxiliary light distribution pattern P (B) having the oblique cutoff line CLb above the horizontal cutoff line CL1 and the oblique cutoff line CL2 is added to the low beam light distribution pattern P (L) to perform beam irradiation. Therefore, the following operational effects can be obtained.

That is, when the vehicle turns to the opposite lane side, it is difficult to obtain the visibility in the turning direction forward by beam irradiation with the low beam light distribution pattern P (L), as in the present embodiment. Then, the movable shade 30 is moved to the shielding release position by the shade driving device 40, and the auxiliary light distribution pattern P (B) is changed to the low beam light distribution pattern P (L).
The visibility of the front side in the turning direction can be enhanced by adding to the.

At this time, since the auxiliary light distribution pattern P (B) has the oblique cutoff line CLb, this auxiliary light distribution pattern P (B) is used as the low beam light distribution pattern P (L).
In the case of addition to the above, the entire light distribution pattern has the horizontal cutoff line CL1 and the oblique cutoff line CLb. Therefore, it is possible to improve the forward visibility of the driver of the own vehicle while preventing the oncoming driver from glare.

In addition, in the present embodiment, since the beam irradiation in the light distribution pattern adapted to such a vehicle running condition is performed by using the movable shade 30, the accuracy is reduced by the inexpensive and compact structure. The auxiliary light distribution pattern can be formed well.

In particular, in this embodiment, the cutoff line CLb of the auxiliary light distribution pattern P (B) is closer to the opposite lane than the diagonal cutoff line CL2 of the low beam light distribution pattern P (L).
Since it is formed so as to extend substantially parallel to the auxiliary light distribution pattern P (B) when the vehicle turns to the opposite lane,
With the additional formation, it is possible to effectively prevent the driver of the oncoming vehicle from giving glare and effectively supplement the visibility in the front of the turning direction.

Moreover, in the present embodiment, the auxiliary light distribution pattern P (B) and the auxiliary light distribution pattern P (C) having the horizontal cutoff line CLc extending in the horizontal direction at the same height as the horizontal cutoff line CL1 are provided along with the auxiliary light distribution pattern P (B). ) Is additionally formed, it is possible to further improve the visibility in the front of the turning direction while preventing the oncoming driver from glare when the vehicle turns in the opposite lane. .

Further, in this embodiment, when the steering operation or the turn signal operation for turning the vehicle to the opposite lane side is performed, the auxiliary light distribution patterns P (B), P
Since (C) is added to the low beam light distribution pattern P (L), not only when actually traveling to the opposite lane side, but at the present time, when traveling to the opposite lane side, However, the auxiliary light distribution pattern P (B), when it is clear that the vehicle will turn to the opposite lane in the near future,
P (C) can be added, which makes it possible to perform beam irradiation in a light distribution pattern corresponding to the driver's gazing point under actual vehicle traveling conditions.

In this embodiment, since the high beam light distribution pattern P (H) is superimposed on the low beam light distribution pattern P (L) during high beam irradiation, sufficient front visibility can be ensured. However, even in this high beam irradiation state, the auxiliary light distribution patterns P (B) and P (C) may be additionally formed when the vehicle travels to the opposite lane side. The visibility of the front can be further enhanced. Also, in the high beam irradiation state, the auxiliary light distribution patterns P (B), P
(C) may be additionally formed, and by doing so, front visibility can be further enhanced.

In this embodiment, the auxiliary light distribution pattern P (B), when the vehicle turns to the opposite lane,
Although P (C) is added to the low beam light distribution pattern P (L) to irradiate the beam, the auxiliary light distribution pattern P (B), P (B), is also used under other vehicle traveling conditions.
It is possible to additionally form P (C). For example, when the vehicle is approaching an uphill from a downhill, only the short-distance road surface in front of the vehicle is illuminated by the low beam light distribution pattern P (L).
If (B) and P (C) are added to the low beam light distribution pattern P (L) to perform beam irradiation, it is possible to sufficiently illuminate the road surface ahead of the vehicle and improve front visibility.

By the way, as in the vehicle headlamp 10 according to this embodiment, the reflector 22 of the high beam lamp unit 16 and the reflector 26 of the low beam lamp unit 18 are integrally formed via the tilting unit panel 20a. In this case, it is impossible to change the direction of the low beam lamp unit 18 in order to irradiate the beam with a light distribution pattern that immediately responds to the vehicle running condition.
It is not easy to adopt a configuration in which the direction of the reflector 26 is partially changed. On the other hand, in the present embodiment, since the movable shade 30 is used, it is possible to easily perform beam irradiation in a light distribution pattern that immediately responds to the vehicle traveling situation.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing a vehicle headlamp according to an embodiment of the present invention.

FIG. 2 is a detailed view of a main part of FIG. 1, showing the low beam lamp unit of the vehicle headlamp in detail.

FIG. 3 is a sectional view taken along line III-III of FIG.

FIG. 4 is a view on arrow IV in FIG.

FIG. 5 is a perspective view showing a light distribution pattern formed on a virtual vertical screen arranged at a position 25 m in front of the lamp by the beam irradiation from the vehicle headlamp.

FIG. 6 is a diagram showing perspectively a main part of a light distribution pattern formed on the virtual vertical screen when the vehicle turns to the opposite lane side (right side) in the low beam irradiation state.

[Explanation of symbols]

10 Vehicle headlights 12 transparent cover 14 lamp body 16 High beam lamp unit 18 Low beam lamp unit 20 Tilt unit 22,26 reflector 22a reflective surface 24 Halogen bulb 24a filament 28 discharge bulb 28a Discharge light emitting part (light source) 30 movable shades 30a stay 32, 34 Aiming mechanism 36 Leveling mechanism 38 Valve support member 40 Shade drive 40a plunger 50 control unit 52 Rudder angle sensor 54 Direction Indicator Switch A central part Ax1, Ax2 optical axis B right edge C left edge CL1, CLb Horizontal cut-off line CL2, CLc Diagonal cut-off line E, E'Elbow point HZ (L) hot zone P (B), P (C) auxiliary light distribution pattern P (H) High beam light distribution pattern P (L) Light distribution pattern for low beam

Claims (3)

[Claims] 1. A vehicle configured to irradiate a beam in a low beam distribution pattern having a predetermined cut-off line at an upper edge by a lamp unit including a light source and a reflector that reflects light from the light source forward. In a headlight for use, a movable shade configured so as to have a shield position for shielding a part of the light incident on the reflector from the light source and a shield release position for releasing the shield, and the movable shade as described above. A shade driving device that moves between a shield position and a shield release position is provided, and when the movable shade is at the shield position, beam irradiation is performed in the low beam light distribution pattern while the movable shade is at the shield release position. The cut-off line above the cut-off line of the low beam distribution pattern above. Auxiliary light distribution pattern is configured to perform beam irradiation in addition to the low beam distribution pattern, the vehicle headlamp, characterized in that it comprises a. 2. The shade drive device is configured to move the movable shade to the shielding release position when the vehicle turns to the opposite lane side. Vehicle headlights. 3. The cut-off line of the low-beam light distribution pattern comprises a horizontal cut-off line on the side of an oncoming lane and an oblique cut-off line rising obliquely to the own lane side from the horizontal cut-off line. 3. The vehicle headlamp according to claim 1, wherein the vehicle headlight is formed so as to extend substantially parallel to the diagonal cutoff line on the opposite lane side of the diagonal cutoff line of the low beam light distribution pattern. .