JP6745620B2 - Headlamps for motorcycles - Google Patents

Description

The present invention relates to a headlamp for a two-wheeled vehicle, and more particularly to a headlamp that enables control of light distribution during bank traveling, in which the two-wheeled vehicle travels in a tilted state, to a light distribution suitable for safe traveling.

Since two-wheeled vehicles perform so-called bank traveling, in which the vehicle body leans toward the inside of a curve when cornering, so when such a bank occurs during low beam light distribution, the light distribution pattern of the headlamps changes on the road surface and the light irradiation at the cornering destination is changed. It tends to be insufficient. For example, if the two-wheeled vehicle leans to the left while traveling on the left curve, the light distribution pattern will also be tilted to the left along with this, and the illumination of the far-front left area, which is the destination of the two-wheeled vehicle traveling on a curve, becomes insufficient. Therefore, there is a problem in safe driving.

Therefore, the light distribution during cornering traveling is adjusted according to the inclination angle of the vehicle body of the two-wheeled vehicle, that is, the bank angle, and the light distribution of the entire headlamp is compensated. For example, in Patent Document 1, a light source of a headlamp is configured as a unit in which a plurality of LEDs (light emitting diodes) are arranged, the unit is divided into five regions, and the LEDs are turned on in units of these regions. ing. When the bank angle is 0, the LED in the central region is turned on, and when the bank angle is increased leftward or rightward, the LED in the corresponding region is turned on to compensate the light distribution.

The technique of Patent Document 2 also includes a plurality of LEDs for illuminating different areas, and the light distribution is compensated by controlling the turning on and off of these LEDs.

JP, 2006-131212, A Japanese Patent No. 4864562

The technique of Patent Document 1 controls the lighting and extinguishing of LEDs on an area-by-area basis, following changes in the bank angle. Therefore, the light distribution control of the headlamp is based on the region unit, and it is difficult to perform high-definition light distribution control corresponding to a minute change in the bank angle. That is, a structure is adopted in which the region to be turned on is switched when the change in the bank angle exceeds a predetermined threshold value, but the light distribution is not changed until the change in the bank angle exceeds the threshold value, and the threshold is changed. When the value exceeds the value, the light distribution is changed in units of areas, so the change in the brightness of the light distribution and the change in the illumination area are significant, which causes discomfort for the driver of the own vehicle and the occupants of oncoming vehicles. Will end up. In Patent Document 2 as well, the control for turning on and off in LED units has the same problem.

An object of the present invention is to provide a motorcycle headlamp that enables highly accurate light distribution control during banking.

A motorcycle headlamp according to the present invention includes a lamp unit including a light source device in which a plurality of light emitting elements are arranged in a matrix, and a lighting control device that controls a lighting state of the light source device by following a change in a bank angle of a vehicle. The lighting control device is characterized in that it follows the change in the bank angle and independently controls the light amounts of the plurality of light emitting elements.

In the present invention, the control of the light amount in the lighting control device is a control including a light-off state in which the light amount is 0, a first lighting state in which the light amount is a predetermined light amount, and a second lighting state in which the light amount is lower than the predetermined light amount. Further, in the present invention, the lighting control device defines a lighting region when a part of the plurality of light emitting elements is controlled to be in the first lighting state and the other is in a non-lighting state so that the boundaries are inclined with respect to the matrix direction. It is preferable to control the light emitting element located at the boundary of the extinguished region to the second lighting state.

According to the present invention, it is possible to realize highly accurate light distribution control in which the light distribution changes in units of minute areas by independently controlling the light amounts of the plurality of light emitting elements by following the changes in the bank angle. Further, by independently controlling the light amount of the light emitting element located in the light-dark boundary area of the light distribution, it is possible to realize the light distribution control with higher accuracy.

The schematic front view of a part of motorcycle which applied the headlamp of the present invention. (A) is a longitudinal cross-sectional view of the headlamp, (b) is a front view of the light source device. (A) is a block circuit diagram of a lighting control device and a light source device, (b) is a figure which shows the relationship between a control signal and the amount of lighting light. 3A and 3B are diagrams for explaining high beam light distribution, FIG. 7A is a front view showing a lighting state of a light source device, and FIG. 4A and 4B are diagrams illustrating low-beam light distribution, FIG. 7A is a front view showing a lighting state of a light source device, and FIG. It is a figure explaining light distribution when a bank angle is small, (a) is a front view showing a lighting state of a light source device, (b) is a mimetic diagram of light distribution. 6A and 6B are diagrams illustrating light distribution when the bank angle is large, FIG. 7A is a front view showing a lighting state of a light source device, and FIG. FIG. 3 is a diagram for explaining the unevenness of the cut-off line. (a1) and (a2) are a part showing the lighting state of the light source device when the light amount control is not performed and (b1) and (b2) are the light source device lighting states. Front view and its light distribution diagram.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a schematic structure in which the present invention is applied to a headlamp HL of a motorcycle (motorcycle), and a headlamp HL is provided on a cowl C provided at a front portion of a motorcycle B. As shown in the sectional view taken along the line II-II of FIG. 1, the headlamp HL has a container-shaped lamp body 11 having an opening at the front and an opening of the lamp body 11. It has a lamp housing 1 composed of a translucent front cover 12 to be worn, and a projection type lamp unit 2 and a bank when the motorcycle (own vehicle) B is tilted left and right in the lamp housing 1. A bank angle sensor 3 for detecting an angle is incorporated.

The bank angle sensor 3 is composed of a gyro sensor or an acceleration sensor and detects a tilt angle of the motorcycle B in the left-right direction. Here, the bank angle when the motorcycle B is in the vertical state is 0°, and the bank angle Bθr inclined to the right and the bank angle Bθl inclined to the left are detected with reference to this.

The lamp unit 2 includes a base substrate 21 supported by the lamp body 11, and a projection lens 22 supported by the base substrate 21 via a lens holder 23. A light source device 4 and a lighting control device 5, which will be described in detail later, are integrally formed on the base substrate 21. The projection lens 22 projects the light emitted from the light source device 4 forward, and illuminates the front region of the host vehicle with a required light distribution. The bank angle sensor 3 may be mounted on the base substrate 21.

As shown in the front view of FIG. 2A, the light source device 4 has a plurality of LEDs 40 mounted on the front surface of a light source substrate 41 fixedly supported on the front surface of the base substrate 21. These LEDs 40 are composed of chip-type white LEDs having a minute-sized rectangular light emitting surface, and the light emitting surface is directed toward the surface direction of the light source substrate 41, that is, in the direction parallel to the optical axis Lx of the lamp unit 2. Is directed. These LEDs 40 are arranged in a matrix at a required pitch dimension within a generally oblong elliptical region having a horizontal axis H as a long axis when viewed from the front of the lamp unit 2. The center position O of this horizontally long elliptical region is set to a position slightly offset from the optical axis of the lamp unit. The LEDs 40 of the light source device 4 are actually arranged in a matrix of about 50 rows in the vertical direction and about 60 columns in the horizontal direction, but the illustration is simplified here.

The optical axis of the projection lens 22 is aligned with the optical axis Lx of the lamp unit, and the focus of the projection lens 22 on the rear side of the lamp unit is arranged close to the surface of the light source substrate 41, that is, the light emitting surface of the LED 40. Therefore, when the LED 40 is turned on, the light emitted from the LED 40 is projected toward the front of the host vehicle, and the front region thereof is illuminated with a required light distribution.

FIG. 3A is a block circuit diagram of the light source device 4 and the lighting control device 5. The lighting control device 5 uses a vehicle-mounted battery BAT as a power supply and outputs a predetermined power, and a power supply unit 51. A control unit 52 that controls the lighting of the LED 40 of the light source device 4 with the output power of 51 is provided.

The power supply unit 51 is composed of, for example, a DC-DC converter, inputs the power of the vehicle-mounted battery BAY, and outputs the output power Vo for turning on the LEDs 40 of the light source device 4 to the output line. A lamp lighting switch LSW operated by a driver is connected to the power supply unit 51, and when the lamp lighting switch LSW is turned on, the output power Vo is output to the output line.

A light distribution changeover switch (dimmer switch) DSW that is operated by a driver to switch between a high beam and a low beam and the bank angle sensor 3 are connected to the control unit 52. The control unit 52 determines a suitable light distribution based on the switching state of the light distribution changeover switch DSW and the detection output of the bank angle sensor 3, and the plurality of LEDs 40 of the light source device 4 are determined based on the determined light distribution. A control signal Sc for turning on all or some of the selected LEDs 40 is output to the light source device 4.

In the light source device 4, a plurality of LEDs 40 each have a current control element, here a transistor TR, interposed between the LED 40 and an output line of a power supply unit 51, and the control unit 52 controls the base of each transistor TR. The signal Sc is input as the base current. As a result, the control signal Sc that is input to each transistor TR is rendered conductive, and a current associated with the output power Vo of the output line flows through the connected LED 40, and the LED 40 is turned on.

In addition, the control unit 52 can control the signal level of the control signal Sc, that is, the level of the base current of the transistor TR to change and control the current flowing through the LED 40 and control the light amount when the LED 40 is turned on. It is said that. For example, here, the control unit 52 is set to pass a current of level a, level b, or level c as the control signal Sc, and the LED 40 is turned off at the level a. Further, at level c, a first lighting state in which a predetermined amount of light is turned on is set, and at level b, a second lighting state in which a light amount is lower than the predetermined amount of light is set.

According to the headlamp HL configured as described above, when the driver turns on the lamp lighting switch LSW, the lighting control device 5 outputs a predetermined power Vo to the output line in the power supply unit 51. At this time, when the light distribution changeover switch DSW is switched to the high beam, the control unit 52 executes control to turn on all the LEDs 40 of the light source device 4 at the level c.

That is, the control unit 52 outputs a control signal of level c to each transistor TR of all LEDs 40. As a result, all the LEDs 40 are turned on with a predetermined amount of light and brought into the first lighting state, as shown in FIG. 4A by the black rectangles indicating the LEDs 40 turned on when the light source device 4 is viewed from the front. .. The light emitted from each LED 40 becomes a combined light flux, which is projected onto the front area by the projection lens 22, and the lamp unit 2 irradiates the light with high beam distribution. FIG. 4B is a light distribution diagram of the high beam light distribution PHi formed by this lighting when the front side of the motorcycle B is viewed from the rear side. Here, since the projection lens 22 vertically and horizontally reverses and projects the light emitted from each LED 40, the light distribution of FIG. 4B is obtained by vertically and horizontally inverting the lighting region of FIG. 4A. Become.

When the light distribution changeover switch DSW is switched to the low beam while the lamp lighting switch LSW is turned on, the control unit 52 executes control for lighting some LEDs 40 selected by the light source device 4. That is, as shown in FIG. 5A, when the light source device 4 is viewed from the front, a control signal of level c is output to the LED 40a (black-painted LED) in the upper region of the horizontal line H passing through the lamp unit optical axis Lx. , The first lighting state. A control signal of level a is output to the other LEDs 40b (white LEDs) to turn them off.

Thereby, the light distribution irradiated to the front region by the projection lens 22 is below the cutoff line CL along the horizontal line H passing through the lamp unit optical axis Lx as shown in the light distribution diagram of FIG. 5B. It becomes a low beam light distribution PLo that illuminates the area. In this case, although illustration is omitted, in the front area on the left side of the lamp unit optical axis Lx, the light irradiation range may be expanded to the upper side to provide cut-off light distribution.

When the motorcycle B tilts in the left-right direction on a curved road or the like while traveling in the low-beam light distribution PLo and a bank angle occurs, that is, when the bank angle becomes larger than 0°, the control unit 52 causes the bank angle sensor 3 to operate. The light source device 4 is controlled based on the detection output. For example, as shown in FIG. 6B, when the two-wheeled vehicle B is banked to the left by the bank angle Bθl1, the low-beam light distribution has a cutoff line to the left that is equal to the bank angle Bθl1 as shown by the chain line in the figure. Inclination to the left by θ1 results in insufficient illumination of the left region in the front and the distance.

As shown in FIG. 6A, the control unit 52, when viewed from the front of the light source device 4, passes through the lamp unit optical axis Lx and is inclined to the horizontal line H at an imaginary horizontal line H1, which is a bank angle Bθl1. The control signal Sc of the level c is output to the LEDs 40a in the upper region of the virtual horizontal line H1 inclined by the equal angle θ1 to set the first lighting state. The control signal Sc of the level a is output to the LED 40b in the area below the virtual horizontal line H1 to turn off the LED 40b.

As a result, the light flux from the light source device 4 emitted toward the front region by the projection lens 22 is inclined to the left by an angle θ1 equal to the bank angle Bθl1 with respect to the horizontal line H passing through the lamp unit optical axis Lx. It becomes a luminous flux. Therefore, as shown in the light distribution diagram of FIG. 6B, the front region irradiated with this light flux is corrected so that the cut-off line CL is directed along the horizontal line H regardless of the bank state of the motorcycle B. The light is emitted by the bank compensation light distribution PB1 thus generated.

As shown in FIG. 7B, when the bank angle of the motorcycle B further increases and becomes bank angle Bθl2 (>Bθl1), the control unit 52 controls the light source device 4 based on the increased bank angle Bθl2. In this case, as shown in FIG. 7A, the inclination angle of the virtual horizontal line H2 when the light source device 4 is viewed from the front is increased to an angle θ2 equal to the bank angle Bθl2, which is larger than the virtual horizontal line H2. A control signal of level c is output to the LED 40a in the upper region to bring about the first lighting state. A control signal of level a is output to the LED 40b in the area below the virtual horizontal line H2 to turn off the LED 40b.

As a result, the light beam emitted forward by the projection lens 22 becomes a light beam inclined to the left by an angle θ2 equal to the bank angle Bθl2 with respect to the horizontal line H passing through the optical axis Lx of the lamp unit. Therefore, as shown in the light distribution diagram of FIG. 7B, the front region irradiated with this light flux is modified so that the cutoff line CL is directed along the horizontal line H regardless of the increase of the bank angle. The light is emitted by the bank compensation light distribution PB2.

In this way, when controlling the light source device 4, the lighting control device 5 sets a virtual horizontal line corresponding to the bank angle detected by the bank angle sensor 3, and the LED 40 that lights up with this virtual horizontal line as a reference. Select. Therefore, when the bank angle is finely changed, the inclination angle of the virtual horizontal line is also finely changed, but the lighting control of the LED 40 based on the virtual horizontal line is a control for each LED 40. .. Accordingly, in the light distribution control according to the change of the bank angle, it is possible to control the LEDs 40 in units of one unit, and it is possible to realize the light distribution control by the fine cut-off line control, in other words, the light distribution control with high accuracy. ..

Here, when the light emission of the LED is controlled with reference to the virtual horizontal line in the light source device, the virtual horizontal line Hx is an oblique direction with respect to the arrangement direction (matrix direction) of the LEDs 40, as shown in FIG. 8(a1). Therefore, the LED 40c may be located on the virtual horizontal line Hx. In this case, when the LED 40c is turned on at the level c and brought into the first lighting state, the lighting region deviates from the cutoff line CL and becomes brighter, and the cutoff line CL becomes uneven as shown in FIG. 8(a2). Sometimes. On the other hand, when the LED 40c is turned off at the level a, a dark region in which the extinguished portion recedes from the cutoff line CL is generated, and the LED 40c may be uneven.

In such a case, the control unit 52 causes the light source device 4 to turn on the LED 40c on the virtual horizontal line Hx at the level b as shown in FIG. That is, when a part 40a of the LED 40 is controlled to the first lighting state and another LED 40b is controlled to the non-lighting state, the LED 40c located at the boundary between the lighting region and the non-lighting region is controlled to the second lighting state. The LED 40c in the second lighting state, which is lit at the level b, is displayed in a stippled manner.

Since the light quantity of the LED 40c in the second lighting state of the level b is lower than the light quantity of the first lighting state of the level c as shown in FIG. 3B, as shown in FIG. 8B2. The state in which this portion deviates from the cutoff line CL and becomes brighter or retracts and becomes darker is suppressed. Therefore, the cut-off line CL is prevented from becoming uneven, and the quality of light distribution is improved.

The second lighting state of the LED at the level b is, for example, a so-called diagonal cut in which the left side region of the cutoff line CL of the low beam distribution PLo shown in FIG. 5B is set diagonally above the horizontal line. It may be applied to light distribution having an off-line. That is, by turning on the LED positioned on the diagonal cutoff line at the level b, it is possible to avoid the diagonal cutoff line from becoming uneven, and a suitable low beam light distribution can be obtained.

In the embodiment, the case where the two-wheeled vehicle has the bank angle inclined to the left has been described, but the same applies to the case where the two-wheeled vehicle has the bank angle inclined to the right, and the LED of the light source device is symmetrical with respect to the example described in the embodiment. Proper light distribution can be obtained by performing lighting control.

Further, the plurality of LEDs configuring the light source device are not limited to the number and arrangement of the embodiments, and may be, for example, a radial arrangement around the optical axis of the lamp unit or a concentric arrangement. .. The larger the number of LEDs, the smaller the area of the light distribution region that each LED is in charge of, so that the light distribution control according to the bank angle change can be realized with higher accuracy.

Here, the control signal Sc in the control unit 52 is not limited to the levels a, b, and c of the embodiment, and the light amount control may be performed at a number of levels higher than this. Alternatively, the level of the control signal may be continuously changed to perform linear light amount control.

In this embodiment, since the light source device 4 and the lighting control device 5 are mounted on the single base substrate 21, when the light source device 4 is mounted on the lamp unit 2, the lighting control device 5 can also be mounted on the lamp unit 2. become. Thereby, the configurations of the lamp unit 2, the light source device 4, and the lighting control device 5 can be simplified, and the assembling work into the lamp housing 1 becomes easy. Further, by mounting the bank angle sensor 3 inside the lamp housing 1, it is possible to execute light distribution control corresponding to the bank angle by the headlamp HL alone, and enhance the versatility as a headlamp for a motorcycle. it can.

In the embodiment, the light source device is composed of a plurality of LEDs, but the required light emitting surface is formed as a plurality of light emitting areas, and a light emitting body capable of independently controlling the light amount of each light emitting area, for example, It may be configured by an organic EL (electroluminescence). In this case, the present invention can be realized by replacing the light emitting element of the present invention with each light emitting region of the EL.

1 Lamp Housing 2 Lamp Unit 3 Bank Angle Sensor 4 Light Source Device 5 Lighting Control Device 21 Base Board 22 Projection Lens 40 LED (Light Emitting Element)
40a LED in the first lighting state
40b LED off
40c LED in second lighting state
41 light source board 51 light source section 52 control section B motorcycle (vehicle)
HL headlamp BAT vehicle battery LSW lamp lighting switch DSW light distribution switch TR transistor (current control element)

Claims (3)

A headlamp for a motorcycle, comprising: a lamp unit including a light source device in which a plurality of light emitting elements are arranged in a matrix; and a lighting control device that controls a lighting state of the light source device in accordance with a change in a bank angle of a vehicle, The lighting control device follows the change of the bank angle and puts the plurality of light-emitting elements into an extinguished state in which the light amount is 0, a first lighting state in which the light amount is a predetermined light amount, and a second lighting state in which the light amount is lower than the predetermined light amount. When a part of the plurality of light-emitting elements is controlled to a first lighting state and the other is controlled to a non-lighting state so that the boundary is inclined with respect to the matrix direction, the lighting region and the non-lighting region are controlled. A headlamp for a motorcycle, wherein a light emitting element located at a boundary is controlled to a second lighting state . The motorcycle headlamp according to claim 1 , wherein the light source device and the lighting control device of the lamp unit are mounted on a single substrate. The headlamp for a motorcycle according to claim 2 , further comprising a bank angle sensor that detects the bank angle, the bank angle sensor, the lamp unit, and the lighting control device being housed in the same lamp housing.

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