Bicycle lighting device

Abstract

To provide a lighting device for bicycle which includes a lamp unit having a function for drawing a prescribed design on a road surface on the left front side and / or the right front side on the lateral side relative to a driver of a bicycle for safety improvement of the bicycle.SOLUTION: A lighting device 10 for bicycle illuminates a front surface in the travel direction with a central light-emitting unit provided in a central region when viewed from the front surface in the same housing, and comprises: a right light-emitting unit 12R and a left light-emitting unit 12L on both sides; and a control board 17. At least one of the right light-emitting unit 12R and the left light-emitting unit 12L includes a drawing optical system including an LED light source and an image formation unit. The central light-emitting unit emits a light distribution pattern with a narrow breadth conforming to a standard specification as a headlight. The drawing optical system draws a prescribed image toward a road surface on the lateral side relative to the light distribution pattern of the central light-emitting unit.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a bicycle lighting device, and more particularly to a bicycle lighting device having a light-emitting part for illuminating the center of the front in the traveling direction as viewed from above, and a light-emitting part for drawing a predetermined design toward the left and right road surfaces near the bicycle, and particularly to a headlamp for a bicycle.

Background Art

[0002] In conventional bicycle headlamps, it was common for there to be only one light-emitting part that used an incandescent light source to irradiate light in the illumination direction (for example, see Patent Document 1). In addition, lighting devices having a light source that lights up when turning left or right have also been proposed in order to improve safety (for example, see Patent Document 2).

[0003] The bicycle lighting unit of Patent Document 1 includes an illuminance detection unit for detecting the ambient brightness inside the main body case, and a light-emitting body composed of a reflector and a small incandescent bulb, and controls the lighting and extinguishing of the small incandescent bulb based on the illuminance detected by the illuminance sensor.

[0004] The bicycle lighting unit of Patent Document 2 includes a lighting unit composed of a central lamp, a left-facing lamp for illuminating the left front, and a right-facing lamp for illuminating the right front, a rotation detection unit for detecting rotation around a predetermined axis, and a lamp drive unit for controlling the lighting state of the left-facing lamp and the right-facing lamp based on the detection signal of the rotation detection unit. The lighting unit is mounted on the bicycle so that the central lamp irradiates the front directly in front of the front wheel that is operated by the handle.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] The bicycle lighting device described in Patent Document 1 can illuminate the area directly in front of the rider, but it cannot illuminate the area to the left front or right front.

[0007] The bicycle lighting unit described in Patent Document 2 can selectively illuminate the left front or right front in addition to the direction directly in front of travel, depending on the detection signal from the rotation detection unit. However, it only describes keeping the central lamp constantly lit and changing its illuminance according to the steering angle of the handlebars, as well as illuminating the left-facing lamp or the right-facing lamp, and does not provide any specific description of the light distribution of the left-facing lamp or the right-facing lamp.

[0008] Furthermore, the bicycle lighting devices described in Patent Documents 1 and 2 describe ways to improve visibility in front of the vehicle for the cyclist, but they do not describe in any way how they can send a message to pedestrians or other drivers of other vehicles such as bicycles when viewed from the perspective of those drivers.

[0009] This invention was proposed in view of the above conventional circumstances, and its main objective is to realize a bicycle lighting device that has a lamp unit that has the function of drawing a predetermined design on the road surface to the left front and / or right front, to the side of the cyclist, in order to improve the safety of bicycles. [Means for solving the problem]

[0010] One aspect of the present invention provides the following bicycle lighting devices [1] to [5] and the bicycle [6] in order to achieve the above objectives.

[0011] [1] A central light-emitting unit located in the central region when viewed from the front and formed to emit light toward the front, A right light-emitting unit is provided, which is shifted to the right of the center line of the central light-emitting unit when viewed from the center line of the central light-emitting unit, and is formed to emit light in a direction that is to the right, forward, and in front of the central light-emitting unit; A left light-emitting unit is provided, which is shifted to the left of the center line of the central light-emitting unit when viewed from the center line of the central light-emitting unit, and is formed to emit light in a direction that is to the left, forward, and in front of the central light-emitting unit; A control board equipped with a lighting drive circuit that controls the lighting state of the central light-emitting unit, the right light-emitting unit, and the left light-emitting unit, The housing comprises a light chamber that houses the central light-emitting unit, the right light-emitting unit, the left light-emitting unit, and the control board, The housing has a fixing part formed therein for fixing it to a bicycle. At least one of the light-emitting units, the right light-emitting unit and the left light-emitting unit, is provided with a drawing optical system consisting of an LED light source and an image forming unit provided in front of the direction of illumination of the LED light source. The drawing optical system is a bicycle lighting device that emits light to draw a predetermined image toward the road surface in front of the central light-emitting unit, according to the light distribution pattern of the central light-emitting unit.

[0012] [2] The image forming section of at least one of the light-emitting units, the right light-emitting unit and the left light-emitting unit, has an image film fixing frame attached to the light-emitting unit. of The bicycle lighting device according to [1], characterized in that it includes an image film that can be inserted into and removed from the image film fixing frame. [3] The bicycle lighting device according to [1], characterized in that the image forming section of at least one of the right light-emitting unit and the left light-emitting unit is a variable type image forming section whose design can be changed by electrical means. [4] The control board is The system comprises a first control unit that controls the illumination state of the light source of the central light-emitting unit, and a second control unit that controls the illumination state of the respective light sources of the right light-emitting unit and the left light-emitting unit. The first control unit performs continuous lighting in response to the output signal of the illuminance sensor or in response to the switch operation. The second control unit performs flashing illumination independently of the illumination of the light source of the central light-emitting unit by the first control unit, as described in any one of the bicycle lighting devices described in [1] to [3]. [5] The bicycle lighting device according to any one of [1] to [4], characterized in that the light sources of the central light-emitting unit, the right light-emitting unit, and the left light-emitting unit are LEDs. [6] A bicycle equipped with a bicycle lighting device as described in any of [1] through [5] above. [Effects of the Invention]

[0013] According to the present invention, a bicycle lighting device has the function of illuminating the road surface directly in front of the bicycle's direction of travel, as well as drawing a predetermined design on the road surface to the left front and / or right front. This widens the illuminated area of ​​the road surface, making it easier for the rider to see their feet and use the device. Furthermore, the presence of the bicycle can be made known not only to the rider but also to people, cars, other cyclists, and others in the vicinity through the road surface drawing. These features enhance the safety of cycling.

[0014] Furthermore, according to the invention described in [2] or [3] above, the predetermined image drawn on the road surface can be changed by the drawing optical system, so that various impressions can be given depending on the driver and / or those around them. Furthermore, according to the invention described in [4] above, the recognition of the predetermined image drawn on the road surface can be improved. Furthermore, according to the invention described in [5] above, since all the light sources of the central light-emitting unit, the right light-emitting unit and the left light-emitting unit are LEDs, the control circuits can be made common and simplified. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a schematic side view showing a vehicle (bicycle) equipped with a bicycle lighting device according to one embodiment of the present invention. [Figure 2]FIG. 2 is a schematic perspective view observed from the obliquely upward front direction of a bicycle showing the bicycle lighting device of the present embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view showing a horizontal cross-section of the bicycle lighting device of the present embodiment. [Figure 4] FIG. 4 is a vertical cross-sectional view for explaining the optical system of the center light-emitting unit of the present embodiment. [Figure 5] FIG. 5 is a schematic longitudinal cross-sectional view for explaining the left light-emitting unit. [Figure 6] FIG. 6 is a block diagram for explaining the lighting control of the bicycle lighting device. [Figure 7] FIG. 7 is a schematic view shown by an isometric illuminance curve showing the road surface irradiation pattern of the bicycle lighting device. [Figure 8] FIG. 8 is an explanatory view of a design exemplifying a specific example of the road surface drawing pattern in the road surface irradiation pattern shown by a dotted line in FIG. 7. [Figure 9] FIG. 9 is a schematic view showing the bicycle lighting device of the second embodiment. [Figure 10] FIG. 10 is a schematic plan view for explaining the road surface irradiation pattern irradiated by the bicycle lighting device.

Mode for Carrying Out the Invention

[0016] Hereinafter, preferred embodiments of the vehicle lamp according to the present invention will be described with reference to the drawings. In the following description, the descriptions of "front", "rear", "left", "right", "up", and "down" refer to the directions as seen from the driver when installed in a vehicle (bicycle). Therefore, "front" corresponds to the front of the vehicle (the traveling direction of the bicycle), which is the main irradiation direction of the light from the headlamp, "rear" corresponds to the rear side of the vehicle (the back direction of the driver), and "left" corresponds to the left side when based on the traveling direction of the vehicle. "Down" corresponds to the road surface side (the foot side of the driver).

[0017] 〔First Embodiment〕 Figure 1 is a schematic side view showing a vehicle (bicycle) equipped with a bicycle lighting device according to one embodiment of the present invention. The bicycle 1 is composed of a frame 2, a front tire 3, a rear tire 4, handlebars 5, a saddle 6, and pedals 7. The front tire 3 rotates in conjunction with the steering of the handlebars 5, and the headlight 11 is fixed to rotate in conjunction with the front tire 3. A taillight (not shown) is provided on the rear tire 4 or the frame 2.

[0018] The headlight 11 and taillight are types of bicycle lighting devices. The headlight 11 is a lighting device that emits white light directed forward at night or in poor visibility conditions, allowing the rider to see obstacles on the road surface. The taillight is a lighting device that emits red light at night or in poor visibility conditions, indicating the presence of the bicycle 1 from behind.

[0019] Figure 2 is a schematic perspective view of the bicycle lighting device 10 of this embodiment, observed from the front and slightly above the bicycle. Figure 3 is a schematic perspective view showing a horizontal cross-section of the bicycle lighting device 10 of this embodiment. In this embodiment, the bicycle lighting device 10 houses a lamp unit that functions as a headlight 11 to illuminate the area in front of the bicycle. It also houses a drawing lamp unit that projects a predetermined design onto the road surface in front of the bicycle. Specifically, the central light-emitting unit 11, located in the central region when viewed from the front, corresponds to the headlight 11 and is formed to emit light toward the front of the bicycle. Furthermore, drawing lamp units 12, consisting of a pair of lamp units, are arranged on both sides of the central light-emitting unit. The left light-emitting unit 12L is located at a position shifted to the left of the center line M of the central light-emitting unit 11 when viewed from above, and is formed to emit light toward the left front of the central light-emitting unit 11. The right light-emitting unit 12R is located to the right of the center line M of the central light-emitting unit 11 when viewed from above, and is formed to emit light in a direction that is to the right, forward, and in front of the central light-emitting unit 11.

[0020] The central light-emitting unit 11 and the drawing lamp unit 12 are fixed inside the housing 13. The housing 13 is a roughly box-shaped case having a light chamber 14 with an opening at the front. An outer lens 15 made of light-transmitting resin is attached to the front opening, and transmits light emitted from the central light-emitting unit 11 and the drawing lamp unit 12 located inside the light chamber 14 to the outside.

[0021] (Outer lens) The outer lens 15 is described as being transparent, but it may also be equipped with a refractive lens that refracts the light emitted from each lamp unit. A fixing part 13C for fixing to a bicycle is formed on the bottom surface of the housing 13. The fixing part 13C is attached to the mudguard of the front tire 3 using a fixing means such as a screw so that it rotates in conjunction with the front tire 3 of the bicycle. In this embodiment, as shown in Figure 2, the elliptical window part 15C formed at the position corresponding to the central light-emitting unit 11 in a front view, and the circular window parts 15R and 15L corresponding to the drawing lamp units 12 (right light-emitting unit 12R and left light-emitting unit 12L) are formed of a light-transmitting resin material, while the other parts are made of a colored resin material to make it difficult to see inside the lamp chamber 14.

[0022] (housing) The housing 13 consists of a lower housing 14a with a recessed area on the upper side of the bottom that serves as a lamp chamber 14, and an upper housing 14b that covers this recessed area. Inside the recessed area, a lamp unit mounting section is provided on the front side for fixing the central light-emitting unit 11 and the drawing lamp unit 12, and a control device mounting section is provided on the rear side for fixing the battery 16 and the control board 17. As shown in Figure 3, the control board 17 is inserted into the lower housing 14a from above with its thickness direction parallel to the vertical direction, so that it is positioned between the battery 16 and the central light-emitting unit 11 and the drawing lamp unit 12. The outer lens 15, battery 16, central light-emitting unit 11, and drawing lamp unit 12 are also formed so that they can be inserted into the lower housing 14a from above, and are designed so that assembly can be fixed by mounting only from above. This simplifies the assembly process.

[0023] (Central light-emitting unit) The central light-emitting unit 11 illuminates in the range of the illumination angle IC as shown in Figure 3, with the central axis M as the center, in order to form a light distribution pattern that satisfies the light distribution standards for bicycle headlights. The light distribution standards for bicycle headlights are defined in JIS standard number JISC9502 "Bicycle Lighting Devices". It is required that a predetermined illuminance value be obtained at a predetermined measurement position measured on a vertical screen 10m in front of the headlight, and that it conforms to the light distribution characteristics of a) passing light distribution or c) general-purpose light distribution, or both a) passing light distribution and b) riding light distribution. The designated measurement positions are, for example, in the revised version dated March 22, 2021, for c) general-purpose light distribution characteristics, the HV position (the intersection of the HH line, which represents a horizontal plane parallel to the ground, and the VV line, which represents a vertical plane passing through the bicycle), A1 and A2 positions (points on the HH line, 4° to the left and 4° to the right of the VV line), and A3 (a point on the VV line, 3.5° below the HH line). Thus, the light distribution pattern of a bicycle headlight has a main light distribution range of 4° to the left and 4° to the right of the VV line, and although it has the ability to illuminate up to 10m away, it tends to have a light distribution characteristic with a narrow spread in the left and right direction.

[0024] Figure 4 is a vertical cross-sectional view illustrating the optical system of the central light-emitting unit 11 of this embodiment. In this embodiment, as shown in Figure 4, the central light-emitting unit 11 includes an LED light source 11a, a thermally conductive substrate 11b on which the LED light source 11a is mounted, and a reflector 11c that reflects the first light L1 emitted from the LED light source 11a in a forward direction. The reflector 11c has a plurality of reflective surfaces 11c1 formed on it so that the light emitted from the LED light source 11a forms a light distribution pattern that satisfies the light distribution standards for bicycle headlights. The reflective surfaces 11c1 include a paraboloid of revolution with the LED light source 11a as the focal point, and the other reflective surfaces are parabolic reflective surfaces that approximate this reflective surface, and the first light L1 reflects light that contains many parallel rays. The LED light source 11a consists of a chip LED (surface mount LED package) that emits white light as the first light L1. The chip LED is also arranged on the surface of the thermally conductive substrate 11b. The thermally conductive substrate 11b is fixed to the reflector 11c and forms an optical system that radially emits the first light L1 toward the reflector 10B located below it. By fixing it to an outer frame (not shown), an independent lamp unit is formed. This outer frame is then fixed by attaching it to the housing 13. Furthermore, the thermally conductive substrate (light source substrate) 11b on which the LED light source 11a is mounted and the control board 17 on which the drive circuit for driving the LED light source 11a are provided are arranged separately within the lamp chamber 14. These are electrically connected via a wiring cord called a harness and are spaced apart to protect the drive circuit from the heat emitted by the LED light source 11a.

[0025] In this embodiment, by adjusting multiple reflective surfaces 11c, the illumination range on the screen is made to have a horizontally elongated light distribution centered on the optical axis. Specifically, when plotting the angle (°) centered on the optical axis on the horizontal axis and the luminous intensity (cd) on the vertical axis, the horizontal direction is approximately 6°, creating a symmetrical shape, while the vertical direction is narrowed to approximately 5°. However, in the vertical direction, the upward direction is less than 5°, and the downward direction has an asymmetrical shape with a broad base from 5° to around 10° at a brightness of 20-25% of the maximum illuminance, thereby increasing the amount of illumination on the road surface. In addition to adjusting the multiple reflective surfaces 11c, a refractive lens may also be provided below the window portion 15C of the outer lens to increase downward light.

[0026] (Drawing lamp unit) The drawing lamp unit 12 is a lamp unit that projects a predetermined drawing pattern toward the road surface diagonally to the side of the central light-emitting unit 11 that illuminates the front of the bicycle. In this embodiment, as shown in Figures 2 and 3, one independent lamp unit is arranged on each side of the central light-emitting unit 11. The left light-emitting unit 12L and the right light-emitting unit 12R each have independent optical systems and are controlled to be switched on and off independently.

[0027] Figure 5 is a schematic longitudinal cross-sectional view illustrating the left light-emitting unit 12L. Since the right light-emitting unit 12R has the same configuration as the left light-emitting unit 12L, a description of the configuration of the right light-emitting unit 12R is omitted. The left light-emitting unit 12L comprises an LED light source 21, a thermally conductive substrate 22 on which the LED light source 21 is mounted, two condenser lenses 23 for making the second light L2 emitted from the LED light source 21 into parallel rays, a projection lens 24 for projecting the second light L2 emitted from the condenser lenses 23 forward, and an image forming unit 25 positioned between the condenser lenses 23 and the projection lens 24, thus constituting a drawing optical system. The thermally conductive substrate 22, the condenser lenses 23, the image forming unit 25, and the projection lens 24 are fixed to an outer frame 26. The outer frame 26 is provided with screw holes (not shown), and is configured to be detachably fixed by screwing it to the lower housing 13a of the bicycle lighting device 10. Instead of using two condenser lenses 23 to create parallel light rays, a single lens or reflector may be used to direct the second light L2 emitted from the LED light source 21 into the projection lens 24.

[0028] The image forming unit 25 is the part that forms an image to be projected onto the road surface using the second light L2 emitted from the LED light source 21. In this embodiment, an image film fixing frame 25a, which has an opening corresponding to the condenser lens 23, is fixed to the outer frame 26, and a separately prepared image film 25b can be inserted and removed from above the image film fixing frame 25a. The image film 25b has a desired design, such as a figure or characters to be drawn on the road surface, drawn on it by a transparent film or other method. The transparent film used as the base material is preferably made of a material with excellent light transmittance and minimal deformation due to heat, such as a glass plate, and more preferably tempered glass with enhanced resistance to vibration. Other transparent resin plates such as acrylic resin or polycarbonate may also be used. An image film 25b can also be made by drawing a design on the surface of a thin film-like glass with a thickness of 0.1 mm, and sandwiching both sides of the glass film with, for example, 2 mm thick acrylic resin. Alternatively, a design can be drawn by processing a metal plate to form a window (transparent part) corresponding to the desired design. In this way, by replacing the image film 25b, any image can be projected and drawn onto the road surface. In this embodiment, a physically replaceable image film 25b is used, but it may also be fixed to the frame instead of being replaceable. Furthermore, although the cost will be higher, a variable image forming unit 25 can be made in which the design can be changed by electrical means. For example, a liquid crystal element with multiple pixels can be placed at the position of the image film fixing frame 25a. By electrically switching control each pixel of the liquid crystal element, the transmitted light can be modulated and the image can be changed. Alternatively, a laser light source could be used as the light source, and the reflection direction of the light from the laser light source could be controlled by an electrically controlled mirror to draw the image.

[0029] The light emitted from the left light-emitting unit 12L illuminates the road surface diagonally to the left in front of the vehicle, drawing an image formed by the image forming unit 25 onto the road surface. As mentioned above, the light distribution standard for bicycle headlights is a narrow range centered on the optical axis. That is, it is sufficient to satisfy a predetermined illuminance value at positions of 4° to the left and right on the screen 10m in front of the headlight. Therefore, simply satisfying the light distribution standard will result in the road surface in front of the bicycle, especially in areas to the sides of 4° to the left and right, being dark. The left light-emitting unit 12L mainly illuminates the area to the left at an angle greater than 4° to the left, and closer to an area closer than 10m in front. Similarly, the right light-emitting unit 12R mainly illuminates the area to the right at an angle greater than 4° to the right, and closer to an area closer to an area closer than 10m in front. In this embodiment, as mentioned above, the central light-emitting unit 11 also has an asymmetrical light distribution characteristic in the vertical direction, illuminating a wide angle downwards, i.e., towards the road surface. Therefore, the bicycle lighting device 10 has a central light-emitting unit 11 that illuminates the central part along the optical axis on the road surface closer than 10 meters in front, while the left light-emitting unit 12L and the right light-emitting unit 12R illuminate diagonally in front of the rider to the left and right, respectively. This widens the illuminated area of ​​the road surface, making it easier for the rider to see their feet. Furthermore, the left light-emitting unit 12L and the right light-emitting unit 12R each project an image formed by the image-forming unit 25 onto the road surface. Therefore, information corresponding to the projected image can be provided not only to the rider but also to people, cars, bicycles, and other people in the surrounding area.

[0030] (Control board, battery) The battery 16 and the control board 17 are fixed to the lamp unit mounting section of the lower housing 13a. The control board 17 is provided with connectors and circuit components (not shown). The connectors are electrically connected to the LED light sources of each light-emitting unit by harnesses that connect to the light source board 11b of the central light-emitting unit 11, and to the respective light source boards 22 of the left light-emitting unit 12L and the right light-emitting unit 12R. Figure 6 is a block diagram illustrating the lighting control of the bicycle lighting device 10. The control board 17 is provided with a lighting drive circuit 30 and a power control circuit.

[0031] The lighting drive circuit 30 is connected to the central light-emitting unit 11, the left light-emitting unit 12L, and the right light-emitting unit 12R, and includes a first lamp control unit 31, a second lamp control unit 32, and a third lamp control unit 33 that independently control the lighting state of the light source of each light-emitting unit, as well as a flashing circuit 37 for flashing the left light-emitting unit 12L and the right light-emitting unit 12R. A switch SW is also connected for the rider to arbitrarily operate the switching of the lighting control of the bicycle lighting device 10. Furthermore, the output signal of the illuminance sensor 34 is connected to be input to the lighting drive circuit 30. The output of the power control circuit 35 is also input to the lighting drive circuit 30. The power control circuit 35 is housed in the housing 13 and is a circuit that supplies power from the output of the battery 16 to each light-emitting unit 11, 12L, and 12R that is appropriate for lighting each light-emitting unit. An external power supply 36 is also connected to the power control circuit 35 to supply power to supplement or replace the battery 16. The battery 16 is a rechargeable battery such as a dry cell or a nickel-metal hydride battery. The external power supply 36 is a dynamo or, if the bicycle is an electric bicycle, a power supply for the electric bicycle.

[0032] As shown in Figure 3, the illuminance sensor 34 is fixed to the lower housing 13a and outputs a signal corresponding to the brightness of ambient light entering through a transparent window (not shown) provided in the upper housing 13b. The central light-emitting unit 11 is set to light up when the output value from the illuminance sensor 34 becomes a signal corresponding to a value that is darker than the value that occurs when the illuminance is darker than a predetermined brightness level (first threshold). The left light-emitting unit 12L and the right light-emitting unit 12R are set to light up when a second threshold different from the first threshold is reached. The second threshold is a value that corresponds to an output value that is brighter than the brightness corresponding to the first threshold. This allows, for example, road surface drawing to be performed earlier than when the central light-emitting unit 11 lights up at dusk, and to warn the surroundings from a bright stage before it gets dark.

[0033] The flashing circuit 37 is connected to the left light-emitting unit 12L and the right light-emitting unit 12R, respectively, and independently flashes each LED light source 21. By flashing the left light-emitting unit 12L and the right light-emitting unit 12R, they can be easily noticed by those around them, thereby improving recognition. The flashing circuit 37 can also be omitted when flashing is not required. Furthermore, since all light sources in the central light-emitting unit, the right light-emitting unit, and the left light-emitting unit are LEDs, their control circuits can be made common and simplified.

[0034] (Road surface light distribution pattern) Figure 7 is a schematic diagram showing the road surface illumination pattern of the bicycle lighting device 10, represented by an isolarium curve. It shows the light distribution pattern when the bicycle lighting device 10 is installed 1 meter above the road surface, with the optical axis of the central light-emitting unit 11 tilted downwards by 5°, illuminating the road surface (horizontal plane). The horizontal axis represents the angle (°) with the optical axis as the center (0°), and the vertical axis represents the distance (m) from the bicycle lighting device 10. The road surface illumination pattern PC of the central light-emitting unit 11 is shown in solid form as an isolarium curve, while the road surface illumination patterns PL and PR of the left light-emitting unit 12L and right light-emitting unit 12R are shown as dotted lines indicating their illumination ranges. Since the left light-emitting unit 12L and right light-emitting unit 12R project images formed by the image-forming unit 25 onto the road surface, the illumination range is shown rather than the projected image on the road surface.

[0035] As can be seen from Figure 7, the road surface illumination patterns PL and PR of the drawing lamp unit 12 illuminate at a shorter distance and at an oblique angle to the side compared to the road surface illumination pattern PC of the central light-emitting unit 11. In particular, if the pattern is drawn within 5 meters on the near side, more preferably within a range of 2 to 3 meters, at an angle of 2 to 4 degrees to the left and right, it is easier to draw without overlapping with the road surface illumination pattern PC of the central light-emitting unit 11. Furthermore, since the pattern is drawn on the road surface at a distance both near and away from the bicycle, the design becomes easier for surrounding pedestrians and drivers of other vehicles to recognize, and it also becomes easier to recognize which bicycle the road surface illumination pattern belongs to. In a simple experiment, a pattern that had an illuminance of 1000 lx when illuminated at a distance of 1 m had an illuminance of 300 lx when illuminated at a distance of 2 m, and 100 lx at a distance of 4 m. From these experimental results, although it will vary depending on the illuminating optical system, the brightness of the light source, the drawing pattern, etc., the trend is considered to be similar, and a distance of approximately 5 m is likely to be a practical distance at which the design drawn on the road surface can be recognized. At a distance exceeding 5 meters, the rider is too far from their own bicycle, making it difficult to perceive the relationship with the bicycle performing the road marking. Therefore, it is preferable to draw the markings at a position close to the bicycle performing the markings, and at an angle to the front. Ideally, the marking size should be 1 meter or longer, centered at a distance of 4 to 5 meters, and the brightness should be sufficient for recognition. Furthermore, considering the lighting function while riding, drawing too close to the bicycle is impractical. Therefore, the range described above provides a well-balanced marking area for both the cyclist and those around them.

[0036] Figure 8 is a plan view of the design illustrating specific examples of road surface drawing patterns for the road surface illumination patterns PL and PR shown by dotted lines in Figure 7. Four types of road surface drawing patterns (A) to (D) are illustrated, each with the road surface illumination pattern PL and road surface illumination pattern PR arranged symmetrically in front of the bicycle 1, with the bicycle as the center. (A) is a linear design, (B) and (C) are arrow-shaped designs indicating the direction of travel of the bicycle 1, and (D) shows a design that combines geometric figures with a design that conveys a message. In any of the road surface drawing patterns, the road surface illumination patterns PL and PR are projected onto the road surface in conjunction with the central light-emitting unit 11 that illuminates the light distribution pattern of the bicycle headlight, so the amount of illumination on the road surface increases compared to the case with only the central light-emitting unit 11, making the road surface near the bicycle brighter and easier to ride. In addition, it becomes possible to inform those around the bicycle of its presence without directly looking at the bicycle 1. In particular, it enhances safety by making the presence known through road markings without generating upward light that could dazzle oncoming drivers. Furthermore, if the projected image has a meaningful design, that message can be conveyed to those around.

[0037] If the road surface illumination pattern PL and PR is too small, visibility from the surroundings will be poor. The effect of illuminating the area in front of the bicycle to improve visibility for the cyclist is also small. If the size of the drawing when drawn 4m ahead is less than 0.5m, it is too small. A drawing size of around 1m, or between 0.8m and 2m, provides a good balance between visibility and illumination function, and the lamp unit can be made smaller. Furthermore, visibility can be further improved by using a colored light other than white. By using a color other than white, it is possible to make the presence known without blending in with ambient light such as streetlights and security lights. Since the human eye has high visual sensitivity to green, it is preferable to use a color in the green family.

[0038] [Second Embodiment] Next, a bicycle lighting device according to a second embodiment of the present invention will be described using Figures 9 and 10. Figure 9 is a schematic diagram showing a bicycle lighting device of the second embodiment, where (A) is a schematic explanatory diagram showing a horizontal cross-section and (B) is a front view. In the first embodiment, the bicycle lighting device 10 had three lamp units, with a central light-emitting unit 11 that functions as a headlight 11 and a pair of drawing lamp units 12 provided on both sides thereof. In the second embodiment, it is the same in that it has three lamp units, with a central light-emitting unit 11 that functions as a headlight 11 and a pair of drawing lamp units 12, but it differs in that it is a bicycle lighting device 40 further equipped with a second drawing lamp unit 42 between the central light-emitting unit 11 and the drawing lamp units 12. In addition, the position where the illuminance sensor 34 is installed is near the center in the front-to-back direction. Other points are the same as in the first embodiment, so the same reference numerals are used and their explanation is omitted here.

[0039] (Second drawing lamp unit) The second drawing lamp unit 42 is installed between the central light-emitting unit 11 and the left light-emitting unit 12L. The second drawing lamp unit 42 has the same configuration as the light-emitting unit 12 described in the first embodiment and is configured to draw a predetermined image on the road surface. The second drawing lamp unit 42 draws an image on the road surface in front of the bicycle 1, superimposed on the road surface illumination pattern PC illuminated by the central light-emitting unit 11. In addition, the road surface illumination pattern P2 by the second drawing lamp unit 42 is illuminated such that at least a portion of it is located between the road surface illumination pattern PL illuminated by the left light-emitting unit 12L and the road surface illumination pattern PR illuminated by the right light-emitting unit 12R. The second drawing lamp unit 42 may be installed between the central light-emitting unit 11 and the right light-emitting unit 12R, or on either side of the central light-emitting unit 11. Since it draws an image superimposed on the road surface illumination pattern PC, it is preferable to install it near the central light-emitting unit 11. The second drawing lamp unit 42 is also connected to the control board 17, similar to the central light-emitting unit 11 and the drawing lamp unit 12, and its on / off state is controlled by a fourth lamp control unit (not shown).

[0040] Figure 10 is a schematic plan view illustrating the road surface illumination pattern emitted by a bicycle lighting device. It primarily shows the area within 6m in front of the bicycle. Three types of examples are shown in Figures 10(A), 10(B), and 10(C). In each of the drawings in Figures 10(A) to (C), the area enclosed by the ellipse shown in the center of the front of the bicycle 1 schematically shows the illumination area of ​​the road surface illumination pattern PC emitted by the central light-emitting unit 11. The road surface illumination pattern PC also illuminates the road surface further away from the drawing lamp units 12L, 12R and the second drawing lamp unit 42, but in Figure 10, it is simplified for the sake of simplicity. In Figure 10(A), the drawing lamp units 12L and 12R each draw two diagonally extending vertical lines to form road surface illumination patterns PL and PR, and the second drawing lamp unit 42 draws four horizontally extending linear images at a position overlapping with the road surface illumination pattern PC, with the width increasing as the lines move further away. In Figure 10(B), each of the drawing lamp units 12L and 12R draws an image that mimics multiple arrow shapes extending diagonally vertically, and the second drawing lamp unit 42 draws an image of four rectangular shapes at a position that overlaps with the road surface illumination pattern PC. In Figure 10(C), each of the drawing lamp units 12L and 12R forms road surface illumination patterns PL and PR by drawing two straight lines extending diagonally vertically, and the second drawing lamp unit 42 draws an image of three arrows at a position that overlaps with the road surface illumination pattern PC, with the arrows becoming larger as they move away from the road surface. Note that the drawing patterns are not limited to these examples and can be of various shapes.

[0041] In Figure 10(A), the four rectangular images drawn in a position overlapping with the road surface illumination pattern PC extend laterally beyond the illumination area of ​​the road surface illumination pattern PC illuminated by the central light-emitting unit 11. In cases like this, where the pattern illuminated by the second drawing lamp unit 42 illuminates an area laterally than the illumination area of ​​the road surface illumination pattern PC, the left light-emitting unit 12L and the right light-emitting unit 12R can be omitted, and the functions of the left light-emitting unit 12L and / or the right light-emitting unit 12R can be given to the second drawing lamp unit 42. It is also obvious that the pattern illuminated by the second drawing lamp unit 42 is not limited to the straight lines shown in Figure 10(A), but can be any other pattern.

[0042] Although embodiments of the present invention have been described above, the above-described modifications of embodiments are merely illustrative in all respects. The present invention is not to be interpreted as being limited by these descriptions. The present invention can be modified in various other ways by adding, omitting, substituting, and otherwise changing its configuration without departing from its spirit. For example, the lighting drive circuit 30 may be configured to receive a signal in response to the brake operation of the bicycle 1, and based on the signal corresponding to the input brake operation, the timing of the lighting or flashing interval and the color of the light emitted by the drawing lamp unit 12 may be changed in response to the brake operation, making it easier for those around to recognize that the brakes are being applied. Furthermore, for example, a sensor element such as an acceleration sensor may be installed in the bicycle lighting devices 10, 40, and the change in the center of gravity of the bicycle 1 may be determined in response to the sensor signal such as the acceleration sensor, and a left turn, right turn, or braking operation may be determined in response to the change in the center of gravity of the bicycle, and if it is a left turn, only the left light-emitting unit 12L of the drawing lamp unit 12 may be lit, and if it is a right turn, only the right light-emitting unit 12R may be lit, and so on. Furthermore, in this embodiment, the left light-emitting unit 12L and the right light-emitting unit 12R are separate light-emitting units from the central light-emitting unit 11, but they may be made into a single unit by sharing common parts. [Industrial applicability]

[0043] This invention is applicable not only to regular bicycles but also to electric assist bicycles. It can also be applied to kick scooters equipped with headlights. Similar to the light distribution pattern of bicycle headlights, headlights of vehicles other than automobiles and motorcycles that travel on roads and have a narrow light distribution pattern in the left-right direction are included in the definition of bicycle headlights in this invention, and can be applied to forward lighting devices equipped with such bicycle headlights. [Explanation of symbols]

[0044] 1…Bicycle 10,40…Bicycle lighting devices (bicycle front lighting devices) 11…Central light-emitting unit (headlight) 11a…LED light source 11b…Thermal conductive substrate (light source substrate) 11c…Reflector 11c 11c1…Reflective surface 12…Drawing lamp unit 12L…Left light-emitting unit 12R…Right light-emitting unit 13…Housing (case) 13c…Fixed part 14…Light room 15…Outer lens 16…Battery 17…Control board 21…LED light source 22…Thermal conductive substrate (light source substrate) 23...Condenser lens 24…Projection lens 25…Image forming unit 26…Outer frame 30... Lighting drive circuit 34…Illuminance sensor 35...Power control circuit 36…External power supply 37...Flashing circuit 42…Second drawing lamp unit M…Center line PC…Road surface illumination pattern (central light-emitting unit) PL…Road surface illumination pattern (left light-emitting unit) PR...Road surface illumination pattern (right light-emitting unit) P2…Road surface illumination pattern (second drawing lamp unit)

Claims

1. A central light-emitting unit is located in the central region when viewed from the front and is formed to emit light forward. A right light-emitting unit is provided, which is shifted to the right of the center line of the central light-emitting unit when viewed from the center line of the central light-emitting unit, and is formed to emit light in a direction that is to the right, forward, and in front of the central light-emitting unit; A left light-emitting unit is provided, which is shifted to the left of the center line of the central light-emitting unit when viewed from the center line of the central light-emitting unit, and is formed to emit light in a direction that is to the left, forward, and in front of the central light-emitting unit; A control board equipped with a lighting drive circuit that controls the lighting state of the central light-emitting unit, the right light-emitting unit, and the left light-emitting unit, The housing comprises a light chamber that houses the central light-emitting unit, the right light-emitting unit, the left light-emitting unit, and the control board, The housing has a fixing part formed therein for fixing it to a bicycle. At least one of the light-emitting units, the right light-emitting unit and the left light-emitting unit, is provided with a drawing optical system consisting of an LED light source and an image forming unit provided in front of the direction of illumination of the LED light source. The drawing optical system is a bicycle lighting device that emits light to draw a predetermined image toward the road surface in front of the central light-emitting unit, according to the light distribution pattern of the central light-emitting unit.

2. The bicycle lighting device according to claim 1, characterized in that the image forming section of at least one of the right light-emitting unit and the left light-emitting unit is provided with an image film fixing frame and has an image film that can be inserted into and removed from the image film fixing frame.

3. The bicycle lighting device according to claim 1, characterized in that the image forming section of at least one of the right light-emitting unit and the left light-emitting unit is a variable type image forming section whose design can be changed by electrical means.

4. The control board is The system comprises a first control unit that controls the lighting state of the light source of the central light-emitting unit, and a second control unit that controls the lighting state of the respective light sources of the right light-emitting unit and the left light-emitting unit. The first control unit performs continuous lighting in response to the output signal of the illuminance sensor or in response to the switch operation. The bicycle lighting device according to any one of claims 1 to 3, wherein the second control unit performs flashing illumination independently of the illumination of the light source of the central light-emitting unit by the first control unit.

5. The bicycle lighting device according to any one of claims 1 to 4, characterized in that the light sources of the central light-emitting unit, the right light-emitting unit, and the left light-emitting unit are LEDs.

6. A bicycle equipped with a bicycle lighting device according to any one of claims 1 to 5.

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