JP2008100629A - Lighting system for bicycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system for a bicycle capable of enhancing the visibility thereof from an oncoming car while the bicycle is stopped. <P>SOLUTION: The lighting system comprises a dynamo 3 for power generation by the rotation of a wheel, five white LEDs 9, 10 forming a light source of a headlight 6, a lighting circuit 25 for lighting the five white LEDs 9, 10 by the power of the dynamo. The power of the dynamo generated while the bicycle is running is charged to a capacitor 23 and the three light emitting diodes 10 which are a part of five light emitting diodes are blinked by the power charged in the capacitor when the bicycle is stopped. When the bicycle is stopped, a part of the LEDs out of the plurality of LEDs used for the light source of the headlight are blinked, and any separate light source when the bicycle is stopped is unnecessary. In addition, only a part of LEDs are blinked, and the necessary power can be reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a bicycle lighting device that illuminates the front of a bicycle with a headlamp.

Conventionally, as a bicycle lighting device, a dynamo that generates electricity by rotating wheels while a bicycle is running is provided, and a light bulb that is a light source of a headlamp is turned on while the bicycle is stopped by the power of the dynamo. In general, the light is turned off. This makes it impossible to inform the oncoming vehicle of his / her position when stopping. Therefore, a light source such as a light emitting diode (hereinafter referred to as LED) separate from the light bulb is built in the headlamp, and a capacitor is charged by dynamo power generation during driving, and this capacitor is connected to the capacitor when stopped. Japanese Patent Application Laid-Open No. H10-228667 discloses an LED that is turned on by stored electricity and informs an oncoming vehicle of its own position while the vehicle is stopped.
JP 2003-16810 A

  In Patent Document 1, there is a problem in that an LED is required in addition to the light bulb in order to notify the user's position at the time of stop, and two types of light sources must be prepared. If the light bulb is turned on or blinking when the light bulb is stopped without using the LED, the power stored in the capacitor is not sufficient, and a secondary battery needs to be used. There is a problem that it takes a long time.

  An object of the present invention is to provide a bicycle lighting device that can improve visibility from an oncoming vehicle while stopping without using two types of light sources and without using a secondary battery. .

  In order to solve the above-described problems, a bicycle lighting device according to the present invention generates dynamo that generates power by rotating a wheel of a bicycle, a plurality of light-emitting diodes that serve as a light source for a headlamp, and power generated while the bicycle is running. A lighting circuit for supplying dynamo power to the plurality of light emitting diodes to light the plurality of light emitting diodes; a charging circuit for supplying dynamo power generated while the bicycle is running to a capacitor for charging; and It has an afterglow circuit that blinks or lights a part of the plurality of light emitting diodes by the electric power stored in the capacitor when the bicycle is stopped.

  An example of the plurality of light emitting diodes is a white light emitting diode (white LED).

  According to the bicycle lighting device of the present invention, one type of light source such as a plurality of light-emitting diodes is used as the light source of the headlamp, and when the bicycle is stopped, some of the plurality of LEDs blink. Or since it is made to light, a separate light source is not required in order to improve the visibility at the time of a stop, and cost can be reduced. In addition, since some of the LEDs are only blinked or lit when stopped, the power required for that purpose can be reduced, and a charging capacitor is sufficient in time, and there is no need to use a secondary battery. In particular, blinking can advantageously reduce the required power and improve visibility.

  An embodiment of a bicycle lighting device of the present invention will be described with reference to the drawings. The bicycle lighting device includes a hub dynamo 3 disposed on the hub axle of the front wheel 2 of the bicycle 1 and a headlamp 6 attached to a front fork 4 on the side of the front wheel 2 via a bracket 5. The hub dynamo 3 generates electric power by the rotation of the front wheel 2, and the structure thereof is a well-known one that is also found in, for example, Japanese Patent Application Laid-Open No. 2001-327139, and detailed description thereof is omitted.

  As shown in FIGS. 2 and 3, the headlamp 6 has an outer case composed of a main body case 7 and a front lens 8. Inside, five light emitting diodes 9, 9, 10, 10, 10 are used as light sources. in use. These light emitting diodes are white light emitting diodes (white LEDs) that emit white light. The five white LEDs are divided into two, 9, 9 on the inner side near the front wheel 2 and three, 10, 10, 10 on the outer side away from the front wheel.

  FIG. 4 is an electric circuit diagram, which will be described below. The output of the hub dynamo 3 is alternating current, and is converted into direct current by a rectifier circuit 11 formed of a diode bridge. Since the output voltage of the hub dynamo 3 varies depending on the speed, the voltage is controlled by the Zener diode 13 of the constant voltage circuit 12 and the voltage is smoothed by the capacitor 14. The smoothed voltage is supplied to an illuminance detection circuit 15 that detects ambient brightness.

  The photosensor of the illuminance detection circuit 15 employs a phototransistor 16, and the brightness is replaced with a current change of the phototransistor 16, and the comparator 17 compares it with a reference voltage. When the surroundings become dark, almost no current flows through the phototransistor 16, the output level of the comparator 17 becomes “L”, the output level of the comparator 18 also becomes “L”, and the transistor Q1 is turned on. When the surroundings become bright, a current flows through the phototransistor 16, the output level of the comparator 17 becomes “H”, the output level of the comparator 18 also becomes “H”, and the transistor Q1 is turned off.

  On the other hand, while the bicycle is running, the voltage of the capacitor 14 of the constant voltage circuit 12 is sufficiently high, so that the output level of the comparator 20 of the speed detection circuit 19 is “L” and the transistor Q2 is turned on. While the bicycle is stopped, the voltage of the capacitor 14 also decreases, the output level of the comparator 20 becomes “H”, and the transistor Q2 is turned off.

  When the bicycle is running and the surroundings are dark, current flows through the white LEDs 9 and 9 via the transistors Q1 and Q2, and the transistor Q3 is also turned on, so that current also flows through the white LEDs 10, 10, and 10. Accordingly, the five LEDs 9, 9, 10, 10, 10 are lit. In this case, the illuminance detection circuit 15 and the speed detection circuit 19 supply the dynamo power generated during traveling as claimed in claim 1 to the plurality of light-emitting diodes, thereby providing the plurality of light-emitting diodes. A lighting circuit 25 for lighting is configured.

  When the vehicle is dark during traveling, the charging capacitor 23 of the charging circuit 22 (constant voltage circuit) in the afterglow circuit 21 is charged.

  When the bicycle is stopped, the transistor Q2 is turned off, so that no current flows to the two white LEDs 9, 9, and the light is turned off. On the other hand, the voltage of the charging capacitor 23 is applied to the three white LEDs 10, 10, 10 via the transistor Q 4 of the afterglow circuit 21. Since the transistor Q4 is repeatedly turned on and off by the multivibrator 24, the voltage of the charging capacitor 23 is applied to the three white LEDs 10 only when the transistor Q4 is on, and the three white LEDs 10 blink. This blinking continues for a predetermined time until the electricity stored in the capacitor 23 runs out.

  Therefore, when the vehicle is stopped, the on-coming vehicle can be notified of the position of the vehicle by blinking the three LEDs 10 and safety can be improved. The three LEDs 10, 10, 10 blinking during the stop are used to illuminate the front as the light source of the headlamp together with the other two LEDs 9, 9 during traveling. It is not prepared as a light source, and the cost can be reduced.

  In addition, since the three LEDs 10, 10 and 10 are blinking during stoppage, the visibility is improved, and not all five LEDs are blinked, but three of them are blinked. Less power is required for blinking, and the charging capacitor 23 can sufficiently store the required power without using a secondary battery, and costs can be reduced from this point.

  In addition, the three LEDs 10 flashing during stoppage are arranged on the side away from the front wheel, that is, outside as shown in FIG. 3, so that the visibility from the side as well as the front of the bicycle is improved. Is advantageous.

  The stopped LED 10 may be turned on instead of blinking. In this case, the multivibrator 24 and the transistor Q4 of the afterglow circuit 21 may be omitted. When the light is turned on, the required power is slightly larger than when the light is flashed, but the required power can be stored by the charging capacitor 23.

  In the above embodiment, the white LED is used as the LED. However, the color is not limited to white as long as it is a color suitable for irradiating the front (for example, light yellow). Also, the dynamo is not limited to the hub dynamo and may have a roller that rotates in contact with the side surface of the wheel.

  By the way, since the LED has a characteristic that when the voltage applied to the LED is low, the amount of light emission decreases and the light intensity also decreases, when the bicycle speed decreases, the dynamo power generation voltage decreases, and the LED Insufficient light intensity is not sufficient, and the front cannot be sufficiently irradiated.

  Therefore, if the full-wave voltage doubler rectifier circuit 30 as shown in FIG. 5 is used as the rectifier circuit for rectifying the generated voltage instead of using the rectifier circuit 11 as shown in FIG. Even if the voltage is low, a sufficient voltage can be applied to the LED to prevent a decrease in luminous intensity.

  In other words, the full-wave voltage doubler rectifier circuit 30 alternately converts the positive half cycle and the negative half cycle of the AC power generation voltage of the dynamo 3 into direct current by the two diodes 31 and 32, and charges the capacitors 33 and 34, respectively. To do. The DC voltage taken out as an output is the sum of the voltages of the two capacitors 33 and 34. Since the voltages of the capacitors 33 and 34 are approximately the maximum value of the AC power generation voltage, the output DC voltage is almost twice the dynamo AC power generation voltage, and a high voltage can be obtained. Therefore, a sufficient voltage can be applied to the LED even at a low speed of the bicycle, and a decrease in luminous intensity can be prevented.

It is a side view of the front wheel vicinity of the bicycle which attached the lighting device for bicycles of the present invention. It is a perspective view of the headlamp of the bicycle lighting device. It is a front view of the headlamp. It is an electric circuit diagram of the lighting device for bicycles of the present invention. It is another Example of the rectifier circuit of the lighting apparatus for bicycles.

Explanation of symbols

3 Hub dynamo (Dynamo)
6 Headlamp 9 Light-emitting diode (LED)
10 Light emitting diode (LED)
25 lighting circuit 15 illuminance detection circuit 19 speed detection circuit 23 charging capacitor 22 charging circuit 21 afterglow circuit

Claims (4)

  A dynamo that generates electricity by rotating a wheel of a bicycle, a plurality of light emitting diodes that serve as a light source for a headlight, and a plurality of light emitting diodes that supply power to the dynamo that is generated while the bicycle is running. A lighting circuit for lighting the light emitting diode, a charging circuit for supplying power to a capacitor by charging dynamo power generated while the bicycle is running, and a power stored in the capacitor when the bicycle is stopped. A bicycle lighting device having an afterglow circuit that blinks or lights some of the light emitting diodes. The lighting circuit detects ambient brightness, and turns on when the brightness becomes dark to supply dynamo power to the light emitting diode, and turns off when the brightness becomes bright to turn off the power supply to the light emitting diode The bicycle lighting device according to claim 1, further comprising a detection circuit.   The headlamp is attached to the side of the front wheel of the bicycle, and the plurality of light emitting diodes are arranged separately on the inner side close to the front wheel and the outer side away from the front wheel, and the light emitting diodes that flash or light when stopped are The bicycle lighting device according to claim 1, wherein the lighting device is a light emitting diode located outside.   The bicycle lighting device according to any one of claims 1 to 3, wherein the plurality of light emitting diodes are white light emitting diodes.