Generator powered bicycle headlamp and electrical circuit

• US 7,275,844 B2
• Filed: 06/11/2003
• Issued: 10/02/2007
• Est. Priority Date: 06/11/2002
• Status: Expired due to Fees

• Current Assignee: Akidenki Kabushikigaisya
• Original Assignee: Akidenki Kabushikigaisya
• Inventors: Watanabe, Masashi
• Primary Examiner(s): Lee; Jong-Suk (James)
• Assistant Examiner(s): Negron; Ismael
• Application Number:
  US10/516,513
• Publication Number:
  US 20050243545A1
• Time in Patent Office: 1,574 Days
• Field of Search: 362/192, 362/473, 362/475, 362/244, 362/245, 310/73, 340/432
• US Class Current: 362/473
• CPC Class Codes: B62J 6/01 Electric circuits
• CPC Class Codes: B62J 6/028 specially adapted for rider-propelled cycles with or without additional source of power
• CPC Class Codes: B62J 6/06 Arrangement of lighting dynamos or drives therefor
• CPC Class Codes: B62J 6/20 Arrangement of reflectors , e.g. on the wheel spokes pedals incorporating reflectors B62M3/12 ; Lighting devices mounted on wheel spokes
• CPC Class Codes: H02K 7/1869 Linear generators; sectional generators

Abstract

A bicycle headlamp including: a rotor having a plurality of magnet plates attached to spokes of a bicycle wheel, each magnet plate including a plurality of magnets disposed at regular circumferential spacings with alternating south and north poles; and a stator including a power-generating coil disposed in a fixed position to face the magnetic pole faces of the magnet plates. A case includes at least a headlamp electrical circuit for establishing resonance with a certain relative speed of the magnets by means of the power-generating coil and a capacitor connected in series, and for rectifying, smoothing out, and outputting electric power obtained from the power-generating coil. Also included are a light-emitting diode and a condenser lens for focusing light emitted from the light emitting diode in front of the bicycle and for illuminating the roadway.

Claims

1. A bicycle headlamp comprising:

a rotor comprising a plurality of magnet plates attached to spokes of a bicycle wheel along the circumference of the wheel, each magnet plate having a form of an arc of a certain circle and comprising a plurality of magnets disposed at regular circumferential spacings with alternating south and north poles;

a stator comprising a power-generating coil comprising a coil and an iron core disposed in a fixed position to face the magnetic pole faces of the magnet plates of the rotor; and

a case separated from the stator, or for containing all of the stator, wherein the case contains at least a headlamp electrical circuit comprising a resonance circuit formed of the power-generating coil of the stator and a capacitor connected in series with the-power-generating coil, and having, as a resonant frequency, a power-generation frequency determined by the positions where the magnets and the power-generating coil are disposed, when the bicycle is pedaled at a predetermined speed, and a rectifying and smoothing circuit for rectifying, smoothing, and outputting electric power obtained from the power-generating coil of the resonance circuit, a plurality of light-emitting diodes that are lit by the electric power supplied from the headlamp electrical circuit, and a condenser lens for focusing light emitted from the plurality of light-emitting diodes in front of the bicycle and for illuminating the roadway,

wherein the lens is a dome-shaped lens disposed for each of the plurality of light-emitting diodes, the dome-shaped lens has a curvature, a diameter, and a thickness calculated to obtain a specified level of illumination in a specified circle at a specified distance by focusing light; and

a reflector is provided on a flat-plate portion above the lens, by applying a treatment for producing diffused reflection, so that approaching of the bicycle can be noticed ahead of the bicycle.

2. A bicycle headlamp according to claim 1, wherein the stator, comprising the power-generating coil, the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case as a unit.

3. A bicycle headlamp according to claim 1, wherein the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case;

and the stator, comprising the power-generating coil, is separately disposed outside the case.

4. The bicycle headlamp according to claim 1, wherein the predetermined speed is 15 km/h.

5. A bicycle headlamp according to claim 1, wherein the stator comprises the magnet plates attached to the spokes of the bicycle along the circumference of the wheel, in a continuous ring shape or in separate positions.

6. A bicycle headlamp according to claim 5, wherein the stator, comprising the power-generating coil, the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case as a unit.

7. A bicycle headlamp according to claim 5, wherein the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case;

and the stator, comprising the power-generating coil, is separately disposed outside the case.

8. A bicycle headlamp according to claim 1, wherein the plurality of light-emitting diodes include a white light-emitting diode with a luminous intensity of 2 cd or higher, and the lens has a focal length such that a certain level of illumination is ensured at a specified distance.

9. A bicycle headlamp according to claim 8, wherein the stator, comprising the power-generating coil, the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case as a unit.

10. A bicycle headlamp according to claim 8, wherein the headlamp electrical circuit, the plurality of light-emitting diodes, and the condenser lens are contained in the case;

and the stator, comprising the power-generating coil, is separately disposed outside the case.