JPS5854865Y2 - Bicycle generator - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a bicycle power generation device that is attached to the outer periphery of the wheel shaft of a bicycle and generates electricity by rotating a coil and a magnet relative to each other as the wheel rotates.

Conventionally, a ring-shaped ferrite magnet is used, and N is placed on the inner circumference.
A bicycle power generation device in which the poles and S poles are polarized and magnetized sequentially is well known, but since it is integrally molded into an annular shape, it has been difficult to make the entire device radially anisotropic.

Therefore, although we used isotropic materials, the magnetic flux density was low, so the magnetic force was weak and it was difficult to obtain the required output.
Furthermore, since a large magnet must be used in order to produce output, it has the disadvantage of being large, heavy, and expensive.

The present invention consists of molding a ring-shaped magnet into multiple pieces, making each piece anisotropic within a normal magnetic field, and assembling these pieces into a ring-shaped piece by a simple means to construct an annular anisotropic ring-shaped magnet. This is designed to generate high magnetic flux in the radial direction, thereby eliminating the drawbacks of the conventional method.

Next, an embodiment of the present invention shown in the accompanying drawings will be described in detail.

Reference numeral 1 denotes a wheel axle fixed to the vehicle body, and a bub body 3 is fitted into a bearing 2 attached to the axially outer side of the wheel axle 1, so that it can rotate around the wheel axle 1.

Reference numeral 4 denotes an iron bub drum whose axially negative side is open, and is fitted and fixed to the bub body 3.

The inner ends of spokes 5 and 6 are fixed to the flange 3a of the bub body 3 and the flange 4a of the iron bub drum 4.

As shown in FIG. 3, numeral 7 is an anisotropic arc-shaped segmented magnet piece made by molding an ordinary ferrite magnet anisotropically in the N and S directions in a parallel magnetic field, with both ends having an oblique shape 7a on the inner circumferential side.

The five anisotropic arc-shaped segmented magnet pieces 7 are disposed in an annular manner along the inner peripheral surface of the iron bab drum 4 and bonded with adhesive to form an annular magnet.

A gap portion 8 is formed on the inner peripheral side of the abutting portion of the adjacent anisotropic arc-shaped divided magnet pieces 7.

A non-metallic ring 10 is brought into contact with this gap 8 and the axially outer surface of the iron bub drum 4, and screw holes 10a provided at regular intervals in the non-metallic ring 10 are aligned with the gap 8.

A non-metallic collar 9 is disposed between the inner surface of the axial side of the iron hub drum 4 and the axial inner surface of the annular magnet, and a hole 4 is provided in the axial side of the iron hub drum 4 that matches the screw hole 10a.
b, and the screw 11 is inserted into the hole 4b, the collar 9. It is passed through the cavity 8, and its tip is screwed into the screw hole 10a, thereby fixing the metal bub drum 4, the non-metallic collar 9, and the annular magnet together.

The inner peripheral surface of the annular magnet is sequentially polarized with N and S poles.

12 is a plate fixed to the wheel axle 1 with a nut 13, which covers the axially open part of the iron bub drum 4;
A coil 14 is fixed to the inner surface in the axial direction and is placed facing the inner surface of the annular magnet with a slight gap therebetween.

According to the present invention, the annular magnet is divided into multiple pieces, each of which can be easily anisotropic in a normal parallel magnetic field, and the assembled annular magnets can be made radially anisotropic, so that the magnetic flux directed outward in the radial direction is made of iron. The magnetic flux of each polarization absorbed by the bubble drum becomes highly dense and acts on the coil, making it possible not only to obtain a large output with a small size, but also to increase the gap between the coil and the magnet to a certain extent without causing any difference in the approximately radial direction. Since it is oriented, it does not reduce the power generation capacity, and since high precision is not required, the processing cost is low. Since the iron bub drum and the annular magnet are fixed together by screwing them into the threaded holes of this non-ferrous ring through the outside surface of the side, assembly is extremely simple. This has the practical effect of being able to be manufactured at an extremely low cost as a whole.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a partially cutaway front view, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Fig. 3 is an anisotropic arc-shaped segmented magnet piece. It is an explanatory view at the time of molding. DESCRIPTION OF SYMBOLS 1...Wheel axle, 3...Bub drum body, 4...Iron bab drum, 7...Anisotropic arc-shaped segmented magnet piece, 8... ...Gap, 9
...Non-metal collar, 10...Non-metal ring, 11...Screw, 12...Coil.

Claims (1)

[Scope of utility model registration request] A plurality of anisotropic arc-shaped segmented magnet pieces are arranged in an annular manner along the inner circumferential surface of an iron bab drum that is rotatably pivoted on the wheel shaft and is open on the axial side. A gap is formed on the inner circumferential side of the abutting part of the split magnet piece, a non-metallic ring is brought into contact with the outer surface in the axial direction of the annular magnet, and screw holes provided at regular intervals in the non-metallic collar are formed in the gap. A non-metallic collar is arranged between the axially inner surface of the iron bub drum and the inner surface of the axial side of the annular magnet, and a hole that matches the screw hole is provided in the axial side of the iron bub drum. Insert a screw into the hole, collar, or cavity from the outer surface of the direction side, screw the tip of the screw into the screw hole of the nonmetallic ring, fix the iron bub drum, nonmetallic collar, and annular magnet together, and then A bicycle power generation device in which the inner circumferential surface of a magnet is polarized with S and N poles in sequence, and a coil is inserted inside.