JPH09132185A - Hub dynamo for bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide cost reduction for the dynamo for a bicycle by using an iron dynamo case as a yoke which forms the magnetic circuit of a generator, and making the functions of the case serve as that of the yoke. SOLUTION: A right spoke 1 joined with the rim of the tire of a front wheel is joined with a circular flange 3 formed out of iron plate press-formed. A left spoke 2 is joined with a dynamo case 4 formed by deep-drawing the iron plate. The dynamo case 4 and a dynamo case cap 23 are the rotating side rotors of a hub dynamo. A magnet 24 is fixed on the inside of the dynamo case 4, and the iron dynamo case 4 also serves as a yoke which constitutes the magnetic circuit of the magnet. It is thus possible to reduce material cost and manufacturing cost and provide great cost reduction because of reduction in the man-hour of assembly.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a bicycle hub dynamo which is a bicycle generator.

[0002]

2. Description of the Related Art A bicycle hub dynamo in which a generator is built in a conventional bicycle hub will be described with reference to FIGS.

FIG. 3 is a front sectional view of a conventional bicycle hub dynamo, which is a dynamo case 31 for the hub dynamo.
Since it is made of aluminum, the magnetic circuit of the generator is composed of the magnet 24, the annular yoke 30, the coil 14 and the iron core 16.

FIG. 4 is a side sectional view of FIG. 3, in which the inner yoke of the aluminum dynamo case 31 has an annular yoke 30.
Is provided.

[0005]

At present, the price of bicycles is becoming more and more expensive, and the cost of products is urgently required. Also,
A bicycle generator is indispensable for avoiding dangerous lightless driving of the bicycle at night.

It is an object of the present invention to provide a bicycle hub dynamo that reduces the cost of the bicycle generator.

[0007]

According to the present invention, an iron dynamo case formed by press working of an iron plate is used in place of the conventional aluminum dynamo case, and an iron annular yoke which is a part of a conventional magnetic circuit is used. By replacing the aluminum with iron to reduce the material cost and the processing cost by removing the above-mentioned iron dynamo case from both the role of the case and the role of the yoke. It is designed to reduce the cost of the bicycle hub dynamo that is the machine.

Particularly in terms of reducing the processing cost, the conventional aluminum dynamo case is cast or forged and then cut,
Although this has been a factor in increasing the cost of the bicycle, such as by performing exterior painting, since the iron dynamo case can be manufactured by press working, there is no need for post-processing, and the present invention can significantly reduce costs.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a sectional view of a front wheel of a bicycle in which a hub dynamo, which is a bicycle generator of the present invention, is incorporated, as seen from the front. FIG. 2 is a side view of the hub dynamo which is the bicycle generator of the present invention with the dynamo case cap removed.

In these figures, the right spoke 1 connected to the tire rim of the front wheel is connected to a circular flange 3 formed by pressing an iron plate, and the left spoke 2 presses the iron plate several times. Is connected to the dynamo case 4 formed by deep drawing.

By manufacturing the dynamo case 4 by pressing as described above, compared with the conventional aluminum case, the cutting and polishing processes after molding are completely unnecessary, and the manufacturing process and the material cost can be greatly reduced. it can.

The bearing 5 is press-fitted into the central concave portion of the flange 3, and the outer liner 5a of the bearing 5 is sandwiched between the flange 3 and the dynamo case 4 and fixed by the rivet 8. The case 4 is configured so as not to fall out.

The inner liner 5 of the bearing 5
b is sandwiched between the step portion 10 of the integrated sleeve 9 and the nut 12 via the washer 11, and the bearing 5 is configured so as not to fall off the shaft 13 to which the integrated sleeve 9 is fixed.

The integral sleeve 9 is integrally formed by die casting insert molding using an aluminum material at a predetermined position of the shaft 13 which is threaded over the entire length, and is firmly formed on the shaft 13. It is fixedly held.
This integral sleeve 9 is made of hard resin and has a shaft 13 formed therein.
It is also possible to integrally mold the above.

A coil 14, a coil bobbin 15, and an iron core 16 of the stationary stator of the hub dynamo are fixed to the outer peripheral surface of the integral sleeve 9 with rivets 17. Also,
The inner liner 19b of the bearing 19 abuts on the step portion 18 of the integrated sleeve 9, and the bearing 19 is a nut 22 with a washer 20 and an insulating terminal plate provided with a terminal 21 for taking out the output of the hub dynamo. It is pinched.

Outer liner 19a of bearing 19
Is press-fitted and fixed in the central recess of a circular dynamo case cap 23 formed by pressing an iron plate. The peripheral portion of the dynamo case cap 23 is the dynamo case 4
It is press-fitted and fixed in.

The dynamo case 4 and the dynamo case cap 23 are rotors on the rotating side of the hub dynamo. A magnet 24 is fixed inside the dynamo case 4, and the iron dynamo case 4 constitutes a yoke constituting a magnetic circuit of the magnet. I also use it.

As a result, the conventional yoke becomes unnecessary, and the material cost and the number of assembling steps are reduced accordingly. Fork 2
5 is connected to the body of the bicycle, the shaft 1 with bolts 26
It is fixed to 3.

Inside the dynamo case 4, a seven-pole magnet 24 is divided into four and fixed. These form the rotating side rotor of the hub dynamo.

In the stationary stator of the hub dynamo, the coil bobbin 15 and the iron core 16 are fixed to the integral sleeve 9 by the rivets 17, and the integral sleeve 9 is fixed to the shaft 9.

The dynamo case to which the magnet 24 is fixed is rotated by the rotation of the wheels, and the magnetic field of the magnet 24 and the coil of the fixed coil bobbin 15 generate electromagnetic power to generate electricity. The magnetic circuit at this time is composed of the coil of the coil bobbin 15, the iron core 16, the magnet 24, and the iron dynamo case 4.

As described above, by using the iron dynamo case 4, the dynamo case 4 can be used both as a case and as a yoke which is a part of the magnetic circuit of the generator. The cost can be reduced and the assembly process can be simplified.

[0024]

As described above, according to the present invention, by using the iron dynamo case, the function of the case and the function of the yoke forming the magnetic circuit of the generator can be integrated.
The cost of the bicycle hub dynamo can be reduced by reducing the number of parts and the number of manufacturing and assembling steps as compared with the conventional aluminum dynamo case.

Further, since the dynamo case is made of iron, the dynamo case can be easily manufactured by press working, so that the material cost and the manufacturing cost can be reduced, and further the assembly man-hours can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a bicycle hub dynamo according to the present invention.

FIG. 2 is a side view of the bicycle hub dynamo according to the present invention with the dynamo case cap removed.

FIG. 3 is a front sectional view of a conventional bicycle hub dynamo.

FIG. 4 is a side view of a conventional bicycle hub dynamo with a dynamo case cap removed.

[Explanation of symbols]

 3 Flange 4 Iron Dynamo Case 14 Coil 15 Coil Bobbin 16 Iron Core 24 Magnet

Claims (1)

[Claims] 1. In a bicycle hub dynamo having a generator built in a bicycle hub, an iron dynamo case is used as a yoke constituting a magnetic circuit of the generator, and the iron dynamo case serves as a case and a role of the yoke. A hub dynamo for bicycles, which is characterized by being used as both.