JPH0688546B2 - Bicycle generator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a power generator built into a bicycle hub.

(Prior Art) In general, as a bicycle power generator, an exterior type in which a generator separate from a bicycle body is attached to the bicycle body is often used.

This external generator drives the generator by pressing the roller of the generator against the side surface or the outer periphery of the tire and frictionally transmitting from the tire to the roller of the generator.

However, in this type of generator, the mechanical conduction efficiency of frictional conduction was poor, and although the amount of power generation was small, the rotational load of the pedal was felt quite heavy.

The efficiency of the generator is greatly affected by the accuracy of mounting the generator on the vehicle body, the deflection of the wheels, and the like.

Also, because it is frictionally conductive, when the tire gets wet,
As a result of the friction coefficient remarkably lowering and slipping, efficiency may be further deteriorated and power generation may not be possible.

In addition, there is a drawback that only the contact surface of the tire with the roller is partially worn.

In order to eliminate these drawbacks, the techniques disclosed in Japanese Utility Model Laid-Open Nos. 58-188385 and 57-12384 have been devised.

(Problems to be Solved by the Invention) In an induction generator using a coil and a permanent magnet, the electromotive force thereof is generated in proportion to (number of coil turns × flux density × rotational week speed).

In the conventional exterior type, by rotating a roller (diameter 20 mm) with a tire (diameter 660 mm), the rotor speed is increased to approximately 33 times the wheel rotation, thereby increasing the peripheral speed of the rotor. .

Also, since the number of poles of this type of generator is usually eight,
The number of poles when the wheel makes one rotation is about 264 poles (8 poles x 33), so smooth rotation with almost no pulsation is obtained.

However, in the case where the generator is a hub built-in type as in the above-mentioned conventional technique, the rotation of the rotor is the same as the rotation of the wheels, and the peripheral speed of the rotor is significantly reduced as compared with the case of the exterior type. .

That is, in order to obtain an electromotive force equivalent to that of the external generator, it is necessary that the value of (coil winding number × magnetic flux density × rotational peripheral speed) be equal to that of the external generator.

For this reason, in the above-mentioned Japanese Utility Model No. 58-188385, the outer diameter of the rotor is increased, but since a sufficient peripheral speed cannot be obtained, the magnet is strengthened and the number of turns of the coil is further increased. The same electromotive force is finally obtained by increasing.

However, even though the outer diameter is increased, the maximum number of magnets that can be arranged on the circumference is 24 to 36, which is significantly smaller than the conventional 264 poles, which causes pulsation in rotation. There is a problem that it occurs.

Further, in the above-mentioned Japanese Utility Model Laid-Open No. 57-12384, the rotation of the hub is accelerated by the planetary gear mechanism, but in the case of a single-stage planetary gear train, there is a limit of about 5 times in practical use. Therefore, in this case as well, a sufficient peripheral speed of the rotor cannot be obtained, so by increasing the outer diameter of the rotor, strengthening the magnet, and increasing the number of coil turns,
It is necessary to obtain the same electromotive force as the external generator.

Further, since the coil of the above-mentioned conventional device has a cylindrical shape arranged on the circumference, the maximum number is about six.

That is, since the number of poles for one rotation of the wheel in this case is about 30 poles (6 poles × 5), it is conceivable that pulsation occurs in the rotation as in the previous example.

Therefore, both of the above-mentioned two prior arts require a large-diameter rotor and cannot be made compact.

Moreover, since the number of poles for one rotation of the wheel is not sufficient, there is a problem that smooth rotation cannot be obtained.

(Means for Solving the Problems) In order to solve the above-mentioned problems, in the present invention, an axle having a hollow cylinder in the middle is fixed to a frame of a bicycle, and a hub body of a wheel is freely rotatable with respect to the axle. And a generator coil body is fixedly provided in the hollow cylinder of the axle, and a rotor integrally formed with a magnet and a second sun gear is rotatably provided. 1. A planetary carrier that is integrally formed with the first sun gear is rotatably provided, a first internal gear is formed on the inner peripheral portion of the hub body, and the first internal gear and the first sun gear mesh with each other. A first planetary gear that is pivotally supported on the axle, a second internal gear is provided inside the hollow cylinder of the axle, and a second internal gear that meshes with the second sun gear. A planetary gear is pivotally supported on the planet Kiriya to construct a bicycle power generator. To do.

(Operation) Since the device of the present invention is configured as described above, it is first configured by the first internal gear of the hub body, the first planetary gear pivotally supported on the axle, and the first sun gear integrated with the planet carrier. The rotation speed of the hub body is increased by the first stage planetary gear train to be transmitted to the planet carrier, and further, the second internal gear formed in the hollow cylinder and the planet carrier are pivotally supported by the planet carrier. The rotation speed of the planet carrier is further increased and transmitted to the rotor by the second stage planetary gear train composed of the two planet gears and the second sun gear of the rotor.

That is, the peripheral speed of the rotor that is equivalent to that of the exterior type can be obtained by the two speed increases.

Therefore, according to the present invention, it is possible to generate an electromotive force equivalent to that of the exterior type without strengthening the magnet, increasing the number of turns of the power generation coil, and increasing the outer diameter of the rotor. .

Also, since the number of poles for one rotation of the wheel is almost the same as the exterior type,
Smooth rotation with almost no pulsation can be obtained.

(Example) Hereinafter, the Example of this invention is described about drawing. 1 in the figure
Is a front hawk which is a part of a bicycle frame, and 2 is an axle which is hung across the ends of the left and right front forks 1 and fixed by nuts 3, respectively.

This axle 2 is provided with a hollow cylinder 2a in the middle,
Form a screw 2b on the outer periphery of the left end in FIG. 1 of 2a,
While screwing with the screw 2b, the left lid 2c having a boss portion projecting in the center is screwed with the hollow cylinder 2a via the screw 2b.
The base of the screw rod 2d is screwed into the boss of the left lid 2c.

In addition, a screw is attached to the inner circumference of the right end of the hollow cylinder 2a in FIG.
2e is formed and screwed with this screw 2e, and a right side cover 2f having a boss projecting in the center is formed into a hollow cylinder through the screw 2e.
2a is screwed together, and the base of the screw rod 2g is screwed into the boss of the right lid 2f.

That is, the axle 2 includes a hollow cylinder 2a, left and right side lids 2c, 2f,
And the threaded rods 2d and 2g are joined together.

In the axle 2 thus formed, as shown in FIG. 1, the left and right screw rods 2d and 2g are engaged with the grooves at the lower end of the front fork 1 and fixed by the nut 3 and the like.

Reference numeral 4 denotes a hub body for the front wheel of the bicycle. The hub body 4 is formed into a hollow cylindrical shape with one end (the left end in FIG. 1) opened, and the side cover body 5 is screwed to the open end. Bearing 6
It is rotatably provided on the axle 2 via. The open end side of the hub body 4 is expanded in diameter to form a large-diameter portion 4a, and a first internal gear 4b is formed inside thereof. Incidentally, 7 are wheel spokes attached to the hub body 4, respectively.

Further, as shown in detail in FIG. 3, the conductor 8b is wound in the groove of the grooved ring 8a to form the coil 8, and then the strip-shaped magnetic pole pieces 9a are respectively arranged at positions where the outer circumference of the cylinder is divided into four. The first armature 9 is integrally formed by connecting the four magnetic pole pieces 9a to the cylindrical portion 9b of the subtotal, and the cylindrical portion 9b of the first armature 9 is formed in the central hole of the coil 8. A cylindrical portion 10a which is inserted into the inside of 8c and encloses a cylindrical portion 9b projecting from the center hole 8c; And the second armature 10 is integrally formed, and the second armature 10
Is fitted to the above-mentioned combined body of the coil 8 and the first armature 9 to integrally form the generator coil body 11 as shown in FIG. Reference numeral 12 is a lead wire drawn from the coil 8.

Then, as shown in FIG. 1, the generator coil body 11 configured as described above is inserted into the hollow cylinder 2a of the axle 2 at the right end in the figure and fixed, and the lead wire 12 thereof is attached to the right lid of the axle 2. The body 2f is taken out through the hole 2h and the groove 2i.

Further, the magnet 13a and the second sun gear 13b are integrally formed with the rotor 13 via the shaft 13c, and the magnet 13a of the rotor 13 corresponds to the magnetic pole pieces 9a and 10b of the power generating coil body 11. Thus, it is rotatably provided in the hollow cylinder 2a of the axle 2.

That is, the shaft end 13d on the left side of the shaft 13c of the rotor 13 in FIG. 1 is rotatably supported by the bearing metal 14 provided on the left lid 2c of the axle 2, and the shaft end 13e on the right side of the shaft 13c is rotatably supported. Bearing metal 15 provided on the right side lid 2f of the axle 2.
It is rotatably supported by.

Then, a ring-shaped second internal gear 16 is fixedly provided to the axle 2 on the inner peripheral portion of the axle 2 facing the second sun gear 13b integral with the rotor 13.

Further, the first sun gear 17a and the disk-shaped planet carrier 17 are integrally formed, and the planet carrier 17 is rotated to 13c between the second sun gear 13b integrated with the rotor 13 and the left lid 2c. Three first planetary gears 18 (see FIG. 4) which are freely provided and mesh with the first internal gear 4b and the first sun gear 17a, respectively, are provided in the left side cover 2c of the axle 2 with a shaft 19 And two rotatably provided via the second internal gear 16 and the second sun gear 13b, respectively, and three second planetary gears 20 (see FIG. 5) that are engaged with the planetary carrier 17. Each of the two 21 is pivotally supported to form a bicycle power generator.

Next, the operation of the device of the present invention configured as described above will be described.

When this bicycle runs, the hub body 4 formed integrally with the wheels rotates in the direction of arrow A in FIG. In this case, since the axle 2 is fixed, the first planetary gear 18 rotates about the axis 19 in the direction of arrow B. This first planetary gear
By the rotation of 18 in the direction of arrow B, the first sun gear 17a meshing with the first planetary gear 18 is accelerated and rotated in the direction of arrow C in FIG.

In the present embodiment, since the number of teeth of the first internal gear 4b is 75T and the number of teeth of the first sun gear 17a is 15T, the planet carrier 17
The rotation of the hub body 4 is 75 ÷ 15 = 5.
Double speedup.

Further, the planet carrier 17 integrated with the first sun gear 17a is indicated by an arrow C.
If it rotates in the direction of arrow C, the shaft 21 will also move in the direction of arrow C as shown in FIG.
Rotate in the direction of. In this case, since the second internal gear 16 is fixed, the second planetary gear 20 revolves in the direction of arrow C and rotates in the direction of arrow D. Therefore, the second sun gear 13b meshing with this rotates at an increased speed in the direction of arrow E.

In the present embodiment, the number of teeth of the second internal gear 16 is 44T, the number of teeth of the second sun gear 13b is 10T, and (44 + 10) ÷ 10 = 5.4. Therefore, the rotation of the second sun gear 13b is Of planet carrier 17
5.4 times speedup.

That is, according to the apparatus of this embodiment, the first stage planetary gear train and the second stage planetary gear train 27 times (5 × 5.
The speed increase ratio of 4) is obtained.

(Effect of the invention) As described above, according to the present invention, since the rotor 13 provided in the bicycle hub body 4 is accelerated by the two-stage planetary gear train, the rotor 13 is, for example, as in this embodiment, It rotates at 27 times the speed of the wheel, and it is possible to obtain the same peripheral speed as the exterior type.

That is, according to the present invention, it is possible to generate an electromotive force equivalent to that of the exterior type without strengthening the magnet 13a or increasing the number of turns of the power generation coil 8.

Therefore, it is possible to use a magnet and a generator coil of the same size as those of the exterior type, without requiring specially designed parts such as a conventional built-in hub type generator. Can have a small diameter.

Also, since the number of poles for one rotation of the wheel is almost the same as the exterior type,
Smooth rotation with almost no pulsation can be obtained.

Further, because of gear conduction, stable and high efficiency can be maintained without being affected by water wetting of the friction surface and mounting accuracy with respect to the wheels unlike the exterior type.

Therefore, according to the present invention, it is possible to provide an excellent effect that it is possible to provide a small-sized hub-embedded power generator that has power generation performance equivalent to that of the conventional one, is efficient, and has a good appearance.

[Brief description of drawings]

 FIG. 1 is a sectional view of an embodiment of the device of the present invention, FIG. 2 is a perspective view of a power generation coil body, FIG. 3 is an exploded perspective view of the power generation coil body, and FIG. Explanatory drawing and FIG. 5 are operation explanatory views of the planetary gear train of the second stage. 1 ... Front hawk, 2 ... Axle 2a ... Hollow cylinder, 2c ... Left lid 2d ... Screw rod, 2f ... Right lid 2g ... Screw rod, 4 ... Hub 4b ... 1st Internal gear, 5 ... Side lid 8 ... Coil, 9 ... First armature 10 ... Second armature, 11 ... Generator coil body 13 ... Rotor, 13a ... Magnet 13b. 2 sun gear, 16 ... second internal gear 17 ... planet carrier, 17a ... first sun gear 18 ... first planet gear, 20 ... second planet gear

Claims (1)

[Claims] 1. An axle having a hollow cylinder in the middle is fixed to a bicycle frame, a hub body of a wheel is rotatably fitted to the axle, and a generator coil body is fixed in the hollow cylinder of the axle. And a rotor integrally formed with a magnet and a second sun gear is rotatably provided, and a planet carrier integrally formed with the first sun gear is rotatably provided on a shaft of the rotor. A first internal gear is formed on an inner peripheral portion of the hub body, and a first planetary gear that meshes with the first internal gear and the first sun gear is pivotally supported on the axle, and the axle is provided. The second internal gear is provided inside the hollow cylinder of
A second gear that meshes with the internal gear and the second sun gear, respectively.
A bicycle generator comprising a planetary gear pivotally supported on the planet carrier.