JPS6159957B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bicycle transmission device equipped with a planetary gear mechanism in which an internal gear is engaged with a planetary gear in which a rotor is pivotally supported, and a sun gear is engaged with the planetary gear. be.

As a transmission device for a bicycle with a planetary gear mechanism like the one used here, the one described in Publication of Utility Model Publication No. 28-5710 is known, but it can only be set to high speed and low speed, and it is difficult to drive. Switching to the inside would place an unreasonable burden on the structure, cause damage due to impact, and cause operational errors, making it impractical.

In addition, it is known that a planetary gear mechanism is combined with a pump structure to control the gear ratio (see Japanese Utility Model Publication No. 18-9141), but the biggest flaw in this configuration is that the planetary gear mechanism The rotation and revolution of the gears is at its maximum, the gear noise is loud, and the transmission efficiency is low. In particular, for bicycles and other devices that are driven most often at high speeds, it is better for the transmission efficiency to be close to 100%, so this continuously variable transmission configuration can be applied directly to the bicycle transmission device. Adopting it is not practical.

Therefore, the present invention has developed a bicycle transmission system that exhibits the most efficient transmission performance at high speeds, and that can steplessly change the speed increase (increase the acceleration ratio) in proportion to the input rotational speed. The aim is to provide equipment.

For this purpose, the present invention connects a rotary pump element configured to partition a pump chamber in the rotational direction to the sun gear, and also provides an inflow between the pump chamber and its discharge side within the rotor that pivotally supports the planetary gear. forming a circulation flow path that communicates with the side, and in the circulation flow path,
It is characterized in that an orifice is provided to maintain a desired opening degree, and the rotor and internal gear are used as input/output parts.

Hereinafter, the present invention will be specifically explained based on illustrated embodiments. In the figure, reference numeral 1 denotes an internal gear integrally installed on a rear wheel 2 of the bicycle, and a plurality of, for example, three, planetary gears 3 are meshed with the internal gear 1. A rotor 5, which supports the planetary gear 3 on a shaft 4, is rotatably supported coaxially with the internal gear 1, and this structure consists of four disc-shaped housings 6, 6a, 7 and The four parts are connected and fixed to each other with screws 9 and 9a. The housing 6 has a boss portion 10,
A driven side sprocket wheel 12 of a bicycle is fitted into the boss portion 10 via a one-way clutch 11.

The planetary gears 3 are located between the housings 6 and 6a, and these planetary gears 3 are connected to the sun gear 13.
is engaged with. The boss portion of the sun gear 13 passes through the housing 6a, and the boss portion of the sun gear 13 passes through the housing 6a.
and 7, and is constructed integrally with the rotary pump element 14 disposed there (it may be constructed as a separate member and connected). The rotary pump element 14 has a disc-shaped rotating body 15 coaxial with the sun gear 13.
A plurality of slide grooves 16, for example 12 slide grooves, are formed in the radial direction, and a vane 18 is supported within the slide groove 16 in the centrifugal direction by a spring 17.
The pump chamber 19 accommodating the rotary pump element 14 has an oval shape, is equidistant to each other, and is provided with a through hole 20 through which the housing is inserted. It communicates with an oil chamber 21 formed between 7 and 8. The oil chambers that are not communicated with each other via the pump chamber 19 are communicated with each other via the orifice 22, and as a whole,
A circulation flow path is formed within the rotor 5. and,
This circulation channel is filled with control oil.

The orifice 22 forms a cylindrical circulation chamber 23 in the housing 7 that extends in a direction parallel to the axis of rotation of the rotary pump element 14.
A cylindrical adjustment element 25 that moves in the axial direction in a fluid-tight manner is screwed into the circulation chamber 23, and the adjustment element 25
An annular passage 26 is formed therein.

Further, a brake drum 27 is integrally formed on the rotor 5, a brake band 28 is wound around this, and a brake control element 29 for tensioning or loosening the brake band 28 is installed at the rear. It is pivotally supported by a triangular bracket 31 provided on a fixed shaft 30 that passes through the wheel 2 (rotatably supports the sun gear 13 and the rotary pump element 14).

In such a configuration, sprocket wheel 1
When the rotor 2 is rotated by the rotation operation of the foot pedal, the rotational force is transmitted to the rotor 5 through the one-way clutch 11. Therefore, the planetary gear 3 revolves around the internal gear 1, and the rotation at this time is transmitted to the rotary pump element 14 via the sun gear 13, and the pumping action is performed by the rotation of the pump element 14. from the oil chamber 21 to the pump chamber 19 via the port 20.
Further, control oil is caused to flow from the pump chamber 19 to the oil chamber 21 via the other port 20.

The flow resistance of the orifice 22 at this time is determined by the flow cross section set by the relative position of the passage 26 and the passage 24. For this reason, the adjustment element 25
It is necessary to carefully adjust the amount of screwing in in advance. The input applied to the rotor 5 is divided into an output for turning the rotary pump element 14 (i.e., the planetary gear 3) and an output for turning the internal gear 1 (i.e., the rear wheel 2). At the start, the running resistance on internal gear 1 is large, so rather than turning it, planetary gear 3
(In other words, the power is spent on turning the sun gear 13), but as the rotation of the planetary gear 3 increases, the flow rate per unit time flowing through the oriface 22 increases, and the flow resistance increases. When this is balanced with the initial motion resistance that causes the internal gear 1 to rotate, the ratio between the rotation of the planetary gear 3 (that is, the rotation of the sun gear 13) and the rotation of the internal gear 1 is determined. Since the circulation channels such as the oil chamber 21 and the pump chamber 19 are filled with control oil, ideally the planetary gear 3 will rotate at this rate at the moment you step on the pedal (the rotary pump element 14 has an orifice 2
2), internal gear 1
rotates. If the rotation of the planetary gear 3 is large, the amount of rotation of the internal gear 1 per one rotation of the rotor 5 becomes small, and a large reduction ratio can be obtained.

Inertial force is applied to the bicycle, and the running resistance force applied to the rear wheel 2 decreases. On the other hand, if the input applied to the foot pedal remains the same, the rotation of the planetary gear 3 (rotation of the sun gear 13) decreases. , the reduction ratio of the internal gear 1 to the rotor 5 becomes smaller, and the internal gear 1 is accelerated. This is because the resistance applied to the planetary gear 3 is the flow resistance applied to the pump element 14, and is proportional to its rotation speed, whereas the running resistance applied to the rear wheel 2 (i.e., the internal gear 1) is proportional to the acceleration. This is because they are proportional, and in short, the input to the rotor 5 is distributed where the flow resistance and the running resistance of the internal gear 1 are balanced, as described above.

As the rotation of the internal gear 1 approaches the rotation of the rotor 5, the automatic speed change in this transmission device is fixed on the high speed ratio side. That is, as an ideal value, the rotation ratio between the rotor 5 and the internal gear 1 is 1:1. If more acceleration is required, the absolute value of the rotational speed of the rotor 5 must be increased by pressing the foot pedal faster. This point is
It is no different from the transmission system of a conventional bicycle.

Even if the foot pedal is stopped, since the one-way clutch 11 is interposed between the driven sprocket wheel 12 and the rotor 5, rotation is not transmitted from the rotor 5 to the sprocket wheel 12. Moreover, when the rotor 5 is running inertia in this state, the rotor 5 tries to follow the internal gear 1 and turn. This is because flow resistance is added to make the planetary gear 3 turn, so the rotor 5 with no load starts turning by itself. Therefore, the next time you step on the pedal, power is immediately transmitted with the same feel as a normal bicycle transmission system.
Moreover, as the input for acceleration is distributed between the rotation of the planetary gear 3 and the acceleration of the internal gear 1 as described above, acceleration is performed from the low gear ratio side, so there is strong resistance to the pedal when stepping. I can't feel it.

In this embodiment, a vane type pump structure is employed as the rotary pump element, but it goes without saying that a trochoid rotor or cycloid gear pump structure may also be employed.

As mentioned above, the present invention includes a planetary gear mechanism in which a planetary gear pivotally supported by a rotor, which is an input part, is meshed with an internal gear which is an output part, and a sun gear is meshed with the planetary gear. A rotary pump element configured to partition a pump chamber in the rotational direction is connected to the sun gear, and a circulation flow path communicating with the pump chamber and its discharge side and inflow side is formed inside the rotor, Since an orifice is provided in the circulation flow path to maintain the desired opening degree, the highest transmission efficiency can be obtained when the maximum speed ratio is obtained. (increases the acceleration ratio), and can demonstrate optimal performance for the running performance of the bicycle.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing one embodiment of the present invention, FIG. 2 is a view taken along the line A-A in FIG. 1, FIG. 3 is a view taken along the line B-B in FIG. The figure is Figure 1 C-C
It is a line arrow view. 1...Internal gear, 3...Planetary gear, 4...Shaft,
5... Rotor, 13... Sun gear, 14... Rotary pump element, 15... Rotating body, 16... Slide groove, 18... Vane, 19... Pump chamber, 20...
... Entrance, 21... Oil room, 22... Orifice,
24...Port, 25...Adjustment element, 26...Annular passage.

Claims (1)

[Claims] 1. In a device equipped with a planetary gear mechanism in which a planetary gear supported by a rotor is meshed with an internal gear, and a sun gear is meshed with the planetary gear, the sun gear is configured to partition a pump chamber in the direction of rotation. A rotary pump element configured as shown in FIG. A bicycle transmission device, characterized in that the rotor and the internal gear are provided as input/output parts.