JP2825767B2 - Method and structure for correcting multi-stage sprocket wheel of bicycle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a structure for correcting a multi-stage sprocket wheel of a bicycle.
In particular, it relates to a type of bicycle multi-stage sprocket wheel that enhances chain shift efficiency.

[0002]

2. Description of the Related Art Conventionally, the following hypothesis is mainly given to the design of a chain shift between large and small sprocket wheels. That is, when shifting between large and small sprocket wheels, the distance between the center of the separation roller and the shift roller is set to an integral multiple of the distance of the chain node. Make This is disclosed in U.S. Pat. Nos. 4,889,521 and 4,26.
No. 8,259. Based on the above hypothesis, modifications are made to the side surfaces of each tooth of the sprocket wheel for the purpose of chain guidance.

However, in practice, the chain is guided by the chain guide from the small sprocket wheel to the large sprocket wheel, and when shifting, first contacts the side surface of the large sprocket wheel, thereby causing the joint angle between the chain nodes. (Articular angle), and the chain between the release roller and the shift roller is not straight. Naturally, the center distance between these two rollers is not an integral multiple of the chain joint distance. Thus, the above-mentioned hypothesis and application to the shift operation of the conventional technique were also inaccurate.

[0004]

SUMMARY OF THE INVENTION The present invention primarily uses a type of precise shifting scheme to determine the relative phase angles of large and small sprocket wheels and to make the necessary modifications to the sprocket wheels, An object of the present invention is to provide a method and a structure for correcting a multi-stage sprocket wheel of a bicycle, which enhances the chain shift efficiency.

[0005]

SUMMARY OF THE INVENTION In order to overcome the fact that incorrect assumptions have led to inaccurate applications over the prior art shift operations, the present invention provides a method for pivoting rollers and large and small sprocket wheels. We propose the idea of adjusting the relative phase angle.

At the time of shifting, during the process in which the chain guided by the chain guide travels from the small sprocket wheel to the large sprocket wheel, the pin of the pivot roller or the pin link plate outside the pivot roller first contacts the side surface of the large sprocket wheel. The effect of this pin is analogous to a pivot, forming a joint angle between the chain node before and after the pivot roller.

Further, the chain is hung on the large sprocket wheel by the guide of the chain guide. At this time, the roller and the chain node that first engage the teeth are referred to as a shift roller and a shift chain node, respectively. The pivot roller is a roller immediately before the shift roller. Thus, the joint angle formed between the chain nodes before and after the pivot roller divides the chain between the shift roller and the release roller into two straight lines at the pivot roller.

Next, the release roller is located between the two teeth of the small sprocket wheel, and the shift roller is located between the two teeth of the large sprocket wheel. When the positions of these two rollers are known, they are simultaneously large and small. , Ie, the relative phase angles of the large and small sprocket wheels.

For this reason, the design for the shift operation of the present invention is based on the difference in the number of teeth of the large and small sprocket wheels and the size thereof, and selects the release roller and the shift roller which is separated from the release roller by an appropriate number of chain nodes. . At this time, one roller before the shift roller and the first outer chain node thereafter are referred to as a pivot roller and a shift chain node, respectively.

As described above, by designating several key rollers and a chain joint, it is possible to adjust the geometric relationship between the shift operation and the position of the separation roller and the shift roller according to the necessity of the shift operation. The relative phase angle of the wheel can be determined.

The above-described key roller and chain joint designation method is divided into a standard shift point tooth profile and a similar shift point tooth profile from the design step.

The method of designing the standard shift point tooth profile specifies the relative positions of the release roller on the small sprocket wheel and the relative positions of the shift roller and the pivot roller on the large sprocket wheel, and specifies the joint angle of the pivot roller and the sprocket wheel. The relative phase angle between them is adjusted so that the forces are balanced at the chain and the joint angles are all within the chain manufacturing rules. At this time, one straight line is formed between the pivot roller, the shift roller, and the separation roller. In this way, the correction amount of the standard shift point tooth profile side surface is determined.

On the other hand, in another similar shift point tooth profile designing method, first, the positions of the separation roller and the shift roller and the phase angle between the large and small sprocket wheels are specified, and the position of the pivot roller and the relative joint angle thereof are adjusted. The relative position of the pivot roller with respect to the separation roller is within the included angle range formed by each of the front and rear teeth (that is, within the range of 360 ° / N, where N is the number of teeth of the small sprocket wheel). And the pivot roller is pressed against the working side of the large sprocket wheel tooth profile, and the height of the working side of the tooth profile against which the pivot roller is pressed is adjusted, thereby adjusting the equilibrium state of the chain force.
In this way, the correction amount of the tooth profile side surface of the similar shift point is determined.

The tooth profile designed using the method of the present invention, whether it is a standard shift point tooth profile or a similar shift point tooth profile, can be accurately shifted with a shift roller, so that the shift operation can be performed. It goes smoothly.

Another use of the present invention is in accordance with the inferior chain characteristics, for example, when the angle at which the chain is bent is too small or too large, or when the shape of the pin link plate of the chain is poor. ,
Utilizing the method of designing a similar shift point tooth profile of the present invention, the amount of side profile correction is slightly reduced within a reasonable range so that the designed tooth profile balances between shift efficiency and tooth profile strength. I do.

In addition, in order to ensure that the pivot roller and its pin operate in accordance with the originally designed system, the pivot roller pin and its pin link plate of the large sprocket wheel at the time of shifting come into contact with each other. The correction is advanced to obtain the effect of positioning. The modification of this sprocket wheel is to use the chain as a cutting tool,
This completes the modification of the sprocket wheel by removing the interfering parts of the large and small sprocket wheel teeth and the designed chain motion path. By the same principle, the chain is guided by the small sprocket wheel, and the chain moves smoothly and accurately by modifying the teeth of the large and small sprocket wheels passing on the path to the large sprocket wheel, and the shift operation To complete.

[0017]

The present invention utilizes an accurate shift mode, determines the relative phase angles of large and small sprocket wheels, and makes necessary modifications to the sprocket wheels to increase the chain shift efficiency and increase the shift point. In addition, the time required for shifting and the noise generated are reduced, and the comfort of using the bicycle is increased.

[0018]

FIG. 1 is a diagram illustrating the operation of a system according to an embodiment of the present invention. The present invention relates to at least one large sprocket wheel (2), a smaller smaller sprocket wheel (3), and a chain which engages on these two sprocket wheels and is guided by a chain guide (not shown in the figure). 1).
A large number of teeth are provided on the outer circumference of the large sprocket wheel (2) and the small sprocket wheel (3), and the number of teeth of the large sprocket wheel (2) is determined by the number of teeth of the small sprocket wheel (3). More are provided. The chain guide is provided on the left side of the chain (1) shown in FIG. 1, and guides the chain (1) from the plane of the small sprocket wheel (3) to the plane of the large sprocket wheel (2) by a three-degree space movement. I do. At this time, large sprocket wheel (2), small sprocket wheel (3)
Rotates correspondingly about its central axis, and the chain nodes of the chain (1) mesh with each other in the order of the large sprocket wheel (2) and the small sprocket wheel (3). However, for the convenience of illustration, FIG. 1 uses the principle of inversion to fix the sprocket wheel, so that the chain guide relatively moves around the center axis of the sprocket wheel and simultaneously moves the chain (1). Guide the small sprocket wheel (3) plane to the large sprocket wheel (2) plane.

When the shifting operation starts, the chain guide moves from the plane where the small sprocket wheel (3) is located to the plane where the large sprocket wheel (2) is located. Meanwhile, the chain located between the chain guide and the small sprocket wheel (3) is driven to skew obliquely (FIG. 2).
As shown). The pin or other plate of one roller contacts the side of the large sprocket wheel (2) and stops, forming this roller as a pivot roller (10). At this time, if the conditions of the large sprocket wheel (2) and the small sprocket wheel (3) are satisfied, for example, the relative angle difference between the large sprocket wheel (2) and the small sprocket wheel (3), and the sprocket wheel When the tooth side correction situation and the like are combined together, under the drive of the chain guide and the sprocket wheel, the chain behind the pivot roller (10) rotates relatively to the pivot roller pin (11), and becomes large. Engage with sprocket wheel (2). Of these, first, the so-called shift roller (12) and shift chain node (13) mesh with the large sprocket wheel (2), and the first meshing tooth is the shift tooth (20), as shown in FIG. Then, the chain (1) is smoothly engaged with the large sprocket wheel (2), and a shift state is established.

In order to shift the chain smoothly from the small sprocket wheel (3) to the large sprocket wheel (2), the relative phase angles of the large sprocket wheel (2) and the small sprocket wheel (3) are appropriately designed. There is a need. The process of the design according to the invention consists in that the chain guide makes the chain (1) a large sprocket wheel (2).
Considering the action of the pivot roller (10) when guiding to a flat surface, the release roller (14) and the shift roller (12)
(Ie, the shift chain joint (13) and the pivot roller (10) are determined at this time), and then the large sprocket wheel (2) and the small sprocket wheel (3)
The size and shift position need to adjust the geometric relationship between these rollers and the chain node. Chain (1)
The relative phase angle between the large sprocket wheel (2) and the small sprocket wheel (3) can be obtained from the meshing relationship between the roller and the large sprocket wheel (2) and the small sprocket wheel (3).

There are two methods of specifying the roller and the chain joint of the chain described above, namely, a standard shift point tooth profile and a similar shift point tooth profile. The design method of the standard shift point tooth profile specifies the position of the release roller (14) relative to the small sprocket wheel (3) and the position of the shift roller (12) and the pivot roller (10) relative to the large sprocket wheel (2). And
The closing angle of the pivot roller (10) and the relative phase angle between the large sprocket wheel (2) and the small sprocket wheel (3) are adjusted so that the forces are balanced at the chain (1) and win. All closing angles shall be within the chain manufacturing standards. At this time, the pivot roller (10) and the shift roller (1)
2), and one straight line is formed between the separation roller (14), and thus the standard shift point tooth profile side surface correction amount can be determined. On the other hand, in the similar shift point, first, the positions of the separation roller (14) and the shift roller (12) and the phase angle between the large sprocket wheel (2) and the small sprocket wheel (3) are designated, and the position of the pivot roller (10) is specified. And adjusting the relative closing angle thereof so that the position of the pivot roller (10) is opposed to the angle between the separation roller (14) and the included angle formed by each one tooth before and after (i.e., 360). ° / N, where N is the number of teeth on the small sprocket wheel). In addition, the pivot roller (10) is pressed against the work area of the large sprocket wheel (2) tooth profile, and the height of the tooth work area on which the pivot roller (10) is pressed is adjusted, thereby adjusting the force balance of the chain. In this way, the tooth profile side correction amount of the similar shift point is determined.

In order to ensure that the chain (1) meshes with the large sprocket wheel (2) at the shift teeth (20), the large and small sprocket wheels (2), (3) near the shift teeth (20). The side surface of each tooth is necessarily modified to have the shape shown in FIG. In particular, a pivot roller pin (11) and its outer roller plate (15);
The point of contact with the large sprocket wheel (2) is used as a support for the pivot by modification, the chain (1) performs a shift operation according to the design method, and the above-described modification of the sprocket wheel uses the chain (1) as a cutting tool. 4, the portions of the motion paths of the large and small sprocket wheels (2) and (3) and the chain (1) that interfere with each other, that is, the deleted portions (21), (22), (23), and ( 24) and (3)
0), (31) etc., of which the deleted part (24) is
The modified portion of the pivot roller (10), and the deleted portion (31) is the modified portion of the release roller (14).

The tooth profile correction described above is provided for controlling and accurately controlling the position of the pivot roller except for the portion 24a, and all the portions are corrections for the next necessary tooth profile. Enlargement or molding is performed as required in manufacturing. The modification of 24a is in particular a support area for the pivot roller. Thus, a typical tooth profile correction is a lateral correction of two consecutive teeth counting from the position of the release roller on the small sprocket wheel. On the large sprocket wheel, there is a lateral correction of three consecutive teeth counting from where the pivot roller is, of which, in particular, is more precisely controlled by the pivot roller support.

The above-described embodiment is a design of a multi-stage sprocket wheel, in which a shift above it is guided by a chain guide, and the present invention is applied to a rear transmission of a rear wheel to perform a chain shift operation. The chain guide forms a rear transmission. When the sail is applied to a front sprocket wheel, the chain guide is a front transmission, and the chain bounce plate guides the chain shift operation. .

As shown in FIG. 5, in order to shift the chain smoothly from the small sprocket wheel (3) to the large sprocket wheel (2), the relative phase angle β between the large and small sprocket wheels is appropriately designed. And the relative phase angle β is determined based on the first correction method described above, which is as follows:

Chain (1) when there is no guide for derailer
When the gears are guided from the plane of the small sprocket wheel (3) to the plane of the large sprocket wheel (2), the shift roller (12) moves the large sprocket wheel (2).
At a position close to the periphery of the chain, at this time the chain (1)
First touches the side of the large sprocket wheel (2),
One release roller (14) is a roller that first disengages with the small sprocket wheel (3), and one pivot roller (10) is a roller that can contact the side surface of the large sprocket wheel (2). Initially, thereafter, any relationship between each roller and each chain node described above is adjusted in light of the shift position of the differently sized large sprocket wheel (2) and small sprocket wheel (3), and the large sprocket wheel ( The relative phase angle between 2) and the small sprocket wheel (3) is determined by the vector of engagement between the shift roller (12) and the large sprocket wheel (2) and then further adjusting the position of the pivot roller (10). And thus serve to reduce the slight amount of the correction. At the same time, the chain can be kept stretched.

The relative phase angle β is for establishing and fixing the first shift tooth in the light of the above-described first correction method, and when the shift position is reached, the correction of the tooth shape is not possible. 2 It is based on the modified method. In the second correction method, first, the position of the separation roller (14) and the opposing phase angle β are selected, and then the positions of the pivot roller (10) and the shift roller (12) are adjusted to correct the teeth. The chain (1) is held in a stretched state at the same time, and the included angle 離 formed by the separation roller (12) and the pivot roller (10) is in the range of 360 ° / N, where N is The number of teeth of the small sprocket wheel (3) is displayed, and when the shift roller (12) satisfies the above-described conditions in accordance with the contact of the teeth of the large sprocket wheel (2) with the deleted portion, each tooth shifts. It becomes incompatible for a tooth, after which the next possible shifted tooth is immediately checked according to the second modification described above.

[0028]

The present invention can increase the shifting efficiency of the small sprocket wheel and chain and increase the comfort of using the bicycle.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the operation of the system of the present invention.

FIG. 2 is a perspective view showing a method of designating a roller and a chain node of a chain at a start stage of a shift operation according to the present invention.

FIG. 3 is a perspective view showing a state in which the chain of the present invention meshes with the rear portion of the large sprocket wheel.

FIG. 4 is a perspective view showing a state where each tooth of the large and small sprocket wheels near the shift teeth of the present invention is corrected.

FIG. 5 is a side view showing a first correction method and a second correction method of the present invention.

[Explanation of symbols]

(1) Chain (10) Axis roller (11) Axis roller pin (12) Shift roller (13) Shift chain node (14) Release roller (15) Pin link plate (2) Large sprocket wheel (20) Shift tooth (21) Deleted part (22) Deleted part (23) Deleted part (24) Deleted part (3) Small sprocket wheel (30) Deleted part (31) Deleted part

Continuation of the front page (72) Inventor Tsai Chung, No.2, 86 Street, Jiangong 1-ro, Hsinchu, Taiwan (56) References JP-A-4-303094 (JP, A) JP-A-3-248988 (JP, A) JP-A-6-115480 (JP, A) Jikken 56-3263 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B62M 9/10

Claims (3)

(57) [Claims] 1. A large sprocket wheel having a plurality of teeth on its outer periphery and at least one small sprocket wheel having a smaller number of teeth on its outer periphery than the large sprocket wheel. A wheel coupled to a chain guided to the transmission, the chain comprising a plurality of rollers connected in a row by a link plate, wherein the small sprocket wheel has at least two consecutive teeth with cut-outs on the sides; The large sprocket wheel has at least three continuous teeth having a side surface with a deleted portion corresponding to a predetermined phase angle between the large sprocket wheel and the small sprocket wheel. Shift to large sprocket wheel above A multi-stage sprocket wheel arrangement for a bicycle wherein interference between the link plate and the large sprocket wheel is prevented when the teeth of the small sprocket wheel are in a first opposing position close to the large sprocket wheel. A side surface and a first opposing side remote from the large sprocket wheel, the teeth of the large sprocket wheel having a second opposing side close to the small sprocket wheel and a second opposing side remote from the small sprocket wheel;
The first opposing side and the second opposing side oppose each other, at least two of the deleted portions of the small sprocket wheel are formed on the first dorsal side, and the deleted portion of the large sprocket wheel is formed on the second dorsal side. A multi-stage sprocket wheel arrangement for a bicycle, comprising at least two cut-outs on a side and at least one cut-out on a first opposed side. 2. The small sprocket wheel has tooth side surfaces,
When the transmission drives the chain during a gearshift operation,
The detachment roller, which is the roller that detaches first from the small sprocket wheel in the chain, is removed so that it does not rise rapidly at the time of detachment and is gradually pushed up by the removed portion of the small sprocket wheel. The multi-stage sprocket wheel device for a bicycle according to claim 1, wherein: 3. The tooth side of the large sprocket wheel
One of the sides is the roller on the chain that initially couples to the large sprocket wheel after the transmission drives the chain during a gearshifting operation and that engages the large sprocket wheel like a pivot. The multi-stage sprocket wheel device for a bicycle according to claim 1, wherein the multi-stage sprocket wheel device according to claim 1, wherein the sprocket wheel device is omitted so as to include an axially extending portion serving as a fulcrum of a shift roller.