TWI705027B - Rear derailleur having buffer structure - Google Patents

Abstract

A rear derailleur having buffer structure provided on a frame includes an upper base, a lower base, a chain retention device, and a buffer structure. The upper base is provided on the frame. The upper base is provided on the upper base. The chain retention device is pivoted on the lower base. The buffer structure includes a slot that is provided on the lower base, a blocker that is provided on the slot, and a post that one end connects to the chain retention device the other end extends to the slot, wherein the blocker has an arm, which has a flexible convex. When the chain retention device pivots, the post moves in the slot. When the post crosses the convex of the blocker, the post makes the blocker deforming. And then the blocker provides a resistance for the post.

Description

Transmission with buffer structure

The present invention relates to the technical field of a rear derailleur, in particular to a rear derailleur with a buffer structure.

In the process of shifting the bicycle, the user pulls the shift lever to drive a transmission to shift. Generally, the rear derailleur has an upper main seat and a lower main seat, which are respectively connected to a frame and a chain guide. The lower main seat further has A groove, a cylinder is installed in the chain guide, wherein the cylinder is installed in the groove, so as to provide the chain guide to slide in the groove through the cylinder during shifting, and to give the cylinder A resistance to maintain the tension of the chain.

Generally, when the gear is shifted according to the conventional above-mentioned structure, when the small chainring is in motion, the tension of the chain will be weaker because the chain meshes with the chainring less. The column will slide in the groove while being affected by the resistance, so that the chain maintains its tension and is not easy to fall off.

However, in the conventional practice, when the larger chainring moves, the tension of the chain will be stronger because there are more places where the chain meshes with the chainring. However, the column still slides in the groove and is affected by its resistance, which may cause improper transmission of the rear derailleur. In severe cases, the chain may even drop.

The main seat structure under the above conventional transmissions may cause the chain to fall off, and it may even cause unpleasant riding on the user.

The object of the present invention is to provide a cushioning structure for the main seat under the rear derailleur, which can increase the resistance in a predetermined interval to maintain the tension of the chain.

A rear transmission with a buffer structure, mounted on a frame, includes: an upper main seat fixedly connected to the frame; a lower main seat fixedly connected to the upper main seat; a chain guide pivotally connected to the lower main seat Main seat; and a buffer structure, including a groove provided in the lower main seat, a blocking member provided in the groove, and a column connected to the chain guide at one end and extending into the groove at the other end ; Wherein, the blocking member has an arm, the arm has an elastic blocking end; when the chain guide pivots relative to the lower main seat, the column will move in the groove; when the When the column abuts or even crosses the blocking end of the blocking member, the blocking member will be deformed, and the blocking member will provide a resistance when the column moves.

In an embodiment, the lower main seat is further provided with a fixing portion; the blocking member has a connecting portion, and the connecting portion is combined with the fixing portion.

In one embodiment, one of the side walls of the groove is provided with a recess, and the recess is separated from the fixing portion by a predetermined distance; the blocking member has a part abutting against the bottom end of the recess.

In one embodiment, the arm portion of the blocking member has a bent protrusion portion to form the blocking end.

In one embodiment, the blocking member further has an arm portion, and the arm portion has an elastic blocking end; the blocking ends of the two arm portions are opposite.

In one embodiment, the lower main seat is further provided with a guide groove on the bottom surface of the groove, the width of which is slightly larger than the diameter of the cylinder, and the cylinder extends into the guide groove.

In one embodiment, it further includes an adjuster, which is movably arranged on the lower main base; the adjuster has an extension arm portion with a resisting portion; when the adjuster moves, the resisting portion will Lean against different positions on the arm of the blocking member.

In an embodiment, the lower main seat has a concave portion communicating with the groove; the adjuster has a body, and the body is accommodated in the concave portion so that the adjuster can move along the concave portion; the One end of the extension arm is connected to the body, and the other end extends to the groove.

In an embodiment, the adjuster can move between a first position and a second position; one end of the concave portion is provided with a first positioning portion, and the other end is provided with a second positioning portion; the body is accommodated in the A concave portion, one end has a first positioning portion, and the other end has a second positioning portion; when the adjuster moves to the first position, the first positioning portion of the body is combined with the first positioning portion of the concave portion; When the adjuster moves to the second position, the second positioning portion of the body is combined with the second positioning portion of the concave portion.

In one embodiment, the lower main seat further has a notch so that the recess can communicate with the outside of the lower main seat through the notch; the adjuster further has an operating portion connected to one side of the body , The operating part extends out of the lower main seat from the gap.

The above method can solve the problem that the conventional buffer structure provides resistance to the chain guide in the whole area, which may result in improper use of components and shorten the short-term life, and it is more likely that the chain will fall due to improper shifting. The present invention can output resistance to the chain guide through a preset interval, and other areas may not provide resistance. In this way, the chain guide can maintain a stable tension of the chain and prolong the service life of components.

In accordance with the purpose and effect of this creation, the following is a detailed description of preferred embodiments with illustrations.

Please refer to FIG. 1, the first preferred embodiment of the present invention provides a rear derailleur 1 mounted on a frame for changing a chain 2 to different chainrings on a flywheel 3 for movement. Among them, the chainrings of the flywheel 3 are defined as the first chainring to the 8th chainring from small to large, for the sake of subsequent description. The rear derailleur 1 has an upper main seat 10, a lower main seat 20 and a chain guide 30. The upper main seat 10 is connected to the frame for fixing the rear derailleur 1. The lower main base 20 is connected to the upper main base 10 in a locking manner, and is connected to the chain guide 30 in a pivotal manner, so that the chain guide 30 can rotate freely relative to the lower main base 20.

Please refer to Figures 2 and 3, the upper main seat 10 and the chain guide 30 of the rear derailleur 1 (see Figure 1) are both conventional structures, and will not be repeated here. The main invention of the present invention The characteristic is that the lower main seat 20 has a buffer structure. The buffer structure includes a groove 21 disposed in the lower main seat 20 and a blocking member 22 disposed in the groove 21. The groove 21 is roughly fan-shaped, and its two ends are divided into a first end 211 and a second end 212. The groove 21 is further provided with a fixing portion 213, which is a hook-shaped slot, and is disposed at the first end 211 of the groove 21. In addition, a recess 214 is provided on the side wall of the groove 21, and the recess 214 is spaced from the fixing portion 213 by a predetermined distance. The blocking member 22 is a wavy metal plate with elasticity, and has an arm portion 221 and a connecting portion 222. The shape of the connecting portion 222 corresponds to the fixing portion 213. When the connecting portion 222 is combined with the fixing portion 213, the arm portion 221 is located in the groove, and a part of the arm portion 221 abuts against the recess. The bottom end of the socket 214. By the combination of the connecting portion 222 and the fixing portion 213 and the arm portion 221 abutting against the bottom end of the recess 214, the blocking member 22 is stably disposed on the lower main seat 20. The arm portion 221 of the blocking member 22 further has a blocking end 223, and the blocking end 223 is a part of the blocking member 22 that is bent to form a protrusion. The blocking end 223 is located at a predetermined position of the groove 21 so that the width of the groove 21 at the blocking end 223 is reduced.

Wherein, the buffer structure further has a column 31, one end of which is fixed to the chain guide 30, and the other end extends into the groove 21. When the chain guide 30 swings relative to the lower main base 20, the column The body 31 can move between the first end 211 and the second end 212 of the groove 21.

In this embodiment, when the rear derailleur 1 intends to convert the chain 2 from the small chainring of the flywheel 3 to the large chainring, the column 31 will move from the first end 211 of the groove 21 to the second end 212 mobile. When the chain 2 is to be converted from the fourth chainring to the fifth chainring, the column 31 will just cross the blocking end 223 of the blocking member 22.

Referring to FIGS. 3 to 5, when the column 31 abuts against the blocking end 223, the blocking end 223 will provide the column 31 with a resistance. And when the column 31 crosses the blocking end 223 of the blocking member 22, it will press the blocking end 223 to deform it. Thereby, a predetermined tension can be provided to the chain 2 so that it can be smoothly converted from the fourth gear with a smaller number of teeth to the fifth gear with a greater number of teeth without the chain falling off. Conversely, when the rear derailleur 1 intends to convert the chain 2 from the large chainring of the flywheel 3 to the small chainring, the column 31 will move from the second end 212 of the groove 21 to the first end 211. When the chain 2 intends to switch from the fifth chainring to the fourth chainring, it will also cross the blocking end 223 of the blocking member 22 to produce the same effect.

It should be pointed out here that the position of the blocking end 223 can be changed according to the number of gears of the flywheel 2 and the number of teeth. In addition, the blocking member 22 may also have a plurality of stop ends 223, so that the chain 2 can smoothly switch between the chainrings.

FIG. 6 shows a lower main base 20', a blocking member 22, and a column 31, a second preferred embodiment of the present invention. The lower main base 20' has a groove 21 and a fixing portion 213. The groove 21 also has a fan shape, and the fixing portion 213 is generally a U-shaped slot located at one end of the groove 21. The blocking member 22 is generally U-shaped with two corresponding arm portions 221, and a connecting portion 222 is formed at the bending portion. The two arm portions 221 respectively have a blocking end 223 protruding toward each other. The connecting portion 222 is inserted into the fixing portion 213 so that the two arm portions 221 are located in the groove 21 of the lower main base 20. The column 31 is located between the two arm portions 221 and moves along the groove 21. When the column 31 abuts or even crosses the second gear end 223, a resistance will also be obtained, so that the chain 2 can smoothly shift between the chain gears.

Figure 7 shows the main seat 20" under the third preferred embodiment of the present invention, which is roughly similar to the second embodiment, except that the fixing portion 213 is provided at the second end 212, and the bottom surface of the groove 21 is further provided There is a guide groove 215. The cylinder 31 passes through the groove 21 and extends into the guide groove 215. The width of the guide groove 215 is slightly larger than the diameter of the cylinder 31, which can effectively limit the lateral displacement of the cylinder 31. In order to provide a more precise implementation effect. The implementation is the same as before, so it will not be repeated here.

Please refer to FIG. 8, the rear transmission provided by the fourth preferred embodiment of the present invention includes a lower main base 20'', a blocking member 22, a cylinder 31, and an adjuster 23. The lower main seat 20''' includes a groove 21 and a recess 24. The recess 24 is located on one side of the groove 21 and communicates with the groove 21. The lower main seat 20’’’ further has a notch 25 so that the recess 24 can communicate with the outside of the lower main seat 20’’’ through the notch 25. A fixing portion 213 is provided at the junction of the concave portion 24 and the groove 21. The concave portion 24 is provided with a first positioning portion 241 at an end far away from the groove 21 and a second positioning portion 242 is provided at an end close to the groove 21. In this embodiment, the first positioning portion 241 is a recess provided on one side wall of the recess 24, and the second positioning portion 242 is a protrusion provided on the other side wall of the recess 24. There is a crack on the bump, which makes the bump elastic and can change its width after receiving external force. The blocking member 22 is similar to the blocking member 22 of the second preferred embodiment, and has two arm portions 221 and a fixing portion 222. Each arm 221 is provided with an opposite blocking end 223. One end of the column 31 is connected to the chain guide 30 (not shown), and the other end is inserted into the groove 21 and located between the two arm portions 221 of the blocking member 22. The adjuster 23 has a body part 231, two extension arm parts 232 and an operating part 233. The body 231 has a first positioning portion 2311 at one end and a second positioning portion 2312 at the other end. In this embodiment, the first positioning portion 2311 is a bump with a slit, and the second positioning portion 2312 is a notch. The two extension arm portions 232 extend outward from one end with the second positioning portion 2312, and each of the outer ends has a resisting portion 2321. The operating portion 233 is connected to one side of the body 231. The body portion 231 is accommodated in the recessed portion 24, so that the two extending arm portions 232 extend into the groove 21, and the operating portion 233 extends out of the lower main seat 20''' through the gap 25. The user can move the adjuster 23 between a first position and a second position by holding the operating portion 233.

When the adjuster 23 moves to the first position, please refer to Figure 8. The first positioning portion 2311 of the adjuster 23 is combined with the first positioning portion 241 of the lower main seat 20"' to make the adjuster 23 is positioned at the first position. At this time, the abutting portion 2321 of the two extending arm portions 232 contacts the two arm portions 221 of the blocking member 22 at a position closer to the fixing portion 213. When the adjuster 23 moves to the second position, please refer to Figure 9. The second positioning portion 2312 of the adjuster 23 is combined with the second positioning portion 242 of the lower main seat 20"' to make the adjuster 23 is positioned at the second position. At this time, the abutting portion 2321 of the two extending arm portions 232 contacts the two arm portions 221 of the blocking member 22 at a position farther from the fixing portion 213.

When the adjuster 23 moves to the second position, it has a longer force arm than in the first position (the distance between the contact point of the two abutting portions 2321 and the two arm portions 221 and the fixing portion 213 ), therefore, when the column 31 abuts or even crosses the second stop end 223 of the stopper 22, it will receive a greater resistance. In short, the adjuster 23 provides the blocking member 22 with a function of changing resistance. When the user finds that a greater resistance is required for the chain 2 to change the chainring smoothly, the adjuster 23 can be moved to the second position. If a small resistance is needed to complete the change of the chain 2 now, the adjuster 23 can be moved to the first position.

Based on the above, the present invention can provide users with a smooth riding experience, and can solve the problem that the conventional structure has a resistance on the chainring regardless of the size of the chainring. Further divide the resistance zone, so that the components can be used for their purposes, so as to extend the service life of the components. The present invention also provides an innovative idea for the industry to further develop the industry. Follow-up industrial ideas can also work in this direction and jointly provide more innovative ideas for the industry.

The above-mentioned embodiments are only illustrative of the technology and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with this technology can modify and change the above-mentioned embodiments without violating the technical principle and spirit of the present invention. Therefore, the protection scope of the present invention should be listed in the scope of patent application described later .

1: rear derailleur

2: chain

3: flywheel

10: Upper main seat

20: Lower main seat

21: Groove

211: first end

212: second end

213: Fixed part

214: Dimple

215: Guide groove

22: blocking piece

221: Arm

222: Connection part

223: Block End

23: adjuster

231: Body

2311: The first positioning part

2312: second positioning part

232: Extension arm

2321: Arrival

233: Operation Department

24: recess

241: The first positioning part

242: second positioning part

25: gap

30: Chain guide

31: Cylinder

Figure 1 is a front view of the first preferred embodiment of the present invention mounted on the frame. Figure 2 is an exploded view of the main seat and the chain guide under the first preferred embodiment of the present invention. Figure 3 is a back view of the main seat under the first preferred embodiment of the present invention, showing that the column does not pass through the blocking end. Figure 4 is a back view of the main seat under the first preferred embodiment of the present invention, showing that the blocking member is pressed by the column. Figure 5 is a back view of the main seat under the first preferred embodiment of the present invention, showing that the column passes through the stop end. Figure 6 is a back view of the main seat under the second preferred embodiment of the present invention. Figure 7 is a back view of the main seat under the third preferred embodiment of the present invention. Figure 8 is a back view of the main seat under the fourth preferred embodiment of the present invention, showing that the adjuster is in the first position. Figure 9 is a back view of the main seat under the fourth preferred embodiment of the present invention, showing that the adjuster is in the second position.

20: Lower main seat

21: Groove

211: first end

212: second end

213: Fixed part

214: Dimple

22: blocking piece

221: Arm

222: Connection part

31: Cylinder

Claims (10)

A rear transmission with a buffer structure, installed on a frame, includes: A main seat is fixedly connected to the frame; The lower main seat is fixed to the upper main seat; A chain guide pivotally connected to the lower main seat; and A buffer structure includes a groove provided in the lower main seat, a blocking member provided in the groove, and a column with one end connected to the chain guide and the other end extending into the groove; wherein the The blocking member has an arm, and the arm has an elastic blocking end; when the chain guide pivots relative to the lower main base, the column will move in the groove; when the column abuts Even when crossing the blocking end of the blocking member, the blocking member will be deformed, so that the blocking member will provide a resistance when the cylinder moves. According to the rear transmission with a buffer structure according to claim 1, wherein the lower main seat is further provided with a fixing portion; the blocking member has a connecting portion, and the connecting portion is combined with the fixing portion. According to the rear transmission with a buffer structure according to claim 2, a recess is provided on one of the side walls of the groove, and the recess is spaced from the fixed portion by a predetermined distance; and the blocking member has a part abutting against the recess Bottom end. According to the rear transmission with a buffer structure according to claim 1, wherein the arm portion of the blocking member has a portion with a bending protrusion to form the blocking end. According to the rear transmission with a buffer structure according to claim 1, wherein the blocking member further has an arm portion, the arm portion has an elastic stop end; the stop ends of the two arm portions are opposite. According to the rear transmission with a buffer structure according to claim 1, wherein the lower main seat is further provided with a guide groove on the bottom surface of the groove, the width of which is slightly larger than the diameter of the cylinder, and the cylinder extends into the guide groove. According to claim 1, the rear transmission with a buffer structure further includes an adjuster, which is movably arranged on the lower main seat; the adjuster has an extension arm portion with a resisting portion; when the adjuster After moving, the abutting portion will abut on different positions on the arm portion of the blocking member. According to the rear transmission with a buffer structure according to claim 7, wherein the lower main seat has a concave portion communicating with the groove; the adjuster has a body, and the body is accommodated in the concave portion so that the adjuster can Move along the concave portion; one end of the extension arm portion is connected to the body, and the other end extends to the groove. According to claim 8, the rear transmission with a buffer structure, wherein the adjuster can move between a first position and a second position; one end of the recess is provided with a first positioning portion, and the other end is provided with a second positioning portion; The body is accommodated in the recess, one end has a first positioning part, and the other end has a second positioning part; when the adjuster moves to the first position, the first positioning part of the body and the recess When the adjuster moves to the second position, the second positioning portion of the body is combined with the second positioning portion of the concave portion. According to the rear transmission with a buffer structure according to claim 8, wherein the lower main seat further has a notch so that the recess can be connected to the outside of the lower main seat through the notch; the adjuster further has an operating portion connected to On one side of the body, the operating part extends out of the lower main seat from the gap.

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