High cable pull ratio rear derailleur

Abstract

The present invention discloses a high cable pull ratio rear derailleur, comprising: a base member fixedly mounted with an introduction nozzle; a guide pulley rotatably connected to the base member, the guide pulley being provided with a first guide wire curved surface, a transition guide wire curved surface, and a second guide wire curved surface in sequence along the axial direction, the first guide wire curved surface and the second guide wire curved surface both extending in the circumferential direction of the guide pulley, and the radius of the first guide wire curved surface being greater than the radius of the second guide wire curved surface; an outlet nozzle; a movable member rotatably connected to the derailleur on the left side; a parallel four-bar linkage mechanism formed by the base member, an inner swing block, a movable member, and an outer swing block; a wiring frame mounted on the outer swing block, the shift cable first passing through a winding portion and then being clamped on a clamping portion, the shift cable being able to pull the outer swing block to rotate relative to the base member in a first rotational direction; and an elastic reset member. During the process of pulling or releasing the shift cable, the shift cable is converted by the guide pulley ratio, thereby improving the cable pull ratio without increasing the volume of the rear derailleur.

Description

Technical Field

[0001] The present invention relates to the technical field of speed-changing bicycles, in particular to a rear derailleur. Background Art

[0002] The rear derailleur is an important component in a bicycle's speed shifting system. It usually includes a base member, a movable member, and a derailleur wheel. The movable member is connected to the base member through a parallel four-bar linkage. The derailleur wheel is mounted on the movable member. The derailleur wheel is responsible for shifting the chain between different flywheels on the rear wheel. One end of the shift cable (also known as the speed cable) is connected to the finger-shift transmission, and the other end is connected to the cable point extending from the parallel four-bar linkage. The finger-shift transmission pulls or releases the cable point through the shift cable, rotates the movable member, realizes the movement of the derailleur wheel, and achieves the purpose of shifting gears and speed.

[0003] The cable pull ratio is a key parameter in a bicycle's speed change system. It is specifically the ratio of the distance the shift cable moves in the finger-shift transmission to the actual distance the derailleur moves along the axial direction of the flywheel. It should be explained that the radial dimensions of different flywheels decrease from the inside to the outside. Since the movable component rotates to connect the base component through a parallel four-bar linkage, the derailleur moves along a curved trajectory. Moreover, when shifting gears, the chain switches between different flywheels, which will cause changes in tension and posture. In order to adapt to the changes in the chain, the derailleur and the tensioner will also move around the rotating shaft on the movable component relative to the flywheel. The sprockets rotate in a plane perpendicular to their axes, resulting in a complex derailleur motion. Therefore, the actual displacement of the derailleur is difficult to quantify and is of limited reference value. However, the axial spacing between adjacent sprockets is known. Therefore, the axial displacement of the derailleur as it drives the chain between sprockets is a quantifiable and meaningful value. Furthermore, during a shift, the distance the shift cable moves is determined by the axial spacing between the sprockets. Therefore, the distance the derailleur moves axially along the sprockets is more relevant. Furthermore, this means that the distance the shift cable moves during a shift is not linearly related to the actual distance the derailleur moves along the sprockets. This means that the actual cable pull ratio varies from gear to gear, albeit slightly. Therefore, the industry typically uses a single value to broadly describe the cable pull ratio parameter for a specific bicycle transmission system. Generally speaking, a higher cable pull ratio reduces the manual effort required for shifting and, after accounting for errors, results in higher shift accuracy.

[0004] In order to improve the cable pull ratio of a bicycle's transmission system, the actual distance the derailleur moves along the axial direction of the flywheel is taken as a constant. In order to ensure that the movable component still rotates the same angle each time it shifts gears, the pulling radius of the shift cable relative to the cable pull point is set to be larger to consume a longer shift cable movement distance. Ultimately, the volume of the rear derailleur will be designed too large, which will increase wind resistance, affect controllability, and may also reduce the overall coordination and aesthetics of the bicycle. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a high cable pull ratio rear derailleur that can effectively improve the cable pull ratio without increasing the size of the rear derailleur.

[0006] According to an embodiment of the present invention, a high-pull ratio rear derailleur has opposite first and second rotation directions, comprising: a base component configured to be mounted on a bicycle frame, wherein an introduction nozzle for inserting a shift cable is fixedly mounted on the base component; a wire pulley rotatably connected to the base component, wherein the wire pulley is sequentially provided with a first wire curved surface, a transition wire curved surface, and a second wire curved surface along the axial direction, wherein the first wire curved surface and the second wire curved surface both extend along the circumferential direction of the wire pulley and the radius of the first wire curved surface is greater than the radius of the second wire curved surface, the transition wire curved surface extends from the first wire curved surface toward the second wire curved surface, and after the shift cable is inserted through the introduction nozzle, it is sequentially wound on the first wire curved surface, the transition wire curved surface, and the second wire curved surface and can drive the wire pulley to rotate on the base component; and an outlet nozzle fixedly mounted on On the base component, the lead-out nozzle is used to pass out the shift wire wrapped on the second wire curved surface; the movable component is rotatably connected to the sprocket on the left side; the inner swing block, the front end of which is hinged to the movable component, and the rear end is hinged to the base component; the outer swing block, the front end of which is hinged to the movable component, and the rear end is hinged to the base component, and the base component, the inner swing block, the movable component and the outer swing block constitute a parallel four-bar linkage mechanism; the wiring frame is installed on the outer swing block, and the wiring frame is provided with a winding part and a clamping part. The shift wire after passing through the lead-out nozzle first bypasses the winding part and is then clamped on the clamping part, and the shift wire can pull the outer swing block to rotate relative to the base component along the first rotation direction; the elastic reset part is configured to apply a torque to the outer swing block to rotate relative to the base component along the second rotation direction.

[0007] At least the following beneficial effects are achieved: the derailleur wheel of the rear derailleur is connected to the bicycle frame by rotating through a parallel four-bar linkage mechanism, the guide nozzle can pass the shift cable, the shift cable is wound on the first wire curved surface, the transition wire curved surface and the second wire curved surface on the wire pulley in sequence, the guide nozzle passes the shift cable wound on the second wire curved surface out, then passes around the winding part of the wiring frame, and is then clamped on the wire clamping part; in the process of pulling or releasing the shift cable, the shift cable can drive the wire pulley to rotate synchronously on the base component, and drive the derailleur wheel to rotate through the parallel four-bar linkage mechanism; since the radius of the first wire curved surface is greater than the radius of the second wire curved surface, after the wire pulley rotates a certain angle, the shift cable moves a greater distance in the guide nozzle. The distance the shift cable moves in the guide nozzle is equal to the distance the shift cable moves in the shift transmission. The distance the shift cable moves in the guide nozzle determines the rotation angle of the outer swing block and is related to the actual distance the derailleur moves along the axial direction of the flywheel. After the shift cable is converted proportionally through the guide pulley, the cable pulling ratio is improved. On the other hand, there is no need to increase the cable pulling ratio by increasing the pulling radius of the shift cable to the terminal frame, and there is no need to increase the volume of the rear derailleur. The shift cable first passes around the winding part before being clamped in the wire clamping part, which ensures the smoothness of the shift cable during pulling or releasing, and prevents the shift cable from interfering with the parallel four-bar linkage.

[0008] According to some embodiments of the present invention, a radius of the first conductive line curved surface is 1.4 to 2.5 times a radius of the second conductive line curved surface.

[0009] According to some embodiments of the present invention, the wire wheel is provided with a flange protruding radially from one end of the second wire curved surface, the flange is provided with a groove extending circumferentially, the first wire curved surface constitutes the bottom of the groove, and the transition wire curved surface is gradually radially retracted from the first wire curved surface along the circumference of the flange and passes through the end face of the flange close to the second wire curved surface.

[0010] According to some embodiments of the present invention, a pivot shaft and a wire cover are fixedly mounted on the base component, the wire wheel is rotatably connected to the pivot shaft, the wire cover includes a disk body extending along an axial vertical plane of the pivot shaft, a first cover extending from the outer edge of the disk body along the axial direction of the pivot shaft to the opening of the groove, and a second cover extending from the disk body toward the end face of the flange, the disk body is close to the end of the second wire curved surface away from the flange, the disk body is used to constrain the shift wire to prevent the shift wire from deviating from the second wire curved surface in a direction away from the flange, the groove and the first cover cover define a first threading channel for the shift wire to pass through, the second wire curved surface, the end face of the flange, the second cover cover and the disk body jointly define a second threading channel for the shift wire to pass through.

[0011] According to some embodiments of the present invention, an extension line of the inlet nozzle is tangent to the first wire curved surface, the first threading channel extends from a position close to the inlet nozzle to the transition wire curved surface, the outlet nozzle is installed on the wire cover, an extension line of the outlet nozzle is tangent to the second wire curved surface, and the second threading channel extends from the transition wire curved surface to the outlet nozzle.

[0012] According to some embodiments of the present invention, the base component is sequentially installed with a first pivot and a second pivot along the left and right directions, the outlet nozzle is arranged between the first pivot and the second pivot in the left and right directions, the movable component is sequentially installed with a fourth pivot and a third pivot along the left and right directions, the axes of the first pivot, the second pivot, the third pivot and the fourth pivot are parallel to each other, the front end of the inner swing block is hinged to the movable component through the fourth pivot, and the rear end is hinged to the base component through the first pivot, the front end of the outer swing block is hinged to the movable component through the third pivot, and the rear end is hinged to the base component through the second pivot, the shift line can pull the outer swing block to rotate around the second pivot in a first rotation direction, the elastic return member is configured to apply a torque to the outer swing block to rotate around the second pivot in a second rotation direction, and the wiring frame is installed on the side of the outer swing block facing the inner swing block and is accommodated in the interior of the parallel four-bar linkage mechanism.

[0013] According to some embodiments of the present invention, the winding portion includes a winding groove arranged on the outer edge of the wiring frame, the extension trajectory of the winding groove is perpendicular to the axial direction of the second pivot and is an arc line with the second pivot as the center, and the opening of the winding groove is away from the second pivot.

[0014] According to some embodiments of the present invention, the winding portion includes a wire threading flare, the wire threading flare is connected to one end of the winding groove away from the wire clamping portion, and the inner swing block is provided with an avoidance groove on the side facing the winding portion. When the distance between the inner swing block and the outer swing block is the shortest, the winding portion extends into the avoidance groove, and the bottom of the avoidance groove and the winding groove are combined to form a third wire threading channel for the shift cable to pass through, and the third wire threading channel extends from the wire threading flare to the wire clamping portion.

[0015] According to some embodiments of the present invention, the wire clamping portion includes a positioning block, a pressure block and a fastener. The positioning block is fixedly mounted on the wiring frame. The pressure block can be fastened to the positioning block through the fastener. The pressure block is configured to cooperate with the positioning block to clamp the shift line. Before the pressure block and the positioning block clamp the shift line, a fourth wire threading channel is defined and formed between the positioning block, the pressure block and the fastener.

[0016] According to some embodiments of the present invention, a side stop is provided on the pressure block, extending toward the positioning block from one end away from the fastener. Before the pressure block and the positioning block clamp the shift cable, the fourth threading channel is defined and formed between the positioning block, the side stop, the pressure block and the fastener.

[0017] According to some embodiments of the present invention, the axial direction of the sprocket extends in the left-right direction, the axial direction of the second pivot is perpendicular to the axial direction of the sprocket, the axial direction of the fastener is not parallel to the axial direction of the second pivot, and the fourth threading channel extends downward or upward from one end close to the winding part.

[0018] According to some embodiments of the present invention, the positioning block is provided with an anti-slip groove on one side of the pressure block, and the anti-slip groove is configured to cooperate with the pressure block to clamp the shift cable, and the anti-slip groove can accommodate part of the shift cable to prevent the shift cable from deviating from the positioning block, and a plurality of protrusions are arranged at intervals along the extension direction in the anti-slip groove, and the protrusions extend from the bottom of the anti-slip groove toward the pressure block but do not exceed the opening of the anti-slip groove.

[0019] According to some embodiments of the present invention, the outer swing block is provided with a first stopper, and the base component is provided with a second stopper. When the parallel four-bar linkage is in one of the extreme positions, the second stopper stops the wiring frame, and when the parallel four-bar linkage is in the other extreme position, the first stopper stops the movable component.

[0020] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0022] Figure 1 Schematic diagram of the structure of an embodiment of the present invention;

[0023] Figure 2 This is a structural schematic diagram of a parallel four-bar linkage in an intermediate state according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of a portion of the structure after the wire cover is hidden in an embodiment of the present invention;

[0025] Figure 4 A schematic diagram of the coordination between the wire cover and the wire wheel in an embodiment of the present invention;

[0026] Figure 5 for Figure 4AA rotated cut view;

[0027] Figure 6 for Figure 4 An exploded diagram of one of the perspectives;

[0028] Figure 7 for Figure 4 A decomposition diagram from another perspective;

[0029] Figure 8 Schematic diagram of the structure of the parallel four-bar linkage according to an embodiment of the present invention when it is in one of its extreme positions;

[0030] Figure 9 for Figure 8 A schematic diagram of a portion of the structure from another perspective;

[0031] Figure 10 Schematic diagram of the structure of the parallel four-bar linkage according to the embodiment of the present invention when it is in another extreme position;

[0032] Figure 11 is a partial structural diagram of the parallel four-bar linkage in an embodiment of the present invention when it is in another extreme position;

[0033] Figure 12 Schematic diagram of the coordination between the inner and outer swing blocks and the wiring frame in an embodiment of the present invention;

[0034] Figure 13 Schematic diagram of the structure of the wiring rack in an embodiment of the present invention.

[0035] Reference numerals: shift cable 1, base member 2, pivot shaft 21, introduction nozzle 22, outlet nozzle 23, wire cover 24, disk 241, first cover 242, second cover 243, stopper 244, first pivot 25, second pivot 26, second stopper 27, movable member 3, third pivot 31, fourth pivot 32, derailleur 4, inner swing block 5, avoidance groove 51, outer swing block 6, first stopper 61, wiring rack 7, winding portion 71, winding groove 71 1. Wire threading flare 712, wire clamping portion 72, positioning block 721, pressure block 722, fastener 723, side stop 724, anti-slip groove 725, protrusion 726, wire pulley 8, first wire curved surface 81, transition wire curved surface 82, second wire curved surface 83, flange 84, groove 85, limit block 86, first wire threading channel 9, second wire threading channel 10, third wire threading channel 11, fourth wire threading channel 12, bearing 13, wire tube 14, elastic reset member 15. DETAILED DESCRIPTION

[0036] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, inside, outside, side, end, axial, radial, circumferential, rotational direction, circumferential direction, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] In the description of the present invention, if there is a description of first, second, third, and fourth, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0038] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0039] Reference Figures 1 to 13 The present invention discloses a high cable pull ratio rear derailleur, comprising a base component 2, a guide nozzle 23, a movable component 3, a derailleur wheel 4, an inner swing block 5, an outer swing block 6, a wiring frame 7, a wire pulley 8 and an elastic reset member 15.

[0040] Among them, reference Figure 1 and Figure 3 The base member 2 is configured to be mounted on a bicycle frame. The base member 2 is a fixed part of the rear derailleur. An introduction nozzle 22 is fixedly mounted on the base member 2. The introduction nozzle 22 can be regarded as the input end of the guide wheel 8 and is used to insert the shift cable 1. In addition, the introduction nozzle 22 can also lock the wire tube 14 outside the shift cable 1, so that the shift cable 1 can slide and shuttle in the wire tube 14.

[0041] Reference Figure 3 、 Figure 4 and Figure 5The wire wheel 8 is rotatably connected to the base component 2, and the wire wheel 8 is sequentially provided with a first wire curved surface 81, a transition wire curved surface 82 and a second wire curved surface 83 along the axial direction. The first wire curved surface 81 and the second wire curved surface 83 both extend along the circumferential direction of the wire wheel 8. It should be noted that the first wire curved surface 81 is a section of a cylindrical surface, and the radius of each point on the first wire curved surface 81 is consistent; the second wire curved surface 83 is a section of a cylindrical surface or a completely closed cylindrical surface, and the radius of each point on the second wire curved surface 83 is consistent, wherein the radius of the first wire curved surface 81 is greater than the radius of the second wire curved surface 83, and the transition wire curved surface 82 extends from the first wire curved surface 81 toward the second wire curved surface 83. After the shift wire 1 is inserted into the introduction nozzle 22, it is sequentially wound around the first wire curved surface 81, the transition wire curved surface 82 and the second wire curved surface 83 and can drive the wire wheel 8 to rotate on the base component 2.

[0042] Reference Figure 2 The outlet nozzle 23 is fixedly mounted on the base member 2. The outlet nozzle 23 is used to pass the shift wire 1 wound on the second wire curved surface 83 out. The outlet nozzle 23 can be regarded as the output end of the wire wheel 8.

[0043] Reference Figure 2 、 Figure 8 、 Figure 9 and Figure 10 The left side of the movable member 3 is connected to the derailleur wheel 4 by rotation. The derailleur wheel 4 can rotate around its own axis relative to the movable member 3. When shifting, the chain switches between different flywheels, which will cause changes in tension and posture. In order to adapt to the changes in the chain, the derailleur wheel 4 and the tensioner will also rotate around the rotating shaft on the movable member 3 in a plane perpendicular to the axis of the flywheel. For details, please refer to Figure 2 、 Figure 8 and Figure 10 , the actual motion trajectory of the sprocket wheel 4 is very complicated.

[0044] Among them, the front end of the inner swing block 5 is hinged to the movable member 3, and the rear end is hinged to the base member 2. The front end of the outer swing block 6 is hinged to the movable member 3, and the rear end is hinged to the base member 2. The base member 2, the inner swing block 5, the movable member 3 and the outer swing block 6 are hinged in sequence to form a parallel four-bar linkage mechanism. Figure 2 、 Figure 8 and Figure 10 The structural schematic diagrams of the parallel four-bar linkage are shown in the middle state and two extreme positions respectively.

[0045] Reference Figure 2 The wiring frame 7 is installed on the outer swing block 6. The wiring frame 7 is provided with a winding portion 71 and a wire clamping portion 72. The shift wire 1 after passing through the outlet nozzle 23 first passes around the winding portion 71 and is then clamped on the wire clamping portion 72. The shift wire 1 can pull the outer swing block 6 to rotate relative to the base component 2 along the first rotation direction.

[0046] Reference Figure 2 、 Figure 8 and Figure 10 The elastic return member 15 is configured to apply a torque to the outer swing block 6 relative to the base member 2 in a second rotational direction, wherein the second rotational direction is opposite to the first rotational direction. When the shifter releases the shift cable 1, the elastic return member 15 can force the outer swing block 6 to rotate in the second rotational direction to achieve the purpose of reset and keep the shift cable 1 always in a tensioned state.

[0047] The derailleur wheel 4 is rotatably connected to the frame through a parallel four-bar linkage. As for the shift cable 1, the end of the shift cable 1 away from the rear derailleur can be connected to the finger-shift transmission, and the introduction nozzle 22 can allow the end of the shift cable 1 close to the rear derailleur to pass through. The shift cable 1 is wound on the first wire curved surface 81, the transition wire curved surface 82 and the second wire curved surface 83 on the wire pulley 8 in sequence. The lead-out nozzle 23 passes the shift cable 1 wound on the second wire curved surface 83 out, then passes around the winding part 71 of the wiring frame 7, and is then clamped on the wire clamping part 72.

[0048] In the process of pulling the shift cable 1, the shift cable 1 can drive the wire pulley 8 to rotate synchronously on the base component 2. The wire pulley 8 specifically rotates along the Figure 3 The counterclockwise rotation shown causes the winding portion of the shift cable 1 on the first wire curved surface 81 to decrease and the winding portion on the second wire curved surface 83 to increase;

[0049] In the process of releasing the shift cable 1, an elastic reset mechanism is provided in the rear derailleur. The elastic reset member 15 forces the outer swing block 6 to rotate along the second rotation direction, so that the shift cable 1 drives the guide wheel 8 to rotate synchronously on the base member 2. The guide wheel 8 specifically rotates along the second rotation direction. Figure 3 The clockwise rotation as shown causes the winding portion of the shift cable 1 on the first wire curved surface 81 to increase and the winding portion on the second wire curved surface 83 to decrease.

[0050] Since the radius of the first wire curved surface 81 is greater than the radius of the second wire curved surface 83, after the wire pulley 8 rotates a certain angle, the distance the shift cable 1 moves in the inlet nozzle 22 is greater than the distance it moves in the outlet nozzle 23, wherein the distance the shift cable 1 moves in the inlet nozzle 22 is equal to the distance the shift cable 1 is moved by the finger shift transmission, and the distance the shift cable 1 moves in the outlet nozzle 23 determines the rotation angle of the outer swing block 6 and is related to the actual distance the derailleur 4 moves along the axial direction of the flywheel. After the shift cable 1 is proportionally converted by the wire pulley 8, the cable pulling ratio is improved. On the other hand, there is no need to increase the cable pulling ratio by increasing the pulling radius of the shift cable 1 to the wire frame 7, and there is no need to increase the volume of the rear derailleur. Moreover, the shift cable 1 first passes around the winding portion 71 before being clamped in the wire clamping portion 72, which ensures the smoothness of the shift cable 1 during pulling or releasing, and prevents the shift cable 1 from interfering with the parallel four-bar linkage.

[0051] In some embodiments of the present invention, reference Figure 5 and Figure 7 The radius of the first wire curved surface 81 is 1.4 to 2.5 times the radius of the second wire curved surface 83 . After the shift wire 1 is converted by the proportional conversion of the wire pulley 8 , the wire pulling ratio is increased to 1.4 to 2.5 accordingly.

[0052] In some embodiments, reference Figure 3 and Figure 7 The wire pulley 8 is provided with a flange 84 protruding radially from one end of the second wire curved surface 83, and the flange 84 is provided with a groove 85 extending circumferentially. The first wire curved surface 81 constitutes the bottom of the groove 85. The groove 85 can constrain the shift wire 1 and prevent the shift wire 1 from deviating from the first wire curved surface 81.

[0053] Among them, reference Figure 3 and Figure 7 The transition wire curved surface 82 gradually radially shrinks from the first wire curved surface 81 along the circumference of the flange 84 and passes through the end surface of the second wire curved surface 83 close to the flange 84, so that the shift cable 1 can smoothly transition from the first wire curved surface 81 to the second wire curved surface 83 without getting stuck.

[0054] In some embodiments, reference Figure 1 、 Figure 4 and Figure 5 A pivot shaft 21 and a wire cover 24 are fixedly mounted on the base member 2. The wire wheel 8 is rotatably connected to the pivot shaft 21 to enable the wire wheel 8 to rotate relative to the base member 2. The wire cover 24 includes a disk body 241 extending along the axial vertical plane of the pivot shaft 21. The disk body 241 is close to the end of the second wire curved surface 83 away from the flange 84. The disk body 241 is used to constrain the shift cable 1 to prevent the shift cable 1 from deviating from the second wire curved surface 83 in a direction away from the flange 84.

[0055] Reference Figure 5 and Figure 6 The wire cover 24 also includes a first cover 242 extending from the outer edge of the disk body 241 along the axial direction of the pivot shaft 21 to the opening of the groove 85. The second cover 243 does not contact the end surface of the flange 84. The groove 85 and the first cover 242 define a first threading channel 9 for the shift cable 1 to pass through.

[0056] Reference Figure 5 The wire cover 24 also includes a second cover 243 extending from the disk body 241 toward the end face of the flange 84. The second cover 243 does not contact the end face of the flange 84. The second wire curved surface 83, the end face of the flange 84, the second cover 243 and the disk body 241 jointly define a second wire threading channel 10 for the shift cable 1 to pass through.

[0057] Reference Figure 1 、 Figure 3 、 Figure 5 、 Figure 6 and Figure 7 In some embodiments, the extension line of the inlet nozzle 22 is tangent to the first wire curved surface 81, the first threading channel 9 extends from a position close to the inlet nozzle 22 to the transition wire curved surface 82, the outlet nozzle 23 is installed on the wire cover 24, the extension line of the outlet nozzle 23 is tangent to the second wire curved surface 83, and the second threading channel 10 extends from the transition wire curved surface 82 to the outlet nozzle 23.

[0058] The first threading channel 9 and the second threading channel 10 can not only constrain the shift cable 1 in the working state, but also play a guiding role when the shift cable 1 is installed into the wire pulley 8, so that the shift cable 1 inserted from the inlet nozzle 22 can pass through the first threading channel 9 and the second threading channel 10 in sequence in a relaxed state and pass out from the outlet nozzle 23.

[0059] In addition, refer to Figure 1 , a limit block 86 may be provided on the wire wheel 8, and a stop block 244 may be provided on the wire cover 24. The stop block 244 is configured to stop the limit block 86 to limit the rotation range of the wire wheel 8 relative to the wire cover 24. Figure 5 The wire pulley 8 can be rotatably connected to the pivot shaft 21 through the bearing 13. The inner ring of the bearing 13 is installed on the pivot shaft 21, and the wire pulley 8 is installed on the outer ring of the bearing 13. The pivot shaft 21 locks the bearing 13 on the limiting flange of the pivot shaft 21 through a nut, so that the axial position of the bearing 13 relative to the pivot shaft 21 is fixed. The bearing 13 can reduce the wear on the wire pulley 8 and the pivot shaft 21, and protect the wire pulley 8 and the pivot shaft 21.

[0060] In some embodiments, reference Figure 2 、 Figure 8 、 Figure 9 and Figure 10 The base component 2 is sequentially installed with a first pivot 25 and a second pivot 26 along the left and right directions, and the movable component 3 is sequentially installed with a fourth pivot 32 and a third pivot 31 along the left and right directions. The axes of the first pivot 25, the second pivot 26, the third pivot 31 and the fourth pivot 32 are parallel to each other. The front end of the inner swing block 5 is hinged to the movable component 3 through the fourth pivot 32, and the rear end is hinged to the base component 2 through the first pivot 25. The front end of the outer swing block 6 is hinged to the movable component 3 through the third pivot 31, and the rear end is hinged to the base component 2 through the second pivot 26. The parallel four-bar linkage is a three-dimensional spatial structure. The shift cable 1 can pull the outer swing block 6 to rotate around the second pivot 26 in the first rotation direction. The elastic reset member 15 is configured to apply a torque to the outer swing block 6 to rotate around the second pivot 26 in the second rotation direction.

[0061] In a traditional rear derailleur, the cable pulling point generally uses a clamping screw to fix the shift cable 1, which is set below the parallel four-bar linkage or on the outside of the parallel four-bar linkage away from the frame. The shift cable 1 and the cable pulling point are easily damaged by accidental collisions, scratches, etc., and are also easily contaminated by external impurities such as mud and dust. As a result, the shift cable 1 is not smooth during the pulling process and needs to be cleaned regularly. In addition, the external connection point will destroy the overall streamlined design of the bicycle and reduce its aesthetics.

[0062] Based on this, in some embodiments of the present invention, the outlet nozzle 23 is arranged between the first pivot 25 and the second pivot 26 in the left and right directions, and the wiring frame 7 is installed on the side of the outer swing block 6 facing the inner swing block 5, and is accommodated inside the parallel four-bar linkage mechanism, ensuring that the line segment of the shift cable 1 from the outlet nozzle 23 to the wire clamping part 72 is all inside the parallel four-bar linkage mechanism, effectively enclosing and protecting the shift cable 1, the winding part 71 and the wire clamping part 72, avoiding accidental damage such as collision and scratching, and reducing the adhesion and contamination of external impurities such as mud and dust, further ensuring the smoothness of the shift cable 1 during pulling or releasing, without the need for frequent cleaning, and also improving the overall streamlined design and aesthetics of the bicycle.

[0063] It should be emphasized that the wiring frame 7 is accommodated inside the parallel four-bar linkage, which can fully utilize the internal space of the parallel four-bar linkage, effectively reduce the volume occupied by the rear derailleur, and realize a compact design of the derailleur.

[0064] In some embodiments, reference Figure 12 and Figure 13The winding portion 71 includes a winding groove 711 arranged on the outer edge of the wiring frame 7. The extension trajectory of the winding groove 711 is perpendicular to the axial direction of the second pivot 26 and is an arc line with the second pivot 26 as the center. The opening of the winding groove 711 is away from the second pivot 26. It can be understood that the extension trajectory of the winding groove 711 is in the same plane, and the axial direction of the second pivot 26 is perpendicular to the plane where the extension trajectory of the winding groove 711 is located.

[0065] When the shift cable 1 is pulled or released, the winding groove 711 just rotates around the second pivot 26. That is to say, when the shift cable 1 is pulled or released, the line segment of the shift cable 1 between the outlet nozzle 23 and the winding groove 711 always maintains the same length and posture. Assuming that the winding groove 711 rotates a certain angle, the shift cable 1 just pulls or releases the arc length corresponding to the angle on the winding groove 711, and the angle of rotation of the winding groove 711 can correspond to the distance that the sprocket 4 moves along its axial direction. Therefore, the length of the shift cable 1 required to pull or release each gear shift of the finger-shift transmission can be easily designed according to the axial distance between different flywheels.

[0066] In some embodiments, reference Figure 11 and Figure 13 In some embodiments, the winding portion 71 includes a wire threading flare 712, which is connected to the end of the winding groove 711 away from the wire clamping portion 72. The wire threading flare 712 gradually expands in the direction approaching the outlet nozzle 23 and gradually shrinks in the direction approaching the winding groove 711. The inner swing block 5 is provided with an avoidance groove 51 on the side facing the winding portion 71. When the distance between the inner swing block 5 and the outer swing block 6 is the shortest, the winding portion 71 extends into the avoidance groove 51. The bottom of the avoidance groove 51 and the winding groove 711 are enclosed to form a third wire threading channel 11 for the shift cable 1 to pass through. The third wire threading channel 11 extends from the wire threading flare 712 to the wire clamping portion 72.

[0067] It is understandable that when the clamping portion 72 is not yet connected to the shift cable 1, the shift cable 1 cannot exert a pulling effect on the parallel four-bar linkage. At this time, the parallel four-bar linkage is in another extreme position under the action of the elastic reset member 15. Figure 10 and Figure 11 , the distance between the inner swing block 5 and the outer swing block 6 is set to the shortest at this time, and the bottom of the avoidance groove 51 and the winding groove 711 are enclosed to form a third threading channel 11 for the shift cable 1 to pass through. The third threading channel 11 extends from the threading flare 712 to the wire clamping portion 72, so that the shift cable 1 passing through the outlet nozzle 23 is conveniently inserted into the threading flare 712 smoothly, and further enters the third threading channel 11 through the guiding effect of the threading flare 712, and gradually extends along the internal space of the third threading channel 11 to the wire clamping portion 72, so that the shift cable 1 can smoothly bypass the winding groove 711 and be installed on the wire clamping portion 72.

[0068] Moreover, the design of the avoidance groove 51 can also maximize the use of the internal space of the parallel four-bar linkage, so that the pulling radius of the shift cable 1 relative to the second pivot 26 can be designed to be maximized, that is, the rotation radius of the winding groove 711 around the second pivot 26 can be designed to be maximized, which means that in order to make the winding groove 711 rotate the same angle, the shift cable 1 needs to be pulled or released a longer distance, thereby improving the cable pulling ratio of the bicycle.

[0069] In some embodiments, reference Figure 12 and Figure 13 When the lock is unlocked, the latch 72 is unlocked and the latch 72 is in place, so that the lock 72 is locked. When the lock is unlocked, the latch 72 is unlocked and the lock is in place, so that the lock 72 is unlocked.

[0070] In some embodiments, a side stopper 724 is provided on the pressure block 722 at one end away from the fastener 723 and extending toward the positioning block 721. Before the pressure block 722 and the positioning block 721 clamp the shift cable 1, the fourth threading channel 12 is specifically defined and formed between the positioning block 721, the side stopper 724, the pressure block 722 and the fastener 723. When the shift cable 1 passes through the fourth threading channel 12, the side stopper 724 can prevent the shift cable 1 from escaping from the fourth threading channel 12.

[0071] In some embodiments, the axial direction of the sprocket 4 extends in the left-right direction so that the extension plane of the sprocket 4 remains parallel to the flywheel plate, and the axial directions of the second pivot 26 and the third pivot 31 are perpendicular to the axial direction of the sprocket 4, so that the outer swing block 6 is roughly vertical, the axial direction of the fastener 723 is not parallel to the axial direction of the second pivot 26, and the fourth threading channel 12 extends downward or upward from one end close to the winding portion 71.

[0072] When the shift cable 1 passes through the fourth threading channel 12, it also tilts downward or upward, and can directly pass through the parallel four-bar linkage mechanism downward or upward, or bend downward or upward after hitting the outer swing block 6 and pass through the parallel four-bar linkage mechanism. The shift cable 1 passing through the parallel four-bar linkage mechanism provides the user with operating space, so that the user can clamp the end of the shift cable 1 and tighten the shift cable 1, and then tighten the fastener 723 to clamp the pressure block 722 and the positioning block 721 to fix the shift cable 1, so as to facilitate the installation of the shift cable 1.

[0073] In some embodiments, reference Figure 13 When the lever 721 is in the unlocked position, the locking cam 722 is locked and the locking cam 724 is locked, so that the pinion 720 can be locked in the unlocked position when the pinion 721 is unlocked.

[0074] Reference Figure 8 、 Figure 9 、 Figure 10 and Figure 12 The outer swing block 6 is provided with a first stop 61, and the base member 2 is provided with a second stop 27. When the parallel four-bar linkage is in one of the extreme positions, the second stop 27 stops the wiring frame 7. At this time, the sprocket 4 is in the leftmost position, and the chain is installed on the leftmost flywheel; when the parallel four-bar linkage is in the other extreme position, the first stop 61 stops the movable member 3. At this time, the sprocket 4 is in the rightmost position, and the chain is installed on the rightmost flywheel.

[0075] Reference Figure 9 The elastic reset member 15 can be specifically a tension spring. The elastic reset member 15 is arranged between the fourth pivot 32 and the position of the outer swing block 6 that deviates from the third pivot 31. It should be noted that in the entire process of the parallel four-bar linkage moving from another extreme position to one of the extreme positions, that is, Figure 10 The state shown moves to Figure 8During the entire process of the shown state, the elastic return member 15 is gradually stretched. Then, when the shift cable 1 is released by the finger-shift transmission, the elastic return member 15 has a tendency to pull back and recover, which can force the fourth pivot 32 to approach the outer swing block 6, that is, the outer swing block 6 and the inner swing block 5 both rotate along the second rotation direction, so as to achieve the purpose of reset and keep the shift cable 1 always in a tensioned state.

[0076] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] Of course, the present invention is not limited to the above-mentioned embodiments. Those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A high cable pull ratio rear derailleur, characterized in that: Having a first rotation direction and a second rotation direction that are opposite, comprising: A base member configured to be mounted on a vehicle frame, wherein an introduction nozzle for inserting a shift cable is fixedly mounted on the base member; A wire wheel is rotatably connected to the base component, and the wire wheel is sequentially provided with a first wire curved surface, a transition wire curved surface, and a second wire curved surface along the axial direction. The first wire curved surface and the second wire curved surface both extend along the circumferential direction of the wire wheel, and the radius of the first wire curved surface is greater than the radius of the second wire curved surface. The transition wire curved surface extends from the first wire curved surface toward the second wire curved surface. After the shift wire is passed through the introduction nozzle, it is sequentially wound on the first wire curved surface, the transition wire curved surface, and the second wire curved surface and can drive the wire wheel to rotate on the base component. a lead-out nozzle, fixedly mounted on the base component, and used for passing the shift wire wound on the second wire curved surface out; The movable member is rotatably connected to the derailleur wheel on the left side; An inner swing block, the front end of which is hinged to the movable member, and the rear end of which is hinged to the base member; An outer swing block, the front end of which is hinged to the movable member, and the rear end of which is hinged to the base member, wherein the base member, the inner swing block, the movable member and the outer swing block form a parallel four-bar linkage mechanism; a wiring frame mounted on the outer swing block, the wiring frame being provided with a winding portion and a wire clamping portion. The shift wire passing through the outlet nozzle first passes around the winding portion and is then clamped on the wire clamping portion. The shift wire can pull the outer swing block to rotate relative to the base member in a first rotational direction. The elastic return member is configured to apply a torque to the outer swing block to rotate relative to the base component along the second rotation direction.

2. The high cable pull ratio rear derailleur according to claim 1, characterized in that: The radius of the first conductive line curved surface is 1.4 to 2.5 times the radius of the second conductive line curved surface.

3. The high cable pull ratio rear derailleur according to claim 1 or 2, characterized in that: The wire wheel is provided with a flange protruding radially from one end of the second wire curved surface, and the flange is provided with a groove extending circumferentially. The first wire curved surface constitutes the bottom of the groove, and the transition wire curved surface gradually radially shrinks from the first wire curved surface along the circumference of the flange and passes through the end face of the flange close to the second wire curved surface.

4. The high cable pull ratio rear derailleur according to claim 3, characterized in that: The cam is secured to the base with a secure connection to the cam, and the cam is secured to the base with a secure connection to the cam.

5. The high cable pull ratio rear derailleur according to claim 4, characterized in that: The extension line of the introduction nozzle is tangent to the first wire curved surface, the first threading channel extends from a position close to the introduction nozzle to the transition wire curved surface, the outlet nozzle is installed on the wire cover, the extension line of the outlet nozzle is tangent to the second wire curved surface, and the second threading channel extends from the transition wire curved surface to the outlet nozzle.

6. The high cable pull ratio rear derailleur according to claim 1, wherein: The first pivot and the second pivot are installed in sequence along the left and right directions of the base component, and the outlet nozzle is arranged between the first pivot and the second pivot in the left and right directions, and the movable component is installed in sequence along the left and right directions, and the axes of the first pivot, the second pivot, the third pivot and the fourth pivot are parallel to each other, and the front end of the inner swing block is hinged to the movable component through the fourth pivot, and the rear end is hinged to the base component through the first pivot, and the front end of the outer swing block is hinged to the movable component through the third pivot, and the rear end is hinged to the base component through the second pivot. The shift line can pull the outer swing block to rotate around the second pivot in the first rotation direction, and the elastic return member is configured to apply a torque to the outer swing block to rotate around the second pivot in the second rotation direction, and the wiring frame is installed on the outer swing block towards the side of the inner swing block and is accommodated in the interior of the parallel four-bar linkage mechanism.

7. The high cable pull ratio rear derailleur according to claim 6, characterized in that: The winding portion includes a winding groove arranged on the outer edge of the wiring frame. The extension track of the winding groove is perpendicular to the axial direction of the second pivot and is an arc line with the second pivot as the center. The opening of the winding groove is away from the second pivot.

8. The high cable pull ratio rear derailleur according to claim 7, wherein: The winding portion includes a wire threading flare, which is connected to an end of the winding groove away from the wire clamping portion. The inner swing block is provided with an avoidance groove on the side facing the winding portion. When the distance between the inner swing block and the outer swing block is the shortest, the winding portion extends into the avoidance groove. The bottom of the avoidance groove and the winding groove are combined to form a third wire threading channel for the shift cable to pass through. The third wire threading channel extends from the wire threading flare to the wire clamping portion.

9. The high cable pull ratio rear derailleur according to claim 6, wherein: The wire clamping portion includes a positioning block, a pressure block and a fastener. The positioning block is fixedly mounted on the wiring frame. The pressure block can be fastened to the positioning block through the fastener. The pressure block is configured to cooperate with the positioning block to clamp the shift wire. Before the pressure block and the positioning block clamp the shift wire, a fourth wire threading channel is defined between the positioning block, the pressure block and the fastener.

10. The high cable pull ratio rear derailleur according to claim 9, wherein: A side stopper is provided on the pressure block at one end away from the fastener and extends toward the positioning block. Before the pressure block and the positioning block clamp the shift cable, the fourth threading channel is defined and formed between the positioning block, the side stopper, the pressure block and the fastener.

11. The high cable pull ratio rear derailleur according to claim 9 or 10, characterized in that: The axial direction of the sprocket extends in the left-right direction, the axial direction of the second pivot is perpendicular to the axial direction of the sprocket, the axial direction of the fastener is not parallel to the axial direction of the second pivot, and the fourth threading channel extends downward or upward from one end close to the winding part.

12. The high cable pull ratio rear derailleur according to claim 9, wherein: The positioning block is provided with an anti-slip groove on one side facing the pressure block, and the anti-slip groove is configured to cooperate with the pressure block to clamp the shift cable. The anti-slip groove can accommodate part of the shift cable to prevent the shift cable from deviating from the positioning block. A plurality of protrusions are arranged at intervals along the extension direction in the anti-slip groove, and the protrusions extend from the bottom of the anti-slip groove toward the pressure block but do not exceed the opening of the anti-slip groove.

13. The high cable pull ratio rear derailleur according to claim 1, wherein: The outer swing block is provided with a first stopper, and the base component is provided with a second stopper. When the parallel four-bar linkage is in one of the extreme positions, the second stopper stops the wiring frame, and when the parallel four-bar linkage is in the other extreme position, the first stopper stops the movable component.

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