Gear shifting mechanism and transmission

Abstract

The invention discloses a gear shifting mechanism and discloses a transmission with the gear shifting mechanism, the gear shifting mechanism comprises a gear shifting rod, an input gear and an elastic buffer piece, and the input gear is used for being meshed with an output gear of a gear shifting driving mechanism; the input gear drives the gear shifting rod to rotate through the elastic buffering piece so as to achieve gear shifting of the transmission. Due to the fact that the elastic buffering piece has the elastic deformation capacity, the elastic buffering piece has the force storage and buffering functions, when the elastic buffering piece has certain elastic deformation, the elastic buffering piece can drive the gear shifting rod to rotate, and the gear shifting smoothness of the gear shifting mechanism and the transmission can be improved. Due to the buffering effect of the elastic buffering piece, the input gear can rotate by a certain angle relative to the gear shifting rod when the gear shifting rod is in a stuck state, so that a motor and a transmission mechanism of the gear shifting driving mechanism are prevented from being overloaded or stuck, and then the risk that the gear shifting driving mechanism and a transmission are damaged is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bicycles, in particular to a shifting mechanism and a derailleur having the same. BACKGROUND

[0002] The derailleur is an indispensable device for a bicycle to achieve gear shifting. The internal derailleur includes a main shaft, a clutch mechanism, a planetary carrier mechanism, a hub, a shifting mechanism and a shifting drive mechanism, etc. The output gear of the shifting drive mechanism drives the shifting mechanism to rotate, and under the cooperation of the gears of each clutch mechanism and planetary carrier mechanism, gear shifting is achieved. Due to the existence of shifting resistance, especially in the state of riding, the shifting resistance received by the shifting mechanism in a certain moment can reach a large value, which can easily cause the shifting mechanism to be stuck and the shifting drive mechanism to be damaged. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a shifting mechanism which can improve the smoothness of the derailleur shifting and reduce the risk of damage to the shifting drive mechanism and the derailleur.

[0004] The present application also proposes a derailleur having the above-mentioned shifting mechanism.

[0005] According to the shifting mechanism of the first aspect of the present application, the shifting mechanism comprises a shifting lever, an input gear and an elastic buffer. The shifting lever is provided with a first driving part. The input gear is used to mesh with the output gear of the shifting drive mechanism. The input gear is provided with a second driving part. The elastic buffer has two connecting parts. One of the connecting parts is connected to or abuts against the first driving part. The other connecting part is connected to or abuts against the second driving part. The input gear drives the shifting lever to rotate through the elastic buffer to achieve the gear shifting of the derailleur.

[0006] At least has the following beneficial effects: Due to the elastic deformation capability of the elastic buffer, the elastic buffer has the functions of force storage and buffering. When the elastic buffer is elastically deformed, the elastic buffer can drive the shifting lever to rotate, which helps to improve the smoothness of the shifting mechanism and the derailleur shifting. Due to the buffering effect of the elastic buffer, when the shifting lever is stuck, the input gear can rotate by a certain angle relative to the shifting lever, thereby avoiding the overloading or sticking of the motor and transmission mechanism of the shifting drive mechanism, and reducing the risk of damage to the shifting drive mechanism and the derailleur.

[0007] According to some embodiments of the present application, the elastic buffer is a torsion spring, and the elastic buffer is sleeved on one end of the shifting lever.

[0008] According to some embodiments of the present application, the end of the gear shift lever is provided with a first clamping groove, and the input gear is provided with a second clamping groove, the first clamping groove and the second clamping groove are respectively the first driving part and the second driving part, and the two connecting parts are respectively clamped into the first clamping groove and the second clamping groove.

[0009] According to some embodiments of the present application, the end of the gear shift lever is provided with a limiting groove, the input gear is provided with a mounting hole, the inner wall of the mounting hole is provided with a limiting block, and the limiting block is arranged in the limiting groove, so that the input gear is kept synchronous rotation after rotating an angle relative to the gear shift lever.

[0010] According to some embodiments of the present application, the first clamping groove and the limiting groove are distributed along the axial direction of the gear shift lever, and the first clamping groove and the limiting groove are connected.

[0011] According to some embodiments of the present application, the side surface of the input gear is provided with an annular receiving groove, and the main body of the elastic buffer is arranged in the receiving groove.

[0012] According to some embodiments of the present application, the second clamping groove penetrates the side wall of the receiving groove and the outer tooth surface of the input gear, or the second clamping groove is arranged on the side surface of the input gear, and the depth direction of the second clamping groove is parallel to the axial direction of the input gear.

[0013] According to some embodiments of the present application, the number of the elastic buffers is multiple, the multiple elastic buffers are annularly distributed on the circumferential side of the gear shift lever, the gear shift lever is provided with multiple first driving parts, the input gear is provided with multiple second driving parts, and the multiple elastic buffers, the multiple first driving parts and the multiple second driving parts are one-to-one corresponding.

[0014] According to some embodiments of the present application, the outer circular surface of the gear shift lever is provided with a first sliding groove, a first pin shaft is arranged in the first sliding groove, when the gear shift lever rotates, the two opposite inner walls of the first sliding groove drive the first pin shaft to move along the axial direction of the gear shift lever, and the first pin shaft is used to drive the clutch wheel of the clutch mechanism to move along the axial direction of the gear shift lever, so as to open or close the clutch mechanism.

[0015] The transmission according to the second aspect of the embodiments of the present application comprises the gear shift mechanism according to the first aspect of the embodiments of the present application and the transmission body.

[0016] At least has the following beneficial effects: Due to the buffering effect of the elastic buffer, the motor and the transmission mechanism of the gear shift driving mechanism are prevented from being overloaded or stuck, thereby reducing the risk of damage of the gear shift driving mechanism and the transmission.

[0017] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and the attendant drawings or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0018] The application will be further described by examples in conjunction with the accompanying drawings, in which: Figure 1 It is one of the structural schematic diagrams of the embodiment of the application; Figure 2 It is one of the partial exploded views of the embodiment of the application; Figure 3 It is the second partial exploded view of the embodiment of the application; Figure 4 It is the side structural schematic diagram of the embodiment of the application; Figure 5 It is the sectional structural schematic diagram of the input gear, the elastic buffer, the shift lever, the first protrusion and the second protrusion of the embodiment of the application; Figure 6 It is the structural schematic diagram of the input gear of the embodiment of the application; Figure 7 It is the structural schematic diagram of the clutch wheel, the sun gear and the main shaft of the embodiment of the application; Figure 8 It is the sectional structural schematic diagram of the sun gear and the clutch wheel when they are engaged with each other of the embodiment of the application; Figure 9 It is the sectional structural schematic diagram of the clutch wheel of the embodiment of the application; Figure 10 It is the sectional structural schematic diagram of the sun gear and the clutch wheel when they are engaged with each other of another embodiment of the application; Figure 11 It is the sectional structural schematic diagram of the clutch wheel of another embodiment of the application; Figure 12 It is the structural schematic diagram of another embodiment of the shift lever of the application; REFERENCE NUMERALS The shift lever 100, the first clamping slot 110, the limiting slot 120, the first sliding slot 130, the second sliding slot 140, the first protrusion 150; The input gear 200, the second clamping slot 210, the mounting hole 220, the limiting block 230, the receiving slot 240, the second protrusion 250; The elastic buffer 300; The clutch wheel 400, the second ratchet tooth 410, the second engagement surface 411, the second separation part 4111, the second inclined surface part 4112; The sun gear 500, the first ratchet tooth 510, the first engagement surface 511, the first separation part 5111, the first inclined surface part 5112; Main shaft 600. DETAILED DESCRIPTION

[0019] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by the upper, lower, front, rear, left, right and the like, is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and cannot be understood as indicating or implying that the device or element indicated must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0020] In the description of the present application, if the first, second, etc. are described, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying the relative importance of the technical features or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0021] In the description of the present application, unless otherwise explicitly limited, the words such as arrangement, installation, connection and the like should be broadly understood, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0022] Reference Figures 1 to 3 The present application discloses a gear shifting mechanism, comprising a gear shifting lever 100, an input gear 200 and an elastic buffer 300, the gear shifting lever 100 is provided with a first driving part; the input gear 200 is used for meshing with the output gear of a gear shifting driving mechanism, and the input gear 200 is provided with a second driving part; the elastic buffer 300 has two connecting parts, one connecting part is connected or abuts against the first driving part, and the other connecting part is connected or abuts against the second driving part, and the input gear 200 drives the gear shifting lever 100 to rotate through the elastic buffer 300, so as to realize the gear shifting of the transmission.

[0023] The output gear of the gear shifting driving mechanism drives the input gear 200 to rotate, the input gear 200 drives the gear shifting lever 100 to rotate in turn through the second driving part, the elastic buffer 300 and the first driving part, and the input gear 200 drives the gear shifting lever 100 to rotate through the elastic buffer 300, so as to realize the gear shifting of the transmission. Since the elastic buffer 300 has the ability of elastic deformation, the elastic buffer 300 has the functions of force storage and buffering, and the elastic buffer 300 can drive the gear shifting lever 100 to rotate only after the input gear 200 rotates and the elastic buffer 300 deforms elastically to a certain extent, which helps to improve the smoothness of the gear shifting mechanism and the gear shifting of the transmission. And due to the buffering effect of the elastic buffer 300, when the gear shifting lever 100 is stuck, the input gear 200 can rotate by a certain angle relative to the gear shifting lever 100, so as to avoid the overload or sticking of the motor and the transmission mechanism of the gear shifting driving mechanism, and further reduce the risk of damage of the gear shifting driving mechanism and the transmission.

[0024] One of the connecting portions of the elastic buffer 300 is connected to or abuts against the first driving portion of the shift lever 100, and the other connecting portion of the elastic buffer 300 is connected to or abuts against the second driving portion of the input gear 200, so that the input gear 200 can drive the shift lever 100 to rotate through the elastic buffer 300.

[0025] With reference to Figure 2 And Figure 3 In some embodiments, the elastic buffer 300 is a torsion spring, which has a simple structure and is easy to manufacture. The elastic buffer 300 is sleeved on one end of the shift lever 100, and the torsion spring has a small volume, so that the overall shift mechanism occupies a small space and has a compact structure, and the elastic buffer 300 is easy to install on one end of the shift lever 100. The two ends of the torsion spring are two connecting portions, one end of the torsion spring is connected to or abuts against the shift lever 100, and the other end of the torsion spring is connected to or abuts against the input gear 200.

[0026] With reference to Figure 3 In some embodiments, the end of one end of the shift lever 100 is provided with a first clamping groove 110, and the input gear 200 is provided with a second clamping groove 210, the first clamping groove 110 and the second clamping groove 210 are respectively the first driving portion and the second driving portion, and the two connecting portions are respectively a first clamping head and a second clamping head, the first clamping head and the second clamping head are respectively clamped into the first clamping groove 110 and the second clamping groove 210, so that one of the connecting portions of the elastic buffer 300 is fixedly connected to the end of one end of the shift lever 100, and the other connecting portion of the elastic buffer 300 is fixedly connected to the input gear 200, so that the input gear 200 can drive the shift lever 100 to rotate through the elastic buffer 300.

[0027] With reference to Figure 3 In some embodiments, the side surface of the input gear 200 is provided with a receiving groove 240 in the shape of a ring, and the main body of the elastic buffer 300 is arranged in the receiving groove 240, so that the input gear 200 plays a role of receiving and protecting the elastic buffer 300, avoids the elastic buffer 300 from being excessively exposed, reduces the risk of interference between the elastic buffer 300 and other components of the transmission, and makes the structure of the shift mechanism more compact and the occupied space smaller.

[0028] See Figure 3 The groove bottom of the receiving groove 240 has a semicircular inclined surface portion extending from the groove bottom of the second clamping groove 210 to the side surface of the input gear 200, and one end of the torsion spring is attached to the inclined surface portion, so that the torsion spring can be prevented from shaking, the friction and wear between the input gear 200 and the torsion spring are reduced, and abnormal noise is reduced.

[0029] With reference to Figure 4In another embodiment, the input gear 200 is provided with a mounting hole 220, one end of the shift lever 100 is inserted into the mounting hole 220, the end of the shift lever 100 is provided with a limiting groove 120, the inner wall of the mounting hole 220 is provided with a limiting block 230, the limiting block 230 is inserted into the limiting groove 120, the two inner side walls of the limiting groove 120 opposite to the slot opening form an included angle a, the included angle a is 25° to 35°, the limiting block 230 has two mutually parallel outer side surfaces, and the two mutually parallel outer side surfaces of the limiting block 230 are respectively used for abutting against the two inner side walls of the limiting groove 120 opposite to the slot opening. The angle at which the input gear 200 can rotate relative to the shift lever 100 is less than the included angle a.

[0030] In some embodiments, the input gear 200 is provided with a mounting hole 220, one end of the shift lever 100 is inserted into the mounting hole 220, the end of the shift lever 100 is provided with a limiting groove 120, the inner wall of the mounting hole 220 is provided with a limiting block 230, the elastic buffer 300 can be block-shaped, the inner side wall of the limiting groove 120 is a first driving part, the outer side surface of the limiting block 230 is a second driving part, the elastic buffer 300 is arranged between the inner side wall of the limiting groove 120 and the outer side surface of the limiting block 230, and the elastic buffer 300 is in abutment or connection with the inner side wall of the limiting groove 120 and in abutment or connection with the outer side surface of the limiting block 230, that is, the elastic buffer 300 is arranged in the limiting groove 120 and the elastic buffer 300 wraps the limiting block 230. The elastic buffer 300 has elasticity, when the input gear 200 drives the limiting block 230 to rotate, the limiting block 230 will compress the elastic buffer 300 between the outer side surface of the limiting block 230 and the inner side wall of the limiting groove 120, and after the elastic buffer 300 between the outer side surface of the limiting block 230 and the inner side wall of the limiting groove 120 is elastically deformed to a certain extent, the limiting block 230 drives the shift lever 100 to rotate through the elastic buffer 300. It is conceivable that the elastic buffer 300 is made of an elastic material, such as rubber.

[0031] In some embodiments, the number of elastic buffers 300 is multiple, the multiple elastic buffers 300 are annularly distributed on the lateral side of the shift lever 100, the shift lever 100 is provided with multiple first driving parts, the input gear 200 is provided with multiple second driving parts, the multiple elastic buffers 300, the multiple first driving parts and the multiple second driving parts are one-to-one corresponding and matched, that is, the two connecting parts of one elastic buffer 300 are matched with one first driving part and one second driving part respectively. The one-to-one corresponding means that the multiple elastic buffers 300, the multiple first driving parts and the multiple second driving parts form multiple sets of matching mechanisms, and the multiple sets of matching mechanisms can all realize the transmission of torque. The annular distribution means that the central angles formed by any two adjacent elastic buffers 300 and the center of the cross section of the shift lever 100 are equal. The multiple first driving parts are annularly distributed on the shift lever 100, and the multiple second driving parts are also annularly distributed on the input gear 200.

[0032] The elastic buffer 300 can be a tension spring or a compression spring or an elastic block, the two ends of the tension spring or the compression spring or the elastic block are two connecting parts, one end of the tension spring or the compression spring or the elastic block is connected with or abuts against the first driving part, the other end of the tension spring or the compression spring or the elastic block is connected with or abuts against the second driving part, and the input gear 200 drives the shift lever 100 to rotate through the tension spring or the compression spring or the elastic block.

[0033] In another embodiment, referring to Figure 5 , the shift lever 100 is provided with multiple first protrusions 150, the multiple first protrusions 150 are annularly distributed with the central axis of the shift lever 100 as the center, the multiple first protrusions 150 are arranged radially on the shift lever 100, the first protrusion 150 is the first driving part, the input gear 200 is provided with multiple second protrusions 250, the multiple second protrusions 250 are annularly distributed with the central axis of the input gear 200 as the center, the second protrusion 250 is the second driving part, the number of the elastic buffer 300, the first protrusion 150 and the second protrusion 250 is equal, the multiple first protrusions 150 and the multiple second protrusions 250 are in the same plane, the first protrusion 150 and the second protrusion 250 are staggered, the elastic buffer 300 is between the first protrusion 150 and the second protrusion 250, and the two connecting parts of the elastic buffer 300 are connected (or abut) on the adjacent first protrusion 150 and second protrusion 250 respectively. The elastic buffer 300 can be a tension spring or a compression spring or an elastic block. The elastic buffer 300 is linear or arc-shaped. It can be conceived that the elastic buffer 300 is made of an elastic material, such as rubber.

[0034] When the input gear 200 carries the plurality of second protrusions 250 to rotate around the central axis of the shift lever 100, the second protrusions 250 pull or push the elastic buffer 300, the elastic buffer 300 pulls or pushes the first protrusion 150 to rotate around the central axis of the shift lever 100, thereby achieving driving the shift lever 100 to rotate.

[0035] With reference to Figure 3 The second clamping groove 210 is arranged on the inner side wall of the receiving groove 240 away from the central axis of the input gear 200, and the second clamping groove 210 penetrates or does not penetrate the outer tooth surface of the input gear 200. In another embodiment, with reference to Figure 6 The second clamping groove 210 is arranged on the side surface of the input gear 200, and the depth direction of the second clamping groove 210 is parallel to the axial direction of the input gear 200.

[0036] With reference to Figures 2 to 4 In some embodiments, the end of the shift lever 100 is provided with a limiting groove 120, and the input gear 200 is provided with a mounting hole 220, the input gear 200 is sleeved on the end of the shift lever 100 through the mounting hole 220, that is, the end of the shift lever 100 is arranged in the mounting hole 220, and the input gear 200, the mounting hole 220 and the shift lever 100 are coaxial.

[0037] The limiting block 230 is arranged in the limiting groove 120, so that the input gear 200 is kept synchronous rotation after rotating an angle relative to the shift lever 100. When the end of the shift lever 100 is arranged in the mounting hole 220, the limiting block 230 is arranged in the limiting groove 120, and when the limiting block 230 rotates with the input gear 200, the limiting block 230 abuts against the inner wall of the limiting groove 120, thereby achieving driving the shift lever 100 to rotate, so that the input gear 200 is kept synchronous rotation after rotating an angle relative to the shift lever 100.

[0038] It is conceivable that the size of the limiting groove 120 is larger than the size of the limiting block 230, so that the limiting block 230 abuts against the inner wall of the limiting groove 120 after rotating an angle relative to the shift lever 100, that is, the limiting block 230 abuts against the inner wall of the limiting groove 120 after a certain elastic deformation of the elastic buffer 300, thereby achieving driving the shift lever 100 to rotate by the input gear 200 through the limiting block 230 and the inner wall of the limiting groove 120, and ensuring that the input gear 200 can drive the shift lever 100 to rotate.

[0039] The normal working state of the gear shifting mechanism is that when the input gear 200 forces the elastic buffer 300 to deform, the elastic deformation range of the elastic buffer 300 limits the range of the rotation angle of the input gear 200 relative to the gear shifting lever 100. When the elastic buffer 300 fails or the gear shifting resistance borne by the gear shifting lever 100 is greater than the deformation force of the elastic buffer 300, the limiting block 230 abuts against the inner wall of the limiting groove 120, and the input gear 200 can forcibly drive the gear shifting lever 100 to rotate, thereby ensuring that the gear shifting mechanism and the transmission can be shifted.

[0040] In some embodiments, the input gear 200 can rotate 25° to 35° relative to the gear shifting lever 100. The rotation angle of the input gear 200 relative to the gear shifting lever 100 cannot be too small, so that the elastic buffer 300 can have sufficient buffering effect.

[0041] The rotation angle of the input gear 200 relative to the gear shifting lever 100 cannot be too large. When the gear shifting lever 100 rotates by an angle of one gear shift, the elastic buffer 300 returns to the initial state. Since the rotation angle of the input gear 200 relative to the gear shifting lever 100 cannot be too large, the gear shifting lever 100 and the corresponding transmission can be provided with a large number of gears, such as more than five gears.

[0042] It is conceived that the forward rotation starting angle refers to the relative rotation angle when the input gear 200 rotates forward to drive the gear shifting lever 100 to rotate forward, and the reverse rotation starting angle refers to the relative rotation angle when the input gear 200 rotates reversely to drive the gear shifting lever 100 to rotate reversely. The rotation angle range of the input gear 200 relative to the gear shifting lever 100 is the sum of the forward rotation starting angle and the reverse rotation starting angle.

[0043] In the embodiment, the input gear 200 can rotate 30° relative to the gear shifting lever 100, and the forward rotation starting angle and the reverse rotation starting angle are both 15°. Correspondingly, the gear shifting angle of the gear shifting mechanism and the corresponding transmission is 60°, that is, the gear shifting lever 100 rotates by 60°, and the corresponding transmission shifts gears once, and the transmission has five effective gears and one idle gear.

[0044] Reference Figure 4 In some embodiments, the two inner side walls opposite to each other of the slot of the limiting groove 120 are used to abut against the limiting block 230, the two inner side walls opposite to each other of the slot of the limiting groove 120 form an included angle α, and the included angle α is 25° to 35°, so that the input gear 200 can rotate 25° to 35° relative to the gear shifting lever 100.

[0045] Specifically, the width of the limiting groove 120 gradually decreases along the depth direction of the limiting groove 120, and the limiting block 230 has two mutually parallel outer sides, and the two mutually parallel outer sides of the limiting block 230 are respectively used to abut against the two inner side walls of the slot opposite to the slot of the limiting groove 120.

[0046] In the embodiment, the included angle α is 30°.

[0047] Referring to Figure 2 and Figure 3 In some embodiments, the first clamping groove 110 and the limiting groove 120 are distributed along the axial direction of the variable shift lever 100, and the first clamping groove 110 and the limiting groove 120 are connected, so as to facilitate simultaneous machining of the first clamping groove 110 and the limiting groove 120.

[0048] It is conceivable that the slot of the first clamping groove 110 and the slot of the limiting groove 120 are both formed on the outer circular surface of the variable shift lever 100, and the limiting groove 120 penetrates the end face of one end of the variable shift lever 100, so as to facilitate the connection of the one connecting part of the elastic buffer 300 through the limiting groove 120 and clamped into the first clamping groove 110, and facilitate the insertion of the limiting block 230 into the limiting groove 120.

[0049] Referring to Figures 7 to 11 , the transmission includes a clutch wheel 400 and a planetary gear train, the planetary gear train includes a sun gear 500, the axial directions of the clutch wheel 400 and the sun gear 500 are parallel to the axial direction of the variable shift lever 100, and one clutch wheel 400 and one sun gear 500 form a clutch mechanism.

[0050] It is further understood that the end face of the sun gear 500 is provided with a first end face ratchet gear, the first end face ratchet gear includes a plurality of first ratchet teeth 510, the plurality of first ratchet teeth 510 are distributed around the axis of the sun gear 500, and the first ratchet tooth 510 is provided with a first engagement surface 511; the end face of the clutch wheel 400 is provided with a second end face ratchet gear, the second end face ratchet gear includes a plurality of second ratchet teeth 410, the plurality of second ratchet teeth 410 are distributed around the axis of the clutch wheel 400, and the second ratchet tooth 410 is provided with a second engagement surface 411 for cooperating with the first engagement surface 511.

[0051] Referring to Figure 8 and Figure 9 , the first engagement surface 511 is sequentially provided with a first separation portion 5111, a first turning portion and a first inclined surface portion 5112 along the direction from the root of the first ratchet tooth 510 to the top of the first ratchet tooth 510, the first separation portion 5111 gradually extends along the opposite direction of the rotation of the clutch wheel 400 (the opposite direction of the arrow V in the figure) from the first turning portion to the root of the first ratchet tooth 510, and the first inclined surface portion 5112 gradually extends along the rotation direction of the clutch wheel 400 (the direction of the arrow V in the figure) from the top of the first ratchet tooth 510 to the first turning portion. Figure 8 and Figure 9 , the first engagement surface 511 is sequentially provided with a first separation portion 5111, a first turning portion and a first inclined surface portion 5112 along the direction from the root of the first ratchet tooth 510 to the top of the first ratchet tooth 510, the first separation portion 5111 gradually extends along the opposite direction of the rotation of the clutch wheel 400 (the opposite direction of the arrow V in the figure) from the first turning portion to the root of the first ratchet tooth 510, and the first inclined surface portion 5112 gradually extends along the rotation direction of the clutch wheel 400 (the direction of the arrow V in the figure) from the top of the first ratchet tooth 510 to the first turning portion.Figure 8 and Figure 9 When the second engagement surface 411 abuts against the first separation portion 5111, the sun gear 500 applies a separation force to the clutch gear 400 in the axial direction of the clutch gear 400 away from the sun gear 500, and when the second engagement surface 411 abuts against the first inclined surface portion 5112, the sun gear 500 applies a coupling force to the clutch gear 400 in the axial direction of the clutch gear 400 toward the sun gear 500.

[0052] Alternatively, referring to Figure 10 and Figure 11 , the second engagement surface 411 is provided with a second separation portion 4111, a second transition portion, and a second inclined surface portion 4112 in order from the root of the second ratchet tooth 410 to the top of the second ratchet tooth 410, the second separation portion 4111 gradually extends in the rotation direction of the clutch gear 400 (the direction of arrow V in FIG. 6) from the second transition portion to the root of the second ratchet tooth 410, and the second inclined surface portion 4112 gradually extends in the reverse rotation direction of the clutch gear 400 (the reverse direction of arrow V in FIG. 6) from the top of the second ratchet tooth 410 to the second transition portion, when the first engagement surface 511 abuts against the second separation portion 4111, the sun gear 500 applies a separation force to the clutch gear 400 in the axial direction of the clutch gear 400 away from the sun gear 500, and when the first engagement surface 511 abuts against the second inclined surface portion 4112, the sun gear 500 applies a coupling force to the clutch gear 400 in the axial direction of the clutch gear 400 toward the sun gear 500. Figure 10 and Figure 11 When the second engagement surface 411 abuts against the first separation portion 5111, the sun gear 500 applies a separation force to the clutch gear 400 in the axial direction of the clutch gear 400 away from the sun gear 500, and when the second engagement surface 411 abuts against the first inclined surface portion 5112, the sun gear 500 applies a coupling force to the clutch gear 400 in the axial direction of the clutch gear 400 toward the sun gear 500. Figure 10 and Figure 11 Alternatively, referring to

[0053] When the second engagement surface 411 abuts against the first separation portion 5111, the sun gear 500 applies a separation force to the clutch gear 400 in the axial direction of the clutch gear 400 away from the sun gear 500, and when the second engagement surface 411 abuts against the first inclined surface portion 5112, the sun gear 500 applies a coupling force to the clutch gear 400 in the axial direction of the clutch gear 400 toward the sun gear 500. Figure 9 , the first separation portion 5111 is a curved surface, the first inclined surface portion 5112 is a flat surface at an angle to the axial direction of the sun gear 500, and the first transition portion is a region between the first separation portion 5111 and the first inclined surface portion 5112. The first separation portion 5111 can be concave in the rotation direction of the sun gear 500 or can be convex in the reverse rotation direction of the sun gear 500. Referring to Figure 11 , the second separation portion 4111 is a curved surface, the second inclined surface portion 4112 is a flat surface at an angle to the axial direction of the clutch gear 400, and the second transition portion is a region between the second separation portion 4111 and the second inclined surface portion 4112. The second separation portion 4111 can be concave in the reverse rotation direction of the clutch gear 400 or can be convex in the rotation direction of the clutch gear 400.

[0054] Firstly, it needs to be understood that the rotation direction of the clutch wheel 400 and the sun wheel 500 is the same, and the gear shifting process of the transmission needs to change the clutch mechanism formed by the clutch wheel 400 and the sun wheel 500 from the closed state to the separated state or change the clutch mechanism formed by the clutch wheel 400 and the sun wheel 500 from the separated state to the closed state, that is, the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are separated or engaged. The larger resistance of the transmission during gear shifting mainly refers to the larger resistance required for the clutch wheel 400 to separate from the sun wheel 500, that is, the larger resistance during gear shifting when the clutch mechanism formed by the clutch wheel 400 and the sun wheel 500 changes from the closed state to the separated state.

[0055] The gear shifting driving mechanism drives the clutch wheel 400 to approach the sun wheel 500 through the gear shifting lever 100, and the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are engaged with each other. At this time, the clutch wheel 400 receives smaller gear shifting resistance; and when the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are separated, since the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are in the engaged state, the clutch wheel 400 and the sun wheel 500 change from the relatively static state to the relatively moving state, the static friction between the first ratchet teeth 510 and the second ratchet teeth 410 changes to the dynamic friction, and the friction resistance of the static friction is much larger than that of the dynamic friction. Therefore, a larger force needs to be applied to the clutch wheel 400 by the gear shifting lever 100 to make the clutch wheel 400 start to separate from the sun wheel 500, that is, the gear shifting lever 100 receives larger gear shifting resistance, and the transmission also has larger gear shifting resistance.

[0056] Referring to Figure 8 and Figure 9 , when the clutch wheel 400 and the sun wheel 500 are engaged with each other, the area on the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 abuts against the first separation part 5111, and the sun wheel 500 applies a separation force to the clutch wheel 400 along the axial direction of the clutch wheel 400 away from the sun wheel 500. As Figure 9The indicated force F1 is the normal pressure that the first separation part 5111 applies to the second engagement surface 411, that is, the normal pressure that the second engagement surface 411 receives, and the direction of F1 is perpendicular to the tangent of the first separation part 5111 along the direction T1 from the clutch wheel 400 to the sun wheel 500, and the direction of F1 is biased to the side of the clutch wheel 400. The separation force F that the clutch wheel 400 receives is equal to the component of F1 in the axial direction of the clutch wheel 400 minus the component of the static friction force that the clutch wheel 400 receives in the axial direction of the clutch wheel 400. When the shift lever 100 starts to drive the clutch wheel 400 to move away from the sun wheel 500, due to the existence of the separation force F, the shift lever 100 only needs to apply a small driving force to the clutch wheel 400 to drive the clutch wheel 400 to move away from the sun wheel 500, so that the area of the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 slides from the first separation part 5111 to the first inclined surface part 5112, and then the area of the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 slides from the first inclined surface part 5112 to the outside of the first engagement surface 511, and the clutch wheel 400 completes the disengagement from the sun wheel 500. Compared with the prior art, the size of the driving force that the shift lever 100 applies to the clutch wheel 400 is much smaller than the size of the original driving force of the prior art, and the gear shifting and operating the transmission can be more easily realized, the smoothness of the transmission is improved, and the riding experience of the bicycle is improved.

[0057] When the area of the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 is in abutment with the first inclined surface part 5112, the sun wheel 500 applies a joining force to the clutch wheel 400 along the axial direction of the clutch wheel 400 close to the sun wheel 500, which is beneficial to keep the sun wheel 500 and the clutch wheel 400 engaged, and avoids the clutch wheel 400 from automatically disengaging from the sun wheel 500, but this does not hinder the clutch wheel 400 from smoothly disengaging from the sun wheel 500, because when the clutch wheel 400 overcomes the static friction force to move, the clutch wheel 400 can use its own inertia and the driving of the shift lever 100 to smoothly disengage from the sun wheel 500.

[0058] In this embodiment, the second engagement surface 411 is a plane, and the second engagement surface 411 is parallel to the first inclined surface part 5112, so that the area of the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 can smoothly slide through the first separation part 5111 and the first inclined surface part 5112 in turn, and the area of the second engagement surface 411 away from the sun wheel 500 (the area of the second engagement surface 411 close to the tooth root of the second ratchet tooth 410) does not interfere with the first engagement surface 511. The area of the second engagement surface 411 close to the tooth top of the second ratchet tooth 410 is provided with a chamfer and / or a fillet.

[0059] In another embodiment, with reference to Figure 10 and Figure 11When the clutch wheel 400 and the sun wheel 500 mesh, the area near the tooth tip of the first ratchet 510 on the first meshing surface 511 abuts against the second separating part 4111, and the sun wheel 500 applies a separating force to the clutch wheel 400 along the axial direction of the clutch wheel 400, away from the sun wheel 500. Figure 11 The indicated force F2 is the normal force on the second separation part 4111. The direction of F2 is perpendicular to the tangent of the second separation part 4111 along the direction T2 from the sun gear 500 to the clutch gear 400. The direction of F2 is biased towards one side of the clutch gear 400. The separation force F on the clutch gear 400 is equal to the component of F2 in the axial direction of the clutch gear 400 minus the component of the static friction force on the clutch gear 400 in the axial direction of the clutch gear 400. When the shift lever 100 begins to drive the clutch wheel 400 away from the sun gear 500, due to the separation force F, the shift lever 100 only needs to apply a small driving force to the clutch wheel 400 to move it away from the sun gear 500. This causes the area on the first engagement surface 511 near the tip of the first ratchet 510 to slide from the second separation portion 4111 to the second inclined portion 4112. Then, the area on the first engagement surface 511 near the tip of the first ratchet 510 slides from the second inclined portion 4112 to the outside of the first engagement surface 511, and the clutch wheel 400 disengages from the sun gear 500. Compared with the prior art, the driving force applied by the shift lever 100 to the clutch wheel 400 is much smaller than the original driving force of the prior art, making it easier to shift gears and operate the gearbox, improving the smoothness of the gearbox and enhancing the riding experience of the bicycle.

[0060] When the area near the tooth tip of the first ratchet 510 on the first meshing surface 511 abuts against the second inclined surface 4112, the sun gear 500 applies a engagement force along the axial direction of the clutch gear 400 to the clutch gear 400, which helps the sun gear 500 and the clutch gear 400 to remain engaged and prevents the clutch gear 400 from automatically disengaging from the sun gear 500. However, this does not prevent the clutch gear 400 from smoothly disengaging from the sun gear 500, because when the clutch gear 400 moves against static friction, it can use its own inertia and the drive of the shift lever 100 to smoothly disengage from the sun gear 500.

[0061] The first engagement surface 511 is a flat surface, and the first engagement surface 511 is parallel to the second inclined surface portion 4112, so that the area of the first engagement surface 511 close to the tooth top of the first ratchet tooth 510 can smoothly slide through the second separation portion 4111 and the second inclined surface portion 4112 in sequence, and the area of the first engagement surface 511 away from the clutch 400 (the area of the first engagement surface 511 close to the tooth root of the first ratchet tooth 510) does not interfere with the second inclined surface portion 4112. The area of the first engagement surface 511 close to the tooth top of the first ratchet tooth 510 is provided with a chamfer and / or a fillet.

[0062] It should be noted that in the transmission, the clutch 400 is also limited by the spring in the transmission, so that the clutch 400 and the sun gear 500 are kept engaged, thereby avoiding the clutch 400 and the sun gear 500 from being separated automatically. The separation force applied by the sun gear 500 to the clutch 400 cannot make the clutch 400 automatically disengage from the sun gear 500, thereby avoiding the automatic separation of the clutch mechanism during operation, and the axial movement of the clutch 400 is ultimately controlled by the shift lever 100.

[0063] Referring to Figure 9 In some embodiments, the angle between the tangent direction T1 of the first separation portion 5111 and the axial direction of the sun gear 500 is an angle a, and the angle a is less than 60°.

[0064] F1 is the normal pressure of the first separation portion 5111 applied to the second engagement surface 411, f is the friction coefficient, and the friction coefficient f is taken as 0.5. When the angle a is 45°, the separation force F of the open clutch mechanism is F=F1×sin a-F1×f×cos a=0.355F1, that is, in the state that the clutch 400 and the sun gear 500 are engaged, the separation force received by the clutch 400 is 0.355 times the normal pressure, which helps the clutch 400 to overcome the static friction and move away from the sun gear 500. It should be noted that the angle a cannot be too large, otherwise the separation force will be too large, which will cause the sun gear 500 and the clutch 400 to be unable to keep together, and the angle a cannot be too small, otherwise the separation force will be too small, which will not help the clutch 400 to overcome the static friction and move away from the sun gear 500.

[0065] Similarly, referring to Figure 11 In some embodiments, the angle between the tangent direction T2 of the second separation portion 4111 and the axial direction of the clutch 400 is an angle b, and the angle b is less than 60°.

[0066] Referring to Figure 12In some of the embodiments, the outer surface of the shift lever 100 is provided with a first sliding groove 130, a first pin shaft is arranged in the first sliding groove 130, and when the shift lever 100 rotates, the two opposite inner walls of the first sliding groove 130 can drive the first pin shaft to move along the axial direction of the shift lever 100, and the first pin shaft is used to drive the clutch wheel 400 of the clutch mechanism to move along the axial direction of the shift lever 100, so as to separate or mesh the second ratchet teeth 410 of the clutch wheel 400 from the first ratchet teeth 510 of the sun gear 500 of the planetary gear train, that is, to complete the opening or closing of the clutch mechanism.

[0067] It can be understood that the outer surface of the shift lever 100 is provided with a second sliding groove 140, a second pin shaft is arranged in the second sliding groove 140, and the two opposite inner walls of the second sliding groove 140 are used to drive the second pin shaft to move along the axial direction of the shift lever 100, and the second pin shaft is used to drive the clutch wheel 400 of another clutch mechanism to move along the axial direction of the shift lever 100, so as to separate or mesh the second ratchet teeth 410 of the clutch wheel 400 of the other clutch mechanism from the first ratchet teeth 510 of another sun gear of the planetary gear train, that is, to complete the opening or closing of the other clutch mechanism.

[0068] It can be understood that the second inclined surface part 4112 can also be a curved surface with the same structure as the second separation part 4111, and the first inclined surface part 5112 can also be a curved surface with the same structure as the first separation part 5111.

[0069] The application also discloses a transmission, which comprises the above-mentioned shift mechanism and a transmission body. The transmission body is a prior art, and will not be described redundantly here. For example, the structures disclosed in the patent with the publication number CN116001967 and the name Bicycle Transmission Shift Trigger Mechanism and the patent with the publication number CN116161161 and the name Bicycle Internal Two-way Transmission and Transmission Control Method.

[0070] When the shift lever 100 is stuck, the input gear 200 can rotate by a certain angle relative to the shift lever 100, so as to avoid overloading or sticking of the motor and the transmission mechanism of the shift driving mechanism, the elastic buffer 300 plays a buffering role, reduces the risk of damage of the shift driving mechanism and the transmission, and a smaller force applied by the shift lever 100 can drive the clutch wheel 400 to move away from the sun gear 500, thereby improving the smoothness of the transmission shift.

[0071] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the description.

[0072] Of course, the present application is not limited to the above-described embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the present application, and these equivalent modifications or substitutions are included in the scope defined by the claims of the present application.

Claims

1. A gear shifting mechanism, characterized in that, include: The gear shift lever is equipped with a first drive unit; An input gear is used to mesh with the output gear of the gear shifting drive mechanism, and the input gear is provided with a second drive unit; The elastic buffer has two connecting parts. One connecting part connects to or abuts against the first driving part, and the other connecting part connects to or abuts against the second driving part. The input gear drives the gear shift lever to rotate through the elastic buffer to realize the gear shifting of the transmission.

2. The gear shifting mechanism according to claim 1, characterized in that, The elastic buffer is a torsion spring, which is sleeved on one end of the gear shift lever.

3. The shifting mechanism according to claim 1 or 2, characterized in that, The shift lever has a first slot at one end and a second slot on the input gear. The first slot and the second slot are the first drive part and the second drive part, respectively. The two connecting parts are respectively inserted into the first slot and the second slot.

4. The shifting mechanism according to claim 3, characterized in that, The shift lever has a limiting groove at one end, the input gear has a mounting hole, the inner wall of the mounting hole has a limiting block, and the limiting block passes through the limiting groove so that the input gear rotates synchronously with the shift lever after rotating at an angle.

5. The shifting mechanism according to claim 4, characterized in that, The first slot and the limiting slot are distributed along the axial direction of the shift lever, and the first slot and the limiting slot are connected.

6. The shifting mechanism according to claim 3, characterized in that, The input gear has an annular storage groove on its side, and the main body of the elastic buffer is located in the storage groove.

7. The gear shifting mechanism according to claim 6, characterized in that, The second slot penetrates the side wall of the receiving slot and the outer tooth surface of the input gear, or the second slot is opened on the side of the input gear, and the depth direction of the second slot is parallel to the axial direction of the input gear.

8. The gear shifting mechanism according to claim 1, characterized in that, The number of elastic buffers is multiple, and the multiple elastic buffers are distributed in a ring around the periphery of the gear shift lever. The gear shift lever is provided with multiple first drive parts, and the input gear is provided with multiple second drive parts. The multiple elastic buffers, the multiple first drive parts and the multiple second drive parts are in one-to-one correspondence and cooperation.

9. The gear shifting mechanism according to claim 1, characterized in that, The outer circular surface of the shift lever is provided with a first groove, and a first pin is inserted in the first groove. When the shift lever rotates, the two opposing inner walls of the first groove drive the first pin to move along the axial direction of the shift lever. The first pin is used to drive the clutch wheel of the clutch mechanism to move along the axial direction of the shift lever, so as to open or close the clutch mechanism.

10. A transmission, characterized in that, Includes the shifting mechanism and transmission body according to any one of claims 1 to 9.

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