Gear shift mechanism and transmission

Abstract

The application discloses a gear shifting mechanism and a transmission with the gear shifting mechanism, and the gear shifting mechanism comprises a gear shifting lever, an input gear and an elastic buffer, and the input gear is used for being engaged with an output gear of a gear shifting driving mechanism; the input gear drives the gear shifting lever to rotate through the elastic buffer, so as to realize gear shifting of the transmission. Since the elastic buffer has the ability of elastic deformation, the elastic buffer has the functions of force storage and buffering, and after the elastic buffer is deformed elastically, the elastic buffer can drive the gear shifting lever to rotate, so that the smoothness of gear shifting of the gear shifting mechanism and the transmission is improved. Moreover, due to the buffering effect of the elastic buffer, when the gear shifting lever is stuck, the input gear can rotate by a certain angle relative to the gear shifting lever, so that the motor and the transmission mechanism of the gear shifting driving mechanism are prevented from being overloaded or stuck, and the risk of damage of the gear shifting driving mechanism and the transmission 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, the shifting is achieved. At present, 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, thereby easily causing the jamming of the shifting mechanism and the damage of the shifting drive mechanism. 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 shifting of the derailleur.

[0006] At least has the following beneficial effects:

[0007] 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 to a certain extent, the elastic buffer can drive the shifting lever to rotate, which helps to improve the smoothness of the shifting mechanism and the derailleur shifting. Moreover, 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 further reducing the risk of damage to the shifting drive mechanism and the derailleur.

[0008] 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.

[0009] 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.

[0010] 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.

[0011] 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.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] At least has the following beneficial effects:

[0018] 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.

[0019] Additional aspects and advantages of the present application will be made apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0020] The present application will be further described with reference to the drawings and examples, wherein:

[0021] Figure 1 is a structural schematic view of one of the embodiments of the present application;

[0022] Figure 2 is a partial exploded view of one of the embodiments of the present application;

[0023] Figure 3 is a partial exploded view of two of the embodiments of the present application;

[0024] Figure 4 is a side structural schematic view of one of the embodiments of the present application;

[0025] Figure 5 is a sectional structural schematic view of the input gear, the elastic buffer, the shift lever, the first protrusion and the second protrusion of one of the embodiments of the present application;

[0026] Figure 6 is a structural schematic view of the input gear of one of the embodiments of the present application;

[0027] Figure 7 is a structural schematic view of the clutch wheel, the sun gear and the main shaft of one of the embodiments of the present application;

[0028] Figure 8 is a sectional structural schematic view of the sun gear and the clutch wheel of one of the embodiments of the present application when they are engaged with each other;

[0029] Figure 9 is a sectional structural schematic view of the clutch wheel of one of the embodiments of the present application;

[0030] Figure 10 is a sectional structural schematic view of the sun gear and the clutch wheel of another embodiment of the present application when they are engaged with each other;

[0031] Figure 11 is a sectional structural schematic view of the clutch wheel of another embodiment of the present application;

[0032] Figure 12 is a structural schematic view of another embodiment of the shift lever of the present application;

[0033] BRIEF DESCRIPTION OF DRAWINGS

[0034] shift lever 100, first clamping slot 110, limiting slot 120, first sliding slot 130, second sliding slot 140, first protrusion 150;

[0035] The input gear 200, the second clamping slot 210, the mounting hole 220, the limiting block 230, the receiving slot 240, and the second protruding block 250;

[0036] The elastic buffer 300;

[0037] The clutch wheel 400, the second ratchet tooth 410, the second meshing surface 411, the second separation part 4111, and the second inclined surface part 4112;

[0038] The sun gear 500, the first ratchet tooth 510, the first meshing surface 511, the first separation part 5111, and the first inclined surface part 5112;

[0039] The main shaft 600. DETAILED DESCRIPTION

[0040] 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, etc. 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 does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0041] In the description of the present application, if the first and second are described, they are only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the sequence of technical features indicated.

[0042] In the description of the present application, unless otherwise explicitly limited, the words such as setting, mounting, connecting, etc. 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.

[0043] 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, wherein the gear shifting lever 100 is provided with a first driving part; the input gear 200 is used to be engaged with an 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; 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.

[0044] 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 through the second driving part, the elastic buffer 300 and the first driving part in turn, the input gear 200 drives the gear shifting lever 100 to rotate through the elastic buffer 300, so that the gear shifting of the transmission is realized. 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, so that the smoothness of the gear shifting mechanism and the gear shifting of the transmission is improved. Moreover, due to the buffering effect of the elastic buffer 300, the input gear 200 can rotate by a certain angle relative to the gear shifting lever 100 in the state that the gear shifting lever 100 is stuck, so that the motor and the transmission mechanism of the gear shifting driving mechanism are prevented from being overloaded or stuck, and the risk of damage of the gear shifting driving mechanism and the transmission is reduced.

[0045] One connecting part of the elastic buffer 300 is connected or abuts against the first driving part of the gear shifting lever 100, and the other connecting part of the elastic buffer 300 is connected or abuts against the second driving part of the input gear 200, so that the input gear 200 can drive the gear shifting lever 100 to rotate through the elastic buffer 300.

[0046] 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 gear shifting lever 100, the torsion spring has a small volume, so that the gear shifting mechanism occupies a small space and has a compact structure, and the elastic buffer 300 is easy to install on one end of the gear shifting lever 100. The two end heads of the torsion spring are two connecting parts, one end head of the torsion spring is connected or abuts against the gear shifting lever 100, and the other end head of the torsion spring is connected or abuts against the input gear 200.

[0047] With reference to Figure 3 In some embodiments, the end head of one end of the gear shifting lever 100 is provided with a first clamping groove 110, 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 part and the second driving part, the two connecting parts 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 connecting part of the elastic buffer 300 is fixedly connected with the end head of one end of the gear shifting lever 100, and the other connecting part of the elastic buffer 300 is fixedly connected with the input gear 200, so that the input gear 200 can drive the gear shifting lever 100 to rotate through the elastic buffer 300.

[0048] With reference to Figure 3In some embodiments, the side of the input gear 200 is provided with a ring-shaped receiving groove 240, and the main body of the elastic buffer 300 is arranged in the receiving groove 240. The input gear 200 serves to receive and protect 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 gear shifting mechanism more compact and occupies less space.

[0049] Referring to Figure 3 The bottom of the receiving groove 240 is provided with a semi-annular inclined surface portion extending from the bottom of the second clamping groove 210 to the side of the input gear 200. One end of the torsion spring is attached to the inclined surface portion, which can avoid the torsion spring from shaking, reduce the friction and wear between the input gear 200 and the torsion spring, and reduce the abnormal noise.

[0050] Referring to Figure 4 In another embodiment, the input gear 200 is provided with a mounting hole 220, and one end of the gear shifting lever 100 is arranged in the mounting hole 220. The end of the gear shifting lever 100 is provided with a limiting groove 120, and the inner wall of the mounting hole 220 is provided with a limiting block 230. The limiting block 230 is arranged in the limiting groove 120, and the two inner side walls of the limiting groove 120 form an included angle a. The included angle a is 25° to 35°, and the limiting block 230 has two mutually parallel outer side surfaces. The two mutually parallel outer side surfaces of the limiting block 230 are respectively arranged against the two inner side walls of the limiting groove 120. The angle of rotation of the input gear 200 relative to the gear shifting lever 100 is less than the included angle a.

[0051] In some embodiments, the input gear 200 is provided with a mounting hole 220, and one end of the gear shifting lever 100 is arranged in the mounting hole 220. The end of the gear shifting lever 100 is provided with a limiting groove 120, and 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 portion, and the outer side surface of the limiting block 230 is a second driving portion. 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 the outer side surface of the limiting block 230, that is, the elastic buffer 300 is arranged in the limiting groove 120 and 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. 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 gear shifting lever 100 to rotate through the elastic buffer 300. It can be envisaged that the elastic buffer 300 is made of an elastic material, such as rubber.

[0052] 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 an elastic buffer 300 are matched with a first driving part and a second driving part respectively. 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 torque transmission. 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.

[0053] 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.

[0054] 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 buffers 300, the first protrusions 150 and the second protrusions 250 is equal, the multiple first protrusions 150 and the multiple second protrusions 250 are in the same plane, the first protrusions 150 and the second protrusions 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.

[0055] 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.

[0056] With reference to Figure 3 , the second clamping groove 210 is opened 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 opened 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.

[0057] 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.

[0058] 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.

[0059] 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 elastic buffer 300 is elastically deformed, 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] It is conceivable 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.

[0064] In this 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 once, and the transmission has five effective gears and one idle gear.

[0065] 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.

[0066] 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.

[0067] In the embodiment, the included angle α is 30°.

[0068] With reference to Figure 2 and Figure 3 In some of the embodiments, the first clamping groove 110 and the limiting groove 120 are distributed along the axial direction of the 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.

[0069] 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 shift lever 100, and the limiting groove 120 penetrates the end face of one end of the 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.

[0070] With reference to Figures 7 to 11 , the transmission comprises a clutch wheel 400 and a planetary gear train, the planetary gear train comprises 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 shift lever 100, and one clutch wheel 400 and one sun gear 500 form a clutch mechanism.

[0071] 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 comprises 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 meshing 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 comprises 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 meshing surface 411 for cooperating with the first meshing surface 511.

[0072] With reference to Figure 8 and Figure 9 , the first meshing 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 dedendum of the first ratchet tooth 510 to the cusp of the first ratchet tooth 510, the first separation portion 5111 gradually extends along the reverse direction of the rotation of the clutch wheel 400 (the reverse direction of the arrow V in the figure) from the first turning portion to the dedendum 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 cusp of the first ratchet tooth 510 to the first turning portion. Figure 8 and Figure 9 , the first meshing 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 dedendum of the first ratchet tooth 510 to the cusp of the first ratchet tooth 510, the first separation portion 5111 gradually extends along the reverse direction of the rotation of the clutch wheel 400 (the reverse direction of the arrow V in the figure) from the first turning portion to the dedendum 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 cusp of the first ratchet tooth 510 to the first turning portion.Figure 8 and Figure 9 Extending in the direction of the middle arrow V, when the second engagement surface 411 abuts against the first separation part 5111, the sun gear 500 applies a separation force to the clutch gear 400 along the axial direction of the clutch gear 400 away from the sun gear 500. When the second engagement surface 411 abuts against the first inclined part 5112, the sun gear 500 applies an engagement force to the clutch gear 400 along the axial direction of the clutch gear 400 close to the sun gear 500.

[0073] Or, refer to Figure 10 and Figure 11 The second meshing surface 411 is provided with a second separating portion 4111, a second turning portion, and a second inclined portion 4112 in sequence along the direction from the root of the second ratchet 410 to the tip of the second ratchet 410. The second separating portion 4111 gradually moves from the second turning portion to the root of the second ratchet 410 along the rotation direction of the clutch wheel 400. Figure 10 and Figure 11 (in the direction of the middle arrow V) extends, and the second inclined portion 4112 gradually moves from the tip of the second ratchet 410 to the second turning point in the opposite direction of the rotation of the clutch wheel 400 ( Figure 10 and Figure 11 Extending in the opposite direction of the middle arrow V, when the first engagement surface 511 abuts against the second separation part 4111, the sun gear 500 applies a separation force to the clutch gear 400 along the axial direction of the clutch gear 400 away from the sun gear 500. When the first engagement surface 511 abuts against the second inclined part 4112, the sun gear 500 applies an engagement force to the clutch gear 400 along the axial direction of the clutch gear 400 close to the sun gear 500.

[0074] Reference Figure 9 The first separating portion 5111 is a curved surface, the first inclined portion 5112 is a plane forming an angle with the axis of the sun gear 500, and the first turning portion is the transition area between the first separating portion 5111 and the first inclined portion 5112. The first separating portion 5111 may be concave in the direction of rotation of the sun gear 500 or convex in the opposite direction of rotation of the sun gear 500. (Refer to...) Figure 11 The second separating portion 4111 is a curved surface, the second inclined portion 4112 is a plane that forms an angle with the axis of the clutch wheel 400, and the second turning portion is the transition area between the second separating portion 4111 and the second inclined portion 4112. The second separating portion 4111 may be concave in the opposite direction of the rotation of the clutch wheel 400 or convex in the direction of the rotation of the clutch wheel 400.

[0075] 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 gear shifting resistance of the transmission is mainly the resistance required when the clutch wheel 400 is separated from the sun wheel 500, that is, the gear shifting resistance of the clutch mechanism formed by the clutch wheel 400 and the sun wheel 500 from the closed state to the separated state.

[0076] 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 gear shifting resistance of the clutch wheel 400 is small; when the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are separated, the first plurality of ratchet teeth 510 and the second plurality of ratchet teeth 410 are in the state of mutual engagement, the clutch wheel 400 and the sun wheel 500 change from the relative static state to the relative 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 resistance of the gear shifting lever 100 is large, and the gear shifting resistance of the transmission is also large.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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°.

[0085] 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.

[0086] 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°.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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 drive mechanism, the elastic buffer 300 plays a buffering role, reduces the risk of damage of the shift drive 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.

[0092] 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 present application.

[0093] 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 shift mechanism, characterized by The application relates to a gear shifting mechanism and a gear shifting device. The gear shifting mechanism comprises a gear shifting lever, a first driving part, an input gear, a second driving part, an elastic buffer and a gear shifting device body. The gear shifting lever is provided with a first clamping groove at one end, and the input gear is provided with a second clamping groove. The gear shifting lever is provided with a limiting groove at one end, and the input gear is provided with a limiting block. The elastic buffer is a torsion spring, and the elastic buffer is sleeved on one end of the gear shifting lever. The first clamping groove and the limiting groove are distributed along the axial direction of the gear shifting lever and are connected.

2. The shift mechanism according to claim 1, characterized in that The input gear is provided with an annular receiving groove on the side surface.

3. The shift mechanism according to claim 1, characterized by 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.

4. The shift mechanism according to claim 1, characterized by The outer circular surface of the gear shifting lever is provided with a first sliding groove, and a first pin shaft is arranged in the first sliding groove.

5. The shift mechanism according to claim 4, characterized in that The gear shifting mechanism and the gear shifting device body are arranged in the gear shifting device.

6. The shift mechanism according to claim 1, characterized by The gear shifting mechanism and the gear shifting device body are arranged in the gear shifting device.

7. Transmission, characterized in that ​

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