Flexible driving mandrel and gear adjusting device

Abstract

The utility model relates to the technical field of transmissions, in particular to a flexible driving mandrel and a gear adjusting device.The flexible driving mandrel comprises a mandrel body and a plurality of positioning bosses arranged on the outer wall of the mandrel body in the axial direction, and gear driving blocks corresponding to the positioning bosses in position and number are arranged on the mandrel body in a sleeved mode; the adjacent gear driving blocks and the adjacent positioning bosses are evenly distributed in the circumferential direction of the mandrel in an angle mode. An avoiding notch matched with the positioning boss is formed in the edge of a center hole of the gear driving block and is used for providing a swingable gap for the positioning boss; a clamping groove is formed in the outer edge of the gear driving block; and one end of the torsion spring is fixed on the mandrel, and the other end of the torsion spring is clamped on the gear driving block. According to the invention, heavy-load gear-up and light-load gear-down can be realized without stopping feet, power loss caused in the gear-shifting process can be avoided, the gear-shifting process is more flexible, riding is more comfortable, and high-low gear switching is rapid and stable.

Description

Technical Field

[0001] The utility model relates to the technical field of transmissions, in particular to a flexible driving spindle and a gear position adjusting device. Background Art

[0002] When riding a bicycle, you need to change gears all the time when passing through different sections of the road to keep the input minimal and obtain the power that matches the current optimization.

[0003] Existing bicycle transmissions are divided into two categories: external transmissions and internal transmissions. External transmissions are a common speed change method with a simple structure and light weight. They use an open chain mechanism as a transmission system and achieve different chain transmission ratios by moving the chain to different toothed discs or flywheels. External transmissions do not need to stop pedaling (no need to stop) during the process of upshifting, and do not need to stop when going downhill on a flat road. However, when the transmission is overloaded on a steep slope, it is necessary to reduce the frequency of pedaling (reduce the pedaling frequency) to reduce the gear. However, the process of shifting the chain to different toothed discs in traditional external transmissions has a response delay and sluggishness. For example, when encountering a traffic light, it takes a certain distance to reduce the gear from a high gear to a low gear, which does not achieve the effect that current riders want. Therefore, external transmissions are difficult to meet the riding comfort and operating experience in complex sections. In addition, the components of the external transmission are exposed and relatively easy to be contaminated. There are disadvantages such as loud noise and easy chain detachment during the gear shifting process.

[0004] The internal transmission of a bicycle adopts a fully enclosed system of tooth engagement, which has the advantages of small size, high transmission efficiency, strong load capacity, dust and water resistance, etc. The main structure includes a core shaft, an input mechanism, an output mechanism, a planetary gear mechanism and a shifting mechanism, etc. The shifting mechanism realizes the transmission path of gears with different gear ratios by changing the transmission between different gears. When the rider steps on the pedal, the force is transmitted to the input mechanism. At this time, the pull rope mechanism, under the operation of the rider, will toggle the planetary gear mechanism to rotate a certain angle, drive the shifting mechanism, make the corresponding gears clutch, change the transmission path between the gears, realize different transmission ratios, and transmit the force to the bicycle tooth plate (sprocket) and chain through the output mechanism, so as to realize the speed change effect of different gears. Compared with the external transmission, the internal transmission can achieve the advantages of smooth shifting, no noise, and second shifting.

[0005] There are three situations in the existing internal transmission structure design: 1. You need to stop your foot during the process of shifting up and down; 2. You can shift up without stopping your foot, but you must stop your foot when shifting down; 3. In the process of downshifting, you not only need to stop your foot, but also step on the pedal in the opposite direction at a certain angle (backwards). During the process of stopping your foot and backing your foot, power loss and speed reduction will occur, and it will be laborious to start again, which affects the comfort and experience of riding, and cannot achieve the effect of shifting up and down of the external transmission.

[0006] Therefore, there is an urgent need in the art to propose a new type of speed change device to solve the above limitations of the prior art transmission. Utility Model Content

[0007] In order to solve the problems in the prior art of corresponding delays in transmission shifting, difficulty in meeting the needs of complex roads, the need to stop during upshifting or downshifting, resulting in power loss and poor riding experience, the utility model provides a flexible drive spindle and a gear adjustment device, which has the characteristics of being able to upshift with heavy loads without stopping and downshift with light loads without stopping, providing a good riding experience.

[0008] A flexible driving core shaft comprises a core shaft and a plurality of positioning bosses arranged axially on the outer wall of the core shaft, a gear driving block corresponding to the position and number of the positioning bosses is mounted on the core shaft, and adjacent gear driving blocks and adjacent positioning bosses are evenly distributed along the circumference of the core shaft at an angle; the gear driving block is provided with a clearance notch matched with the positioning boss on the edge of its own center hole, which is used to provide a swingable gap for the positioning boss; the outer edge of the gear driving block is arc-shaped, and a clamping groove is provided on the outer edge; and a torsion spring is also included, one end of which is fixed on the core shaft, and the other end is clamped on the gear driving block.

[0009] Furthermore, the angle between adjacent positioning bosses along the circumference of the core shaft is 40-90 degrees.

[0010] Furthermore, the clearance gap is fan-shaped, and the central angle of the fan-shaped arc hole is 360° / N, where N is the number of gears; or, when N is 6 or less than 5, the central angles of the fan-shaped and arc-shaped holes are both 60°, 72° or 52°.

[0011] Furthermore, the gear driving block is sleeved on the core shaft and is limited left and right by a limiting member.

[0012] Furthermore, the outer edge of the gear driving block is arc-shaped.

[0013] To achieve the above-mentioned purpose, the utility model also provides a gear adjustment device, including the above-mentioned flexible driving core shaft, and also includes a sleeve, the core shaft is axially installed inside the sleeve and is rotatably connected to the sleeve; the sleeve is provided with an installation groove corresponding to the number and position of the gear driving blocks, and a pawl matching the slot is provided in the installation groove, the middle part of the pawl is rotatably set in the installation groove, and an elastic member is connected between the bottom of one end of the pawl and the installation groove, which is used to bounce up the end and extend the bottom of the other end of the pawl into the rotation path of the slot.

[0014] Furthermore, the number of the ratchets is more than two, and adjacent ratchets are arranged opposite to each other at 180 degrees.

[0015] Furthermore, the pawl is cross-shaped, a gasket is mounted on the shaft sleeve, and two sides of the pawl are rotatably mounted in the mounting groove through the gasket.

[0016] Furthermore, a gear-increasing device which can slide along the axial direction of the core shaft is mounted on one end of the core shaft; a gear-increasing device is provided on the gear-increasing device, and when the core shaft is rotated to an angle matching with the gear-increasing device, the gear-increasing device can move linearly along the axial direction of the core shaft; a ratchet which matches with the gear-increasing device is provided on the sleeve at a position corresponding to the gear-increasing device.

[0017] Furthermore, a sliding groove is provided on the side wall at one end of the core shaft along the axial direction, and the gear-increasing device is mounted on the core shaft at a position corresponding to the sliding groove; a limiting rod is installed on the outer side of the gear driving part, and the limiting rod extends into the sliding groove; the side walls of the gear-increasing device from the inner end to the outer end are successively provided with a gear driving part, a gear-increasing ring groove and a rotating groove, and a driving groove is provided on the side of the gear driving part; the rotating groove includes more than two arc grooves extending circumferentially along the outer side of the gear-increasing sleeve, and the tail of the arc groove is connected to the starting point of the adjacent arc groove through an oblique groove; a sliding rod is vertically provided on the sleeve, and the sliding rod extends into the rotating groove; when the core shaft is rotated to an angle matching the gear-increasing device, the rotating groove can make the gear-increasing device move along the sliding groove under the joint action of the limiting rod and the sliding rod.

[0018] Furthermore, the central angle of the arc groove is 360°(n-1) / n, where n is the number of gears. When the sliding rod slides into the adjacent arc groove through the inclined groove, the moving distance of the shift-increasing sleeve is equal to the center distance between the two corresponding arc grooves.

[0019] Furthermore, a first planetary gear set and a second planetary gear set are installed at one end of the core shaft; the first planetary gear and the second planetary gear share a planetary bracket; the sun gear 1 in the first planetary gear set is connected to the shaft sleeve as a whole, and the sun gear 1 is rotatably connected to the core shaft; the ring gear 1 in the first planetary gear set is rotatably connected to the shaft sleeve; the sun gear 2 in the second planetary gear set is keyed to the core shaft, and the ring gear 2 in the second planetary gear set is sleeved on the outside of the ring gear 1 in the first planetary gear set; the ring gear 2 is transmission-connected with a gear shifting device, a gear shifting button is fixed at the other end of the core shaft, and a gear position mark is provided at the end of the sleeve corresponding to the gear shifting button.

[0020] Furthermore, a rope groove is provided on the outer side of the second ring gear in the second planetary gear set, and the gear shifting device is a gear shifting rope wound around the ring groove.

[0021] Furthermore, the gear shifting device is a control motor, which is transmission-connected to the second gear ring and is used to drive the second gear ring to rotate.

[0022] Furthermore, one or more positioning grooves are provided on the inner side of one end of the sleeve, and an elastic clamp matching the positioning groove is correspondingly provided on the core shaft, and the elastic clamp can enter or leave the positioning groove when the core shaft rotates.

[0023] The beneficial effects of the utility model are:

[0024] 1. The utility model uses an ingenious mechanical matching transmission principle, and has the advantages of fast gear shifting, high transmission efficiency, wide speed ratio, upshifting under heavy load, downshifting under light load, and arbitrary shifting, etc., which makes up for the shortcomings of traditional external transmissions.

[0025] 2. It can realize upshifting under heavy load and downshifting under light load without stopping, which can avoid power loss caused by the gear shifting process, making the gear shifting process smoother and riding more comfortable. Under heavy and light load road conditions, the high and low gear switching is fast and stable.

[0026] 3. When the pull rope for switching gears is used for a long time, the pull rope will become longer, which will cause inaccurate gear switching. This solution can rotate the core shaft through the gear adjustment knob and quickly restore to the gear corresponding to the pull rope length through the gear mark.

[0027] 4. When using a gear-increasing sleeve, the gears can be doubled, which improves riding comfort while keeping the size small. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the structure of the flexible drive mandrel of the utility model;

[0029] Figure 2 for Figure 1 A schematic diagram of the structure from another perspective;

[0030] Figure 3 for Figure 1 A schematic diagram of the structure from another perspective;

[0031] Figure 4 Another structural schematic diagram of the flexible drive mandrel of the utility model;

[0032] Figure 5 for Figure 4 A schematic diagram of the structure from another perspective;

[0033] Figure 6 It is a structural schematic diagram of the mandrel and the positioning boss;

[0034] Figure 7 is a schematic diagram of the structure of the gear-increasing device;

[0035] Figure 8 for Figure 7 A schematic diagram of the structure from another perspective;

[0036] Fig. 9 It is a structural schematic diagram of the gear drive block;

[0037] Fig.10 It is a schematic diagram of the structure of the flexible driving mandrel and the pawl;

[0038] Fig.11 It is a schematic diagram of the structural assembly of the flexible driving mandrel and the pawl;

[0039] Fig.12 It is a structural schematic diagram of the speed-changing regulating device;

[0040] Fig.13 A schematic diagram of an internal gear structure of a transmission;

[0041] Fig.14 for Fig.13 sectional view of

[0042] Fig.15 The figure is the external structure diagram of the transmission;

[0043] Fig.16 It is a schematic diagram of the structure of the positioning groove and the elastic clamp;

[0044] Fig.17 for Fig.16 AA section view;

[0045] In the figure: 1, mandrel; 2, positioning boss; 3, gear drive block; 4, clearance notch; 5, opening groove 6, gasket; 7, clamping groove; 8, torsion spring; 9, shaft sleeve; 10, mounting groove; 11, ratchet; 12, elastic member; 13, gear-increasing device; 14, gear drive unit; 15, slide groove; 16, limit rod; 17, gear-increasing ring groove; 18, rotating groove; 20, arc groove; 21, inclined groove; 22, sliding rod; 23, first planetary gear set; 2301, sun gear one; 2302, planetary gear one; 2303, planetary carrier; 2304, ring gear one; 24, second planetary gear set; 2401, sun gear two; 2402, planetary gear two; 2403, ring gear two; 2404, rope groove; 25, shift knob; 26, gear position mark; 27, positioning groove; 28, elastic clip; 29, limiter; 30, shift gear; 31, input shaft; 32, output gear shaft; 33, output gear; 34, input gear; 35, chainring; 36, transmission housing; 37, bearing; 38, pull rope. DETAILED DESCRIPTION

[0046] The following is a further description of a flexible driving spindle and a gear adjustment device of the utility model in conjunction with specific embodiments.

[0047] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, a flexible driving spindle comprises a spindle 1 and a plurality of positioning bosses 2 axially arranged along the outer wall of the spindle 1, a gear driving block 3 corresponding to the position and number of the positioning bosses 2 is mounted on the spindle 1, and adjacent gear driving blocks 3 and adjacent positioning bosses 2 are uniformly distributed along the circumference of the spindle 1 at an angle; the gear driving block 3 is provided with a clearance notch 4 matched with the positioning boss 2 at the edge of its own center hole, which is used to provide a swingable gap for the positioning boss 2; the outer edge of the gear driving block 3 is arc-shaped, and a clamping groove 7 is provided on the outer edge; and a torsion spring 8 is also included, one end of the torsion spring 8 is fixed on the spindle 1, and the other end is clamped on the gear driving block 3.

[0048] The positioning boss 2 is used to cooperate with the gear drive block 3 to realize upshifting and downshifting under load. In this solution, the gear drive block 3 is an arc-shaped structure with a slot 7. The outer surface of the arc-shaped structure can be a circular arc or an elliptical arc, so that one end of the pawl 11 can slide on the outer surface of the gear drive block 3 under the action of the elastic member 12. In order to ensure that the pawl 11 does not jump, the arc outer surface is optimal. The slot 7 is an arc-shaped recessed portion on the outer edge of the gear drive block 3, so that when one end of the pawl slides into the arc-shaped recessed portion, the other end can be bounced up by the elastic member and engaged with the corresponding shift gear. In other embodiments, the slot 7 can also be other shapes, so that the pawl 11 can be easily engaged with the slot and can be easily disengaged.

[0049] A plug hole is provided on the core shaft 1, and an opening slot 5 is provided on the corresponding gear drive block 3; two ends of the torsion spring 8 are respectively inserted into the opening slot 5 on the core shaft 1 and the gear drive block 3; the opening slot 5 is convenient for installing the torsion spring 8.

[0050] Since this structure does not have a clutch, the combination of the gear drive block 3 and the torsion spring is used to shift gears under load. When the core shaft 1 starts to rotate and shift gears, the next gear can be engaged while the currently engaged gear remains unchanged. Since shifting gears is a speed-increasing process, after the next gear is engaged, the previous gear is automatically reset under the action of the gear drive block 3 and the torsion spring 8.

[0051] Better, such as Fig. 9 As shown, the clearance gap 4 is fan-shaped, and the central angle of the fan-shaped arc hole is 360° / N, where N is the number of gears. The angle is related to the gear, and 360° can be divided equally according to the number of gears, such as 9 gears, the central angle of the clearance gap 4 is 40°; 8 gears, the central angle of the clearance gap 4 is 45°; 6 gears, the central angle of the clearance gap 4 is 60°; 5 gears, the central angle of the clearance gap 4 is 72°; 4 gears, the central angle of the clearance gap 4 is 90°; 7 gears, about 52°. Or when there are six gears or less than five gears, the central angle of the clearance gap 4 can also be fixed at an angle (such as 60°, 72°, 52°). The arc length of the clearance gap is greater than half the arc length of the slot of the gear drive block 3, that is, when the outer end of the positioning boss 2 rotates the arc length of the clearance gap, the pawl 11 corresponding to the next gear can slide out of the slot of the corresponding gear drive block 3, that is, the arc-shaped recessed portion.

[0052] Better, such as Figure 6As shown, the angle between adjacent positioning bosses 2 along the circumference of the core shaft 1 is 40-90 degrees. The angle between adjacent positioning bosses 2 in the circumferential direction is related to the gear position, so that when the core shaft 1 rotates to this angle, the positioning boss 2 can drive the gear drive block 3, and the pawl 11 at a certain position can slide into the arc-shaped recessed portion of the corresponding gear drive block 3. For example, when there are six gears, the angle between adjacent positioning bosses 2 in the circumferential direction of the core shaft 1 is 60°; when there are eight gears, the angle between adjacent positioning bosses 2 in the circumferential direction of the core shaft 1 is 45°. In this scheme, the preferred angles between adjacent positioning bosses 2 are 60°, 72°, and 45°.

[0053] Preferably, the pawl 11 is cross-shaped, and the corresponding mounting groove 10 is also a cross-shaped groove. The mounting groove 10 has groove bottoms on both sides of the axial direction, and a groove bottom is provided on one radial side for mounting the elastic member, and the other radial side is hollowed out, so that one end of the pawl can be rotated downward and extended into the arc-shaped recessed portion of the gear drive block 3. The bushing 9 is provided with a gasket 6, and both sides of the pawl 11 are rotatably mounted in the mounting groove 10 through the gasket 6. The fixing of the pawl abandons the traditional fixing method by bolts, which can avoid the risk of the bolts falling into the inside of the device and help to improve the service life.

[0054] Better, such as Figure 2 As shown, the gear drive block 3 is sleeved on the core shaft 1 and is limited left and right by the limiter 29. In this embodiment, an annular groove is provided on the left and right sides of the core shaft 1, and the limiter 29 is a thin clamp, which is sleeved on the core shaft 1 and placed in the annular groove.

[0055] The flexible driving mandrel in this scheme is suitable for transmissions, and is suitable for gear switching and speed change of vehicles such as bicycles, cars, motorcycles, and electric vehicles, and is particularly suitable for bicycle transmissions. The following is a detailed description in conjunction with the gear adjustment device and the bicycle transmission.

[0056] like Fig.10 , Fig.11 , Fig.12 As shown, the gear adjustment device includes the above-mentioned flexible driving shaft and also includes a sleeve 9. The core shaft 1 is axially installed inside the sleeve 9 and is rotatably connected to the sleeve 9; the sleeve 9 is provided with mounting grooves 10 corresponding to the number and position of the gear driving blocks 3, and the mounting groove 10 is provided with a pawl 11 that cooperates with the slot 7. The middle part of the pawl 11 is rotatably set in the mounting groove 10, and an elastic member 12 is connected between the bottom of one end of the pawl 11 and the mounting groove 10, which is used to bounce up the end and extend the bottom of the other end of the pawl 11 into the rotation path of the slot 7.

[0057] like Fig.10 , Fig.13As shown, a plurality of shift gears 30 are sleeved on the outer side of the shaft sleeve 9. The shift gears 30 can rotate on the shaft sleeve 9. The shift gears 30 are limited on the shaft sleeve 9 by gaskets 6 and correspond to the positions of the pawls 11 one by one. On the one hand, the gaskets 6 are used to separate and limit the left and right movements of each shift gear 30, and at the same time are used to limit the position of the pawls 11. There is a rotating block on each side of the pawl 11 in this scheme. The gaskets 6 on both sides rotate the rotating blocks on both sides of the pawl 11 in the mounting groove 10 so that it can rotate in the mounting groove 10. An elastic member 12, such as a spring, is installed under one end of the pawl 11, so that when one end of the pawl 11 enters the arc-shaped recessed portion of the gear driving block 3, the other end of the pawl 11 can be tilted; when one end of the pawl 11 slides out of the arc-shaped recessed portion of the gear driving block 3, the other end of the pawl 11 compresses the spring and falls. The inner circumference of the shift gear 30 is provided with internal teeth. When the core shaft 1 is rotated, a ratchet 11 on the core shaft 1 bounces up at one end under the action of the elastic member 12, thereby clamping the internal teeth of the shift gear 30 corresponding to the ratchet 11.

[0058] like Fig.13 , Fig.14 , Fig.15 As shown, the bicycle transmission includes an input shaft 31, one end of the input shaft 31 is rotatably provided with an output gear shaft 32, and the output gear shaft 32 is keyed to an output gear 33; an end of the input shaft 31 away from the output end is keyed to an input gear 34, and the output gear shaft 32 is keyed to an output gear 33; the input gear 34 and the output gear 33 are respectively meshed with the shift gear 30; a planetary gear set for shifting is installed at the end of the flexible driving spindle.

[0059] When shifting is required, the shifting device drives the planetary gear set, and the planetary gear set drives the core shaft 1 to rotate a certain angle. In this process, as the core shaft 1 rotates, the end of the pawl 11 away from the elastic member 12 slides on the arc-shaped outer surface of the gear driving block 3. When sliding into the slot, the end of the pawl 11 with the elastic member 12 can bounce up, and the end of the pawl 11 that bounces up and protrudes can clamp the inner clamping teeth of the corresponding gear 30 that is rotatably mounted on the outer side of the sleeve 9. According to the gear configuration, two gears 30 are clamped and transmitted with the corresponding pawls 11 each time the gear is shifted, and the two gears 30 are respectively meshed with the input gear 34 and the output gear 33 to achieve gear engagement.

[0060] The input shaft 31 is connected to the bicycle pedal, and the output shaft is connected to the chainring 35. When the bicycle is pedaling, the input shaft 31 drives the input gear 34 to rotate under the drive of the pedal, and the input gear 34 drives the shift gear 30 to rotate, wherein the shift gear 30 not stuck with the ratchet 11 is idle, and the shift gear 30 stuck with the ratchet 11 will drive the shaft sleeve 9 to rotate, and the shaft sleeve 9 drives another shift gear 30 stuck with the ratchet 11 to rotate and output power to the output shaft through the output gear 33, and the output shaft transmits the power to the chainring 35, and the chainring 35 transmits the power to the rear wheel through the chain. According to the cooperation of the input gear 34, the output gear 33, and the shift gear 30, different transmission ratios can be achieved.

[0061] Under load conditions, such as riding on flat roads and gentle slopes, the pedal force is in a light load state, and gears can generally be directly increased or decreased. For example, when climbing a slope, a large force is required to drive the pedals, which is a heavy load state, and the pedaling frequency needs to be reduced to increase or decrease gears. The bicycle transmission in the prior art, such as the patent number 202210071876.X, is a speed change device, Figure 8 The shifting mandrel 1 shown in the patent has an integrated structure of the cam and the shifting mandrel 1. When a gear needs to be increased under load, for example, when switching from the fifth gear to the sixth gear, due to the load state, one end of the ratchet 11 corresponding to the fifth gear is stuck with the corresponding arc-shaped recessed portion of the cam, and the other end of the ratchet 11 corresponding to the fifth gear is squeezed under the action of the elastic member 12 and still tilted, and the tilted end cannot be disengaged from the shift gear 30 corresponding to the fifth gear. At this time, since the cam and the mandrel 1 in the patent are an integrated structure, the mandrel 1 cannot rotate, resulting in one end of the ratchet 11 corresponding to the sixth gear cannot slide on the corresponding cam and cannot enter the arc-shaped recessed portion of the cam, and the other end of the ratchet 11 corresponding to the sixth gear cannot tilt, so that the ratchet 11 corresponding to the sixth gear cannot be stuck with the corresponding shift gear 30, and the sixth gear cannot be engaged. Therefore, this type of spindle 1 structure needs to stop when shifting up. Only when the pedal is stopped and no large force is generated between the ratchet 11 corresponding to the fifth gear and the arc-shaped recessed portion of the cam, can the load state be ended, thereby driving the shifting spindle 1 to rotate, so that one end of the ratchet 11 corresponding to the fifth gear slides on its corresponding arc-shaped recessed portion into the side of the cam, so that the other end of the ratchet 11 corresponding to the fifth gear squeezes the elastic member 12 and falls, and then disengages from the corresponding shift gear 30; at the same time, one end of the ratchet 11 corresponding to the sixth gear slides into the corresponding arc-shaped recessed portion of the cam, so that the other end of the ratchet 11 corresponding to the sixth gear is stuck with the corresponding speed gear, and the sixth gear can be engaged. The same is true for downshifting.

[0062] In this scheme, a six-speed transmission is taken as an example. The angle difference between adjacent gear drive blocks 3 and positioning bosses 2 along the circumference of the core shaft 1 is 60°. Under load, although one end of the ratchet 11 corresponding to the fifth gear is stuck in the arc-shaped recessed portion of the gear drive block 3 corresponding to the fifth gear, the positioning boss 2 and the gear drive block 3 are separate structures, and the gear drive block 3 is provided with a clearance notch 4 that matches the positioning boss 2 on the edge of its own center hole, which is used to provide a swingable gap for the positioning boss 2. The core shaft 1 is rotatable, and the shifting device can first drive the core shaft 1 to rotate through the planetary gear set and drive the positioning boss 2 to rotate at an angle corresponding to the clearance notch 4, such as 60°. Since the torsion spring 8 connects the core shaft 1 and the gear drive block 3 corresponding to the sixth gear, the gear drive block 3 also rotates 60°, so that one end of the ratchet 11 corresponding to the sixth gear slides into the arc-shaped recessed portion of the gear drive block 3 corresponding to the sixth gear, and the other end of the ratchet 11 corresponding to the sixth gear is tilted, thereby clamping the shift gear 30 corresponding to the sixth gear, and entering the sixth gear state. At the same time, since the torsion spring 8 is connected to the mandrel 1 and the gear drive block 3, the mandrel 1 rotates, and the torsion spring 8 connected to the gear drive block 3 corresponding to the fifth gear generates torque, and the gear drive block 3 corresponding to the fifth gear rotates by half the central angle of the notch 4, and the ratchet 11 corresponding to the fifth gear is located at the edge of the arc-shaped recessed portion of the gear drive block 3 corresponding to the fifth gear and has not yet been disengaged. At the moment when the sixth gear is completed, since the sixth gear teeth are larger than the fifth gear, the speed of the shift gear 30 corresponding to the sixth gear is faster than the speed of the shift gear 30 corresponding to the fifth gear, and under the stress of the torsion spring 8, the shift gear 30 corresponding to the fifth gear can press one end of its corresponding ratchet 11 out of the arc-shaped recessed portion of the gear drive block 3 corresponding to the fifth gear, and slide on the outer edge of the gear drive block 3. At the same time, due to the action of the torsion spring 8, the gear drive block 3 corresponding to the fifth gear is automatically reset, so that the previous gear is automatically reset after the next gear is completed, and the effect of first gear and backward gear is achieved. The foot does not need to stop during the process of shifting, and load shifting is achieved during riding, which greatly improves the riding experience.

[0063] Downshifting in case of light load or heavy load:

[0064] For example, when the second gear is reduced by one gear, the gear-adjusting device drives the flexible driving mandrel to rotate in the opposite direction through the planetary gear set. At this time, the positioning boss 2 abuts against the edge of the notch on the gear drive block 3, and the positioning boss 2 on the flexible driving mandrel rotates, thereby driving the gear drive block 3 to rotate. At this time, one end of the ratchet 11 corresponding to the first gear slides into the arc groove in the corresponding gear drive block 3 to achieve gear engagement. At the same time, since the speed ratio of the second gear is higher than that of the first gear, under light load conditions, such as flat roads, gentle slopes, and downhills, since the force on the arc recess of the ratchet 11 corresponding to the second gear and the corresponding gear drive block 3 is very light, the corner of one end of the arc groove of the gear drive block 3 corresponding to the second gear can be driven by the positioning boss 2, and the lever principle can be used to lift off one end of the ratchet 3 corresponding to the second gear, so that the end is separated from the arc groove of the corresponding gear drive block 3 and enters the outer surface of the gear drive block 3, so that the other end of the ratchet 3 corresponding to the second gear compresses the elastic member to complete the gear reduction process. The same is true for the heavy-load downshifting process, but at this time, since the force on the arc-shaped depression of the pawl 11 corresponding to the second gear and the gear driving block 3 corresponding to the second gear is very large, it is only necessary to reduce the pedaling frequency and reduce the force to continue to complete the above-mentioned downshifting steps. The present invention solves the problem that the foot needs to be stopped for upshifting and downshifting in several types of internal transmissions in the prior art, or the foot needs to be stopped for upshifting but must be stopped for downshifting, or the foot needs to be stopped and the foot needs to be stepped on in the opposite direction at a certain angle (reverse foot) during the downshifting process.

[0065] The gear shifting process of the utility model can be completed instantly. On the basis of the above-mentioned gear shifting process, the user can realize any gear shifting by continuously operating the gear shifting device, such as directly from 5th gear, 4th gear, 3rd gear, 2nd gear to 1st gear. There is no need to shift from a high gear to a low gear like the external transmission in the prior art, and it is also necessary to slide for a certain distance before the gear can be shifted to the 1st gear. This solves the pain point of the external transmission and can meet the rider's requirement to obtain the desired riding speed according to the current road conditions.

[0066] Preferably, the number of the positioning boss 2, the gear drive block 3, and the pawl 11 are all more than two, so as to meet the requirements of multi-gear switching. The adjacent pawls 11 are arranged 180 degrees opposite to each other in order to avoid opening a mounting hole for installing the pawl 11 on one side of the sleeve 9. If the mounting hole is a through hole, it will make the installation of the pawl 11 inconvenient. If the holes are separated, the corresponding sleeve 9 will be larger in size to fit. In this solution, the pawls are arranged 180 degrees opposite to each other, which is convenient for opening holes on the corresponding sides of the sleeve 9, facilitating the installation of the pawl 11, and at the same time does not affect the function of the original pawl 11.

[0067] Compared with the prior art, the present solution does not require a shift fork to switch between different gears and engage with the ratchet 11, and the gear switching is smooth and the volume is smaller.

[0068] Better, such as Figure 4 , Figure 5 , Figure 7 , Figure 8 As shown, a gear-increasing device 13 which can slide axially along the core shaft 1 is mounted on one end of the core shaft 1; a gear-increasing device 13 is provided with a gear driving part 14, and when the core shaft 1 is rotated to an angle matching with the gear-increasing device 13, the gear-increasing device 13 can move linearly along the axial direction of the core shaft 1; a ratchet 11 matching with the gear driving part 14 is provided on the sleeve 9 at a position corresponding to the gear driving part 14.

[0069] The gear increasing device 13 is used to double the number of gears within the limited volume of the shaft sleeve 9, providing a smoother gear shifting experience. The gear driving unit 14 has the same function as the gear driving block 3, and is used to make the other end of the pawl 11 tilt up and clamp the corresponding gear 30 when one end of the corresponding pawl 11 slides into the arc-shaped recessed portion on the gear driving unit 14.

[0070] Preferably, a slide groove 15 is provided on the side wall of one end of the core shaft 1 in the axial direction, and the gear-increasing device 13 is sleeved on the core shaft 1 at a position corresponding to the slide groove 15; a limit rod 16 is installed on the outer side of the gear driving part 14, and the limit rod 16 extends into the slide groove 15; the side wall of the gear-increasing device 13 from the inner end to the outer end is provided with a gear driving part 14, a gear-increasing ring groove 17 and a rotating groove 18 in sequence, and a driving groove is provided on the side of the gear driving part 14, which has the same function as the arc-shaped depression on the gear driving block The rotating groove 18 includes two or more arc grooves 20 extending circumferentially along the outer side of the gear-increasing sleeve, and the tail of the arc groove 20 is connected to the starting point of the adjacent arc groove 20 through the inclined groove 21; a sliding rod 22 is vertically provided on the sleeve 9, and the sliding rod 22 extends into the rotating groove 18; when the core shaft 1 is rotated to an angle matching with the gear-increasing device 13, the rotating groove 18 can make the gear-increasing device 13 move along the slide groove 15 under the joint action of the limit rod 16 and the sliding rod 22.

[0071] Preferably, the center angle of the arc groove 20 is 360°(n-1) / n, where n is the number of gears. When the sliding rod 22 slides into the adjacent arc groove 20 through the inclined groove 21, the moving distance of the shift-increasing sleeve is equal to the center distance between the two corresponding arc grooves 20. N is the number of input gears, 360° / N. For example, the speed adjustment device has 6 gears, and the center angle of the arc groove 20 is 300°. During the first 300° of the rotation of the mandrel 1, the shift-increasing sleeve remains in place because the arc groove 20 is distributed along the circumference of the mandrel 1. During the last 60° of the rotation, the sliding rod 22 rotates to the inclined groove 21 and slides from the inclined groove 21 to the adjacent arc groove 20. The shift-increasing device 13 starts to slide along the slide groove 15 of the mandrel 1. The sliding distance of each movement of the shift-increasing sleeve is equal to the center distance between the two corresponding arc grooves 20. For example, the speed adjustment device has 4 gears, the central angle of the arc groove 20 is 270°, the first 270 degrees of the rotation of the core shaft 1 is stationary, the gear-increasing sleeve remains in place, and the sliding rod 22 rotates to the inclined groove 21 and slides from the inclined groove 21 to the adjacent arc groove 20 during the last 90° of the rotation process.

[0072] Through the setting of the gear increasing device 13, the number of gears of the gear shifting adjustment device is A*B, where A is the number of input gears 34, and B is equal to the number of circular arc grooves 20 and the number of output gears 33, so as to achieve the effect of gear doubling. Generally, three circular arc grooves 20 are provided. The more gears there are, the smoother the gear shifting is, and the more comfortable it is. At the same time, the volume is smaller, and the shift fork is omitted.

[0073] Preferably, a first planetary gear set 23 and a second planetary gear set 24 are installed at one end of the core shaft 1; the first planetary gear and the second planetary gear share a planetary bracket 2303; the sun gear 1 2301 in the first planetary gear set 23 is connected as a whole with the shaft sleeve 9, and the sun gear 1 2301 is rotatably connected to the core shaft 1; the ring gear 1 2304 in the first planetary gear set 23 is rotatably connected to the shaft sleeve 9; the sun gear 2401 in the second planetary gear set 24 is keyed to the core shaft 1, and the ring gear 2403 in the second planetary gear set 24 is sleeved on the outside of the ring gear 1 2304 in the first planetary gear set 23; the ring gear 2403 is transmission-connected with a gear shifting device, a gear shifting button 25 is fixed at the other end of the core shaft 1, and a gear position mark 26 is provided at the end of the shaft sleeve 9 corresponding to the gear shifting button 25.

[0074] The sun gear 1 2301 in the first planetary gear set 23 and the shaft sleeve 9 are both provided with mounting holes at corresponding positions, and the two are connected as a whole by connecting screws.

[0075] The outer ring gear 2403 is used to drive the rotating mandrel to shift gears, and the ring gear 1 2304 is fixed. When shifting gears, the ring gear 2403 is pulled by a pull rope or driven by a motor. Since two planetary gear sets share one planetary bracket 2303, when the ring gear 2403 is driven, since the sun gear 1 2301 is rotatably connected to the mandrel 1 and fixedly connected to the sleeve 9; the planetary bracket 2303 is stationary, it can only drive the planetary gear 2 2402 to drive the sun gear 1 2401, and rotate a certain angle to achieve gear shifting.

[0076] In this embodiment, an indicating arrow is installed or printed on the shift knob 25, and the gear position mark 26 is the gear position corresponding to the end of the sleeve 9; Fig.16 , Fig.17 As shown, one or more positioning grooves 27 are provided inside the sleeve 9 at one end close to the planetary bracket 2303, and an elastic clamp 28 matching the positioning groove 27 is provided on the core shaft 1. The elastic clamp 28 can enter or leave the positioning groove 27 when the core shaft 1 rotates. The positioning groove 27 is used to initially locate the gear position of the speed adjustment device. There is at least one elastic clamp 28, and preferably two or more.

[0077] Preferably, a rope groove 2404 is provided on the outer side of the second ring gear 2403 in the second planetary gear set 24, and the gear shifting device is a gear shifting rope 38 wound around the rope groove 2404. The more turns of the rope groove 2404, the longer the gear shifting rope 38 can be wound. The rope groove 2404 in this solution has more than 2 turns, which is suitable for a transmission with more than 10 gears.

[0078] After the gear position of the speed adjustment device is initially positioned, when the pull rope 38 for switching gears is used for a long time, the pull rope 38 will become elongated, which will cause inaccurate gear switching. This solution can quickly restore to the gear position corresponding to the length of the pull rope 38 by rotating the core shaft 1 through the gear adjustment knob 25 and pointing through the arrow on the gear mark 26.

[0079] Preferably, the gear shifting device is a control motor, which is in transmission connection with the second gear ring 2403 to drive the second gear ring 2403 to rotate. The control motor can be a stepper motor, which is used to drive the second gear ring 2403 to rotate in the forward and reverse directions, thereby performing gear shifting.

Claims

1. A flexible drive spindle, characterized in that: The invention comprises a core shaft (1) and a plurality of positioning bosses (2) arranged axially on the outer wall of the core shaft (1); a gear drive block (3) corresponding in position and number to the positioning bosses (2) is mounted on the core shaft (1); adjacent gear drive blocks (3) and adjacent positioning bosses (2) are evenly distributed along the circumference of the core shaft (1); the gear drive block (3) is provided with a clearance notch (4) matched with the positioning boss (2) at the edge of its own center hole, so as to provide a swingable gap for the positioning boss (2); the outer edge of the gear drive block (3) is arc-shaped, and a clamping groove (7) is provided on the outer edge; and a torsion spring (8) is also included, one end of the torsion spring (8) is fixed on the core shaft (1), and the other end is clamped on the gear drive block (3).

2. The flexible drive mandrel according to claim 1, characterized in that: The angle between adjacent positioning bosses (2) along the circumference of the core shaft (1) is 40-90 degrees.

3. The flexible drive mandrel according to claim 1 or 2, characterized in that: The clearance gap (4) is fan-shaped, and the central angle of the fan-shaped circle is 360° / N, wherein N is the number of gear positions; or, when N is 6 or less than 5, the central angle of the fan-shaped circle is 60°, 72° or 52°.

4. A gear adjustment device, characterized in that: It comprises the flexible drive spindle as described in any one of claims 1 to 3, and also comprises a sleeve (9), the spindle (1) is axially mounted inside the sleeve (9) and is rotatably connected to the sleeve (9); the sleeve (9) is provided with mounting grooves (10) corresponding to the number and position of the gear drive blocks (3), a pawl (11) matching the slot (7) is provided in the mounting groove (10), the middle part of the pawl (11) is rotatably arranged in the mounting groove (10), an elastic member (12) is connected between the bottom of one end of the pawl (11) and the mounting groove (10), which is used to bounce up the end and extend the bottom of the other end of the pawl (11) into the rotation path of the slot (7).

5. The gear adjustment device according to claim 4, characterized in that: The ratchet (11) is cross-shaped, a gasket (6) is sleeved on the shaft sleeve (9), and both sides of the ratchet (11) are rotatably mounted in the mounting groove (10) through the gasket (6).

6. The gear adjustment device according to claim 4 or 5, characterized in that: The number of the ratchet claws (11) is more than two, and adjacent ratchet claws (11) are arranged opposite to each other at 180 degrees.

7. The gear adjustment device according to claim 4 or 5, characterized in that: A gear-increasing device (13) is sleeved on one end of the core shaft (1) and can slide axially along the core shaft (1); a gear-increasing device (13) is provided with a gear driving part (14); when the core shaft (1) rotates to an angle that matches the gear-increasing device (13), the gear-increasing device (13) can move linearly along the axial direction of the core shaft (1); and a ratchet (11) that matches the gear driving part (14) is provided on the shaft sleeve (9) at a position corresponding to the gear driving part (14).

8. The gear adjustment device according to claim 6, characterized in that: A slide groove (15) is provided on the side wall of one end of the core shaft (1) along the axial direction, and the gear-increasing device (13) is sleeved on the core shaft (1) at a position corresponding to the slide groove (15); a limit rod (16) is installed on the outer side of the gear driving part (14), and the limit rod (16) extends into the slide groove (15); the side wall of the gear-increasing device (13) from the inner end to the outer end is provided with a gear driving part (14), a gear-increasing ring groove (17) and a rotation groove (18) in sequence, and a driving groove (19) is provided on the side surface of the gear driving part (14); the rotation groove (18) The invention comprises two or more circular arc grooves (20) extending in the circumferential direction of the outer side of the gear-increasing sleeve, wherein the tail of the circular arc groove (20) is connected to the starting point of the adjacent circular arc groove (20) through an inclined groove (21); a sliding rod (22) is vertically arranged on the shaft sleeve (9), and the sliding rod (22) extends into the rotating groove (18); when the core shaft (1) rotates to an angle matching with the gear-increasing device (13), the rotating groove (18) can make the gear-increasing device (13) move along the sliding groove (15) under the joint action of the limiting rod (16) and the sliding rod (22).

9. The gear adjustment device according to claim 8, characterized in that: The central angle of the circular arc groove (20) is 360°(n-1) / n, where n is the number of gear positions. When the sliding rod (22) slides into the adjacent circular arc groove (20) through the inclined groove (21), the moving distance of the gear-increasing sleeve is equal to the center distance between the two corresponding circular arc grooves (20).

10. The gear adjustment device according to claim 4, 5, 8 or 9, characterized in that: A first planetary gear set (23) and a second planetary gear set (24) are mounted on one end of the spindle (1); the first planetary gear and the second planetary gear share a planetary bracket (2303); a sun gear 1 (2301) in the first planetary gear set (23) is connected to the shaft sleeve (9) as a whole, and the sun gear 1 (2301) is rotatably connected to the spindle (1); a ring gear 1 (2304) in the first planetary gear set (23) is rotatably connected to the shaft sleeve (9); a sun gear 2 (2401) in the second planetary gear set (24) is key-connected to the spindle (1), and a ring gear 2 (2403) in the second planetary gear set (24) is sleeved on the outside of the ring gear 1 (2304) in the first planetary gear set (23); a gear shifting device is drivingly connected to the ring gear 2 (2403), a gear shifting button (25) is fixed to the other end of the spindle (1), and a gear position mark (26) is provided at the end of the shaft sleeve (9) corresponding to the gear shifting button (25).

11. The gear adjustment device according to claim 6, characterized in that: A first planetary gear set (23) and a second planetary gear set (24) are mounted on one end of the spindle (1); the first planetary gear and the second planetary gear share a planetary bracket (2303); a sun gear 1 (2301) in the first planetary gear set (23) is connected to the shaft sleeve (9) as a whole, and the sun gear 1 (2301) is rotatably connected to the spindle (1); a ring gear 1 (2304) in the first planetary gear set (23) is rotatably connected to the shaft sleeve (9); a sun gear 2 (2401) in the second planetary gear set (24) is key-connected to the spindle (1), and a ring gear 2 (2403) in the second planetary gear set (24) is sleeved on the outside of the ring gear 1 (2304) in the first planetary gear set (23); a gear shifting device is drivingly connected to the ring gear 2 (2403), a gear shifting button (25) is fixed to the other end of the spindle (1), and a gear position mark (26) is provided at the end of the shaft sleeve (9) corresponding to the gear shifting button (25).

12. The gear adjustment device according to claim 7, characterized in that: A first planetary gear set (23) and a second planetary gear set (24) are mounted on one end of the spindle (1); the first planetary gear and the second planetary gear share a planetary bracket (2303); a sun gear 1 (2301) in the first planetary gear set (23) is connected to the shaft sleeve (9) as a whole, and the sun gear 1 (2301) is rotatably connected to the spindle (1); a ring gear 1 (2304) in the first planetary gear set (23) is rotatably connected to the shaft sleeve (9); a sun gear 2 (2401) in the second planetary gear set (24) is key-connected to the spindle (1), and a ring gear 2 (2403) in the second planetary gear set (24) is sleeved on the outside of the ring gear 1 (2304) in the first planetary gear set (23); a gear shifting device is drivingly connected to the ring gear 2 (2403), a gear shifting button (25) is fixed to the other end of the spindle (1), and a gear position mark (26) is provided at the end of the shaft sleeve (9) corresponding to the gear shifting button (25).

13. The gear adjustment device according to claim 4, 5, 8, 9, 11 or 12, characterized in that: One or more positioning grooves (27) are provided on the inner side of one end of the shaft sleeve (9), and an elastic clamp (28) matching the positioning grooves (27) is correspondingly provided on the core shaft (1). The elastic clamp (28) can enter or leave the positioning grooves (27) when the core shaft (1) rotates.

14. The gear adjustment device according to claim 10, characterized in that: One or more positioning grooves (27) are provided on the inner side of one end of the shaft sleeve (9), and an elastic clamp (28) matching the positioning grooves (27) is correspondingly provided on the core shaft (1). The elastic clamp (28) can enter or leave the positioning grooves (27) when the core shaft (1) rotates.

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