A dual axle variable speed device
By employing multiple sets of clutch ratchet teeth and multiple transmission paths in the gear assembly design of the dual-shaft transmission device, the number of gears can be increased within a limited space, simplifying the structure and reducing weight and volume, thus solving the problems of complex structure and excessive size in the existing technology.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN GEESE TECH CO LTD
- Filing Date
- 2026-06-16
- Publication Date
- 2026-07-21
Smart Images
Figure CN122429210A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of transmission technology, specifically to a dual-shaft transmission device. Background Technology
[0002] A mid-drive bicycle system integrates the gear transmission mechanism into the bottom bracket and the cranks of the left and right pedals. Compared to traditional exposed chain derailleurs and rear hub derailleurs, it offers advantages such as high integration, better protection, and stronger transmission stability, making it a core gearing solution for high-end commuting, long-distance touring, and electric-assist bicycles. Currently, mainstream high-performance mid-drive systems generally employ a dual-shaft parallel transmission architecture. This architecture core includes two parallel drive shafts and a shift shaft, with two sets of parallel gears forming a two-stage gear system. Gear shifting is achieved through a shifting mechanism (shift fork + spline sleeve). The basic principle is that pedaling the input shaft rotates the shift shaft via the first-stage gear set, and then the shift shaft transmits power back to the output component mounted on the drive shaft via the second-stage gear set. Typically, to achieve 18 speeds, the first stage requires six pairs of gears, and the second stage requires three pairs, thus requiring at least nine pairs (18 gears) in total.
[0003] However, existing dual-shaft mid-mounted gearboxes have significant structural design shortcomings when setting multiple gears. To increase the number of gears, more gear sets and transmission components have to be stacked, resulting in a complex internal structure and an increased number of parts. This not only significantly increases the overall weight of the gearbox, affecting the bicycle's lightweight design, but also leads to an excessively large gearbox size, making it difficult to integrate compactly into the limited space of the frame's bottom bracket.
[0004] Therefore, how to simplify the internal structure of the gearbox, reduce its size and weight while providing multi-gear shifting is a technical problem that urgently needs to be solved in the field of mid-drive bicycle shifting systems. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide a dual-shaft speed change device.
[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: This invention provides a dual-shaft speed change device, comprising: The first shifting component comprises a first-stage clutch ratchet, a gear assembly with multiple transmission path structures, and a multi-stage main gear sleeved on the gear assembly. The first shifting component can push any one of the first-stage clutch ratchet protrusions to engage the gear assembly, thereby causing the corresponding transmission path structure to drive the multi-stage main gear to rotate. Driven shaft, multiple sets of two-stage clutch ratchet teeth, a second shifting assembly and push-pull shaft movable within the driven shaft, and a multi-stage driven gear assembly sleeved on the driven shaft, an output ratchet assembly, and an output gear set with multiple output transmission paths; Moving the second shifting component can push any set of secondary clutch ratchet protrusions to engage with the multi-stage driven gear component, and the multi-stage main gear component and the multi-stage driven gear component mesh to drive the driven shaft to rotate. When one end of the second shift assembly extends into the push-pull shaft and is located in the middle, moving the second shift assembly can squeeze the push-pull shaft to deform and expand the inner diameter, so that the second shift assembly can slide to switch the engagement position. The push-pull shaft is fixedly connected to the output ratchet, and when one end of the second shifting component is located at both ends of the push-pull shaft, moving the second shifting component can simultaneously move the push-pull shaft and the output ratchet, so that the output ratchet slides along the axial direction to transmit the corresponding output path structure.
[0007] The beneficial effects of this invention are: First, by sequentially setting multiple sets of first-stage clutch ratchet teeth rotatably connected to the first shift assembly along its axial direction, and then sleeve the gear assembly around the axis of the first shift assembly, multiple transmission path structures are arranged to correspond to multiple sets of first-stage clutch ratchet teeth. A multi-stage main gear component, simultaneously connected to the output ends of multiple transmission path structures, is sleeved on the gear assembly. This allows the first shift assembly to drive the first-stage clutch ratchet teeth to rotate around its axis, protruding outwards to engage with the gear assembly and transmitting power to the corresponding transmission path structures. Thus, the power of the first shift assembly can be output in multiple transmission ratios through the cooperation of multiple sets of first-stage clutch ratchet teeth and the gear assembly with multiple transmission path structures. Consequently, the multi-stage main gear component can achieve multiple speeds based on multiple transmission ratio outputs.
[0008] Secondly, by sequentially arranging multiple sets of rotatable secondary clutch ratchet teeth on the driven shaft, and sleeved on the driven shaft around its axis, the multi-stage driven gear consists of multiple gears of different diameters arranged sequentially. The multi-stage master gear is equipped with gears of different diameters corresponding to the multi-stage driven gear. Combined with a second shifting assembly located inside the driven shaft and movable along its axis, the movement of the second shifting assembly can push any set of secondary clutch ratchet teeth to rotate around the driven shaft axis, engaging the corresponding diameter of the multi-stage driven gear. This allows the multi-stage master gear to drive the driven shaft to rotate through the multi-stage driven gear and further engage the secondary clutch ratchet teeth. In other words, through a rotational transmission output, the multi-stage master gear can drive the driven shaft to rotate at multiple speeds with the same number of stages as the multi-stage driven gear after the structural design of the multi-stage driven gear, multiple sets of secondary clutch ratchet teeth, and the second shifting assembly.
[0009] Finally, by sleeved on the driven shaft with an output gear set and an output ratchet component having multiple output paths around the driven shaft axis, and with the output ratchet component slidingly connected to it along the driven shaft axis, and by moving and changing the installation position of the output ratchet component within the output gear set, the output ratchet component can switch to transmission connection with any output transmission path structure within the output gear set. Additionally, a push-pull shaft component is movably disposed within the driven shaft. One end of the second shifting component extends into and engages with the push-pull shaft component. When one end of the second shifting component is located at the middle position of the push-pull shaft component, the second shifting component moving along the driven shaft axis generates a push-pull force on the push-pull shaft component. This push-pull force compresses the push-pull shaft component, causing elastic deformation at its middle position to expand its inner diameter, thus causing the second shifting component to move along the driven shaft axis. However, the push-pull shaft component remains stationary; that is, one end of the second shifting component can move along the push-pull shaft component. When elastic deformation occurs, it moves axially along the driven shaft and switches to the corresponding locking position. When one end of the second shift assembly is located near or away from the end of the push-pull shaft, moving the second shift assembly can simultaneously pull or push the push-pull shaft along the driven shaft axis, and cause the output ratchet to slide synchronously with the driven shaft, realizing the switching of multiple output path structures within the output gear set. In other words, when the multi-stage main gear outputs a rotational transmission and the driven shaft rotates at a certain speed via the multi-stage driven gear, multiple sets of secondary clutch ratchet teeth, and the second shift assembly, the output gear set can drive the sprocket to rotate at the same speed as the output transmission path structure through the structural design of the second shift assembly, the push-pull shaft, and the output ratchet.
[0010] In summary, when the first shifting component drives the multi-stage main gear via the gear assembly, it can output N1 speeds. When the multi-stage main gear drives the multi-stage driven gear at a specific speed, the output can drive the driven shaft to rotate at N2 speeds after passing through the two-stage clutch ratchet. When the driven shaft rotates at a speed, it can drive the output gear set to output N3 speeds after passing through the second shifting component, push-pull shaft, and output ratchet. In other words, the dual-shaft transmission device of this solution can achieve N1 x N2 x N3 power outputs. Compared with the traditional dual-shaft transmission device, which requires adding independent gear sets to increase the number of gears, this invention can effectively simplify the internal gear transmission structure of the gearbox while increasing the multi-gear transmission function, thereby reducing the overall size and weight. Attached Figure Description
[0011] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0012] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2This is a cross-sectional schematic diagram of the overall structure of the present invention; Figure 3 This is a schematic diagram of the structure of the multi-stage main gear, the multi-stage driven gear, and the output gear set in this invention; Figure 4 This is a schematic diagram of the first transmission path structure of the gear assembly in an embodiment of the present invention; Figure 5 This is a schematic diagram of the second transmission path structure of the gear assembly in an embodiment of the present invention; Figure 6 This is a schematic diagram of the third transmission path structure of the gear assembly in an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of the multi-stage master gear and the multi-stage slave gear in this invention; Figure 8 This is a schematic diagram of the structure of the first main gear, ratchet disk structure, and first planetary disk in an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of the multi-stage driven gear, the output ratchet, and the output gear set in this invention; Figure 10 This is a schematic cross-sectional view of the multi-stage driven gear, output ratchet, and output gear set in this invention. Figure 11 This is a cross-sectional structural diagram of the second shifting component, push-pull shaft, output ratchet component, and output gear set in this invention. Figure 12 This is a schematic diagram of the structure of the second shifting assembly, the push-pull shaft, and the output ratchet assembly in this invention; Figure 13 This is an exploded view of the second shifting assembly, push-pull shaft, and output ratchet assembly in this invention; Figure 14 For the present invention Figure 11 Enlarged view of part A in the middle.
[0013] The attached diagram lists the components represented by each number as follows: 10. Housing; 20. Hydraulic drive device; 30. Gear sprocket; 1. First shift assembly; 11. First-stage clutch ratchet; 12. Drive shaft; 121. Rotating hole; 13. Shift shaft; 131. Protrusion; 2. Gear assembly; 21. First planetary gear set; 211. First sun gear; 212. First planetary gear; 213. First internal gear ring; 214. Ratchet disk structure; 2141. First ratchet; 215. First planetary disk; 22. Ratchet transmission component; 221. Second ratchet; 23. Second planetary gear set; 231. Second sun gear; 232. Second planetary gear; 233. Second internal gear ring; 234. Third ratchet; 3. Multi-stage main gear component; 31. Main gear seat; 32. First 33. Main gear; 34. Second main gear; 4. Third main gear; 5. Driven shaft; 6. Secondary clutch ratchet; 7. Sliding hole; 8. Second shift assembly; 9. Shift push-pull shaft; 10. Drive cylinder; 11. Telescopic shaft; 12. Locking protrusion; 13. Shift boss; 14. Push-pull shaft assembly; 15. Push-pull shaft body; 16. Telescopic through hole; 17. Locking groove; 18. Splicing shaft body; 19. Locking ring groove; 10. Elastic hoop; 11. Connecting shaft; 12. Multi-stage driven gear assembly; 13. First driven gear; 14. Second driven gear; 15. Third driven gear; 16. Output ratchet assembly; 17. Output gear set; 18. First output wheel; 19. Second output wheel. Detailed Implementation
[0014] The following will clearly and completely describe the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention. Furthermore, all connections / linkages involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. The various technical features in this invention can be combined interactively without contradicting each other.
[0015] The core of this invention lies in the fact that by using movable shafts inside the drive shaft 12 and driven shaft 4, along with multiple sets of clutch ratchet teeth and multiple transmission paths, the number of gears can be significantly increased within a limited space, while the structure is significantly simplified and the weight and volume are reduced.
[0016] refer to Figures 1 to 13The present invention provides a dual-shaft transmission device, including a first shifting component 1, multiple sets of first-stage clutch ratchet 11, a gear assembly 2 with multiple transmission path structures, and a multi-stage main gear 3 sleeved on the gear assembly 2. The first shifting component 1 can push any set of first-stage clutch ratchet 11 to engage with the gear assembly 2, so that the corresponding transmission path structure drives the multi-stage main gear 3 to rotate. Driven shaft 4, multiple sets of two-stage clutch ratchet 41, second shift assembly 5 movable within driven shaft 4 and push-pull shaft 6, multi-stage driven gear 7 sleeved on driven shaft 4, output ratchet 8 and output gear set 9 with multiple output transmission paths. Moving the second shift component 5 can push any set of secondary clutch ratchet 41 protrusions to engage the multi-stage driven gear 7, and the multi-stage main gear 3 meshes with the multi-stage driven gear 7 to drive the driven shaft 4 to rotate. When one end of the second shift assembly 5 extends into the push-pull shaft 6 and is located in the middle, moving the second shift assembly 5 can squeeze the push-pull shaft 6 to deform and expand the inner diameter, so that the second shift assembly 5 can slide to switch the engagement position. The push-pull shaft 6 is fixedly connected to the output ratchet 8. When one end of the second shifting component 5 is located at both ends of the push-pull shaft 6, moving the second shifting component 5 can simultaneously move the push-pull shaft 6 and the output ratchet 8, so that the output ratchet 8 slides along the axial direction to transmit the corresponding output path structure.
[0017] In this embodiment, reference Figure 1-3 The dual-shaft transmission device also includes a housing 10 and two sets of hydraulic drive devices 20 disposed on the outer surface of the housing 10. The two sets of hydraulic drive devices 20 provide driving force for the transmission slide shaft 13 and the second shift assembly 5.
[0018] Specifically, the first shifting assembly 1 includes a power shaft 12 that is rotatably mounted transversely through the housing 10, and three sets of primary clutch ratchet teeth 11 arranged sequentially along the axial direction of the power shaft 12. The power shaft 12 is rotatably mounted transversely within the housing 10, with both ends extending out of the housing 10 to connect to the foot pedal crank. The user inputs power through the foot pedal to cause the power shaft 12 to rotate relative to the housing 10. The power shaft 12 is hollow internally, and contains a shifting slide shaft 13 whose axial movement can be controlled by a hydraulic drive device 20.
[0019] The drive shaft 12 has three sets of rotating holes 121 adapted to the primary clutch ratchet 11. The primary clutch ratchet 11 is rotatably disposed within the rotating holes 121. Optionally, multiple rotating holes 121 are provided in the radial direction of the drive shaft 12, and a primary clutch ratchet 11 is assembled in each hole via a spring plate. The clutch ratchet can be a pawl structure. In the free state, the spring plate causes the pawl to retract into the hole.
[0020] The transmission slide shaft 13 is provided with a protrusion 131. By driving the transmission slide shaft 13, the protrusion 131 is moved to the position of the first-stage clutch ratchet 11. With the structural setting that the cross section of the protrusion 131 is adapted to the cross section of the hollow space in the power shaft 12, the protrusion 131 can push the first-stage clutch ratchet 11 to protrude outward and engage the transmission path structure at the corresponding position in the gear assembly 2.
[0021] The gear assembly 2 is coaxially mounted on the first shift assembly 1 and includes multiple independent transmission path structures. A fixed assembly, including multiple gears of different diameters, is coaxially fixed around the gear assembly 2. Optionally, the gear assembly 2 includes a first planetary gear set 21, a ratchet transmission component 22, and a second planetary gear set 23. The power output ends of these three paths are all connected to the multi-stage main gear component 3.
[0022] It needs to be explained that when it is necessary to switch the transmission ratio at the input end, the hydraulic drive device 20 pushes the transmission slide shaft 13 inside the first shift assembly 1 to move axially. The protrusion 131 on the transmission slide shaft 13 will move to the position of a certain set of first-level clutch ratchet 11 and push the clutch ratchet to protrude radially outward, so that it changes from a retracted state to an extended state, thereby engaging with a corresponding transmission path structure in the gear assembly 2.
[0023] At this time, when the user presses the first shift component 1, power is transmitted to the multi-stage main gear component 3 through the selected transmission path, driving it to rotate. Due to the deceleration / speed-increasing effect of the first planetary gear set, the multi-stage main gear component 3 obtains the first speed. Similarly, by moving the shift slide shaft 13, the corresponding first-stage clutch ratchet 11 can be engaged with the ratchet transmission component 22 or the second planetary gear set 23, thereby obtaining the second and third speeds.
[0024] Through the structural design of the first shift assembly 1, the first-stage clutch ratchet 11, the gear assembly 2, and the multi-stage main gear 3, multiple compact planetary gear sets and ratchet mechanisms can be integrated on the same first shift assembly 1 as independent transmission paths. Switching is achieved using internally moving shafts and radially elastic pawls, avoiding the need to stack bulky external gear sets or complex shift fork structures to increase input gears, effectively reducing the axial dimension and overall volume of the device.
[0025] Specifically, the driven shaft 4 is also rotatably mounted inside the housing 10, and its axis is parallel to the axis of the first shifting assembly 1. The multi-stage main gear 3 meshes with the multi-stage driven gear 7 sleeved on the driven shaft 4. The multi-stage driven gear 7 consists of multiple gears of different diameters rotatably and sequentially sleeved on the driven shaft 4. Optionally, the multi-stage driven gear 7 is provided with a first driven gear 71, a second driven gear 72, and a third driven gear 73 of different diameters.
[0026] The secondary clutch ratchet 41 is sequentially arranged on the driven shaft 4 along the axial direction, and the connection structure between the two is the same as the connection structure between the primary clutch ratchet 11 and the drive shaft 12. A rotating hole 121 is provided at the corresponding position of the driven shaft 4, and the secondary clutch ratchet 41 is installed through a spring plate. The secondary clutch ratchet 41 can be selected as a pawl structure. In the free state, the spring plate also causes the pawl to retract into the hole.
[0027] The driven shaft 4 is hollow inside, and a second shifting assembly 5 that can be axially moved by a hydraulic drive device 20 is provided inside it. The driven shaft 4 is also provided with a push-pull shaft 6, which is sleeved on or connected to the second shifting assembly 5 and can move axially.
[0028] It needs to be explained that the multi-stage main gear 3 rotates at a specific speed, causing all the multi-stage driven gears 7 meshing with it to idle. At this time, the hydraulic drive device 20 can push the second shift assembly 5 to move axially, causing the shifting protrusion structure on it to move to the position corresponding to a certain set of secondary clutch ratchet teeth 41, pushing the ratchet pawl to protrude radially and engage with the inner ring ratchet structure of the corresponding driven gear. This causes the first driven gear 71 to rotate and transmit the rotation through the protruding secondary clutch ratchet teeth 41 to the driven shaft 4, causing the driven shaft 4 to rotate at the first speed. Similarly, by moving the second shift assembly 5, the secondary clutch ratchet teeth 41 can be engaged with the second or third driven gear 73 respectively, thereby allowing the driven shaft 4 to obtain three different speeds.
[0029] Through the structural arrangement of the driven shaft 4, the secondary clutch ratchet 41, the multi-stage driven gear 7, the second shift assembly 5, and the multi-stage main gear 3, the second shift assembly 5 inside the driven shaft 4 can selectively lock one of the three idler gears of different diameters to the driven shaft 4 simply by axial movement. This selection method, where the internal shaft drives the external ratchet, is extremely compact compared to the traditional method that requires multiple shift forks or moving the entire gear set externally. It greatly reduces the number of parts and axial space occupied, thereby significantly reducing the overall weight and size of the transmission.
[0030] Specifically, the power output end of the driven shaft 4 is equipped with an output gear set 9 and an output ratchet 8. The output gear set 9 includes multiple output transmission path structures with different transmission ratios. Optionally, the output gear set 9 includes a first output wheel 91 and a second output wheel with different diameters. By employing a gear structure design with different numbers of teeth, the first output wheel 91 and the second output wheel form two output transmission paths with different transmission ratios. The output ratchet 8 can be slidably connected to the driven shaft 4 axially and connects with the multiple output transmission path structures with different transmission ratios in the output gear set 9. Optionally, through a structure design that allows the output ratchet 8 and the push-pull shaft 6 to move synchronously, combined with a radial locking structure design between the output ratchet 8 and the driven shaft 4, the output ratchet 8 can engage with the first output wheel 91 or the second output wheel after sliding, and can drive the output wheel to rotate around the driven shaft 4.
[0031] Both the second shift assembly 5 and the push-pull shaft 6 are slidably mounted inside the driven shaft 4. The structure of the push-pull shaft 6 is designed such that its middle section can undergo radial deformation to expand its inner diameter when subjected to axial compression, while its two end sections will not.
[0032] One end of the second shift assembly 5 extends into the push-pull shaft 6. When one end of the second shift assembly 5 is located in the middle of the push-pull shaft 6, moving the second shift assembly 5 will cause the middle of the push-pull shaft 6 to deform, thereby allowing the second shift assembly 5 to slide inside the push-pull shaft 6 and switch to a new engagement position. At this time, the push-pull shaft 6 and the output ratchet 8 remain stationary. After the second shift assembly 5 moves, the shifting protrusion structure on it moves to push the secondary clutch ratchet 41 corresponding to the new engagement position. When one end of the second shift assembly 5 moves to the end of the push-pull shaft 6, continuing to move the second shift assembly 5 will directly push or pull the push-pull shaft 6, thereby causing the output ratchet 8 to slide axially along the driven shaft 4.
[0033] It should be explained that when the driven shaft 4 rotates at a specific speed, the output ratchet 8 also rotates due to its radial engagement with the driven shaft 4. Optionally, through the cooperation of the second shift assembly 5 and the push-pull shaft 6, the output ratchet 8 can be moved axially to mesh with either the first output wheel 91 or the second output wheel in the output gear set 9. Combined with the structural design of two output wheels with different diameters, the same rotational speed of the driven shaft 4 can drive the crankset 30 to obtain two different final output speeds.
[0034] The two independent gear shifting actions are controlled by the different relative positions (middle or end) of the second shifting component 5 and the push-pull shaft 6. Specifically, one is to switch the speed of the driven shaft 4 (pushing the secondary clutch ratchet 41), and the other is to switch the transmission ratio at the output end (pushing the output ratchet 8). This "one shaft, two uses" linkage design avoids the need to add an additional independent shifting mechanism and hydraulic drive source for the output end gear shifting, which not only simplifies the mechanical structure but also reduces the complexity of the control system, making it possible to achieve the effect of multiplying the number of gears in an extremely limited space.
[0035] In other words, this invention achieves a product-like increase in the total number of gears (N1×N2×N3) by providing N1 speeds at the power input end, N2 speeds at the intermediate driven shaft 4, and N3 speeds at the output end, and controlling this through a linkage shifting mechanism located inside the driven shaft 4. Specifically, in this embodiment, the power input end can provide 3 speeds, the intermediate driven shaft 4 can provide 3 speeds, and the output end can provide 2 speeds, resulting in a total of 19 gears (3×3×2). Furthermore, all shifting mechanisms in this invention are integrated within the shaft, using a ratchet clutch with different gear combinations, eliminating the need for complex external shift forks or additional gear sets. This completely solves the technical problems of complex structures, large size, and heavy weight caused by increasing the number of gears in existing transmission devices.
[0036] Preferred, Reference Figure 4-6 The gear assembly 2 includes a first planetary set 21, a ratchet drive component 22, and a second planetary set 23, which are sleeved on the first shift assembly 1. The first planetary set 21, the ratchet drive component 22, and the second planetary set 23 are all independent transmission path structures, and all three are connected to the multi-stage main gear component 3 for transmission.
[0037] In this embodiment, the gear assembly 2 includes a first planetary gear set 21, a ratchet transmission component 22, and a second planetary gear set 23, which are coaxially mounted on the first shift assembly 1. These three components constitute three independent transmission path structures, and the power output ends of these three paths are all connected to the multi-stage main gear component 3.
[0038] Among them, reference Figure 4-6 , Figure 7-8 The first planetary gear set 21 includes a first sun gear 211, a plurality of first planet gears 212 connected to the outer periphery of the first sun gear 211, and a first internal gear ring 213 located on the outer periphery of the first planet gears 212 and connected to them. Specifically, a ratchet disk structure 214 is integrally formed on the first internal gear ring 213. The ratchet disk structure 214 is located inside the first planetary gear set 21, and the ratchet disk structure 214 is provided with a first ratchet 2141 sleeved on the drive shaft 12.
[0039] The first planetary set 21 also includes a first planetary disk 215 that is coupled to multiple first planetary gears 212. The first planetary disk 215 is located on the outside of the first planetary set 21. The first planetary set 21 is connected to the multi-stage main gear 3 for transmission, so that the rotation of the first planetary gears 212 around the first sun gear 211 can drive the first planetary disk 215 and the multi-stage main gear 3 to rotate.
[0040] It should be explained that the inner circumference of the ratchet structure is provided with grooves for engaging with the clutch ratchet teeth. Optionally, when the corresponding first-stage clutch ratchet teeth 11 (pawl) protrudes under the push of the transmission slide shaft 13 and engages with the first ratchet 2141, the power is transmitted sequentially through the ratchet mesh structure 214, the first internal gear ring 213, the first planetary gear 212, and the first planetary carrier to the multi-stage main gear component 3, realizing the first type of speed transmission.
[0041] It should be noted that the ratchet disk structure 214 connecting the first internal gear ring 213 and the first ratchet 2141 allows the first sun gear 211 and the first ratchet 2141 to be misaligned. Simultaneously, the structure connecting the first planetary gear 212 and the multi-stage main gear 3 via the first planetary disk 215 transmits power from the first planetary gear 212 to the multi-stage main gear 3 on the outer ring. This invention, through the structural arrangement of the first planetary disk 215 and the ratchet disk structure 214, greatly improves the integration of the first planetary gear set 21 structure and reduces the space required for design.
[0042] refer to Figure 6 The ratchet drive component 22 is disc-shaped, with a hollow center forming a second ratchet 221 that is compatible with the power shaft 12. Its outer circumference is integrally fixedly connected to the multi-stage main gear component 3.
[0043] It needs to be explained that when the second set of first-stage clutch ratchet 11 protrudes and engages with the second ratchet 221, the rotation of the first shifting component 1 is directly transmitted to the multi-stage main gear component 3 through the ratchet transmission component 22, realizing direct transmission with the second speed and a transmission ratio of 1:1.
[0044] refer to Figure 4-6 The second planetary gear set 23 includes a second sun gear 231, multiple second planet gears 232 connected to the outer circumference of the second sun gear 231, and a second internal gear ring 233 located on the outer circumference of the second planet gears 232 and connected to them. Specifically, the second internal gear ring 233 is fixedly connected to the housing 10. The second planet gears 232 are connected to the disc structure of the ratchet drive 22 via a coupling, so that when the second planet gears 232 rotate around the outer circumference of the second sun gear 231, they can drive the ratchet drive 22 and the multi-stage main gear 3 to rotate. A third ratchet 234 adapted to the drive shaft 12 is formed in the hollow center of the second sun gear 231.
[0045] It needs to be explained that when the third set of first-level clutch ratchet 11 protrudes and engages with the third ratchet 234, the power is transmitted to the multi-stage main gear 3 through the second sun gear 231, the second planet gear 232, and the structure linked with the ratchet transmission component 22, thus realizing a third type of speed transmission different from the first planetary set 21.
[0046] This invention integrates three different gear ratios into a coaxial compact module and uses a ratchet as the shift interface. Compared to connecting multiple independent gearboxes in series, this "integrated planetary gear set + ratchet" design makes great use of radial space and shortens the axial length, so that the size and weight of the device can be effectively controlled while realizing multiple gears at the input end.
[0047] Preferred, Reference Figure 7 The multi-stage main gear component 3 includes a main gear seat 31 connected to the gear assembly 2, and a first main gear 32, a second main gear 33 and a third main gear 34 that are sequentially fixedly sleeved on the main gear seat 31 and have a decreasing number of teeth. The multi-stage driven gear component 7 includes a first driven gear 71, a second driven gear 72, and a third driven gear 73 that are rotatably and sequentially sleeved on the driven shaft 4 with increasing number of teeth. The first driven gear 71, the second driven gear 72, and the third driven gear 73 are respectively meshed with the first master gear 32, the second master gear 33, and the third master gear 34.
[0048] In this embodiment, the multi-stage main gear component 3 includes a main gear seat 31, and a first main gear 32, a second main gear 33 and a third main gear 34 that are sequentially fixedly sleeved on it, with the number of teeth of the three decreasing sequentially.
[0049] Specifically, the first main gear 32 is integrally formed with the outer periphery of the first planetary disk 215. The first main gear 32 is connected to the main gear seat 31 by a radial limiting structure, so that when the first planetary disk 215 drives the first main gear 32 to rotate around its axis, it can simultaneously drive the main gear seat 31 to rotate. The main gear seat 31 is located on the outer periphery of the ratchet transmission component 22, and the two are integrally formed and connected. Combined with the second main gear 33 and the third main gear 34, which are connected to the main gear seat 31 by a radial limiting structure, the main gear seat 31 can simultaneously drive the three main gears to rotate around its axis.
[0050] The multi-stage driven gear component 7 includes a first driven gear 71, a second driven gear 72, and a third driven gear 73, which are rotatably mounted on the driven shaft 4 in sequence. The number of teeth of the three gears increases sequentially, and they mesh with the first, second, and third master gears respectively.
[0051] This invention utilizes a stepped gear set design as the foundation for multi-stage transmission on the driven shaft 4. Specifically, the three gears on the multi-stage main gear assembly 3 have different diameters, ensuring that they can generate different speed ratios with the three corresponding driven gears. All gears mesh directly, eliminating the need for intermediate idler gears. When the second shifting assembly 5 inside the driven shaft 4 selects and locks any one of the driven gears, the driven shaft 4 can obtain a specific speed. This direct and compact meshing method replaces the complex gear train and synchronizer structure in traditional gearboxes, and is a key element in achieving small-volume, lightweight multi-speed transmission.
[0052] Preferred, Reference Figure 2 , Figure 9-11 The second shift assembly 5 includes a shift push-pull shaft 51, on which a shift boss 52 is provided. Moving the shift push-pull shaft 51 axially can drive the shift boss 52 to move on the driven shaft 4, and can push any set of secondary clutch ratchet teeth 41 to rotate and engage the multi-stage driven gear 7.
[0053] In this embodiment, the second shift assembly 5 is a shift push-pull shaft 51, which is provided with a shift boss 52. Optionally, the shift boss 52 is a shift protrusion. Axially moving the shift push-pull shaft 51 can drive the shift boss 52 to push any set of secondary clutch ratchet teeth 41 to protrude.
[0054] By setting a shift boss 52 on the shift push-pull shaft 51, the shift push-pull shaft 51 can be moved to drive the shift boss 52 to any set of secondary clutch ratchet 41 positions. The shift boss 52 pushes the secondary clutch ratchet 41 to rotate and protrude outwards towards the driven shaft 4 to engage with the corresponding driven gear in the multi-stage driven gear component 7, thereby realizing the engagement transmission between the driven shaft 4 and the multi-stage driven gear component 7. Since the multi-stage driven gear component 7 is composed of driven gears with different numbers of teeth, by moving the shift boss 52 to push the secondary clutch ratchet 41 corresponding to different driven gears, the driven shaft 4 can obtain different speeds and complete the gear switching.
[0055] Preferred, Reference Figure 10-11 The shift push-pull shaft 51 includes a drive cylinder 511 with one end externally connected to a drive device, and a telescopic shaft 512 with one end connected to the other end of the drive cylinder 511. The other end of the telescopic shaft 512 extends into the push-pull shaft 6 and is slidably locked in place.
[0056] In this embodiment, the shift push-pull shaft 51 includes a drive cylinder 511 and a telescopic shaft 512. One end of the drive cylinder 511 is connected to an external hydraulic drive device 20, and the other end is connected to one end of the telescopic shaft 512. The other end of the telescopic shaft 512 can extend into the push-pull shaft 6 for sliding and locking connection.
[0057] By dividing the shift push-pull shaft 51 into a drive cylinder 511 and a telescopic shaft 512, and driving the drive cylinder 511 to move within the driven shaft 4 through the drive device, and simultaneously driving the telescopic shaft 512 to move, when the other end of the telescopic shaft 512 is located in the middle section of the push-pull shaft 6, the push-pull shaft 6 can be squeezed and deformed to expand its inner diameter, so that the telescopic shaft 512 can be disengaged from its original position and slide to another position within the push-pull shaft 6 under the pulling force of the drive cylinder 511. Neither the push-pull shaft 6 nor the output ratchet 8 moves, thereby moving the second shift assembly 5 to push different groups of secondary clutch ratchet teeth 41, thereby completing the switching of the rotation speed of the driven shaft 4. When the other end of the telescopic shaft 512 is locked at both ends of the push-pull shaft 6, moving the telescopic shaft 512 toward the end of the push-pull shaft 6 can simultaneously drive the push-pull shaft 6 to move within the driven shaft 4. Combined with the connection between the output ratchet 8 and the push-pull shaft 6, it can further simultaneously drive the output ratchet 8 to slide with the driven shaft 4, thereby connecting the output ratchet 8 to the multiple output path structures within the output gear set 9, and thus outputting the rotation of the transmission shaft at multiple speeds, completing the switching of multiple transmission ratios of the output gear set 9.
[0058] Preferred, Reference Figure 11-13 The shift boss 52 is located at one end of the telescopic shaft 512. The other end of the telescopic shaft 512 can extend into the push-pull shaft 6 and be slidably locked with it. The shift boss 52 can abut against the push-pull shaft 6 to limit the depth of the telescopic shaft 512 extending into the push-pull shaft 6.
[0059] In this embodiment, the shift boss 52 is provided at one end of the telescopic shaft 512 and is used to abut against the push-pull shaft 6, thereby limiting the maximum depth to which the telescopic shaft 512 extends into the push-pull shaft 6.
[0060] By setting the shift boss 52 at one end of the telescopic shaft 512, the strength of the connection structure between the telescopic shaft 512 and the drive cylinder 511 can be increased, and the connection stability between the two can be improved. The shift boss 52 can also limit the extension depth of the telescopic shaft 512, which is slidably engaged with the push-pull shaft 6. By limiting the position distance of the shift boss 52, the second shift assembly 5 can push the secondary clutch ratchet 41 at the same time, and the push-pull shaft 6 can apply a pushing or pulling force to the output ratchet 8 to achieve the sliding of the output ratchet 8 on the driven shaft 4. Then, by moving the second shift assembly 5 and the push-pull shaft 6, the rotation speed of the shaft and the switching of multiple output transmission paths of the output gear set 9 can be completed, and the speed change can be achieved.
[0061] It should be noted that the split design with a limiting function of the shift push-pull shaft 51 is key to achieving "two independent shifting actions completed by the same shift shaft". Specifically, the drive cylinder 511 receives external power, while the telescopic shaft 512 performs the action. The positional design of the shift boss 52 ensures that when the telescopic shaft 512 reaches the end of the push-pull shaft 6, the axial force acts directly on the push-pull shaft 6, pushing it to move. This avoids the need for a separate drive mechanism for the push-pull shaft 6, greatly simplifying the internal control components of the gearbox and reducing its size.
[0062] Preferred, Reference Figure 12-13 The push-pull shaft 6 includes a push-pull shaft body 61. The push-pull shaft body 61 has a telescopic through hole 611 adapted to the telescopic shaft 512 along its axial direction. The middle section of the push-pull shaft body 61 can be radially deformed under axial force to expand the diameter of the telescopic through hole 611.
[0063] In this embodiment, the push-pull shaft component 6 includes a push-pull shaft body 61, which has an axially formed telescopic through hole 611 adapted to the telescopic shaft 512. When the middle section of the push-pull shaft body 61 is subjected to axial force, it undergoes radial deformation, thereby enlarging the diameter of the telescopic through hole 611, allowing the telescopic shaft 512 to slide out of the locking position. However, the two end sections do not deform, preventing the telescopic shaft 512 from disengaging from the locking position and maintaining a locked connection with the push-pull shaft body 61, thus enabling the push-pull shaft body 61 to move.
[0064] In one embodiment, the push-pull shaft 6 further includes a connecting shaft 62, which passes through the push-pull shaft body 61 and the driven shaft 4, with output ratchet members 8 extending from both ends of the connecting shaft 62 for locking and fixing. The driven shaft 4 has a strip-shaped sliding hole 42, the axial length of which is the distance the output ratchet member 8 slides along the driven shaft 4. Through the structural design of the sliding hole 42 combined with the connecting shaft 62, the axial movement of the push-pull shaft body 61 can drive the connecting shaft 62 and the output ratchet member 8 to move synchronously.
[0065] This invention, by forming a telescopic through hole 611 for mounting the telescopic shaft 512 in the push-pull shaft body 61, and combining the structural design that allows the middle part of the push-pull shaft body 61 to deform radially under axial compressive force to enlarge the diameter of the telescopic through hole 611, and that the two ends of the push-pull shaft body 61 do not deform under axial compressive force, allows the middle part of the moving second shift assembly 5 to deform under compressive force when one end of the telescopic shaft 512 is located in the middle section of the push-pull shaft body 61. The second shift assembly 5 moves relative to the push-pull shaft 6 to push multiple sets of secondary clutch ratchet teeth 41. When one end of the telescopic shaft 512 is located in the two ends of the push-pull shaft body 61, the end of the push-pull shaft body 61 does not deform when the second shift assembly 5 moves. The second shift assembly 5 synchronously drives the push-pull shaft 6 and the output ratchet 8 to move, completing the switching between the output ratchet 8 and different output transmission path structures.
[0066] Preferred, Reference Figure 13 The inner wall of the telescopic through hole 611 is provided with a plurality of snap-fit slots 612 spaced apart along its axial direction. The snap-fit slots 612 are formed by radial recesses along the push-pull shaft body 61. One end of the telescopic shaft 512 is radially expanded to form a snap-fit protrusion 5121, which is snap-fitted and installed in the snap-fit slots 612.
[0067] In this embodiment, a plurality of locking slots 612 are provided axially spaced on the inner wall of the telescopic through hole 611. The end of the telescopic shaft 512 is provided with a radially enlarged locking protrusion 5121, which can be locked into these locking slots 612.
[0068] This invention, through a structural design that includes multiple locking slots 612 with a radial width greater than the radial width of the telescopic through hole 611 spaced apart within the push-pull shaft body 61, and a locking protrusion 5121 with a radial width greater than the radial width of the telescopic shaft 512 formed at one end of the telescopic shaft 512 extending into the push-pull shaft body 61, ensures that when the locking protrusion 5121 is installed within the locking slots 612, the telescopic shaft 512 cannot slide within the push-pull shaft body 61. Only when the locking protrusion 5121 is installed in the locking slots 612 at the middle section of the push-pull shaft body 61 can the telescopic shaft 512 extend or retract within the push-pull shaft body 61. When radial deformation occurs due to compression, causing the telescopic through hole 611 to expand its radial width, the locking protrusion 5121 disengages from the locking groove 612 and slides along the telescopic through hole 611 to the next locking groove 612. This ensures that when the locking protrusion 5121 is set at the locking groove 612 at both ends of the push-pull shaft body 61, the push-pull shaft body 61 can move synchronously with the telescopic shaft 512 by means of the structural design of the locking protrusion 5121 and the locking groove 612, thereby driving the output ratchet 8 and the driven shaft 4 to slide and switch multiple output transmission paths in the output gear set 9.
[0069] Preferred, Reference Figure 13 The push-pull shaft body 61 is divided along its axial direction to form a plurality of splicable shaft bodies 613. A plurality of locking ring grooves 6131 are provided on the splicing shaft body 613. An elastic hoop 614 for radially limiting the splicing shaft body 613 is installed in the locking ring groove 6131.
[0070] In this embodiment, the push-pull shaft body 61 is composed of multiple interlocking shaft bodies 613, and the interlocking shaft bodies 613 are radially tightened by installing elastic rings 614 in locking ring grooves 6131. When the middle section is compressed, the compressive force overcomes the elastic force of the elastic rings 614, causing the interlocking shaft bodies 613 to separate radially, thereby expanding the inner diameter. This allows the telescopic shaft 512 to drive the locking protrusion 5121 to disengage from the locking groove 612 in the middle section of the push-pull shaft body 61 and slide along the telescopic through hole 611 to the next locking groove 612.
[0071] This invention divides the push-pull shaft body 61 along its axial direction to form multiple splicable shaft bodies 613. Multiple locking ring grooves 6131 are formed radially on the spliced shaft bodies 613, and elastic rings 614 are installed in the locking ring grooves 6131. When the middle section of the push-pull shaft body 61 is squeezed, the elastic force of the elastic rings 614 is offset by the squeezing force, and the multiple spliced shaft bodies 613 move radially outward to deform and complete the expansion of the telescopic through hole 611. The locking protrusion 5121 can disengage from the current locking groove 612, and the telescopic shaft 512 slides along the telescopic through hole 611 of the push-pull shaft body 61.
[0072] Preferred, Reference Figure 9 , Figure 11 The output gear set 9 includes a first output wheel 91 and a second output wheel that are sleeved on the driven shaft 4 and have different numbers of teeth. The output ratchet 8 is slidably disposed between the first output wheel 91 and the second output wheel 92 along the driven shaft 4, and the output ratchet 8 is meshed with the first output wheel 91 or the second output wheel 92.
[0073] In this embodiment, the output gear set 9 includes a first output wheel 91 and a second output wheel sleeved on the driven shaft 4, with different diameters. An output ratchet 8 is slidably disposed between the two, and both sides of the output ratchet 8 are provided with tooth grooves. Simultaneously, the first output wheel 91 and the second output wheel also have tooth grooves on the side near the output ratchet 8, allowing the output ratchet 8 to selectively engage with either the first output wheel 91 or the second output wheel. The output gear set 9 also includes an output assembly that is driven by the chainring 30, with both the first output wheel 91 and the second output wheel being driven by the output assembly.
[0074] This invention achieves output speed change by moving an output ratchet 8 to switch between two gears of different diameters. Compared to setting up multiple complex sliding gears or planetary gear sets to achieve output speed change, this design ensures the addition of one-dimensional (N3) speed change function while minimizing the number of parts, further controlling the final size and weight of the speed change device.
[0075] For further explanation, please refer to [reference]. Figure 9-11 , Figure 13-14 The inner wall of the telescopic through hole 611 is provided with a first locking groove 612a, a second locking groove 612b, a third locking groove 612c and a fourth locking groove 612d in sequence along the axis of the push-pull shaft body 61. The first locking groove 612a is located at the end of the push-pull shaft body 61 close to the drive cylinder 511, the fourth locking groove 612d is located at the other end of the push-pull shaft body 61 away from the drive cylinder 511, and the second locking groove 612b and the third locking groove 612c are located in the middle section of the push-pull shaft body 61.
[0076] Optional, see reference Figure 11 , Figure 12-14 When the output ratchet 8 is engaged with the second output wheel and the locking protrusion 5121 is positioned in the fourth locking slot 612d, the shifting protrusion 52 pushes the secondary clutch ratchet 41 at the third driven gear 73.
[0077] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the fourth locking slot 612d to the third locking slot 612c, the output ratchet 8 is engaged with the second output wheel and does not move. The thrust applied by the telescopic shaft 512 to the locking protrusion 5121 can counteract the elastic force of the elastic ring 614, causing the split shaft body 613 to separate. This causes the push-pull shaft body 61 to undergo radial deformation, expanding the diameter of the telescopic through hole 611. The locking protrusion 5121 disengages from the fourth locking slot 612d and slides along the telescopic through hole 611 to the third locking slot 612c. The shifting boss 52 also moves synchronously, disengaging from the clutch ratchet at the third driven gear 73 and pushing the clutch ratchet at the second driven gear 72, thus completing the gear shift from the third driven gear 73 to the second driven gear 72.
[0078] refer to Figure 11 , Figure 12-14When the telescopic shaft 512 moves the locking protrusion 5121 from the third locking slot 612c to the second locking slot 612b, the output ratchet 8 is engaged with the second output wheel and does not move. The push-pull shaft body 61 is subjected to force and undergoes radial deformation to expand the diameter of the telescopic through hole 611. The locking protrusion 5121 disengages from the third locking slot 612c and slides to the second locking slot 612b. The shifting boss 52 moves synchronously, but the moving distance is less than the axial length of the second-stage clutch ratchet 41, so that the shifting boss 52 continues to push the clutch ratchet at the second driven gear 72, and no gear shift occurs.
[0079] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the second locking slot 612b to the first locking slot 612a, the output ratchet 8 is engaged with the second output wheel and does not move. The push-pull shaft body 61 is subjected to force and undergoes radial deformation to expand the diameter of the telescopic through hole 611. The locking protrusion 5121 disengages from the second locking slot 612b and slides to the first locking slot 612a. The shifting boss 52 moves synchronously and pushes the secondary clutch ratchet 41 at the first driven gear 71 to complete the gear shift from the second driven gear 72 to the first driven gear 71.
[0080] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the first locking slot 612a away from the second locking slot 612b, one end of the push-pull shaft body 61 at the first locking slot 612a cannot undergo radial deformation. This causes the locking protrusion to move synchronously with the push-pull shaft body 61, which in turn causes the connecting shaft 62 to simultaneously drive the output ratchet 8 to slide along the driven shaft 4, separating it from the second output wheel and engaging with the first output wheel 91. The axial length of the sliding shaft is less than the axial length of the clutch ratchet, so that after the output ratchet 8 moves to the first output wheel 91, the connecting shaft 62 limits the movement of the drive cylinder 511, the telescopic shaft 512, and the push-pull shaft body 61, ensuring that the locking protrusion 5121 continuously pushes the secondary clutch ratchet 41 at the first driven gear 71. This completes the gear shift from the second output wheel to the first output wheel 91.
[0081] refer to Figure 11 , Figure 12-14 When the output ratchet 8 is engaged with the first output wheel 91 and the locking protrusion 5121 is positioned in the first locking groove 612a, the shifting protrusion 52 pushes the secondary clutch ratchet 41 at the first driven gear 71.
[0082] refer to Figure 11 , Figure 12-14When the telescopic shaft 512 moves the locking protrusion 5121 from the first locking slot 612a to the second locking slot 612b, the output ratchet 8 does not move, the push-pull shaft body 61 deforms, the locking protrusion 5121 disengages from the first locking slot 612a and slides to the second locking slot 612b, the shifting boss 52 moves synchronously and pushes the clutch ratchet at the second driven gear 72, completing the gear shift from the first driven gear 71 to the second driven gear 72.
[0083] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the second locking slot 612b to the third locking slot 612c, the output ratchet 8 is engaged with the first output wheel 91 and does not move. The push-pull shaft body 61 deforms and the locking protrusion 5121 disengages from the second locking slot 612b and slides to the third locking slot 612c. The shifting boss 52 moves synchronously, but the moving distance is less than the axial length of the secondary clutch ratchet 41, so that the shifting boss 52 continues to push the clutch ratchet at the second driven gear 72, and no gear shift occurs.
[0084] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the third locking slot 612c to the fourth locking slot 612d, the output ratchet 8 is engaged with the first output wheel 91 and does not move. The push-pull shaft body 61 deforms and the locking protrusion 5121 disengages from the third locking slot 612c and slides to the fourth locking slot 612d. The shifting boss 52 moves synchronously and pushes the secondary clutch ratchet 41 at the third driven gear 73 to complete the gear shift from the second driven gear 72 to the third driven gear 73.
[0085] refer to Figure 11 , Figure 12-14 When the telescopic shaft 512 moves the locking protrusion 5121 from the fourth locking slot 612d away from the third locking slot 612c, the other end of the push-pull shaft body 61 at the fourth locking slot 612d cannot undergo radial deformation. This causes the locking protrusion to drive the push-pull shaft body 61 to move synchronously. Consequently, the connecting shaft 62 synchronously drives the output ratchet 8 to slide along the driven shaft 4, separating it from the first output wheel 91 and engaging with the second output wheel. Since the axial length of the sliding shaft is less than the axial length of the clutch ratchet, after the output ratchet 8 moves to the second output wheel, the connecting shaft 62 limits the movement of the drive cylinder 511, the telescopic shaft 512, and the push-pull shaft body 61, thereby ensuring that the locking protrusion 5121 continuously pushes the secondary clutch ratchet 41 at the third driven gear 73. This completes the gear shift from the first output wheel 91 to the second output wheel, ultimately completing the gear shift cycle.
[0086] It should be noted that the structural design of the push-pull shaft body 61 is the core mechanical structure for achieving "selective linkage". Specifically, when the locking protrusion 5121 is located in the locking groove 612 in the middle section of the push-pull shaft body 61, pushing the telescopic shaft 512 will cause the middle part of the push-pull shaft body 61 to undergo elastic deformation due to its axial force, expanding the inner diameter. The locking protrusion 5121 can then disengage and slide to the next locking position. At this time, the push-pull shaft body 61 remains stationary, and the shifting boss 52 on the telescopic shaft 512 can move to disengage from pushing the current group of secondary clutch ratchet teeth 41 and push the next group of secondary clutch ratchet teeth 41, completing the gear shift. When the locking protrusion 5121 is located in the locking groove 612 of the end section, since the end does not deform, the axial force is directly transmitted to the push-pull shaft body 61 as the telescopic shaft continues to be pushed, causing it to move as a whole, thereby driving the output ratchet 8. At the same time, combined with the structural setting that the sliding distance of the output ratchet 8 is less than the length of the secondary clutch ratchet 41 along the axis, the output ratchet 8 moves but the shifting boss 52 moves synchronously to the next set of secondary clutch ratchet 41. This ingenious structure achieves the switching between "self-movement" and "pushing other objects" modes by only using the difference in deformation characteristics of a single push-pull shaft 6 in different sections. The structure is extremely ingenious and compact, avoiding the use of complex clutches or dual drive mechanisms, and making a significant contribution to reducing size and weight.
[0087] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.
Claims
1. A dual-shaft speed change device, characterized in that, include: The first shift assembly (1), multiple sets of first-stage clutch ratchet teeth (11), gear assembly (2) with multiple transmission path structures, and multi-stage main gear (3) sleeved on the gear assembly (2) are provided. The first shift assembly (1) can push any set of first-stage clutch ratchet teeth (11) to engage with the gear assembly (2), so that the corresponding transmission path structure drives the multi-stage main gear (3) to rotate. Driven shaft (4), multiple sets of two-stage clutch ratchet (41), a second shift assembly (5) movable within the driven shaft (4) and a push-pull shaft (6), and a multi-stage driven gear (7) sleeved on the driven shaft (4), an output ratchet (8) and an output gear set (9) with multiple output transmission paths. Moving the second shift assembly (5) can push any set of secondary clutch ratchet (41) protrusions to engage with the multi-stage driven gear (7), and the multi-stage main gear (3) meshes with the multi-stage driven gear (7) to drive the driven shaft (4) to rotate. When one end of the second shift assembly (5) extends into the push-pull shaft (6) and is located in the middle, moving the second shift assembly (5) can squeeze the push-pull shaft (6) to deform and expand the inner diameter, so that the second shift assembly (5) can slide to switch the engagement position; The push-pull shaft (6) is fixedly connected to the output ratchet (8), and when one end of the second shift assembly (5) is located at both ends of the push-pull shaft (6), moving the second shift assembly (5) can simultaneously move the push-pull shaft (6) and the output ratchet (8), so that the output ratchet (8) slides along the axial direction to transmit the corresponding output path structure.
2. The dual-shaft speed change device according to claim 1, characterized in that, The gear assembly (2) includes a first planetary set (21), a ratchet drive (22), and a second planetary set (23) fitted onto the first shift assembly (1). The first planetary set (21), the ratchet drive (22), and the second planetary set (23) are all independent transmission path structures and are all connected to the multi-stage main gear assembly (3) for transmission.
3. The dual-shaft speed change device according to claim 1, characterized in that, The multi-stage main gear component (3) includes a main gear seat (31) connected to the gear assembly (2), and a first main gear (32), a second main gear (33), and a third main gear (34) that are sequentially fixedly sleeved on the main gear seat (31) and have a decreasing number of teeth. The multi-stage driven gear component (7) includes a first driven gear (71), a second driven gear (72), and a third driven gear (73) that are rotatably mounted on the driven shaft (4) and have an increasing number of teeth. The first driven gear (71), the second driven gear (72), and the third driven gear (73) are respectively meshed with the first master gear (32), the second master gear (33), and the third master gear (34).
4. The dual-shaft speed change device according to claim 1, characterized in that, The second shift assembly (5) includes a shift push-pull shaft (51), on which a shift boss (52) is provided. Moving the shift push-pull shaft (51) axially can drive the shift boss (52) to move on the driven shaft (4), and can push any set of secondary clutch ratchet teeth (41) radially sliding protrusions to engage with the multi-stage driven gear (7).
5. The dual-shaft speed change device according to claim 4, characterized in that, The shift push-pull shaft (51) includes a drive cylinder (511) with one end externally connected to a drive device, and a telescopic shaft (512) with one end connected to the other end of the drive cylinder (511). The other end of the telescopic shaft (512) extends into the push-pull shaft component (6) and is slidably positioned.
6. The dual-shaft speed change device according to claim 5, characterized in that, The shift boss (52) is located at one end of the telescopic shaft (512). The other end of the telescopic shaft (512) can extend into the push-pull shaft (6) and be slidably locked with it. The shift boss (52) can abut against the push-pull shaft (6) to limit the depth of the telescopic shaft (512) extending into the push-pull shaft (6).
7. The dual-shaft speed change device according to claim 6, characterized in that, The push-pull shaft (6) includes a push-pull shaft body (61), and the push-pull shaft body (61) has a telescopic through hole (611) adapted to the telescopic shaft (512) along its axial direction. The middle section of the push-pull shaft body (61) can be radially deformed under axial force to expand the diameter of the telescopic through hole (611).
8. The dual-shaft speed change device according to claim 7, characterized in that, The inner wall of the telescopic through hole (611) is provided with a plurality of snap-fit grooves (612) spaced apart along its axial direction, and the snap-fit grooves (612) are formed by a radial recess along the push-pull shaft body (61). One end of the telescopic shaft (512) expands radially to form a locking protrusion (5121), which is locked and installed in the locking groove (612).
9. The dual-shaft speed changer according to claim 7 or 8, characterized in that, The push-pull shaft body (61) is divided along its axial direction to form a plurality of splicable shaft bodies (613). A plurality of locking ring grooves (6131) are provided on the splicing shaft body (613). An elastic hoop (614) for radially limiting the splicing shaft body (613) is installed in the locking ring groove (6131).
10. The dual-shaft speed change device according to claim 1, characterized in that, The output gear set (9) includes a first output wheel (91) and a second output wheel with different numbers of teeth, which are sleeved on the driven shaft (4). The output ratchet (8) is slidably disposed between the first output wheel (91) and the second output wheel along the driven shaft (4), and the output ratchet (8) is meshed with the first output wheel (91) or the second output wheel.