Speed reducer

Abstract

The speed reducer comprises a base, a wheel set frame, a driving shaft, an inner wheel set and an outer wheel, the wheel set frame is fixedly connected to the base, and the driving shaft is rotatably installed on the wheel set frame; the inner wheel set comprises a first gear and a second gear which are sequentially and eccentrically arranged on the driving shaft in the axial direction of the driving shaft, the circle center connecting line of the first gear and the second gear passes through the rotating center of the driving shaft, and outer teeth are jointly formed on the outer circumferential face of the first gear and the outer circumferential face of the second gear. Inner teeth meshed with the outer teeth are arranged on the inner circumferential face of the outer wheel, and a tooth number difference exists between the inner teeth and the outer teeth. According to the speed reducer, the rod piece of the wheel set frame penetrates through the first gear and the second gear in the axial direction of the driving shaft, the two ends of the rod piece are fixedly connected to the base, all-directional supporting of the inner wheel set is formed, the problem that rigidity is insufficient in a traditional cantilever assembling mode is effectively solved, and the speed reducer is more stable and reliable in overall structure and long in service life.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of speed reducers, in particular to a speed reducer with increased service life and reduced failure rate. BACKGROUND

[0002] In the prior art, as an indispensable key component in the modern industrial field, speed reducers are widely used in robots, precision machine tools, automation equipment, aerospace and other fields. The main function of the speed reducer is to reduce the speed of the power source such as a motor and increase the output torque to meet the needs of different application scenarios. According to the transmission principle and structural characteristics, the common precision speed reducers on the market mainly include planetary reducers, RV reducers and harmonic reducers.

[0003] Planetary reducers are widely used in general industrial fields due to their compact structure, high transmission efficiency and strong load capacity. However, traditional planetary reducers generally have a large backlash due to the existence of gear meshing gap, which is usually more than an arc minute. In high-precision control applications such as precision servo systems and robot joints, backlash can seriously affect transmission accuracy, positioning accuracy and dynamic response performance, making it difficult to meet the application requirements of high precision and high performance. In addition, when a high-precision planetary reducer is required, the manufacturing cost and maintenance difficulty will also increase significantly.

[0004] RV reducers adopt a structure combining planetary gears for pre-reduction and cycloid pin wheels for secondary reduction. Compared with planetary reducers, RV reducers have significant improvements in rigidity, impact resistance and transmission accuracy, and the backlash can be controlled to be more than 1 arc minute. Therefore, RV reducers are often used in industrial robot joints and other fields that require high precision and rigidity. However, the structure of RV reducers is relatively complex, and the machining precision of the components is high, resulting in high manufacturing cost and long production cycle, making it difficult to meet the needs of large-scale applications.

[0005] Harmonic reducers utilize the principle of flexible deformation for transmission, with advantages such as small size, light weight, large transmission ratio and high precision, and the backlash can be controlled to be less than 3 arc minutes, making them particularly suitable for applications sensitive to size and weight, such as lightweight robots, aerospace aircraft and precision instruments. However, harmonic reducers also have some inherent shortcomings, such as relatively low rigidity, poor impact resistance, easy fatigue of the flexspline, limited service life, and easy heating during high-speed operation. In addition, the manufacturing cost of harmonic reducers is also relatively high, and the load capacity is limited. CONTENT OF THE INVENTION

[0006] To solve the above problems, the present application provides a speed reducer with good rigidity, long service life and low failure rate.

[0007] In order to achieve the above object, the application discloses a speed reducer, which comprises a wheel set frame, a driving shaft, an inner wheel set and an outer wheel.

[0008] The inner wheel set comprises a first gear and a second gear which are sequentially arranged on the driving shaft in an eccentric manner along the axial direction of the driving shaft, the center line of the first gear and the second gear passes through the rotation center of the driving shaft, and the outer circumferential surface of the first gear and the second gear is provided with external teeth.

[0009] The inner circumferential surface of the outer wheel is provided with internal teeth which are engaged with the external teeth, and the internal teeth and the external teeth have a tooth number difference.

[0010] The wheel set frame comprises at least one rod member which passes through the first gear and the second gear along the axial direction of the driving shaft, both ends of the rod member are fixedly connected to the base, the first gear and the second gear are provided with mounting holes which are in position correspondence with the rod member, and the inner diameter of the mounting hole is greater than the outer diameter of the rod member.

[0011] Among them, one of the outer wheel and the wheel set frame is configured as the output end of the speed reducer, and the other is configured as the fixed end.

[0012] Further, the wheel set frame further comprises a first bearing, a first base and a second base which is oppositely arranged with the first base, one end of the driving shaft is fixedly connected to the inner ring of the first bearing through the first base, the outer ring of the first bearing is fixedly connected to the second base, and the first gear and the second gear are located between the first base and the second base; both ends of the rod member are fixedly connected to the first base and the second base, respectively.

[0013] Further, the rod member has opposite first and second ends, the rod member located at the circumferential rear side of the driving shaft is integrally formed with the first base through the first end, and the rod member located at the circumferential front side of the driving shaft is integrally formed with the second base through the second end; the first base is provided with a first insertion hole which is adapted to the first end of the rod member on the second base, and the second base is provided with a second insertion hole which is adapted to the second end of the rod member on the first base.

[0014] Further, the second end of the rod member on the first base is provided with a threaded hole which penetrates through the second base, and the second base is threadedly connected with the threaded hole of the rod member on the first base through a fastening screw.

[0015] Further, the first base and the second base are both provided with a second bearing which is coaxial with the outer wheel, and the outer ring of the second bearing is fixed on the inner circumferential surface of the outer wheel.

[0016] Further, a plurality of through holes are formed in the first gear and the second gear, and the through holes are arranged along the circumferential direction of the gears; the through holes corresponding in position on the first gear and the second gear at least partially overlap in the axial direction of the drive shaft to form the mounting hole.

[0017] Further, a spacer is provided, the spacer is sleeved on the drive shaft and can rotate relative to the drive shaft, the first gear and the second gear are fixedly connected on the spacer in sequence and eccentrically in the axial direction of the drive shaft; the spacer is provided with a fastener, the fastener is used to selectively fix the first gear and the second gear to the drive shaft to rotate together with the drive shaft, or release the first gear and the second gear to rotate relative to the drive shaft.

[0018] Further, two inner wheel sets are provided on the drive shaft, one of the inner wheel sets is fixedly connected to the drive shaft to rotate together with the drive shaft, and the other inner wheel set is selectively fixed to the drive shaft or released by the spacer.

[0019] Further, the drive shaft has an exposed part extending out of the spacer, the fastener is threadedly connected with the exposed part and has a pressing sleeve extending towards the spacer; the inner diameter of the pressing sleeve unidirectionally increases towards the side away from the fastener in the axial direction of the drive shaft, and a tapered pressing space is formed between the outer circumferential surface of the drive shaft and the pressing sleeve; one end of the spacer at least partially extends into the tapered pressing space; when the fastener is screwed, the pressing sleeve applies radial pressure to the spacer, so that the spacer is fixedly connected with the drive shaft.

[0020] Further, the end of the spacer extending into the tapered pressing space is provided with a guide inclined surface matched with the inner wall of the pressing sleeve, a plurality of deformation notches extending in the axial direction of the spacer are formed in the guide inclined surface, and the deformation notches enable the end of the spacer to elastically deform when subjected to radial pressure.

[0021] The reducer designed in the application forms all-around support for the inner wheel set through the rod member of the wheel set frame along the driving shaft axially through the first gear and the second gear, effectively solves the problem of insufficient rigidity in the traditional cantilever assembly mode, makes the overall structure of the reducer more stable and reliable; at the same time, the design that the inner diameter of the mounting hole arranged on the inner wheel set is greater than the outer diameter of the rod member not only ensures the effective positioning of the rod member to the inner wheel set, but also allows the inner wheel set to rotate relative to the rod member, enhances the overall rigidity of the reducer, significantly prolongs the service life of the equipment, reduces the failure rate in the running process, improves the stability and reliability of the reducer under high load conditions, makes it more suitable for application scenarios of long-time continuous work. In addition, the reducer adopts the gap adjusting member which can be selectively fixed or rotated relative to the driving shaft, so that the user only needs to release the fixed state of the gap adjusting member when necessary, and by slightly rotating the gap adjusting member, the meshing gap of the first gear and the second gear relative to the inner teeth of the outer wheel can be accurately controlled, the tooth side gap caused by manufacturing tolerance, assembly error or long-term running wear is effectively compensated, the problems such as reduction of transmission accuracy, increase of noise and reduction of work efficiency of the reducer caused by too large gear gap are avoided, thereby further improving the working performance and service life of the reducer. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a perspective structural schematic diagram of the reducer provided by the embodiment of the application.

[0023] Figure 2 is a working schematic diagram of the reducer provided by the embodiment of the application.

[0024] Figure 3 is Figure 2 a perspective exploded view.

[0025] Figure 4 is Figure 1 a perspective exploded view of

[0026] Figure 5 is a perspective structural schematic diagram of the gap adjusting member provided by the embodiment of the application.

[0027] Figure 6 is a plane structural schematic diagram of the reducer provided by the embodiment of the application

[0028] Figure 7 is Figure 6 a sectional view at the base-base of

[0029] Figure 8 is Figure 7 an enlarged schematic diagram at the base of

[0030] Figure 9 is Figure 6 a sectional view at the base-base of

[0031] Figure 10 is an axial plane structure schematic diagram of a speed reducer provided by an embodiment of the present application.

[0032] Figure 11 is Figure 10 a sectional view at D-D in FIG. 1.

[0033] wherein: the base 10, the external load 11, the frame 12, the wheel set frame 20, the first bearing 21, the first base 22, the first insertion hole 221, the second base 23, the second insertion hole 231, the fastening screw 24, the second bearing 25, the drive shaft 30, the exposed part 31, the inner wheel set 40, the first gear 41, the second gear 42, the third gear 43, the fourth gear 44, the outer wheel 50, the rod 60, the mounting hole 70, the through hole 80, the gap adjusting piece 90, the guide inclined surface 91, the deformation notch 92, the second groove structure 93, the fastener 100, the pressing sleeve 101, the conical pressing space 102. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, it should be understood that the preferred embodiments described here are only used to explain and illustrate the present application, and are not used to limit the present application.

[0035] As Figures 1 to 11 shown, the speed reducer described in the present embodiment mainly includes the wheel set frame 20, the drive shaft 30, the inner wheel set 40 and the outer wheel 50. The speed reducer realizes speed reduction transmission through the eccentric meshing between the inner wheel set 40 and the outer wheel 50. The speed reducer aims to improve the flexibility of its configuration, that is, according to the specific application requirements, any component of the outer wheel 50 or the wheel set frame 20 can be used as the fixed end (connected to the external support structure or the base) of the speed reducer, and the other component can be used as the output end (connected to the external load or the actuator). This means that the output end and the fixed end of the speed reducer can be the outer wheel and the wheel set frame which can be converted with each other.

[0036] In a preferred embodiment, as Figure 2 , Figure 3 shown, the speed reducer is fixedly connected to the base 10 or other external support structure through the wheel set frame 20: in this configuration, the wheel set frame 20 is fixedly connected to the base 10, serving as the support basis of the inner wheel set 40 and the outer wheel 50, and the drive shaft 30 is rotatably mounted on the wheel set frame 20 and configured to receive power input from the external driving device (such as a motor) to realize rotation relative to the fixed wheel set frame 20; at this time, the outer wheel 50 serves as the output end of the speed reducer, used to connect the external load 11 or other transmission mechanism. In the present embodiment, the outer wheel 50 generally has a circular ring shape, and the inner peripheral surface thereof is machined with an inner tooth of a hard tooth surface structure, which meshes with the outer tooth of the inner wheel set. In another example, in order to improve the carrying capacity and allow a certain deformation to adapt to the meshing, the outer wheel 50 can be made of a synchronous belt material, which has flexibility and wear resistance.

[0037] In another embodiment, the speed reducer can also be achieved by fixing the outer wheel 50 to an external support structure, for example by fixing the base 10 to the outer wheel 50. In this configuration, the outer wheel 50 acts as the fixed end of the speed reducer, while the drive shaft 30 continues to act as the input end, receiving power from an external driving device to achieve rotation relative to the fixed outer wheel 50; at this time, the wheel set frame 20 becomes the output end of the speed reducer, used to connect external loads or other components that need to be driven, that is, through the meshing transmission of the inner wheel set and the fixed outer wheel, the input rotation of the drive shaft will cause the wheel set frame 20 to produce a reduced rotation relative to the outer wheel, thereby achieving power output. This configuration of interchanging the fixed end and the output end greatly improves the flexibility and application range of the speed reducer design, making it able to adapt to a variety of different installation and transmission requirements.

[0038] As shown in Figure 3 , Figure 4 , the inner wheel set 40 includes a first gear 41 and a second gear 42 arranged eccentrically along the drive shaft 30 in sequence, and the center line of the first gear 41 and the second gear 42 passes through the rotation center of the drive shaft 30, and the first gear 41 and the second gear 42 have equal eccentricity. This symmetrical eccentric design ensures the balance of the inner wheel set 40 during rotation, effectively reducing vibration and noise. At the same time, the outer periphery of the first gear 41 and the second gear 42 forms an outer tooth; the inner periphery of the outer wheel 50 is provided with an inner tooth meshing with the outer tooth, and the inner tooth and the outer tooth have a tooth number difference. As shown in Figure 9 , due to the eccentric arrangement, the outer tooth is elliptical, with the long axis ends tightly meshing with the inner tooth, and the short axis ends being disengaged or maintaining a large gap with the inner tooth, so that when the drive shaft 30 drives the outer tooth to rotate, the outer wheel 50 will produce a small angular displacement corresponding to the tooth number difference through the meshing of the inner tooth and the outer tooth, thereby achieving speed reduction output.

[0039] As shown in Figure 4 , Figure 11 , the wheel set frame 20 includes at least one rod 60 that passes through the first gear 41 and the second gear 42 along the drive shaft 30, both ends of the rod 60 are fixedly connected to the base 10, and the first gear 41 and the second gear 42 are provided with mounting holes 70 corresponding to the position of the rod 60, and the inner diameter of the mounting hole 70 is greater than the outer diameter of the rod 60. Since the inner diameter of the mounting hole 70 is greater than the outer diameter of the rod 60, the first gear 41 and the second gear 42 can rotate without interfering with the rod 60, and the supporting effect of the rod 60 effectively improves the rigidity and structural stability of the entire speed reducer. In this embodiment, the number of rods 60 is preferably six, and they are uniformly distributed along the circumference of the drive shaft 30 to provide more balanced and stable support force.

[0040] In some embodiments, as shown in Figure 4 , Figure 7 , Figure 11 The wheel set frame 20 also includes a first bearing 21, a first base 22 and a second base 23 opposite to the first base 22, one end of the drive shaft 30 is fixedly connected with the inner ring of the first bearing 21 through the first base 22, the outer ring of the first bearing 21 is fixedly connected on the second base 23, and the first gear 41 and the second gear 42 are located between the first base 22 and the second base 23; both ends of the rod member 60 are fixedly connected to the first base 22 and the second base 23 respectively, and the first base 22 and the second base 23 are fixedly connected to the base 10. In this way, a whole support frame is formed by the first base 22 and the second base 23, and the first gear 41 and the second gear 42 are arranged in the space between the first base 22 and the second base 23, so that the overall structure of the speed reducer is more compact, and since the inner ring of the first bearing 21 is fixedly connected with the drive shaft 30 and the outer ring is fixedly connected with the second base 23, the drive shaft 30 can rotate freely under the support of the bearing, while effectively reducing friction loss and operating noise. In the specific implementation process, as shown in Figure 2 , Figure 3 The base 10 can be pre-provided with a rack 12 for installing external driving devices such as driving motors, the first base 22 can be installed on the rack 12 through common connecting members such as bolts, and the second base 23 can be directly fixedly installed on the base 10 through connecting members such as bolts and kept opposite to the first base 22.

[0041] In some embodiments, as shown in Figure 3 , Figure 4 , Figure 11 The rod member 60 has opposite first and second ends 81 and 82, wherein the rod member 60 located on the circumferential rear side of the drive shaft 30 is integrally formed with the first base 22 through the first end 81 thereof, and the rod member 60 located on the circumferential front side of the drive shaft 30 is integrally formed with the second base 23 through the second end 82 thereof; the first base 22 is provided with a first insertion hole 221 adapted to the first end 81 of the rod member 60 on the second base 23, and the second base 23 is provided with a second insertion hole 231 adapted to the second end 82 of the rod member 60 on the first base 22. In this embodiment, three of the six rod members 60 are integrally formed with the first base 22, and the other three rod members 60 are integrally formed with the second base 23. During assembly, the first base 22 is first fixed on the rack 12, then the inner wheel set 40 is assembled on the drive shaft 30, and then the second base 23 is inserted into the alignment mounting hole 70 through the rod member 60 until it is inserted into the first insertion hole 221. At this time, the rod member 60 on the first base 22 is inserted into the second insertion hole 231, forming a cross-supporting structure that can effectively resist loads and vibrations from all directions, and the structure is simple and easy to assemble, effectively improving the strength and rigidity of the structure.

[0042] In some embodiments, as shown in Figure 4 , Figure 9 the second end 82 of the rod 60 on the first base 22 is provided with a threaded hole 222 penetrating the second base 23, and the second base 23 is threadedly connected to the threaded hole 222 of the rod 60 on the first base 22 by a fastening screw 24. The threaded connection can provide sufficient connection strength, further ensuring the stable connection between the first base 22 and the second base 23, and it is not easy to loosen even in the case of impact or vibration of the whole reducer.

[0043] In some embodiments, as shown in Figure 4 , Figure 7 , Figure 11 the first base 22 and the second base 23 are both provided with a second bearing 25 coaxial with the outer wheel 50, and the outer ring of the second bearing 25 is fixed on the inner circumferential surface of the outer wheel 50. In this embodiment, the outer wheel 50 constitutes an output end, and a flange or other connecting mechanism can be provided thereon to facilitate connection with other components, such as the joints of a robot, the worktable of a machine tool, etc. When the reducer is working, the outer teeth of the outer wheel 50 are driven to rotate by the corresponding outer teeth of the third gear 43 and the fourth gear 44, and the outer wheel 50 transmits the reduced rotary motion to the external load stably and accurately through the support of the second bearing 25.

[0044] In some embodiments, as shown in Figure 4 , Figure 9 a plurality of through holes 80 are formed on the first gear 41 and the second gear 42, and the through holes 80 are arranged at intervals along the circumferential direction of the respective gears; the positionally corresponding through holes 80 of the first gear 41 and the second gear 42 at least partially coincide in the axial direction of the drive shaft 30 to form a mounting hole 70. The provision of the through holes 80 not only forms the mounting hole 70 for mounting the rod 60, but also reduces the amount of material used, meeting the demand for lightweight.

[0045] In some embodiments, as shown in Figure 3 , Figure 4 , Figure 5 , Figure 7As shown, the adjusting piece 90 is sleeved on the drive shaft 30 and can rotate relative to the drive shaft 30, the first gear 41 and the second gear 42 are fixedly connected on the adjusting piece 90 in sequence and eccentrically along the axial direction of the drive shaft 30; the adjusting piece 90 is provided with a fastener 100, which is used to selectively fix the first gear 41 and the second gear 42 to the drive shaft 30 to rotate together with the drive shaft 30, or release the first gear 41 and the second gear 42 to rotate relative to the drive shaft 30. In actual application, when the backlash of the reducer increases, the transmission accuracy decreases or the reverse backlash occurs after long-term use, exemplarily: first, loosen the fastener 100 to release the first gear 41 and the second gear 42; second, rotate the first gear 41 and the second gear 42 by a small amplitude through a tool, change the relative position angle of the long shaft of the external tooth and the drive shaft 30, so that the tooth surface at both ends of the long shaft of the external tooth can be more tightly abutted against the tooth surface of the corresponding tooth on the internal tooth; finally, while maintaining the optimal meshing state, lock the fastener 100 again. Through this simple adjustment method, the backlash caused by long-term operation of the gear wear is effectively eliminated, and the high precision and stability of the transmission system are maintained.

[0046] In some embodiments, as shown in Figure 3 、 Figure 4 、 Figure 7 As shown, the inner wheel set 40 is provided with two on the drive shaft 30, one of which is fixedly connected to the drive shaft 30 to rotate together with the drive shaft 30, and the other is selectively fixed to the drive shaft 30 or released by the adjusting piece 90. Exemplarily: the inner wheel set 40 fixedly connected to the drive shaft 30 includes the third gear 43 and the fourth gear 44, that is, the third gear 43 and the fourth gear 44 are directly fixed on the drive shaft 30 and cannot rotate relative to the drive shaft 30, but rotate together with the drive shaft 30:

[0047] Thus, on one hand, the outer teeth of the two inner wheel sets 40 jointly act on the inner teeth to disperse the load, so that each gear bears less force and can bear greater torque; on the other hand, when the first gear 41 and the second gear 42 are released by the fastener 100 and the first gear 41 and the second gear 42 are rotated clockwise to change the relative position angle of the long axis of the corresponding outer teeth and the drive shaft 30, the outer wheel 50 will rotate clockwise by a corresponding angle in response to the adjustment, and in the counterclockwise direction, the rotation of the outer wheel 50 will be limited by the corresponding outer teeth of the third gear 43 and the fourth gear 44, because the tooth surfaces at both ends of the long axis of the corresponding outer teeth of the third gear 43 and the fourth gear 44 can tightly abut against the counterclockwise tooth surfaces of the corresponding teeth on the inner teeth. In addition, after the adjustment is completed, the long axis of the outer teeth and the long axis of the corresponding outer teeth of the third gear 43 and the fourth gear 44 are no longer parallel in the axial direction of the drive shaft 30, but are distributed in a staggered manner in the axial direction of the drive shaft 30, which ensures that after the tooth gap elimination operation is completed, no matter whether the drive shaft 30 is output in the forward direction or in the reverse direction, the outer teeth formed by the first gear 41 and the second gear 42 and the corresponding outer teeth of the third gear 43 and the fourth gear 44 can be tightly engaged with the inner teeth, completely eliminating the idling stroke of each gear, ensuring that there is no gap in the forward and reverse rotation directions of the first gear 41, the second gear 42, the third gear 43 and the fourth gear 44, and realizing zero-backlash transmission.

[0048] In some embodiments, as shown in Figure 7 、 Figure 8 、 Figure 11 The drive shaft 30 has an exposed part 31 extending out of the tooth gap adjusting member 11, the fastener 100 is threadedly connected with the exposed part 31 and has a pressing sleeve 101 extending towards the tooth gap adjusting member 11; the inner diameter of the pressing sleeve 101 unidirectionally increases towards the side away from the fastener 100 in the axial direction of the drive shaft 30, and forms a tapered pressing space 102 with the outer circumferential surface of the drive shaft 30; one end of the tooth gap adjusting member 11 at least partially extends into the tapered pressing space 102; when the fastener 100 is tightened, the pressing sleeve 101 applies radial pressure to the tooth gap adjusting member 11, so that the tooth gap adjusting member 11 is connected and fixed with the drive shaft 30. In actual operation, when it is necessary to adjust the tooth gap, the radial pressure of the pressing sleeve 101 on the tooth gap adjusting member 11 can be released by loosening the fastener 100, for example, a locking nut, so that the tooth gap adjusting member 11 can rotate freely relative to the drive shaft 30 to adjust the tooth gap; after the adjustment is completed, the tooth gap adjusting member 11 can be fixed on the drive shaft 30 again by tightening the fastener 100, so as to restore the normal working state of the speed reducer. This tapered pressing sleeve fastening structure makes the tooth gap adjustment operation more convenient and reliable, and can maintain stable connection performance for a long time.

[0049] In some embodiments, as shown in Figure 5 、 Figure 8As shown, the end of the adjustment piece 11 extending into the tapered compression space 102 is provided with a guide slope 91 matching the inner wall of the compression sleeve 101, which can well fit the inner wall of the compression sleeve 101 during assembly and provide assembly guidance. A plurality of deformation notches 92 extending along the axial direction of the adjustment piece 11 are formed on the guide slope 91, which enables the end of the adjustment piece 11 to elastically deform when subjected to radial pressure. In the embodiment, preferably, three or four deformation notches 92 are circumferentially distributed to reduce the local stiffness of the end of the adjustment piece 11 and make it a weak area of elastic deformation. When the fastener 100 is tightened and the compression sleeve 101 exerts radial pressure on the adjustment piece 11, the end of the adjustment piece 11 elastically deforms under the action of the radial pressure due to the presence of the deformation notches 92, which enables the end of the adjustment piece 11 to better fit the outer circumferential surface of the drive shaft 30, increases the actual contact area, and realizes more uniform radial pressure distribution, thereby significantly improving the clamping effect and connection reliability.

[0050] In a specific example, as shown in Figure 1 、 Figure 5 、 Figure 8 As shown, the outer surface of the fastener 100 is provided with a first groove structure, which can be a hexagonal socket provided on the outer surface of the fastener 100 or other applicable tool interface forms for external tools to be tightened. The end of the deformation notch 92 is provided with a second groove structure 93, which is specifically a through hole provided at the axial end of the deformation notch 92 in the embodiment, which can cooperate with a tool such as a pin wrench or a pin wrench to realize fine adjustment of the adjustment piece 11 relative to the drive shaft 30.

[0051] The speed reducer provided by the embodiment forms all-around support for the inner wheel set through the rod member of the wheel set frame axially penetrating the first gear and the second gear along the driving shaft and being fixedly connected to the base at both ends, effectively solves the problem of insufficient rigidity in the traditional cantilever assembly mode, and makes the overall structure of the speed reducer more stable and reliable; meanwhile, the design that the inner diameter of the mounting hole arranged on the inner wheel set is larger than the outer diameter of the rod member not only ensures effective positioning of the rod member on the inner wheel set, but also allows the inner wheel set to rotate relative to the rod member, enhances the overall rigidity of the speed reducer, significantly prolongs the service life of the equipment, reduces the failure rate in the running process, improves the stability and reliability of the speed reducer under high load conditions, and makes the speed reducer more suitable for application scenarios of long-time continuous work. In addition, the speed reducer adopts the gap adjusting member that can be selectively fixed or rotated relative to the driving shaft, so that the user only needs to release the fixed state of the gap adjusting member when necessary, and can accurately control the meshing gap of the first gear and the second gear relative to the inner teeth of the outer wheel by slightly rotating the gap adjusting member, effectively compensates for the tooth side gap caused by manufacturing tolerances, assembly errors or long-term running wear, avoids problems such as reduction of transmission accuracy, increase of noise and reduction of work efficiency of the speed reducer caused by too large gear gap, and further improves the working performance and service life of the speed reducer.

[0052] In the description of the present application, it should be pointed out that the orientation or positional relationship indicated by the terms "vertical", "upper", "lower", "horizontal" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0053] In the description of the present application, it should be pointed out that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0054] Finally, it should be pointed out that: the above only describes the preferred embodiments of the present application, and is not used to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A speed reducer characterized by, The wheel set frame, the drive shaft, the inner wheel set and the outer wheel, the drive shaft is rotatably mounted on the wheel set frame; The inner wheel set comprises a first gear and a second gear which are eccentrically arranged on the drive shaft in sequence along the axial direction of the drive shaft, the center line of the first gear and the second gear passes through the rotation center of the drive shaft, and the outer circumferential surface of the first gear and the second gear jointly forms an outer gear; The inner circumferential surface of the outer wheel is provided with an inner gear which is engaged with the outer gear, and the inner gear and the outer gear have a difference in the number of teeth; The wheel set frame comprises at least one rod member which passes through the first gear and the second gear along the axial direction of the drive shaft, the first gear and the second gear are provided with mounting holes which correspond to the position of the rod member, and the inner diameter of the mounting hole is larger than the outer diameter of the rod member; One of the outer wheel and the wheel set frame is configured as the output end of the speed reducer, and the other is configured as the fixed end.

2. The speed reducer according to claim 1, characterized by The wheel set frame further comprises a first bearing, a first base and a second base which is oppositely arranged with the first base, one end of the drive shaft is fixedly connected with the inner ring of the first bearing through the first base, the outer ring of the first bearing is fixedly connected on the second base, and the first gear and the second gear are located between the first base and the second base; the two ends of the rod member are fixedly connected to the first base and the second base respectively.

3. The speed reducer according to claim 2, characterized by The rod member has opposite first end and second end, the rod member located at the circumferential rear side of the drive shaft is integrally formed with the first base through the first end, and the rod member located at the circumferential front side of the drive shaft is integrally formed with the second base through the second end; the first base is provided with a first insertion hole which is matched with the first end of the rod member on the second base, and the second base is provided with a second insertion hole which is matched with the second end of the rod member on the first base.

4. The speed reducer according to claim 3, characterized by The second end of the rod member on the first base is provided with a screw hole which penetrates through the second base, and the second base is threadedly connected with the screw hole of the rod member on the first base through a fastening screw.

5. The speed reducer of claim 2, wherein The first base and the second base are both provided with a second bearing which is coaxial with the outer wheel, and the outer ring of the second bearing is fixed on the inner circumferential surface of the outer wheel.

6. The speed reducer of claim 1, wherein The first gear and the second gear are both provided with a plurality of through holes which are arranged at intervals along the circumferential direction of each gear; the position corresponding through holes on the first gear and the second gear at least partially coincide in the axial direction of the drive shaft to form the mounting hole.

7. The speed reducer according to any one of claims 1 to 6, characterized by Further comprising a gap adjusting member which is sleeved on the drive shaft and can rotate relative to the drive shaft, the first gear and the second gear are fixedly connected on the gap adjusting member in sequence along the axial direction of the drive shaft; The gap adjusting member is provided with a fastener which is used for selectively fixing the first gear and the second gear to the drive shaft to jointly rotate with the drive shaft, or releasing the first gear and the second gear to enable them to rotate relative to the drive shaft.

8. The speed reducer of claim 7, wherein The inner wheel group is provided with two on the drive shaft, one of which is fixedly connected to the drive shaft to rotate together with the drive shaft, and the other is selectively fixed to the drive shaft or released by the adjustment piece.

9. The speed reducer of claim 7, wherein The drive shaft has an exposed part extending out of the adjustment piece, the fastener is threadedly connected with the exposed part and has a pressing sleeve extending towards the adjustment piece; the inner diameter of the pressing sleeve unidirectionally increases towards the side away from the fastener in the axial direction of the drive shaft, and forms a tapered pressing space with the outer peripheral surface of the drive shaft; one end of the adjustment piece at least partially extends into the tapered pressing space; when the fastener is tightened, the pressing sleeve applies radial pressure to the adjustment piece, so that the adjustment piece is fixedly connected with the drive shaft.

10. The speed reducer of claim 9, wherein The end of the adjustment piece extending into the tapered pressing space is provided with a guide slope matched with the inner wall of the pressing sleeve, a plurality of deformation notches extending in the axial direction of the adjustment piece are formed on the guide slope, and the deformation notches enable the end of the adjustment piece to elastically deform when subjected to radial pressure.

Images