CN115451115A

CN115451115A - Zero tooth clearance is from regulation structure RV speed reducer

Info

Publication number: CN115451115A
Application number: CN202211257934.4A
Authority: CN
Inventors: 顾京君; 邢海; 陈树君; 郭志强
Original assignee: NANTONG ZHENKANG MACHINERY CO Ltd; Nantong Zhenkang Welding Electromachinery Co ltd
Current assignee: NANTONG ZHENKANG MACHINERY CO Ltd; Nantong Zhenkang Welding Electromachinery Co ltd
Priority date: 2022-10-13
Filing date: 2022-10-13
Publication date: 2022-12-09

Abstract

The invention provides a zero-backlash self-adjusting structure RV speed reducer, which relates to the technical field of speed reducers and comprises a pin gear shell, an output shaft, an output end cover, an input shaft and an eccentric shaft, wherein a bevel gear cycloid wheel is installed on an eccentric cam of the eccentric shaft; the inner wall of the needle gear shell is circumferentially arrayed with a plurality of conical semicircular grooves, rolling needles are assembled in the conical semicircular grooves, and the outer wall of the conical tooth cycloidal gear is circumferentially arrayed with a plurality of conical outer teeth meshed with the rolling needles and the conical teeth; an output anti-backlash structure is arranged at one end of the eccentric shaft close to the output shaft, and drives the eccentric shaft to integrally deviate along the axial direction of the eccentric shaft; an input anti-backlash structure is arranged at one end, close to the output end cover, of the eccentric shaft, and the input anti-backlash structure drives the bevel gear planet gear to deflect relative to the eccentric shaft along the axis of the bevel gear planet gear. The invention has the characteristics of elastic anti-backlash capability, zero backlash, long service life, high precision, low vibration and the like.

Description

Zero-backlash self-adjusting structure RV speed reducer

Technical Field

The invention relates to the technical field of speed reducers, in particular to a zero-backlash self-adjusting structure RV speed reducer.

Background

Certain tooth gaps are generally reserved for gear transmission inside the speed reducer, so that errors such as machining and assembling are prevented, the phenomenon that teeth are clamped in the tooth meshing process in the transmission process or lubrication is met is avoided. When the teeth are meshed with the teeth, due to the existence of tooth gaps and the existence of machining and assembling errors, discontinuity of a gear meshing transmission process can be caused, and vibration and transmission deviation are caused.

In addition, a plurality of friction pairs are arranged in the speed reducer, such as friction between a bearing rolling body and an inner ring and friction between inner teeth of a pin gear shell and outer teeth of a cycloid wheel during meshing transmission, and the like, and even if the speed reducer runs for a long time, certain abrasion cannot be avoided among all parts. When the abrasion value reaches a certain amount, the tooth clearance of the speed reducer is increased, particularly the tooth clearance of an RV speed reducer used in a robot joint is increased, if the tooth clearance is increased, the origin of the robot is drifted, and the track precision of the robot is reduced.

Disclosure of Invention

The invention aims to provide a zero-backlash self-adjusting structure RV speed reducer, which has elastic backlash eliminating capability by arranging bevel gear matching and arranging an input backlash eliminating structure and an output backlash eliminating structure at two ends of an eccentric shaft, not only can eliminate the adverse effect of a meshing process caused by processing and assembling errors, but also can eliminate the backlash increased by a certain amount of abrasion value after the speed reducer runs for a long time, so that the speed reducer can still maintain zero backlash, high precision, high rigidity and low vibration after certain abrasion occurs.

The technical purpose of the invention is realized by the following technical scheme:

a zero-backlash self-adjusting structure RV speed reducer comprises a needle gear shell, an output shaft, an output end cover, an input shaft and at least two eccentric shafts arranged in a circumferential array, wherein two eccentric cams of each eccentric shaft are respectively provided with a bevel cycloidal gear, one end of each eccentric shaft, which is close to the output end cover, is provided with a bevel planet gear in a limiting manner, the end part of each input shaft is provided with an input bevel gear, and the input bevel gear is meshed with the bevel planet gear in a bevel gear manner; the inner wall of the needle gear shell is circumferentially arrayed with a plurality of conical semicircular grooves, needle rollers matched with the conical semicircular grooves are assembled in the conical semicircular grooves, and the outer wall of the conical tooth cycloidal gear is circumferentially arrayed with a plurality of conical outer teeth meshed with the needle rollers and the conical teeth; an output anti-backlash structure is arranged at one end, close to the output shaft, of the eccentric shaft, and the output anti-backlash structure drives the eccentric shaft to drive the whole bevel-tooth cycloidal gear to axially deviate; an input anti-backlash structure is arranged at one end, close to the output end cover, of the eccentric shaft, and the input anti-backlash structure drives the bevel gear planet gear to deflect relative to the eccentric shaft along the axis of the bevel gear planet gear.

By adopting the technical scheme, the conical outer teeth on the outer wall of the conical-tooth cycloidal gear are meshed with the conical teeth between the rolling needles, after a gap exists between the conical-tooth cycloidal gear and the rolling needles, the output gap eliminating structure drives the eccentric shaft to wholly deviate along the axial direction of the eccentric shaft, and in the process that the eccentric shaft drives the cycloidal gear to move along the axial direction of the eccentric shaft, the conical outer teeth of the conical-tooth cycloidal gear and the rolling needles are tightly meshed under the conical meshing action, so that the meshing gap between the conical outer teeth and the rolling needles is eliminated. Similarly, the bevel gear meshes with the input bevel gear, after there is the clearance between bevel gear planet wheel and the input bevel gear, the relative eccentric shaft skew of input clearance structure drive bevel gear planet wheel along its axis, at the in-process that bevel gear planet wheel squinted along the eccentric shaft for bevel gear planet wheel and input bevel gear tightly mesh under the toper meshing effect, thereby eliminate the clearance between the two.

According to the invention, the output anti-backlash structure and the input anti-backlash structure are respectively arranged at the two ends of the eccentric shaft, so that the backlash between the side bevel cycloid gear and the needle roller at each position and the backlash between the input side bevel planetary gear and the input bevel gear can be eliminated, and the zero backlash is realized. The structure can eliminate the meshing clearance caused by abrasion, prolong the service life of the speed reducer, improve the transmission precision of the speed reducer and greatly reduce the vibration of the speed reducer during operation due to the improvement of the meshing condition, so the invention has the characteristics of zero tooth clearance, long service life, high precision, low vibration and the like.

Furthermore, the output anti-backlash structure comprises a first sealing cover arranged on the output shaft, the first sealing cover is positioned in a round hole of the output shaft for mounting the eccentric shaft, and a first butterfly-shaped elastic sheet matched with the end part of the eccentric shaft is arranged on one side, close to the eccentric shaft, of the first sealing cover.

By adopting the technical scheme, the first butterfly-shaped elastic sheet is pre-pressed for a certain deformation amount by locking the first sealing cover, the eccentric shaft drives the conical outer teeth of the bevel-tooth cycloidal gear to be tightly meshed with the roller pins by utilizing the elasticity of the first butterfly-shaped elastic sheet, and the meshing gap between the bevel-tooth cycloidal gear and the roller pins is eliminated elastically. And because first butterfly shell fragment has elasticity for awl tooth cycloid wheel one side has certain deformability, when awl tooth cycloid wheel and kingpin meshing, can not appear the dead condition of card emergence among the meshing process because of errors such as processing and assembly, and its simple structure, convenient operation and effect are obvious.

Furthermore, one side, far away from the first closing cap, of the first butterfly-shaped elastic sheet is provided with a first cushion block, one side, far away from the first butterfly-shaped elastic sheet, of the first cushion block is provided with a ball, and the ball is in rolling fit with the end part of the eccentric shaft.

By adopting the technical scheme, the abrasion of the eccentric shaft caused by high-speed rotation of the eccentric shaft to the first butterfly-shaped elastic sheet is reduced by utilizing the rolling fit of the ball and the eccentric shaft, the ball is installed and separated from the first butterfly-shaped elastic sheet by the first cushion block, the working effect and the service life of the first butterfly-shaped elastic sheet are ensured, and the structure is simple and the effect is obvious.

Furthermore, one side of the first cushion block, which is far away from the first butterfly-shaped elastic sheet, is provided with a rolling ring groove which is coaxial with the eccentric shaft, and the balls are arranged in the rolling ring groove along the circumferential array of the rolling ring groove and are all positioned and rolled and installed in the rolling ring groove.

By adopting the technical scheme, the rolling ball is installed in the rolling ring groove in a rolling way, so that the positioning and rolling installation of the rolling ball is realized, the rolling ball is prevented from being separated in the rolling process, and the rolling matching effect between the rolling ball and the end part of the eccentric shaft is ensured. Wherein, ball circumference array is equipped with a plurality of, sets up the rolling friction effect of a plurality of ball dispersion eccentric shafts to the ball, improves the result of use and the life of ball, and its simple structure and effect are obvious.

Furthermore, the first sealing cover is locked and pre-pressed with a first butterfly-shaped elastic sheet, the end part of the eccentric shaft is propped against the first butterfly-shaped elastic sheet through a first cushion block and a ball, the eccentric shaft drives the bevel-tooth cycloidal gear to move synchronously, and the conical outer teeth of the bevel-tooth cycloidal gear are tightly meshed with the roller pins, so that the tooth gaps between the bevel-tooth cycloidal gear and the roller pins are eliminated elastically.

By adopting the technical scheme, the first butterfly-shaped elastic sheet is pre-pressed for a certain deformation amount by locking the first sealing cover, so that the balls are propped against the end part of the eccentric shaft by the first cushion block, the eccentric shaft drives the bevel-tooth cycloidal gear to synchronously move, the conical outer teeth of the bevel-tooth cycloidal gear are tightly meshed with the roller pins, and the meshing gap between the bevel-tooth cycloidal gear and the roller pins is elastically eliminated. And because the elasticity of first butterfly shell fragment for awl tooth cycloid wheel one side has certain deformability, when awl tooth cycloid wheel and kingpin meshing, can not appear taking place the card dead condition because of errors such as processing and assembly and shut the condition.

Furthermore, the bevel gear planet wheel is arranged at one end of the eccentric shaft through a spline, the input bevel gear is arranged on the input shaft through a spline, and a second cushion block is arranged on one side, close to the output end cover, of the input bevel gear; the input gap eliminating structure comprises a second butterfly-shaped elastic piece arranged on one side, away from the bevel-tooth cycloidal gear, of the bevel-tooth planetary gear, a nut used for locking the second butterfly-shaped elastic piece on the eccentric shaft is arranged on one side, away from the bevel-tooth planetary gear, of the second butterfly-shaped elastic piece, and a shaft check ring is arranged on one side, away from the second butterfly-shaped elastic piece, of the bevel-tooth planetary gear.

Through adopting above-mentioned technical scheme, input bevel gear passes through the spline to be installed on the input shaft and realizes fixing input bevel gear through the second cushion, and the bevel gear planet wheel passes through the spline to be installed on the eccentric wheel, makes second butterfly shell fragment precompression a quantitative through adjusting the nut, applies certain power along its axial to the bevel gear planet wheel for bevel gear planet wheel and input bevel gear closely mesh, thereby eliminate the backlash between the two. And because second butterfly shell fragment has elasticity for the bevel gear planet wheel has certain deformability, when bevel gear planet wheel and input bevel gear meshing, can not appear because of errors such as processing and assembly meshing in-process and take place the card condition of dying.

Furthermore, the nut is locked and pre-pressed on the second butterfly-shaped elastic sheet, the outer teeth of the bevel gear planet wheel are tightly meshed with the outer teeth of the input bevel gear under the elastic action of the second butterfly-shaped elastic sheet, and the backlash between the bevel gear planet wheel and the input bevel gear is eliminated elastically.

By adopting the technical scheme, the second butterfly-shaped elastic sheet is pre-compressed by a certain amount by adjusting the nut, and a certain force along the axial direction of the second butterfly-shaped elastic sheet is applied to the bevel gear planet wheel, so that the bevel gear planet wheel is tightly meshed with the input bevel gear, and the backlash between the bevel gear planet wheel and the input bevel gear is eliminated. And because the elasticity of second butterfly shell fragment for the awl tooth planet wheel has certain deformability, when awl tooth planet wheel and input bevel gear meshing, can not take place the card dead condition because of errors such as processing and assembly appear in the meshing process.

Further, mounting bearings are respectively arranged between the outer circle of the output shaft, the outer circle of the output end cover and the inner circle of the pin gear shell, and the mounting bearings are one of tapered roller bearings, angular contact ball bearings or deep groove ball bearings; and a skeleton sealing ring is arranged between the output shaft and the needle gear shell, and the skeleton sealing ring is positioned on one side, which is far away from the output end cover, of the mounting bearing close to the skeleton sealing ring.

By adopting the technical scheme, the output shaft and the output end cover are arranged on the pin gear shell through the mounting bearing, the assembly consisting of the output shaft and the output end cover can do relative rotation movement with the pin gear shell, the framework sealing ring is arranged between the output shaft and the pin gear shell, the sealing between the output shaft and the pin gear shell is realized, and the sealing performance of the speed reducer is improved.

Furthermore, each bevel cycloid wheel is installed on a corresponding cam on the eccentric shaft through two groups of double-row tapered rollers arranged in a plurality of circumferential arrays, and the outer wall of the cam of the eccentric shaft and the inner wall of the bevel cycloid wheel are respectively used as an inner ring and an outer ring of the double-row tapered rollers in limited installation.

By adopting the technical scheme, the bevel-tooth cycloid wheel is respectively installed on the cam of the eccentric shaft through the double-row tapered rollers, the outer wall of the cam of the eccentric shaft and the outer wall of the bevel-tooth cycloid wheel are respectively used as the inner ring and the outer ring of the double-row tapered roller for limiting installation, the double-row tapered rollers are limited and installed between the outer wall and the inner wall, and the double-row tapered roller bearing is formed. Wherein, every awl tooth cycloid wheel corresponds double-row tapered roller, and one of double-row tapered roller is arranged in realizing the installation of awl tooth cycloid wheel, guarantees that the eccentric shaft can drive awl tooth cycloid wheel simultaneous movement for awl tooth cycloid wheel can closely mesh with the kingpin, and another row is used for offsetting the unilateral atress of awl tooth cycloid wheel, avoids arousing overall structure's unstability.

Furthermore, two ends of the input shaft are respectively installed on the output shaft and the output end cover through first tapered roller bearings, outer rings of the two first tapered roller bearings are respectively fixed through holes by using snap springs, and the two holes are positioned on one sides, far away from each other, of the two first tapered roller bearings by using the snap springs; the outer wall of the input shaft is provided with a limiting step, and the inner ring of the first tapered roller bearing is clamped on the limiting step.

Through adopting above-mentioned technical scheme, utilize two first tapered roller bearings to realize installing the rotation between input shaft and output shaft and the output end cover, and under the spacing fixed action of jump ring and spacing step for the hole, realize the spacing fixed to two first tapered roller bearing inner rings and outer lane, guarantee the stability and the working effect of first tapered roller bearing installation.

In conclusion, the invention has the following beneficial effects:

1. the zero backlash is realized by arranging and meshing the bevel gears between the bevel cycloidal gear and the roller pin and between the bevel planetary gear and the input bevel gear, and arranging the output anti-backlash structure and the input anti-backlash structure at two ends of the eccentric shaft respectively, so that the backlash between the bevel cycloidal gear and the roller pin at the side of the position and the backlash between the bevel planetary gear at the input side and the input bevel gear can be eliminated;

2. the speed reducer cannot avoid abrasion after being used for a long time, and the abrasion can generate gaps among mechanical parts;

3. the transmission precision of the speed reducer depends on the dynamic meshing condition of the gear to a great extent, and the dynamic meshing condition of the gear cannot reach a theoretical state due to various factors in processing and assembling;

4. the vibration of the motion state of the speed reducer is caused by the inconsistent transmission state of the speed reducer, and the output anti-backlash structure and the input anti-backlash structure improve the meshing state between the bevel-tooth cycloidal gear and the roller pin and between the bevel-tooth planetary gear and the input bevel gear, so that the vibration of the speed reducer during the operation can be greatly reduced.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a zero backlash self-adjusting structure RV reducer;

FIG. 2 is an enlarged view of portion A of FIG. 1;

FIG. 3 is a schematic diagram of an overall structure of a zero backlash self-adjusting RV reducer for embodying the structure of balls in another embodiment;

fig. 4 is an enlarged view of a portion B in fig. 3.

In the figure, 1, a needle gear shell; 2. a conical semicircular groove; 3. rolling needles; 4. an output shaft; 5. an output end cover; 6. mounting a bearing; 7. a skeleton sealing ring; 8. an input shaft; 9. a first tapered roller bearing; 10. a clamp spring for the hole; 11. A limiting step; 12. an eccentric shaft; 13. a cage needle bearing; 14. a second cover; 15. a bevel-tooth cycloid wheel; 16. a double row tapered roller; 17. a bevel planet gear; 18. an input bevel gear; 19. outputting a gap eliminating structure; 20. a first cover; 21. a first butterfly-shaped elastic sheet; 22. a first cushion block; 221. a rolling groove; 222. a rolling ring groove; 23. a ball bearing; 24. inputting a gap eliminating structure; 25. a second cushion block; 26. a second butterfly-shaped elastic sheet; 27. a nut; 28. a retainer ring for a shaft.

Detailed Description

The present invention will be described in further detail with reference to the following drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

A zero-backlash self-adjusting structure RV reducer comprises a pin gear shell 1, an output shaft 4, an output end cover 5, an input shaft 8 and two or three (three in the embodiment) eccentric shafts 12 arranged in a circumferential array, wherein the output shaft 4 and the output end cover 5 are fixedly combined into an assembly coaxial with the pin gear shell 1 through screws and pins, and mounting bearings 6 are respectively arranged between the outer circle of the output shaft 4, the outer circle of the output end cover 5 and the inner circle of the pin gear shell 1, so that the assembly formed by the output shaft 4 and the output end cover 5 can rotate relative to the pin gear shell 1. The mounting bearing 6 is one of a tapered roller bearing, an angular contact ball bearing, or a deep groove ball bearing, and in this embodiment, the mounting bearing 6 is a tapered roller bearing. In addition, a skeleton sealing ring 7 is arranged between the output shaft 4 and the pin gear shell 1, and the skeleton sealing ring 7 is positioned on one side, far away from the output end cover 5, of the mounting bearing 6 close to the skeleton sealing ring 7, so that sealing between the output shaft 4 and the pin gear shell 1 is realized.

As shown in fig. 1, a plurality of circular holes matched with a plurality of eccentric shafts 12 are circumferentially arranged on the output shaft 4 and the output end cover 5 in an array manner, and two ends of the eccentric shafts 12 are respectively installed in the corresponding circular holes on the output shaft 4 and the output end cover 5 through retainer needle roller bearings 13, so that the eccentric shafts 12 and a combined member composed of the output shaft 4 and the output end cover 5 can rotate relatively and move axially in a small range. Wherein, the output end cover 5 is provided with a second sealing cover 14 matched with the eccentric shaft 12 and the retainer needle roller bearing 13, and the retainer needle roller bearing 13 and the eccentric shaft 12 are prevented from sliding out by the second sealing cover 14.

As shown in fig. 1, two bevel cycloid wheels 15 are respectively installed on the eccentric shaft 12 in a limiting manner, a plurality of conical semicircular grooves 2 are arranged on the circumferential array of the inner wall of the needle gear shell 1, two groups of conical semicircular grooves 2 are arranged and respectively correspond to the two bevel cycloid wheels 15, needle rollers 3 matched with the conical semicircular grooves 2 are assembled in the conical semicircular grooves 2, and a plurality of conical outer teeth meshed with the conical teeth of the needle rollers 3 are arranged on the circumferential array of the outer wall of the bevel cycloid wheel 15. The conical semicircular groove 2 has a certain taper, one end of the conical semicircular groove close to the output end cover 5 is of a small head structure, and similarly, the conical outer teeth on the outer wall of the conical tooth cycloid wheel 15 are also of a small head structure close to the output end cover 5.

As shown in fig. 1 and 2, an output anti-backlash structure 19 is provided at one end of the eccentric shaft 12 close to the output shaft 4, and the output anti-backlash structure 19 drives the eccentric shaft 12 to drive the whole bevel-tooth cycloidal gear 15 to deviate along the axial direction. In this embodiment, the output anti-backlash structure 19 includes a first sealing cover 20, a first butterfly spring 21, a first cushion block 22 and a ball 23, which are arranged in a circular hole of the output shaft 4 for mounting the eccentric shaft 12, wherein the ball 23 is in rolling fit with one end of the eccentric shaft 12 close to the output shaft 4, and the ball 23 is mounted on a side wall of the first cushion block 22 in a rolling manner; the first butterfly-shaped elastic sheet 21 is located on one side of the first cushion block 22 away from the ball 23, and the first cover 20 is located on one side of the first butterfly-shaped elastic sheet 21 away from the first cushion block 22.

As shown in fig. 1 and fig. 2, the first butterfly-shaped elastic sheet 21 is pre-pressed by a certain deformation amount through the locking seal cover, so that the balls 23 are pushed against the end portion of the eccentric shaft 12 by the first cushion block 22, and then the eccentric shaft 12 drives the bevel cycloidal gear 15 to synchronously move, so that the conical outer teeth of the bevel cycloidal gear 15 are tightly meshed with the needle rollers 3, and the meshing gap between the bevel cycloidal gear 15 and the needle rollers 3 is elastically eliminated. When the bevel cycloidal gear 15 and the roller pin 3 are abraded after long-time work, the first butterfly-shaped elastic sheet 21 drives the eccentric shaft 12 to drive the whole bevel cycloidal gear 15 to slightly move towards the side close to the output end cover 5, so that the conical outer teeth of the bevel cycloidal gear 15 are tightly meshed with the roller pin 3 all the time, and a gap is prevented from being generated between the bevel cycloidal gear 15 and the roller pin 3. And because the elasticity of first butterfly shell fragment 21 for bevel gear cycloid wheel 15 one side has certain deformability, when bevel gear cycloid wheel 15 and kingpin 3 meshing, can not appear because of errors such as processing and assembly the dead condition of card emergence in the meshing process.

The material, structure, pre-pressing deformation and the like of the first butterfly-shaped elastic sheet 21 can be selected according to the meshing force requirement of the bevel-tooth cycloidal gear 15 and the needle roller 3, the output torque on the output side and the like, and the taper range of the conical semi-circular groove 2 and the conical external teeth on the bevel-tooth cycloidal gear 15 is 1. In addition, in other embodiments, the first butterfly spring 21 may be replaced by a spring.

As shown in FIG. 1, each bevel cycloidal gear 15 is formed by two rows of tapered rollers 16 respectively mounted on two cams of the eccentric shaft 12, and the outer wall of the cam of the eccentric shaft 12 and the inner wall of the bevel cycloidal gear 15 are respectively used as the inner ring and the outer ring of the double rows of tapered rollers 16 for limiting installation. Therefore, under the limiting and fixing action of the outer wall of the cam of the eccentric shaft 12 and the inner wall of the bevel-tooth cycloidal gear 15, the bevel-tooth cycloidal gear 15 and the eccentric shaft 12 can only rotate relatively but cannot move axially, and the output anti-backlash structure 19 can drive the bevel-tooth cycloidal gear 15 to move synchronously by driving the eccentric shaft 12 to move, so that the gap between the bevel-tooth cycloidal gear 15 and the roller pin 3 is eliminated.

The reason why each bevel-tooth cycloid wheel 15 is mounted by using the double-row tapered rollers 16 is that the bevel-tooth cycloid wheel 15 is eccentrically meshed with the needle rollers 3, and the conical meshing causes the bevel-tooth cycloid wheel 15 to bear a unilateral axial force after a force is applied to a meshing side, and the non-meshing side cannot offset the axial force because of no meshing. Therefore, in order to counteract the axial force, the double-row tapered rollers 16 are arranged, one row is used for the eccentric shaft 12 to drive the bevel-tooth cycloidal gear 15 to move synchronously, so that the bevel-tooth cycloidal gear 15 can be tightly meshed with the needle rollers 3, and the other row is used for counteracting the unilateral stress of the bevel-tooth cycloidal gear 15, so that the instability of the whole structure is avoided.

As shown in fig. 1 and fig. 2, in the present embodiment, one ball 23 is provided and located on the axis of the eccentric shaft 12, and the first pad 22 is provided with a rolling groove 221 engaged with the ball 23. The rolling fit of the ball 23 and the eccentric shaft 12 is utilized to reduce the abrasion of the eccentric shaft 12 to the first butterfly-shaped elastic sheet 21 caused by high-speed rotation, and ensure the working effect and the service life of the first butterfly-shaped elastic sheet 21. In another embodiment, as shown in fig. 3 and 4, the balls 23 are arranged in a plurality of circumferential arrays around the axis of the eccentric shaft 12, the first spacer 22 is provided with a rolling ring groove 222 coaxial with the eccentric shaft 12, and the plurality of balls 23 are positioned and rolled in the rolling ring groove 222. The rolling contact points are increased by arranging the balls 23, the rolling friction effect of the eccentric shaft 12 on the balls 23 is dispersed, and the using effect and the service life of the balls 23 are improved. Of course, in order to avoid friction between adjacent balls 23, a retainer (not shown) engaged with the balls 23 may be provided in the rolling ring groove 222 to limit the balls 23, thereby further improving the service life of the balls 23.

As shown in fig. 1, both ends of the input shaft 8 are respectively installed in the central holes of the assembly composed of the output shaft 4 and the output end cover 5 through the first tapered roller bearings 9, the outer races of the two first tapered roller bearings 9 are respectively fixed in the central holes of the output main and output end covers 5 through the holes by the snap springs 10, and the two holes are located on the sides of the two first tapered roller bearings 9 away from each other by the snap springs 10. The outer wall of the input shaft 8 is provided with a limiting step 11, and the inner ring of the first tapered roller bearing 9 is clamped on the limiting step 11. Of course, in other embodiments, the input shaft 8 may not be fixed inside the speed reducer, but may be directly fixed to the motor.

As shown in fig. 1, a bevel gear planet wheel 17 is mounted on one end of the eccentric shaft 12 close to the output end cover 5 through a spline, an input bevel gear 18 is mounted on the end portion of the input shaft 8 through a spline, the input bevel gear 18 is meshed with the bevel gear planet wheel 17 through a bevel gear, one side of the bevel gear of the outer wall of the bevel gear planet wheel 17 close to the bevel gear cycloid wheel 15 is of a small head structure, and one side of the input bevel gear 18 close to the bevel gear cycloid wheel 15 is of a large head structure. The second cushion block 25 is sleeved on the input shaft 8, and the second cushion block 25 is positioned between the input bevel gear 18 and the inner ring of the first tapered roller bearing 9 close to the input bevel gear.

As shown in fig. 1, an input anti-backlash structure 24 is arranged at one end of the eccentric shaft 12 close to the output end cover 5, and the input anti-backlash structure 24 drives the bevel planet gears 17 to deviate along the axis thereof relative to the eccentric shaft 12. In this embodiment, the input anti-backlash structure 24 includes a second butterfly-shaped elastic piece 26 disposed on one side of the bevel-tooth planet wheel 17 away from the bevel-tooth cycloidal gear 15, a nut 27 for locking the second butterfly-shaped elastic piece 26 on the eccentric shaft 12 is disposed on one side of the second butterfly-shaped elastic piece 26 away from the bevel-tooth planet wheel 17, and an axial retaining ring 28 is disposed on one side of the bevel-tooth planet wheel 17 away from the second butterfly-shaped elastic piece 26.

As shown in fig. 1, the second butterfly spring 26 is pre-compressed by a certain amount by adjusting the nut 27, and a certain force is applied to the bevel gear 17 along the axial direction thereof, so that the bevel gear 17 is tightly engaged with the input bevel gear 18, thereby eliminating the backlash therebetween. When the bevel gear planet wheel 17 and the input bevel gear 18 are worn after long-time operation, the bevel gear planet wheel 17 is driven to move slightly towards the direction close to the bevel gear cycloid wheel 15 under the action of the elastic force of the second butterfly-shaped elastic sheet 26, and a gap is prevented from being generated between the bevel gear cycloid wheel 15 and the input bevel gear 18. And because the elasticity of second butterfly-shaped shell fragment 26 for bevel gear planet wheel 17 has certain deformability, when bevel gear planet wheel 17 and input bevel gear 18 meshing, can not appear because of errors such as processing and assembly the meshing in-process and take place the card dead condition.

The material, structure, pre-pressing deformation and the like of the second butterfly-shaped elastic sheet 26 can be selected according to the meshing force requirement, rated torque and the like of the bevel gear planet gear 17 and the input bevel gear 18, and the taper range of the tapered external teeth of the bevel gear planet gear 17 and the input bevel gear 18 is 1-1. In addition, the second butterfly spring 26 can be replaced by a spring in other embodiments.

The working principle and the using method of the invention are as follows:

gap elimination at the output side:the first butterfly-shaped elastic sheet 21 is pre-pressed by a locking seal cover for a certain deformation amount, so that the first cushion block 22 props the ball 23 against the end part of the eccentric shaft 12, the eccentric shaft 12 drives the bevel cycloidal gear 15 to synchronously move, the conical outer teeth of the bevel cycloidal gear 15 are tightly meshed with the roller pin 3, and the meshing between the bevel cycloidal gear 15 and the roller pin 3 is elastically eliminatedAnd (4) clearance. When the bevel cycloidal gear 15 and the roller pins 3 are worn after long-time operation, the first butterfly-shaped elastic sheet 21 drives the eccentric shaft 12 to drive the whole bevel cycloidal gear 15 to slightly move towards the side close to the output end cover 5, so that the conical outer teeth of the bevel cycloidal gear 15 are tightly meshed with the roller pins 3 all the time, and a gap is prevented from being generated between the bevel cycloidal gear 15 and the roller pins 3.

Input side gap elimination:the second butterfly spring 26 is pre-compressed by a certain amount by adjusting the nut 27, and a certain force along the axial direction of the bevel gear planet wheel 17 is applied, so that the bevel gear planet wheel 17 is tightly meshed with the input bevel gear 18, and the backlash between the two is eliminated. When the bevel gear planet wheel 17 and the input bevel gear 18 are worn after long-time work, the bevel gear planet wheel 17 is driven to move slightly towards the direction close to the bevel gear cycloid wheel 15 under the action of the elastic force of the second butterfly-shaped elastic sheet 26, and a gap is prevented from being generated between the bevel gear cycloid wheel 15 and the input bevel gear 18.

High life:the speed reducer can not avoid abrasion after being used for a long time, and the abrasion can generate gaps among mechanical parts.

High precision:because of the elasticity of the first butterfly-shaped elastic sheet 21 and the second butterfly-shaped elastic sheet 26, one side of the bevel-tooth cycloidal gear 15 close to the output anti-backlash structure 19 and one side of the bevel-tooth planetary gear 17 close to the input anti-backlash structure 24 have certain yielding capacity, when the bevel-tooth cycloidal gear 15 is meshed with the roller pin 3 and the bevel-tooth planetary gear 17 is meshed with the input bevel gear 18, the situation of clamping in the meshing process due to errors such as machining and assembling can be avoided, the meshing error caused by the factors such as machining and assembling can be reduced, and the transmission precision can be improved.

Low vibration:the vibration of the motion state of the speed reducer is caused by the inconsistent transmission state of the speed reducer, the output anti-backlash structure 19 and the input anti-backlash structure 24 improve the meshing state between the bevel-tooth cycloidal gear 15 and the needle roller 3 and between the bevel-tooth planetary gear 17 and the input bevel gear 18, and can greatly reduce the vibration of the speed reducer during the operationThe vibration of (2).

While the foregoing description shows and describes the preferred embodiments of the present invention, it is to be understood that the invention is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as described herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The utility model provides a zero backlash is from regulation structure RV speed reducer which characterized in that: the bevel gear transmission mechanism comprises a needle gear shell (1), an output shaft (4), an output end cover (5), an input shaft (8) and at least two eccentric shafts (12) arranged in a circumferential array, wherein bevel-gear cycloidal gears (15) are respectively installed on two eccentric cams of the eccentric shafts (12) in a limiting manner, one ends of the eccentric shafts (12) close to the output end cover (5) are provided with bevel-gear planet wheels (17), the end part of the input shaft (8) is provided with an input bevel gear (18), and the input bevel gear (18) is meshed with the bevel-gear planet wheels (17) in a bevel gear manner; the needle gear shell is characterized in that a plurality of conical semicircular grooves (2) are formed in the circumferential array of the inner wall of the needle gear shell (1), roller pins (3) matched with the conical semicircular grooves (2) are assembled in the conical semicircular grooves (2), and a plurality of conical outer teeth meshed with conical teeth of the roller pins (3) are formed in the circumferential array of the outer wall of the conical cycloid gear (15); an output anti-backlash structure (19) is arranged at one end, close to the output shaft (4), of the eccentric shaft (12), and the output anti-backlash structure (19) drives the eccentric shaft (12) to drive the whole bevel-tooth cycloidal gear (15) to axially deviate; an input anti-backlash structure (24) is arranged at one end, close to the output end cover (5), of the eccentric shaft (12), and the input anti-backlash structure (24) drives the bevel gear planet wheel (17) to deviate relative to the eccentric shaft (12) along the axis of the bevel gear planet wheel.

2. The zero backlash self-adjusting structure RV speed reducer of claim 1, characterized in that: the output anti-backlash structure (19) comprises a first sealing cover (20) arranged on the output shaft (4), the first sealing cover (20) is positioned in a round hole of the output shaft (4) for mounting the eccentric shaft (12), and a first butterfly-shaped elastic sheet (21) matched with the end part of the eccentric shaft (12) is arranged on one side, close to the eccentric shaft (12), of the first sealing cover (20).

3. The zero backlash self-adjusting structure RV speed reducer of claim 2, characterized in that: one side of the first butterfly-shaped elastic sheet (21) far away from the first sealing cover (20) is provided with a first cushion block (22), one side of the first cushion block (22) far away from the first butterfly-shaped elastic sheet (21) is provided with a ball (23), and the ball (23) is in rolling fit with the end part of the eccentric shaft (12).

4. The zero backlash self-adjusting structure RV speed reducer of claim 3, characterized in that: one side of the first cushion block (22) far away from the first butterfly-shaped elastic sheet (21) is provided with a rolling ring groove (222) coaxial with the eccentric shaft (12), and the balls (23) are arranged in the rolling ring groove (222) in a circumferential array along the rolling ring groove (222) and are all positioned and rolled and installed in the rolling ring groove (222).

5. The zero backlash self-adjusting structure RV reducer of claim 3 or 4, characterized in that: the locking and pre-pressing device is characterized in that a first sealing cover (20) locks and pre-presses a first butterfly-shaped elastic sheet (21), the first butterfly-shaped elastic sheet (21) props against the end part of an eccentric shaft (12) through a first cushion block (22) and balls (23), the eccentric shaft (12) drives a bevel-tooth cycloidal gear (15) to move synchronously, conical outer teeth of the bevel-tooth cycloidal gear (15) are tightly meshed with roller pins (3), and a tooth gap between the bevel-tooth cycloidal gear (15) and the roller pins (3) is eliminated elastically.

6. The zero backlash self-adjusting structure RV speed reducer of claim 1, characterized in that: the bevel gear planet wheel (17) is arranged at one end of the eccentric shaft (12) through a spline, the input bevel gear (18) is arranged on the input shaft (8) through a spline, and a second cushion block (25) is arranged on one side, close to the output end cover (5), of the input bevel gear (18); the input anti-backlash structure (24) comprises a second butterfly-shaped elastic sheet (26) arranged on one side, away from the bevel-tooth cycloid wheel (15), of the bevel-tooth planet wheel (17), a nut (27) used for locking the second butterfly-shaped elastic sheet (26) on the eccentric shaft (12) is arranged on one side, away from the bevel-tooth planet wheel (17), of the second butterfly-shaped elastic sheet (26), and a shaft check ring (28) is arranged on one side, away from the second butterfly-shaped elastic sheet (26), of the bevel-tooth planet wheel (17).

7. The zero backlash self-adjusting structure RV speed reducer of claim 6, characterized in that: the nut (27) is used for locking and pre-pressing the second butterfly-shaped elastic sheet (26), the outer teeth of the bevel gear planet wheels (17) are tightly meshed with the outer teeth of the input bevel gears (18) under the elastic action of the second butterfly-shaped elastic sheet (26), and the backlash between the bevel gear planet wheels (17) and the input bevel gears (18) is eliminated elastically.

8. The zero backlash self-adjusting structure RV speed reducer of claim 1, characterized in that: mounting bearings (6) are respectively arranged between the outer circle of the output shaft (4), the outer circle of the output end cover (5) and the inner circle of the needle gear shell (1), and the mounting bearings (6) are one of tapered roller bearings, angular contact ball bearings or deep groove ball bearings; be equipped with skeleton sealing washer (7) between output shaft (4) and pin wheel housing (1), just skeleton sealing washer (7) are located rather than the installation bearing (6) that is close to one side of keeping away from output end cover (5).

9. The zero-backlash self-adjusting structure RV reducer as claimed in claim 1, wherein: each bevel cycloid wheel (15) is installed on a corresponding cam on the eccentric shaft (12) through a plurality of double-row tapered rollers (16) arranged in a circumferential array, and the outer wall of the cam of the eccentric shaft (12) and the inner wall of the bevel cycloid wheel (15) are respectively used as an inner ring and an outer ring of the double-row tapered rollers (16) for limiting installation.

10. The zero-backlash self-adjusting structure RV reducer as claimed in claim 1, wherein: two ends of the input shaft (8) are respectively installed on the output shaft (4) and the output end cover (5) through first tapered roller bearings (9), outer rings of the two first tapered roller bearings (9) are respectively fixed through holes by using clamp springs (10), and the two holes are located on one sides, away from each other, of the two first tapered roller bearings (9) by using the clamp springs (10); the outer wall of the input shaft (8) is provided with a limiting step (11), and the inner ring of the first tapered roller bearing (9) is clamped on the limiting step (11).