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CN-122014835-A - Radial pre-tightening cycloid reducer for robot joint

CN122014835ACN 122014835 ACN122014835 ACN 122014835ACN-122014835-A

Abstract

The invention discloses a radial pre-tightening cycloidal reducer of a robot joint, which comprises a shell, a flange assembly, an input shaft with double eccentric sleeves, cycloidal gears, needle teeth, a radial deformable needle wheel and a radial pre-tightening assembly, wherein the flange assembly is arranged in the shell, the radial pre-tightening assembly is tightly sleeved on the outer contour surface of the radial deformable needle wheel and continuously applies radial pre-tightening force to the outer contour surface, and when a wear gap occurs between the needle teeth and the cycloidal gears, the radial pre-tightening assembly drives the inner contour surface to press the radial deformable needle wheel, so that the radial deformable needle wheel is close to the outer contour surface of the cycloidal gears and radially and inwards generates elastic contraction to drive the needle teeth to radially move towards the cycloidal gears, so that the wear gap is eliminated. The self-adaptive dynamic compensation of the wear gap is realized by installing the two ends of the pin teeth between the pin wheels capable of being deformed in the radial direction and sleeving the radial pre-tightening components which continuously exert pre-tightening force on the outer contour surface of the pin teeth, so that the transmission precision holding capacity of the speed reducer in the whole life cycle is improved.

Inventors

  • CHEN ZHIHE
  • HU QIUSHI
  • ZHAO KELONG
  • ZHANG HAOFEI
  • DANG JING

Assignees

  • 江苏科技大学

Dates

Publication Date
20260512
Application Date
20260317

Claims (10)

  1. 1. The radial pre-tightening cycloidal reducer of the robot joint is characterized by comprising a shell (1), a flange component (2) arranged in the shell (1), an input shaft (3) with a double eccentric sleeve, a cycloidal gear (4), needle teeth (5), a radial deformable needle wheel (6) and a radial pre-tightening component (7); Two groups of radially deformable needle wheels (6) are oppositely arranged along the axial direction, two ends of each needle tooth (5) are respectively connected with opposite surfaces of the two radially deformable needle wheels (6), and the radially deformable needle wheels (6) are detachably connected with the inner side surface of the shell (1) along the outer contour surface away from the cycloidal gear (4) along the axial direction; The double eccentric sleeve of the input shaft (3) is sleeved with two roller bearings (8), the cycloidal gear (4) is sleeved on the roller bearings (8) and arranged between the two radially deformable pin gears (6), the tooth profile of the cycloidal gear (4) is meshed with the pin teeth (5) on the radially deformable pin gears (6), and the flange assembly (2) is sleeved on the input shaft (3) and detachably connected with the cycloidal gear (4); The radial pre-tightening assembly (7) is tightly sleeved on the outer contour surface of the radially deformable pin wheel (6) and continuously applies radial pre-tightening force to the pin wheel, when a wear gap occurs between the pin teeth (5) and the cycloid wheel (4), the radial pre-tightening assembly (7) drives the inner contour surface of the pin teeth to press the radially deformable pin wheel (6), so that the radially deformable pin wheel (6) is close to the outer contour surface of the cycloid wheel (4) to radially and inwards generate elastic shrinkage, and the pin teeth (5) are driven to radially move towards the cycloid wheel (4) so as to eliminate the wear gap.
  2. 2. The radial pre-tightening cycloidal reducer of the robot joint according to claim 1, further comprising deformation grooves (61) distributed and formed in the radial deformable pin wheel (6) along the circumferential direction, wherein the deformation grooves (61) are formed in the direction away from the cycloidal wheel (4) from the end surface of the radial deformable pin wheel (6), and the number of the deformation grooves (61) is the same as that of the pin teeth (5).
  3. 3. The radial pre-tightening cycloidal reducer of the robot joint according to claim 1 or 2, wherein the radial pre-tightening assembly (7) comprises a pre-tightening part (71) and two groups of pre-tightening sleeves (72) which are respectively and tightly sleeved on the outer contour surfaces of the two groups of radially deformable needle wheels (6) and are oppositely arranged, and two ends of the pre-tightening part (71) are respectively and movably connected with the opposite surfaces of the two pre-tightening sleeves (72).
  4. 4. The radial pre-tightening cycloidal reducer for the robot joint according to claim 3, wherein the pre-tightening part (71) comprises a pre-tightening pin (711) and a compression spring (712) sleeved on the pre-tightening pin (711), two ends of the pre-tightening pin (711) are respectively movably connected with opposite surfaces of the two pre-tightening sleeves (72), and two ends of the compression spring (712) are abutted with the opposite surfaces of the two pre-tightening sleeves (72).
  5. 5. The radial pre-tightening cycloidal reducer of the robot joint according to claim 4, wherein the opposite surfaces of the two pre-tightening sleeves (72) are respectively provided with corresponding pre-tightening pin holes (721), two ends of the pre-tightening pin (711) are respectively inserted into the pre-tightening pin holes (721) of the two pre-tightening sleeves (72), and the compression spring (712) drives the two pre-tightening sleeves (72) to move in the opposite directions along the axial directions of the pre-tightening pin holes (721).
  6. 6. The radial pre-tightening cycloidal reducer of the robot joint according to claim 3, wherein the inner contour surface of the pre-tightening sleeve (72) is a conical inner contour surface, the outer contour surface of the radially deformable pin wheel (6) axially approaching the cycloidal gear (4) is a conical outer contour surface, the conical inner contour surface and the conical outer contour surface are tightly attached, and the small ends of the conical inner contour surface and the conical outer contour surface face towards the cycloidal gear (4).
  7. 7. The robot joint radial pre-tightening cycloidal reducer according to claim 6, characterized in that the conical outer contour surface of the radially deformable pin wheel (6) comprises, in an axial section, a continuous contour line of a first outer cone segment AB, a first outer transition segment BC, a second outer transition segment CD, a second outer cone segment DE, the inclination angle θ 2 of the second outer cone segment DE being larger than the inclination angle θ 1 of the first outer cone segment AB.
  8. 8. The radial pre-tightening cycloidal reducer of a robot joint according to claim 7, characterized in that the conical inner contour surface of the pre-tightening sleeve (72) comprises a continuous contour line in an axial section, wherein the first inner cone section A 'B', the first inner transition section B 'C', the second inner transition section C 'D', the second inner cone section D 'E', the first inner cone section A 'B' and the first outer cone section AB have the same slope, and the second inner cone section D 'E' and the second outer cone section DE have the same slope.
  9. 9. The robot joint radial pretension cycloidal reducer according to claim 8, wherein the first outer transition section BC and the second outer transition section CD are perpendicular to each other and the first inner transition section B 'C' and the second inner transition section C 'D' are perpendicular to each other in an axial section.
  10. 10. The radial pre-tightening cycloidal reducer of the robot joint according to claim 1, wherein the flange assembly (2) comprises an input end flange (21), a connecting end flange (22) and an output end flange (23) which are sleeved on the input shaft (3), the input end flange (21) and the connecting end flange (22) are respectively arranged on two sides of the cycloidal gear (4) and detachably connected with the cycloidal gear (4), and the output end flange (23) is connected with the connecting end flange (22).

Description

Radial pre-tightening cycloid reducer for robot joint Technical Field The invention relates to a radial pre-tightening cycloidal reducer for a robot joint, and belongs to the technical field of reducers. Background The cycloidal reducer realizes differential gear transmission by utilizing eccentric motion formed between the cycloidal gear and the needle gear, and has the characteristics of large reduction ratio and high transmission precision. Along with the development of humanoid robot technology, cycloid speed reducers are increasingly widely applied to key parts of humanoid robots such as lower limb joints, waist hip joints, shoulder joints and the like, and higher requirements are also provided for the initial precision of the speed reducers and the precision holding capacity of the speed reducers in the long-term service process. However, during long-term operation, the cycloidal gear inevitably wears with the pin teeth due to the influence of external factors such as operating load and impact, and the inherent eccentric motion characteristic between the cycloidal gear and the pin gear. With the extension of the service time, the fit clearance between the cycloidal gear and the pin gear is gradually increased, so that the transmission precision of the cycloidal reducer is continuously reduced, and finally, the requirement of a high-precision application scene is difficult to meet. Disclosure of Invention Aiming at the defects in the prior art, the invention provides the radial pre-tightening cycloidal reducer for the robot joint, which drives the radial deformable pin wheel to elastically shrink through the radial pre-tightening assembly, dynamically compensates the abrasion gap and keeps long-term transmission precision. The technical scheme is that the radial pre-tightening cycloidal reducer of the robot joint comprises a shell, a flange assembly, an input shaft with a double eccentric sleeve, a cycloidal gear, pin teeth, a radial deformable pin wheel and a radial pre-tightening assembly, wherein the flange assembly is arranged in the shell; The two ends of the pin teeth are respectively connected with the opposite surfaces of the two radial deformable pin wheels, and the radial deformable pin wheels are detachably connected with the inner side surface of the shell along the outer contour surface which is axially far away from the cycloidal gear; The double eccentric sleeve of the input shaft is sleeved with two roller bearings, the cycloid gear is sleeved on the roller bearings and arranged between the two radially deformable pin gears, the tooth profile of the cycloid gear is meshed with the pin teeth on the radially deformable pin gears, and the flange assembly is sleeved on the input shaft and detachably connected with the cycloid gear; The radial pre-tightening assembly is tightly sleeved on the outer contour surface of the radially deformable pin wheel and continuously applies radial pre-tightening force to the pin wheel, and when a wear gap occurs between the pin teeth and the cycloidal wheel, the radial pre-tightening assembly drives the inner contour surface of the pin wheel to press the radially deformable pin wheel, so that the radially deformable pin wheel is close to the outer contour surface of the cycloidal wheel and elastically contracts inwards in the radial direction to drive the pin teeth to radially move towards the cycloidal wheel, and the wear gap is eliminated. According to the invention, the two ends of the needle teeth are arranged between the radially deformable needle wheels, and the radially pre-tightening assembly is sleeved on the outer contour surface of the needle teeth, when the needle teeth and the cycloidal wheels are in clearance due to long-term service wear, the radially pre-tightening assembly continuously applies pre-tightening force to press the radially deformable needle wheels to keep an elastic compression state which is contracted radially inwards all the time, so that the needle teeth are driven to move radially towards the cycloidal gear tooth profile direction, the dynamic backlash-free meshing of the needle teeth and the cycloidal wheels is realized, the technical problems that the transmission precision is continuously reduced and the high-precision application requirement cannot be met due to wear after the existing cycloidal speed reducer is used for a long time are solved, and the precision holding capacity of the speed reducer in a whole life cycle is improved. The preference is in order to ensure that radial deformation pinwheel can produce stable, even radial contraction under radial pretension subassembly's the oppression that lasts, avoids local stress concentration to lead to deformation inequality, still includes along the circumferencial direction distribution and sets up the deformation groove on radial deformation pinwheel, the deformation groove is offered from the terminal surface of radial deformation pinwheel to the direction of keep