High-rigidity harmonic speed reducer

Abstract

The utility model provides a high-rigidity harmonic speed reducer, which relates to the technical field of speed reducers and comprises a novel rear cover, a novel flexible gear, a novel cross roller bearing, a novel rigid gear, a novel front cover, a novel flexible bearing, a novel front support bearing, a novel rear support bearing and a novel wave generator. The novel cross roller bearing comprises two rows of rollers arranged in parallel, the novel flexible gear comprises a thin-walled cylinder, an extension flange and a step ring, and the end, close to the novel rear cover, of the extension flange is flush with the end, close to the novel rear cover, of the step ring. An outer ring step is arranged at one end, close to the step ring, of the bearing outer ring; the outer circle of the outer ring step and the inner circle of the step ring are contacted, matched and positioned; the ratio of the axial length of the thin-walled cylinder to the diameter of an inner hole of the thin-walled cylinder is 0.35-0.7, the diameter of the inner hole of the thin-walled cylinder is 0.5-0.7 times of the maximum outer diameter of the novel rear cover, the novel flexible gear and the novel cross roller bearing, and the ratio of the width of the upper teeth of the thin-walled cylinder to the axial length of the thin-walled cylinder is 0.3-0.5. According to the utility model, by optimizing the internal structure and the size, the impact resistance and the torque are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of reducers, in particular to a high-rigidity harmonic reducer. Background Art

[0002] The harmonic reducer is a flexible reducer that relies on the deformation of the flexible wheel for transmission. It has excellent tooth clearance, transmission accuracy, noise and vibration performance, but its impact and torque resistance are weak. Figure 1 This is a simplified structural diagram of a traditional harmonic reducer, which mainly includes the rear cover 01, flexible wheel 02, cross roller bearing 03, rigid wheel 04, front cover 05, flexible bearing 06, deep groove ball bearing 07, skeleton sealing ring 08, wave generator 09 and other parts.

[0003] When the harmonic reducer is used in the field of high-speed operation, it requires a larger start-stop torque and impact torque at high speed; when it is used in the field of normal speed, it is also easy to cause flexible bearing failure, deep groove ball bearing failure, flexible wheel rigid wheel tooth damage, etc. due to its weak impact resistance; when it is used in the field of carrying large loads, the cross roller bearing has weak torque performance and needs to add additional larger support bearings to compensate. When traditional harmonic reducers are used in industrial robots, the above problems are particularly prominent. Therefore, it is necessary to design a high-rigidity harmonic reducer that can improve the torque and moment of the harmonic reducer while keeping the overall axial length and radial width of the harmonic reducer unchanged, so as to meet the use requirements of more high-speed and high-load conditions. Utility Model Content

[0004] The purpose of the utility model is to provide a high-rigidity harmonic reducer. Under the condition that the overall axial length and radial width of the harmonic reducer remain unchanged, the impact resistance is greatly improved by lengthening the axial length of the flexible wheel, increasing the inner hole diameter, increasing the tooth width, increasing the tooth width of the rigid wheel, and increasing the size and number of flexible bearings through structural optimization. By lengthening the axial length of the cross-roller bearing, increasing the number of roller rows, and lengthening the axial spacing between rollers through structural improvements, a high-torque bearing is obtained, so that the harmonic reducer obtains high torque and high moment, and meets the use requirements under more high-speed and high-load conditions.

[0005] The above technical objectives of the utility model are achieved through the following technical solutions:

[0006] A high-rigidity harmonic reducer, comprising a new rear cover, a new flexible wheel, a new cross roller bearing, a new rigid wheel, a new front cover, a new flexible bearing, a new front support bearing, a new rear support bearing, and a new wave generator; the new cross roller bearing comprises a bearing outer ring and a bearing inner ring, two rows of rollers are arranged in parallel between the bearing outer ring and the bearing inner ring along their axial direction, and an O-type sealing ring is arranged between one end of the bearing outer ring away from the new rear cover and the step surface of the bearing inner ring;

[0007] The novel flexible wheel comprises a coaxially arranged and integrally formed thin-walled cylinder, an outer flange and a step ring, wherein the outer flange is arranged at one end of the thin-walled cylinder close to the novel rear cover and is located between the outer ring of the thin-walled cylinder and the inner ring of the step ring; the thickness of the outer flange is less than the thickness of the step ring, and the end of the outer flange close to the novel rear cover is flush with the end of the step ring close to the novel rear cover; the end of the outer ring of the bearing close to the step ring is provided with an outer ring step, and the outer circle of the outer ring step is contacted and matched with the inner circle of the step ring for positioning;

[0008] The ratio of the axial length of the thin-walled tube to its inner hole diameter is between 0.35-0.7, and the inner hole diameter of the thin-walled tube is 0.5-0.7 times the largest outer diameter of the new rear cover, the new flexible wheel, and the new cross roller bearing; the outer wall of one end of the thin-walled tube close to the new front cover is meshed with the inner ring teeth of the new rigid wheel, and the tooth widths are matched, and the ratio of the tooth width on the thin-walled tube to the axial length of the thin-walled tube is between 0.3-0.5;

[0009] The new flexible spline tooth portion is provided with a lubricating oil groove, which is located in the middle of the tooth portion and is an annular groove arranged around the circumference of the new flexible spline, or the lubricating oil groove is a spiral groove arranged around the outer circumference of the new flexible spline tooth portion;

[0010] The new front cover is installed in plane contact with the new rigid wheel, the new rear cover is installed in plane contact with the step ring, and a clearance step is provided at a position corresponding to the outer flange on the inner side of the new rear cover to form a gap between the inner side and the outer flange.

[0011] By adopting the above technical solution, the traditional axial flat cross roller bearing is improved into a new cross roller bearing including two rows of rollers arranged in parallel, and the original skeleton seal ring is replaced by an O-ring. The outer diameter of the new cross roller bearing remains unchanged, and the inner diameter becomes larger, so as to achieve radial flatness. The larger the axial spacing between the two rows of rollers in the new cross roller, the greater the torque obtained. The inner hole of the new cross roller bearing becomes larger, so that the inner hole diameter of the new flexible wheel can be larger, and the inner hole diameter of the thin-walled tube can be increased to 1.09-1.35 times the inner hole diameter of the flexible wheel. At the same time, the diameter of the tooth part of the thin-walled tube becomes larger, and the outer diameter of the new flexible bearing increases synchronously, which greatly increases the torsional stiffness.

[0012] The thickest axial part of the traditional flexible wheel is a stepped structure, and the step does not contact the cross roller bearing. The extended flange in the new flexible wheel moves back to the end close to the new rear cover and is flush with the end of the step ring close to the new rear cover. The outer circle of the outer ring step on the outer ring of the bearing and the inner circle of the step ring in the new flexible wheel are in contact and positioned, making the axial length of the thin-walled tube longer, and the ratio of the axial length of the thin-walled tube to its inner hole diameter is between 0.35-0.7, obtaining greater flexibility, and the open inner hole of the thin-walled tube is stretched to a larger range.

[0013] The lengthening of the axial length of the thin-walled cylinder of the new flexible wheel further thickens the axial length of the new cross roller bearing, making it easier to install two rows of rollers. At the same time, the tooth width of the new flexible wheel is further widened, and the ratio of the tooth width on the thin-walled cylinder to the axial length of the thin-walled cylinder is between 0.3-0.5.

[0014] When the lubricating oil groove on the new flexible wheel gear is located in the middle and is a circumferential annular groove, the deformation ability of the tooth part close to the new front cover side under the action of the new rigid wheel is further obtained, while protecting the meshing of the tooth part close to the new rear cover side with the new rigid wheel, and the lubricating oil groove can store a certain amount of grease to ensure that the tooth part is more fully lubricated and has a longer life. When the lubricating oil groove is a spiral groove, it can not only lubricate the entire tooth part, but also make the new flexible wheel more improved in deformation, and the meshing area is increased while the stability is increased.

[0015] As the diameter of the inner hole of the new flexible wheel increases and the axial length of the thin-walled tube increases, the new flexible bearing can be enlarged, the load capacity is greatly improved, and the inner hole of the new flexible wheel tooth is supported by the outer ring of the new flexible bearing. The rigidity is also greatly improved. Similarly, the inner hole diameter of the new flexible bearing increases with the inner hole diameter of the new flexible wheel, so that the elliptical major axis and minor axis used to install the new flexible bearing on the new wave generator also increase, that is, the inner hole of the new wave generator is enlarged, and a large-aperture harmonic reducer is obtained. At the same time, the inner diameters of the new front support bearing and the new rear support bearing are increased synchronously to obtain a greater load capacity, which not only supports the smooth rotation of the new wave generator, but also enhances the anti-axial capacity.

[0016] The tooth width of the tooth portion on the new rigid wheel increases with the tooth width of the tooth portion on the thin-walled cylinder. The side of the new rigid wheel close to the new front cover is in direct planar contact with the new front cover, eliminating the positioning hole connection between the traditional front cover and the rigid wheel. The new front cover and the new rigid wheel are connected by hexagon socket flat round head screws. The thickness of the new front cover can be thinned to the point where the screws do not protrude from the plane when installed, thereby increasing the axial thickness of the side of the new rigid wheel close to the new front cover, which can correspondingly meet the further extension of the tooth width of the tooth portion of the thin-walled cylinder.

[0017] The new rear cover is installed in contact with the new rear cover and the step ring plane, and the original rear cover and flexible wheel and cross roller bearing positioning hole installation are cancelled. The new rear cover and the step ring and the outer ring of the bearing are fastened with hexagonal flat round head screws. The new rear cover can be thinned until the screws do not protrude from the surface, further providing space for the extension of the axial length of the thin-walled tube and the new cross roller bearing. A clearance step is provided at the corresponding position of the inner side of the new rear cover and the outer flange to form a gap between it and the outer flange to prevent the deformation of the thin-walled tube and the interference of the new rear cover.

[0018] Under the condition that the overall axial length and radial width of the harmonic reducer remain unchanged, the utility model greatly improves the impact resistance by lengthening the axial length of the flexible wheel, increasing the inner hole diameter, increasing the tooth width, increasing the tooth width of the rigid wheel, and enlarging the flexible bearing. By lengthening the axial length of the cross roller bearing, increasing the number of roller rows, and lengthening the axial spacing between rollers, a high-torque bearing is obtained, so that the harmonic reducer obtains high torque and high moment to meet the use requirements under more high-speed and high-load conditions. At the same time, because the structure of the harmonic reducer in the utility model is more compact, the internal space is further filled, the amount of grease added to the invalid parts is reduced, and the overall amount of grease added is reduced, thereby reducing the risk of grease leakage.

[0019] Furthermore, the novel flexible bearing is provided with and includes a single row of steel balls.

[0020] By adopting the above technical solution, since the inner hole diameter of the new flexible wheel becomes larger and the axial length of the thin-walled tube increases, there is space to install a new flexible bearing of larger size, and it matches the tooth width of the new flexible wheel and the tooth width of the new rigid wheel, so that the new flexible bearing is not only greatly improved in pitch circle diameter, steel ball diameter and total number of steel balls, but also the width of the outer ring of the new flexible bearing in contact with the inner hole of the new flexible wheel is increased synchronously, the load capacity of the new flexible bearing is greatly improved, and the rigidity of the inner hole of the new flexible wheel gear part supported by the outer ring of the new flexible bearing is also greatly improved.

[0021] Furthermore, the novel flexible bearing is provided with and includes two rows of steel balls arranged in parallel along its axial direction.

[0022] By adopting the above technical solution, the new flexible bearing is single and contains two rows of steel balls, which greatly improves the impact resistance and lateral swing resistance of the new flexible bearing, and the single new flexible bearing is easy to install.

[0023] Furthermore, two novel flexible bearings are arranged in parallel along the axial direction thereof, and each novel flexible bearing comprises a single row of steel balls.

[0024] By adopting the above technical solution, two new flexible bearings with single-row steel balls are arranged in parallel, which can greatly improve the impact resistance. The new flexible bearings with single-row steel balls are easy to obtain and have stronger flexibility.

[0025] Furthermore, the new front support bearing and the new rear support bearing are both deep groove ball bearings, the new rear support bearing is provided with one or two are provided in parallel along its axial direction, and an elastic retaining ring for the hole is provided between its outer ring and the new rear cover, and an elastic retaining ring for the shaft is provided between its inner ring and the new wave generator.

[0026] By adopting the above technical solution, the meshing force of the new rigid wheel and the new flexible wheel is transmitted to the new wave generator through the new flexible wheel and the new flexible bearing, and then transmitted to the new rear support bearing by the new wave generator, and a larger or two smaller new rear support bearings installed side by side are set to resist the axial force of the new wave generator. Among them, the new rear support bearing is a deep groove ball bearing, and the new rear support bearing is fixed by using elastic retaining rings for holes and elastic retaining rings for shafts to prevent it from axial movement. Among them, the axial force has a weak effect on the change of the axial position of the elastic retaining ring for the shaft, which is generally used for harmonic reducers with larger torque.

[0027] Furthermore, the new front support bearing and the new rear support bearing are both deep groove ball bearings, the new rear support bearing is provided with one or two are provided in parallel along its axial direction, and a wave ring is provided on the side close to the new rear cover and between the new rear cover.

[0028] By adopting the above technical solution, a larger or two smaller new rear support bearings installed side by side are set to resist the axial force of the new wave generator. Among them, the new rear support bearing is a deep groove ball bearing, and the new rear support bearing is fixed by a wave ring to prevent it from axial movement. Compared with the combination of elastic retaining rings for holes and elastic retaining rings for shafts, the influence on the size of the new rear support bearing is reduced. Among them, the axial force has a greater influence on the change of the axial position of the wave ring, which is generally used for harmonic reducers with small torque.

[0029] Furthermore, the new front support bearing and the new rear support bearing are both deep groove ball bearings, the new rear support bearing is provided with an axial thrust bearing parallel to the new rear cover on the side away from the new rear cover, and a thrust bearing gasket is provided between the axial thrust bearing and the new rear cover.

[0030] By adopting the above technical solution, an axial thrust bearing is set to mainly bear the axial force of the new wave generator, and the new rear support bearing and the axial thrust bearing jointly support the rotation and stability of the new wave generator. In this way, not only a greater axial load capacity can be obtained, but also the volume of the new rear support bearing can be greatly reduced, heat generation can be reduced, and accuracy can be improved.

[0031] Furthermore, the novel front support bearing and the novel rear support bearing are both angular contact ball bearings, and each is provided with one.

[0032] By adopting the above technical solution, the new front support bearing and the new rear support bearing are both angular contact ball bearings. The angular contact ball bearings are pre-tightened in the axial and radial directions and cannot move. They can play an axial and radial supporting role at the same time, ensuring that the new wave generator basically maintains no movement in the axial and radial directions.

[0033] Furthermore, the outer wall of the outer ring of the novel rear support bearing is provided with a retaining groove around its circumference, and two retaining grooves are provided along the axial direction of the novel rear support bearing, an elastomer is installed in each retaining groove, and an oil film is provided on the outer surface of the elastomer.

[0034] By adopting the above technical scheme, a retaining groove is set on the outer ring of the new rear support bearing and an elastomer is installed. The expansion amount of the elastomer is basically consistent with the inner diameter of the light alloy bearing seat, and a stable interference fit is maintained within a wide temperature range. The oil film is used to isolate the bearing outer ring and the bearing seat to prevent the bearing seat and the outer ring from contacting, prevent the outer ring from creeping, reduce wear, discoloration, abrasion and other problems, avoid the friction between the bearing and the housing caused by creep aggravating wear, avoid inducing problems such as axis deviation and tilt, and avoid the problem of poor tooth engagement leading to reduced reducer performance.

[0035] In summary, the utility model has the following beneficial effects:

[0036] 1. The utility model greatly improves the impact resistance and obtains high torque by optimizing the structure such as lengthening the axial length of the flexible wheel, increasing the inner hole diameter, increasing the tooth width, increasing the tooth width of the rigid wheel, and increasing the flexible bearing, while keeping the overall axial length and radial width of the harmonic reducer unchanged;

[0037] 2. The utility model obtains a high-torque bearing by lengthening the axial length of the cross roller bearing, increasing the number of roller rows, lengthening the axial spacing between rollers, and other structural improvements while keeping the overall axial length and radial width of the harmonic reducer unchanged, so that the harmonic reducer can obtain high torque and high moment, meeting the use requirements under more high-speed and high-load conditions;

[0038] 3. The structure of the harmonic reducer in the utility model is more compact, the internal space is further filled, the amount of grease added to the ineffective parts is reduced, and the overall amount of grease added is reduced, thereby reducing the risk of grease leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a simplified diagram of the structure of a traditional harmonic reducer;

[0040] Figure 2 It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 1;

[0041] Figure 3 It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 2;

[0042] Figure 4 It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 3;

[0043] Figure 5It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 4;

[0044] Figure 6 It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 5;

[0045] Figure 7 It is a structural schematic diagram of a high-rigidity harmonic reducer in Embodiment 6;

[0046] Figure 8 It is a structural schematic diagram of a high-rigidity harmonic reducer in Example 7.

[0047] In the figure, 01, rear cover; 02, flexible wheel; 03, cross roller bearing; 04, rigid wheel; 05, front cover; 06, flexible bearing; 07, deep groove ball bearing; 08, skeleton seal ring; 09, wave generator; 1, new rear cover; 11, step; 2, new flexible wheel; 21, thin-walled cylinder; 22, outer flange; 23, step ring; 24, lubricating oil groove; 3, new cross roller bearing; 31, bearing outer ring ; 311. Outer ring step; 32. Bearing inner ring; 33. Roller; 34. O-ring; 4. New rigid wheel; 5. New front cover; 6. New flexible bearing; 7. New front support bearing; 8. New rear support bearing; 81. Elastic retaining ring for hole; 82. Elastic retaining ring for shaft; 83. Wave ring; 84. Axial thrust bearing; 85. Thrust bearing gasket; 86. Stop groove; 87. Elastomer; 9. New wave generator. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0049] Embodiment 1:

[0050] A high stiffness harmonic reducer, such as Figure 2 As shown, it includes a new rear cover 1, a new flexible wheel 2, a new cross roller bearing 3, a new rigid wheel 4, a new front cover 5, a new flexible bearing 6, a new front support bearing 7, a new rear support bearing 8, and a new wave generator 9. Its basic structure and working principle are the same as those of the prior art, and will not be described in detail. Figure 1 and Figure 2 As shown, based on the traditional harmonic reducer structure, the main additions or improvements include the axial thin-wall length of the new flexible wheel 2, the slotting of the teeth of the new flexible wheel 2, the increased tooth width of the new flexible wheel 2, the increased tooth width of the new rigid wheel 4, the size of the new flexible bearing 6, the new cross roller bearing 3, the O-ring 34 replacing the skeleton sealing ring 08, and the increased elliptical width of the new wave generator 9.

[0051] Specifically, Figure 2 As shown, the new cross roller bearing 3 includes a bearing outer ring 31 and a bearing inner ring 32, two rows of rollers 33 are arranged in parallel along the axial direction between the bearing outer ring 31 and the bearing inner ring 32, and an O-ring 34 is arranged between the end of the bearing outer ring 31 away from the new rear cover 1 and the step surface of the bearing inner ring 32. Figure 1 and Figure 2 As shown, the traditional axially flat cross roller bearing 03 is improved into a new cross roller bearing 3 including two rows of rollers 33 arranged in parallel, and the original skeleton seal ring 08 is replaced by an O-ring 34. The outer diameter of the new cross roller bearing 3 remains unchanged, and the inner diameter becomes larger, so as to achieve radial flatness, and the larger the axial spacing between the two rows of rollers 33 in the new cross roller 33, the greater the torque obtained. Of course, in other embodiments, the O-ring 34 can also be replaced by a Gley ring or other seal rings, and if the harmonic reducer has sufficient space, the original skeleton seal ring 08 can also be used.

[0052] like Figure 2 As shown, the new flexible wheel 2 includes a coaxially arranged and integrally formed thin-walled cylinder 21, an outer flange 22 and a step ring 23. The outer flange 22 is arranged at one end of the thin-walled cylinder 21 close to the new rear cover 1 and is located between the outer ring of the thin-walled cylinder 21 and the inner ring of the step ring 23. The thickness of the outer flange 22 is less than that of the step ring 23, and the end of the outer flange 22 close to the new rear cover 1 is flush with the end of the step ring 23 close to the new rear cover 1. In addition, an outer ring step 311 is provided at one end of the bearing outer ring 31 close to the step ring 23, and the outer circle of the outer ring step 311 and the inner circle of the step ring 23 are contacted and positioned.

[0053] like Figure 1 and Figure 2As shown, the thickest part of the axial thickness in the traditional flexible wheel 02 is a stepped structure, and the step does not contact the cross roller bearing 03. The extended flange 22 in the new flexible wheel 2 moves back to the end close to the new rear cover 1 and is flush with the end of the step ring 23 close to the new rear cover 1. The outer circle of the outer ring step 311 on the outer ring 31 of the bearing and the inner circle of the step ring 23 in the new flexible wheel 2 are in contact and positioned, so that the axial length of the thin-walled tube 21 is longer, and greater flexibility is obtained. The opening inner hole of the thin-walled tube 21 is stretched to a larger range. The inner hole of the new cross roller bearing 3 is enlarged, so that the inner hole diameter of the new flexible wheel 2 can be enlarged. At the same time, the diameter of the tooth part of the thin-walled tube 21 is enlarged, and the outer diameter of the new flexible bearing 6 is synchronously increased, which greatly increases the torsional stiffness. Among them, in the improved new flexible wheel 2 in the utility model, the ratio of the axial length of the thin-walled tube 21 to its inner hole diameter is between 0.35-0.7, and the inner hole diameter of the thin-walled tube 21 can be increased to 0.5-0.7 times the maximum outer diameter of the entire harmonic reducer, and the maximum outer diameter of the entire harmonic reducer is determined by the maximum outer diameter of the new rear cover 1, the new flexible wheel 2, and the new cross roller bearing 3.

[0054] like Figure 2 As shown, the lengthening of the axial length of the thin-walled cylinder 21 of the new flexible wheel 2 further thickens the axial direction of the new cross roller bearing 3, and the arrangement and installation of the two rows of rollers 33 are easier to achieve. At the same time, the tooth width of the tooth portion of the new flexible wheel 2 is further widened, and the outer wall of the end of the thin-walled cylinder 21 close to the new front cover 5 is meshed with the inner ring teeth of the new rigid wheel 4, and the tooth widths are matched. The tooth portion can be widened to a ratio of the tooth width on the thin-walled cylinder 21 to the axial length of the thin-walled cylinder 21 between 0.3-0.5.

[0055] like Figure 2 As shown, the tooth portion of the new flexible wheel 2 is provided with a lubricating oil groove 24. In this embodiment, the lubricating oil groove 24 is located in the middle of the tooth portion and is an annular groove arranged circumferentially around the new flexible wheel 2, so as to further obtain the deformation ability of the tooth portion close to the new front cover 5 side under the action of the new rigid wheel 4, while protecting the meshing of the tooth portion close to the new rear cover 1 side with the new rigid wheel 4, and the lubricating oil groove 24 can store a certain amount of grease to ensure that the tooth portion is more fully lubricated and obtain a longer service life.

[0056] like Figure 2 As shown, the new front cover 5 and the new rigid wheel 4 are installed in plane contact, and the new front cover 5 and the new rigid wheel 4 are connected by hexagon socket flat round head screws. Figure 1 and Figure 2As shown, the tooth width of the tooth portion on the new rigid wheel 4 increases with the tooth width of the tooth portion on the thin-walled tube 21. The side of the new rigid wheel 4 close to the new front cover 5 is in direct planar contact with the new front cover 5, and the positioning hole connection between the traditional front cover 05 and the rigid wheel 04 is eliminated. The new front cover 5 and the new rigid wheel 4 are connected by hexagon socket flat round head screws. The thickness of the new front cover 5 can be thinned to the point where the screws do not protrude from the plane during installation, thereby increasing the axial thickness of the side of the new rigid wheel 4 close to the new front cover 5, which can correspondingly meet the further lengthening of the tooth width of the tooth portion of the thin-walled tube 21.

[0057] like Figure 2 As shown, since the diameter of the inner hole of the new flexible wheel 2 is enlarged and the axial length of the thin-walled tube 21 is increased, there is space to install a larger number of new flexible bearings 6, and match the gears of the new flexible wheel 2 and the gears of the new rigid wheel 4. Not only the pitch circle diameter, steel ball diameter and the total number of steel balls are greatly improved, but also the width of the outer ring of the new flexible bearing 6 in contact with the inner hole of the new flexible wheel 2 is synchronously increased, so that the load capacity of the new flexible bearing 6 is greatly improved, and the inner hole of the tooth part of the new flexible wheel 2 is supported by the outer ring of the new flexible bearing 6. Rigidity is also greatly improved. In this embodiment, as Figure 2 As shown, the novel flexible bearing 6 is provided with and includes a single row of steel balls.

[0058] like Figure 2 As shown, similarly, the inner hole diameter of the new flexible bearing 6 increases with the inner hole diameter of the new flexible wheel 2, so that the elliptical major axis and minor axis on the new wave generator 9 for mounting the new flexible bearing 6 also increase accordingly, that is, the inner hole of the new wave generator 9 is enlarged, and a large-aperture harmonic reducer is obtained. At the same time, the inner diameters of the new front support bearing 7 and the new rear support bearing 8 are synchronously increased to obtain a greater load capacity, which not only supports the stable rotation of the new wave generator 9, but also enhances the anti-axial capacity. In this embodiment, as Figure 2 As shown, the new front support bearing 7 and the new rear support bearing 8 are both deep groove ball bearings, and the new front support bearing 7 is provided with one, and the new rear support bearing 8 is provided with one, and a wave ring 83 is provided between the side close to the new rear cover 1 and the new rear cover 1, and the wave ring 83 is used to fix the new rear support bearing 8 to prevent it from axial movement.

[0059] In addition, if Figure 2As shown, the new rear cover 1 and the new front cover 5 can be made of light alloys such as aluminum alloy and magnesium alloy to reduce the weight of the reducer and increase the torque density. At this time, the outer rings of the new front support bearing 7 and the new rear support bearing 8 are matched with the bearing seats of the new front cover 5 and the new rear cover 1, which not only causes the new wave generator 9 to rotate and jump, precision loss and vibration, but also has creep problems, that is, the rotation phenomenon of the inner and outer rings of the bearings relative to the shaft and the housing during operation. Creep can cause different types of problems such as wear, discoloration, and scratches, causing friction between the bearing and the housing, accelerating the wear of both, thereby inducing problems such as axis deviation and tilt, and the resulting poor gear engagement will lead to problems such as reduced performance of the reducer.

[0060] Therefore, in this embodiment, if Figure 2 As shown, a retaining groove 86 is provided around the circumference of the outer wall of the outer ring of the new rear support bearing 8, and two retaining grooves 86 are provided along the axial direction of the new rear support bearing 8. An elastomer 87 is installed in each retaining groove 86. The elastomer 87 can be a polymer material directly injection-molded in the retaining groove 86, or an additionally installed O-ring. The expansion amount of the elastomer 87 is basically consistent with the inner diameter of the light alloy bearing seat, and a stable interference fit is maintained within a wide temperature range. High-viscosity grease is applied to form a surface oil film to prevent the bearing seat and the outer ring from contacting and preventing creep.

[0061] like Figure 2 As shown, the new rear cover 1 and the step ring 23 are installed in plane contact, the step ring 23 is located between the new rear cover 1 and the bearing outer ring 31, and the new rear cover 1 is fastened to the step ring 23 and the bearing outer ring 31 by using hexagon socket flat round head screws. Figure 1 and Figure 2 As shown, the new rear cover 1 is installed in plane contact with the new rear cover 1 and the step ring 23, and the positioning hole installation of the original rear cover 01, the flexible wheel 02 and the cross roller bearing 03 is cancelled. The new rear cover 1 is fastened with the step ring 23 and the outer ring 31 of the bearing by using hexagon socket flat round head screws. The new rear cover 1 can be thinned until the screws do not protrude from the surface, further providing space for the extension of the axial length of the thin-walled cylinder 21 and the new cross roller bearing 3. In addition, as Figure 2 As shown, a clearance step 11 is provided at a position corresponding to the inner side of the new rear cover 1 and the outer flange 22 to form a gap between the inner side and the outer flange 22 to prevent the thin-walled tube 21 from deforming and interfering with the new rear cover 1 .

[0062] like Figure 2 As shown, since the structure of the harmonic reducer in the utility model is more compact, the internal space is further filled, the amount of grease added to the ineffective parts is reduced, the overall amount of grease added is reduced, and the risk of grease leakage can be reduced.

[0063] Embodiment 2:

[0064] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 3 As shown, in this embodiment, the lubricating oil groove 24 of the tooth portion of the new flexible wheel 2 is a spiral groove spirally arranged around the outer periphery of the tooth portion of the new flexible wheel 2, which can not only lubricate the entire tooth portion, but also make the new flexible wheel 2 more improved in deformation, increase the meshing area, and increase the stability. In addition, in this embodiment, the new flexible bearing 6 is provided with one and includes two rows of steel balls arranged in parallel along its axial direction, which further improves the impact resistance and lateral swing resistance of the flexible bearing.

[0065] Embodiment three:

[0066] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 4 As shown, in this embodiment, the new flexible bearing 6 is provided with one and includes two rows of steel balls arranged in parallel along its axial direction, which further improves the impact resistance and lateral swing resistance of the flexible bearing. The new rear support bearing 8 is provided with one, and a hole elastic circlip 81 is provided between its outer ring and the new rear cover 1, and a shaft elastic circlip 82 is provided between its inner ring and the new wave generator 9. The hole elastic circlip 81 and the shaft elastic circlip 82 are used to fix the new rear support bearing 8 to prevent it from axial movement. Among them, the axial force has a weak effect on the change of the axial position of the shaft elastic circlip 82, which is generally used for harmonic reducers with larger torque.

[0067] Embodiment 4:

[0068] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 5 As shown, in this embodiment, the new flexible bearing 6 is provided with one and includes two rows of steel balls arranged in parallel along its axial direction, further improving the impact resistance and lateral swing resistance of the flexible bearing. The new rear support bearing 8 is provided with two parallel along its axial direction, and a wave ring 83 is provided on the side close to the new rear cover 1 and between the new rear cover 1. Among them, the axial force has a greater influence on the change of the axial position of the wave ring 83, which is generally used for harmonic reducers with small torque.

[0069] Embodiment five:

[0070] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 6As shown, in this embodiment, the new flexible bearing 6 is provided with one and includes two rows of steel balls arranged in parallel along its axial direction, which further improves the impact resistance and lateral swing resistance of the flexible bearing. The new rear support bearing 8 is provided with an axial thrust bearing 84 arranged in parallel with it on the side away from the new rear cover 1, and a thrust bearing pad ring 85 is provided between the axial thrust bearing 84 and the new rear cover 1. The axial thrust bearing 84 is mainly provided to bear the axial force of the new wave generator 9, and the new rear support bearing 8 and the axial thrust bearing 84 jointly support the rotation and stability of the new wave generator 9, so that not only a greater axial load capacity can be obtained, but also the volume of the new rear support bearing 8 can be greatly reduced, heat generation can be reduced, and precision can be improved.

[0071] Embodiment six:

[0072] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 7 As shown, in this embodiment, two new flexible bearings 6 are arranged in parallel along the axial direction thereof, and each new flexible bearing 6 includes a single row of steel balls, so the flexibility is stronger.

[0073] Embodiment seven:

[0074] A high-rigidity harmonic reducer, which is different from the first embodiment in that Figure 2 and Figure 8 As shown, in this embodiment, the new flexible bearing 6 is provided with one and includes two rows of steel balls arranged in parallel along its axial direction, which further improves the impact resistance and lateral swing resistance of the flexible bearing. The new front support bearing 7 and the new rear support bearing 8 are both angular contact ball bearings, and each is provided with one. The angular contact ball bearings are preloaded in both the axial and radial directions and cannot move, and can play an axial and radial support role at the same time, ensuring that the new wave generator 9 is basically maintained without moving in the axial and radial directions.

[0075] The above description shows and describes the preferred embodiments of the utility model. As mentioned above, it should be understood that the utility model is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the utility model concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the utility model, and should be within the scope of protection of the claims attached to the utility model.

Claims

1. A high-rigidity harmonic reducer, characterized in that: The invention comprises a novel rear cover (1), a novel flexible wheel (2), a novel cross roller bearing (3), a novel rigid wheel (4), a novel front cover (5), a novel flexible bearing (6), a novel front support bearing (7), a novel rear support bearing (8), and a novel wave generator (9); the novel cross roller bearing (3) comprises a bearing outer ring (31) and a bearing inner ring (32); two rows of rollers (33) are arranged in parallel between the bearing outer ring (31) and the bearing inner ring (32) along their axial direction; an O-ring (34) is arranged between the end of the bearing outer ring (31) away from the novel rear cover (1) and the step surface of the bearing inner ring (32); The novel flexible wheel (2) comprises a coaxially arranged and integrally formed thin-walled cylinder (21), an outer flange (22) and a step ring (23); the outer flange (22) is arranged at one end of the thin-walled cylinder (21) close to the novel rear cover (1) and is located between the outer ring of the thin-walled cylinder (21) and the inner ring of the step ring (23); the thickness of the outer flange (22) is less than the thickness of the step ring (23), and the end of the outer flange (22) close to the novel rear cover (1) and the end of the step ring (23) close to the novel rear cover (1) are flush; the end of the bearing outer ring (31) close to the step ring (23) is provided with an outer ring step (311), and the outer circle of the outer ring step (311) and the inner circle of the step ring (23) are in contact and fit for positioning; The ratio of the axial length of the thin-walled tube (21) to its inner hole diameter is between 0.35 and 0.7, and the inner hole diameter of the thin-walled tube (21) is 0.5 to 0.7 times the largest outer diameter of the new rear cover (1), the new flexible wheel (2), and the new cross roller bearing (3); the outer wall of one end of the thin-walled tube (21) close to the new front cover (5) is meshed with the inner ring teeth of the new rigid wheel (4), and the tooth widths are matched, and the ratio of the tooth width on the thin-walled tube (21) to the axial length of the thin-walled tube (21) is between 0.3 and 0.5; The tooth portion of the new flexible wheel (2) is provided with a lubricating oil groove (24), the lubricating oil groove (24) is located in the middle of the tooth portion and is an annular groove arranged around the circumference of the new flexible wheel (2), or the lubricating oil groove (24) is a spiral groove arranged spirally around the outer circumference of the tooth portion of the new flexible wheel (2); The new front cover (5) and the new rigid wheel (4) are installed in plane contact, the new rear cover (1) and the step ring (23) are installed in plane contact, and a clearance step (11) is provided at a position corresponding to the inner side of the new rear cover (1) and the outer flange (22) to form a gap between the inner side of the new rear cover (1) and the outer flange (22).

2. A high-rigidity harmonic reducer according to claim 1, characterized in that: The novel flexible bearing (6) is provided with and includes a single row of steel balls.

3. A high-rigidity harmonic reducer according to claim 1, characterized in that: The novel flexible bearing (6) is provided with and includes two rows of steel balls arranged in parallel along its axial direction.

4. A high-rigidity harmonic reducer according to claim 1, characterized in that: Two of the novel flexible bearings (6) are arranged in parallel along the axial direction thereof, and each novel flexible bearing (6) comprises a single row of steel balls.

5. A high-rigidity harmonic reducer according to claim 2, 3 or 4, characterized in that: The new front support bearing (7) and the new rear support bearing (8) are both deep groove ball bearings. The new rear support bearing (8) is provided with one or two are provided in parallel along its axial direction, and a hole elastic retaining ring (81) is provided between its outer ring and the new rear cover (1), and a shaft elastic retaining ring (82) is provided between its inner ring and the new wave generator (9).

6. A high-rigidity harmonic reducer according to claim 2, 3 or 4, characterized in that: The new front support bearing (7) and the new rear support bearing (8) are both deep groove ball bearings. The new rear support bearing (8) is provided with one or two are arranged in parallel along its axial direction, and a wave ring (83) is provided between the side close to the new rear cover (1) and the new rear cover (1).

7. A high-rigidity harmonic reducer according to claim 2, 3 or 4, characterized in that: The novel front support bearing (7) and the novel rear support bearing (8) are both deep groove ball bearings. The novel rear support bearing (8) is provided with an axial thrust bearing (84) arranged in parallel with the novel rear cover (1) on the side thereof away from the novel rear cover (1). A thrust bearing gasket (85) is provided between the axial thrust bearing (84) and the novel rear cover (1).

8. A high-rigidity harmonic reducer according to claim 2, 3 or 4, characterized in that: The novel front support bearing (7) and the novel rear support bearing (8) are both angular contact ball bearings, and each is provided with one.

9. The high-rigidity harmonic reducer according to claim 1, characterized in that: The outer wall of the outer ring of the novel rear support bearing (8) is provided with a retaining groove (86) around its circumference, and two retaining grooves (86) are provided along the axial direction of the novel rear support bearing (8), an elastomer (87) is installed in each retaining groove (86), and an oil film is provided on the outer surface of the elastomer (87).

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