Harmonic reducer and robot

Abstract

The utility model discloses a kind of harmonic reducer and robot, it is related to the technical field of speed reducer.Harmonic reducer includes rigid wheel, flexible wheel, wave generator and bearing, by setting the outer ring of bearing and rigid wheel connection, inner ring and flexible wheel connection, bearing plays the role of supporting rotation to rigid wheel and flexible wheel, ensure the fluency of rotation.Due to the first raceway and second raceway formed between outer ring and inner ring, and the first raceway and second raceway are separated by limit ring, the rotation of inner ring and outer ring is supported by two rows of rollers, the overturning moment and moment rigidity of bearing can be effectively improved, meet use demand.Due to the first raceway and second raceway are enclosed by inner ring, outer ring, limit ring and first annular stop, and first annular stop and outer ring are split structure, so it is not necessary to set roller filling port in the first raceway and second raceway, and also can conveniently fill roller, and effectively limit roller, to reduce vibration, to reduce the noise of bearing operation.

Description

Technical Field

[0001] This utility model relates to the field of speed reducer technology, and in particular to a harmonic speed reducer and robot. Background Technology

[0002] Harmonic reducers typically use crossed roller bearings as support bearings. In special scenarios, harmonic reducers have high requirements for overturning moment and moment rigidity, which existing crossed roller bearings cannot meet. Furthermore, to facilitate roller filling during cross roller bearing assembly, roller filling slots need to be provided on the inner or outer ring of the cross roller bearing. This disrupts the integrity of the raceway, reduces the smoothness of roller operation, and leads to increased vibration and noise during harmonic reducer operation. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a harmonic reducer that can improve the overturning moment and moment rigidity of the bearing, and eliminates the need for additional roller filler openings, thereby reducing bearing operating noise and vibration.

[0004] This utility model also proposes a robot having the above-mentioned harmonic reducer.

[0005] The harmonic reducer according to a first aspect of the present invention includes: a rigid wheel; A flexible wheel is disposed within the rigid wheel; A wave generator is embedded in the inner hole of the flexible wheel, and the wave generator is configured to cause the outer teeth of the flexible wheel to mesh with the inner teeth of the rigid wheel when rotated; The bearing includes an outer ring, a first annular stop, an inner ring, a first roller group, and a second roller group. One end of the outer ring is connected to the rigid wheel, and the other end of the outer ring is connected to the first annular stop. The inner ring is disposed in the inner hole of the outer ring and is connected to the flexible wheel. A limiting ring is provided around the outer peripheral wall of the inner ring. Along the axial direction of the harmonic reducer, the limiting ring is spaced apart from the first annular stop and the rigid wheel. The second annular stop is connected to the end of the rigid wheel facing the outer ring, or to the end of the inner circumferential wall of the outer ring facing the rigid wheel; A first raceway is formed between the limiting ring and the second annular stop, and a second raceway is formed between the limiting ring and the first annular stop. The first roller group is disposed in the first raceway, and the second roller group is disposed in the second raceway.

[0006] The harmonic reducer according to the embodiment of this utility model has at least the following beneficial effects: By connecting the outer ring of the bearing to the rigid wheel and the inner ring to the flexible wheel, the rotation of the wave generator drives the flexible wheel and the rigid wheel to rotate relative to each other. The bearing supports the rotation of the rigid wheel and the flexible wheel, ensuring smooth rotation. Since a first raceway and a second raceway are formed between the outer and inner rings, and the first and second raceways are separated by a limiting ring, the rotation of the inner and outer rings is supported by two rows of rollers, effectively improving the bearing's overturning moment and moment rigidity to meet usage requirements. Because the first and second raceways are enclosed by the inner ring, outer ring, limiting ring, and first annular stop, and the first annular stop and outer ring are separate structures, there is no need to set roller filling ports in the first and second raceways. This allows for easy filling of rollers and effective limiting of the rollers, thereby reducing vibration and lowering bearing operating noise.

[0007] According to some embodiments of the present invention, the first roller group includes a plurality of first rollers, and the rotation axes of the plurality of first rollers are perpendicular to the central axis of the harmonic reducer.

[0008] According to some embodiments of the present invention, the second roller group includes a plurality of third rollers and a plurality of fourth rollers, with at least one fourth roller provided between two adjacent third rollers, the rotation axes of the plurality of third rollers being perpendicular to the central axis of the harmonic reducer, and the rotation axes of the plurality of fourth rollers being parallel to the central axis of the harmonic reducer.

[0009] According to some embodiments of the present invention, the number of the third roller and the number of the fourth roller are the same, and the third roller and the fourth roller are arranged alternately along the second raceway.

[0010] According to some embodiments of the present invention, the first roller group includes a plurality of first rollers, the first roller, the third roller and the fourth roller are respectively cylindrical, the maximum outer diameter of the first roller is D1, the maximum outer diameter of the third roller is D3 and the maximum outer diameter of the fourth roller is D4, satisfying: D3=D4>D1.

[0011] According to some embodiments of this utility model, the inner diameter of the flexible wheel is Dr, which satisfies: 0.035≤D1 / Dr≤0.075; 1.3≤D3 / D1≤1.7.

[0012] According to some embodiments of the present invention, the first roller group includes a plurality of first rollers and a plurality of second rollers, with at least one second roller provided between two adjacent first rollers; the second roller group includes a plurality of third rollers and a plurality of fourth rollers, with at least one fourth roller provided between two adjacent third rollers. The rotation axes of the plurality of first rollers and the plurality of third rollers are perpendicular to the central axis of the harmonic reducer, and the rotation axes of the plurality of second rollers and the plurality of fourth rollers are parallel to the central axis of the harmonic reducer.

[0013] According to some embodiments of this utility model, the number of the first roller is n1, the number of the second roller is n2, the number of the third roller is n3, and the number of the fourth roller is n4, satisfying: 0.5 ≤ n1 / n ≤ 0.7; 0.3≤n2 / n≤0.5, where n1=n3; n2=n4; n=n1+n2.

[0014] According to some embodiments of this utility model, two first rollers are respectively arranged between every two adjacent second rollers; and / or, Two third rollers are arranged between each pair of adjacent fourth rollers.

[0015] According to some embodiments of this utility model, the first roller, the second roller, the third roller, and the fourth roller are each cylindrical. The maximum outer diameter of the first roller is D1, the maximum outer diameter of the second roller is D2, the maximum outer diameter of the third roller is D3, the maximum outer diameter of the fourth roller is D4, and the inner diameter of the flexible wheel is Dr, satisfying: 0.04≤D1 / Dr≤0.082; and / or, 0.04≤D² / Dr≤0.082; and / or, 0.04≤D3 / Dr≤0.082; and / or, 0.04≤D4 / Dr≤0.082.

[0016] According to some embodiments of the present invention, the maximum outer diameter D1 of the first roller, the maximum outer diameter D2 of the second roller, the maximum outer diameter D3 of the third roller, and the maximum outer diameter D4 of the fourth roller satisfy the following condition: D1=D2=D3=D4.

[0017] According to some embodiments of the present invention, the second annular stop is connected to the end of the inner peripheral wall of the outer ring facing the rigid wheel, and is integrally formed with the outer ring; or, The second annular stop is connected to the rigid wheel and is integrally formed with the rigid wheel; or, The second annular stop is connected between the rigid wheel and the outer ring by fasteners.

[0018] The robot according to a second aspect of the present invention includes the harmonic reducer described in the above embodiments.

[0019] The robot according to the embodiments of this utility model has at least the following beneficial effects: By employing the harmonic reducer of the first aspect embodiment, the harmonic reducer connects the outer ring of the bearing to the rigid wheel and the inner ring to the flexible wheel. When the wave generator rotates, it drives the flexible wheel and the rigid wheel to rotate relative to each other. The bearing supports the rotation of the rigid wheel and the flexible wheel, ensuring smooth rotation. Since a first raceway and a second raceway are formed between the outer and inner rings, and the first and second raceways are separated by a limiting ring, the rotation of the inner and outer rings is supported by two rows of rollers, effectively improving the overturning moment and moment rigidity of the bearing, meeting usage requirements. Because the first and second raceways are enclosed by the inner ring, outer ring, limiting ring, and a first annular stop, and the first annular stop and outer ring are separate structures, it is not necessary to provide roller filling ports in the first and second raceways. This allows for convenient filling of rollers and effective limiting of the rollers, thereby reducing vibration and lowering the noise of the bearing operation.

[0020] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a cross-sectional view of a harmonic reducer according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the bearing portion structure according to an embodiment of the present invention; Figure 3 yes Figure 2 Another perspective view of the bearing section structure; Figure 4 This is a partial structural cross-sectional view of the outer ring of one embodiment of the present invention; Figure 5 This is a partial structural cross-sectional view of the inner ring of one embodiment of this utility model; Figure 6 This is a front view of the first roller according to an embodiment of the present invention; Figure 7 This is a front view of the third roller according to an embodiment of the present invention; Figure 8 This is a front view of the fourth roller according to an embodiment of the present invention; Figure 9 This is a graph showing the relationship between the D1 / Dr ratio, allowable overturning moment, and overall weight of one embodiment of this utility model. Figure 10 This is a graph showing the relationship between the ratio of D3 / D1 or D4 / D1 and the allowable overturning moment and the weight of the whole machine in one embodiment of this utility model. Figure 11 This is a cross-sectional view of a harmonic reducer according to another embodiment of the present invention; Figure 12 This is a schematic diagram of the bearing portion structure of another embodiment of the present invention; Figure 13 yes Figure 12 Another perspective view of the bearing section structure; Figure 14 This is a front view of the second roller according to an embodiment of the present invention; Figure 15 This is a graph showing the relationship between the D / Dr ratio, allowable overturning moment, and overall weight of another embodiment of this utility model. Figure 16 This is a graph showing the relationship between the ratio of n1 / n and the allowable overturning moment and vibration acceleration in another embodiment of this utility model.

[0022] Figure label: Harmonic reducer 1000; Bearing 100; outer ring 110; second annular stop 111; inner ring 120; limiting ring 121; mounting groove 122; first roller group 130; first roller 131; second roller 132; Second roller group 140; Third roller 141; Fourth roller 142; First annular stop 150; First raceway 160; Second raceway 170; Oil seal 180; Rigid wheel 200; Flexible wheel 300; Wave generator 400. Detailed Implementation

[0023] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0024] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0025] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0026] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0027] Harmonic reducers, operating under high loads and high precision conditions, require high overturning moment bearing capacity and torque rigidity in their support bearings, which existing crossed roller bearings often fail to meet. Traditional designs commonly use crossed roller bearings as the support structure, but these bearings have drawbacks when dealing with complex operating conditions. Because the inner or outer ring of a crossed roller bearing requires pre-reserved filling openings for assembly, the integrity of the raceway is compromised, leading to irregular runout and impacts during roller operation. This not only reduces the smoothness of bearing operation but also exacerbates the overall vibration and noise levels of the harmonic reducer, affecting the stability and service life of the equipment.

[0028] To solve the above problems, refer to Figure 1 , Figure 2 and Figure 3 As shown, a harmonic reducer 1000 according to an embodiment of the present invention can be used in a robot. The harmonic reducer 1000 according to an embodiment of the present invention includes a rigid wheel 200, a flexible wheel 300, a wave generator 400, and a bearing 100. The flexible wheel 300 is disposed inside the rigid wheel 200; the wave generator 400 is embedded in the inner hole of the flexible wheel 300, and the wave generator 400 is configured to mesh with the outer teeth of the flexible wheel 300 and the inner teeth of the rigid wheel 200 when rotating.

[0029] Reference Figure 1 , Figure 4 and Figure 5As shown, the bearing 100 includes an outer ring 110, a first annular stop 150, an inner ring 120, a first roller group 130, and a second roller group 140. One end of the outer ring 110 is connected to the rigid wheel 200, and the other end of the outer ring 110 is connected to the first annular stop 150. The inner ring 120 is disposed in the inner hole of the outer ring 110 and is connected to the flexible wheel 300. A limiting ring 121 is provided around the outer peripheral wall of the inner ring 120. Along the axial direction of the harmonic reducer 1000, the limiting ring 121, the first annular stop 150, and the rigid wheel 200 are spaced apart. The harmonic reducer 1000 also includes a second annular stop 111, which can be connected to the end of the rigid wheel 200 facing the outer ring 110 or to the end of the inner peripheral wall of the outer ring 110 facing the rigid wheel 200.

[0030] A first raceway 160 is formed between the limiting ring 121 and the second annular stop 111, and a second raceway 170 is formed between the limiting ring 121 and the first annular stop 150. A first roller group 130 is disposed in the first raceway 160, and a second roller group 140 is disposed in the second raceway 170.

[0031] It should be noted that the outer ring 110 of the bearing 100 serves as an external fixed frame, with one end connected to the rigid wheel 200 and the other end connected to the first annular stop 150. This split design can be achieved through bolt connection, allowing the roller filling to be completed without damaging the integrity of the raceway during assembly. The limiting ring 121 is located on the outer peripheral wall of the inner ring 120, and its position and size can be adjusted according to the axial interval. For example, by processing annular structures of different widths to adapt to different raceway spacing requirements, the independence and stability of the first raceway 160 and the second raceway 170 are ensured. The first roller group 130 and the second roller group 140 are respectively located on the first raceway 160 and the second raceway 170, and can be arranged in an alternating or parallel manner to distribute the composite load and enhance the overall support capacity. When the second annular stop 111 is connected to the rigid wheel 200, it can be integrally formed with the rigid wheel 200, thereby preventing the first roller group 130 from detaching from the first raceway 160. When the second annular stop 111 is connected to the outer ring 110, it can also be integrally formed with the outer ring 110.

[0032] By adopting the above scheme, the first raceway 160 and the second raceway 170, separated by the limiting ring 121, enable the independent operation of the two rows of rollers, significantly improving the overturning moment and moment stiffness of the bearing 100. Furthermore, the separate structure design of the first annular stop 150 and the outer ring 110 eliminates the need for traditional roller filling ports, thereby reducing vibration sources and lowering operating noise. This design not only improves the overall performance of the harmonic reducer 1000 but also provides reliable assurance for its application in high-load scenarios.

[0033] Reference Figure 2 and Figure 3As shown in the embodiment of this utility model, the first roller group 130 includes a plurality of first rollers 131. The rotation axes S1 of the plurality of first rollers 131 are perpendicular to the central axis S4 of the harmonic reducer 1000, so as to improve the axial thrust of the bearing 100. The first roller 131 refers to a rolling element with a cylindrical structure. The rotation axes S1 of the plurality of first rollers 131 are perpendicular to the central axis, ensuring that the rollers form a longer effective contact area in the axial direction, thereby enhancing the axial support capacity of the bearing 100.

[0034] By rationally designing the rotation axis S1 direction of the first roller 131, the axial support performance of the bearing 100 is optimized. The first roller group 130 is composed of multiple first rollers 131. This multi-point distribution structure ensures that the load is evenly transmitted within the first raceway 160, avoiding local stress concentration. When the harmonic reducer 1000 is subjected to external axial load, since the cylindrical axis of the first roller 131 is perpendicular to the central axis and the length direction of the first roller 131 is parallel to the axial direction, greater axial stiffness is generated between the roller and raceway contact surface, effectively enhancing the ability to resist axial displacement and improving the overall torque stiffness and operational stability of the bearing 100.

[0035] Reference Figure 2 and Figure 3 As shown in the embodiment of this utility model, the second roller group 140 includes a plurality of third rollers 141 and a plurality of fourth rollers 142. At least one fourth roller 142 is provided between two adjacent third rollers 141, for example, one, two, or three fourth rollers 142 are provided between two adjacent third rollers 141. The rotation axis S3 of the plurality of third rollers 141 is perpendicular to the central axis S4 of the harmonic reducer 1000, and the rotation axis S4 of the plurality of fourth rollers 142 is parallel to the central axis S4 of the harmonic reducer 1000.

[0036] The third roller 141 refers to the type of roller in the second roller group 140 used to provide axial thrust. It can be a cylindrical roller, a tapered roller, or other structure with similar function. Its purpose is to enhance the bearing 100's resistance to overturning moment by arranging it perpendicular to the central axis of the harmonic reducer 1000. The fourth roller 142 refers to the type of roller in the second roller group 140 used to provide radial thrust. It can be a cylindrical roller, a spherical roller, or other structure with similar function. Its purpose is to provide stable radial support to cope with radial load changes by arranging it parallel to the central axis of the harmonic reducer 1000. In addition, the design of setting the fourth roller 142 between two adjacent third rollers 141 is intended to ensure the uniform distribution of rollers in the raceway, effectively disperse load stress, and avoid local concentration.

[0037] Through the above design, the third roller 141 mainly provides axial thrust and the fourth roller 142 mainly provides radial thrust, ensuring that the bearing 100 simultaneously meets the requirements of high axial rigidity and high radial rigidity during operation, ultimately achieving an increase in torque rigidity and improving the stability of the harmonic reducer 1000 under harsh operating conditions.

[0038] Reference Figure 2 As shown, in this embodiment of the present invention, the number of third rollers 141 and fourth rollers 142 is the same, and the third rollers 141 and fourth rollers 142 are arranged alternately along the second raceway 170. The fact that the number of third rollers 141 and fourth rollers 142 is the same can improve the uniformity of the overall force on the bearing 100. Furthermore, since the rotation axis S1 of the first roller 131 is perpendicular to the central axis S4 of the harmonic reducer 1000, the bearing 100 as a whole can provide a stronger axial thrust.

[0039] In the annular second raceway 170, each third roller 141 is immediately followed by a fourth roller 142. This design ensures that axial and radial thrust are uniformly transmitted in the second raceway 170, allowing the axial and radial thrust to compensate for each other and achieve dynamic balance in spatial distribution. This alternating arrangement not only optimizes the force transmission path but also eliminates local stress concentration, significantly enhancing the bearing 100's ability to resist external overturning moments. Simultaneously, it improves the overall structural rigidity and stability, ultimately reducing vibration and noise during the operation of the harmonic reducer 1000.

[0040] Reference Figure 2 and Figure 3 As shown, in an embodiment of this utility model, the first roller group 130 includes a plurality of first rollers 131, and the first rollers 131, third rollers 141, and fourth rollers 142 are respectively cylindrical. (Refer to...) Figure 6 , Figure 7 and Figure 8 As shown, the maximum outer diameter of the first roller 131 is D1, the maximum outer diameter of the third roller 141 is D3, and the maximum outer diameter of the fourth roller 142 is D4, satisfying the condition that D3 = D4 > D1. This provides suitable axial thrust while reducing the axial dimension and overall weight of the harmonic reducer 1000. It should be noted that the units for D1, D3, and D4 are all mm.

[0041] By adopting the above scheme, the maximum outer diameters of the third roller 141, the fourth roller 142, and the first roller 131 satisfy the relationship D3=D4>D1. By making the outer diameters of the third roller 141 and the fourth roller 142 consistent, the balanced distribution of thrust in the second raceway 170 is ensured. At the same time, the design that D3 and D4 are greater than D1 makes the structure of the first raceway 160 more compact, thereby effectively reducing the overall size and weight of the harmonic reducer 1000 while providing appropriate axial thrust.

[0042] Reference Figure 1 , Figure 6 , Figure 7 and Figure 8 As shown, in this embodiment of the present invention, the inner diameter of the flexible wheel 300 is Dr, with the unit of Dr being mm, and satisfies the following conditions: 0.035≤D1 / Dr≤0.075, 1.3≤D3 / D1≤1.7, 1.3≤D4 / D1≤1.7. Specifically, the values ​​of D1 / Dr can be 0.035, 0.04, 0.05, 0.06, or 0.075; the values ​​of D3 / D1 can be 1.3, 1.4, 1.5, 1.6, or 1.7; and the values ​​of D4 / D1 can be 1.3, 1.4, 1.5, 1.6, or 1.7. It should be noted that the inner diameter Dr of the flexible wheel 300 refers to the diameter of the inner hole of the flexible wheel 300, which can be used as a reference parameter to determine the relative size ratio of the first roller 131 and the third roller 141.

[0043] Reference Figure 9 As shown, Figure 9 The horizontal axis represents the value of D1 / Dr, the left vertical axis represents the allowable overturning moment, and the right vertical axis represents the total weight of the machine. Figure 9 As can be seen, both the allowable overturning moment and the overall weight gradually increase with the increase of the D1 / Dr ratio. Therefore, when D1 / Dr is less than the specified range, the size of the first roller 131 is too small, providing insufficient support and resulting in insufficient allowable overturning moment. When D1 / Dr is greater than the specified range, although the allowable overturning moment increases, the overall weight also becomes too large, resulting in excessive strength redundancy and an increase in overall size. Therefore, by setting the D1 / Dr ratio between 0.035 and 0.075, the relationship between the allowable overturning moment and the overall weight can be balanced, ensuring that the maximum outer diameter D1 of the first roller 131 matches the structure of the flexible wheel 300, thereby providing sufficient support.

[0044] Reference Figure 10 As shown, Figure 10 The horizontal axis represents the value of D3 / D1 or D4 / D1, the vertical axis on the left represents the allowable overturning moment, and the vertical axis on the right represents the weight of the entire machine. Figure 10As can be seen, as the values ​​of D3 / D1 or D4 / D1 gradually increase, the allowable overturning moment first gradually increases and then tends to remain constant, while the overall weight initially remains constant and then gradually increases. Therefore, when D3 / D1 is less than the specified range, the size of the first roller 131 is too small, resulting in a small allowable overturning moment and insufficient support. When D3 / D1 is greater than the specified range, although the allowable overturning moment increases, the size of the bearing 100 is too large, increasing the overall weight and causing excessive strength redundancy. Therefore, the ratio range of D3 / D1 and D4 / D1 is limited to between 1.3 and 1.7, which can balance the relationship between the allowable overturning moment and the overall weight, allowing the third roller 141 to provide appropriate axial thrust while avoiding structural redundancy, thus balancing the support performance of the bearing 100 with structural compactness.

[0045] Reference Figure 11 , Figure 12 and Figure 13 As shown, in another embodiment of the present invention, the first roller group 130 includes a plurality of first rollers 131 and a plurality of second rollers 132, with at least one second roller 132 disposed between two adjacent first rollers 131; the second roller group 140 includes a plurality of third rollers 141 and a plurality of fourth rollers 142, with at least one fourth roller 142 disposed between two adjacent third rollers 141; the rotation axes S1 of the plurality of first rollers 131 and S3 of the plurality of third rollers 141 are perpendicular to the central axis S4 of the harmonic reducer 1000, and the rotation axes S2 of the plurality of second rollers 132 and S4 of the plurality of fourth rollers 142 are parallel to the central axis S4 of the harmonic reducer 1000.

[0046] The alternating arrangement of the first roller 131 and the second roller 132 optimizes the distribution of axial and radial loads through roller distribution in different directions. The alternating arrangement of the third roller 141 and the fourth roller 142 enhances the bearing 100's resistance to overturning moments. It should be noted that in other embodiments, the arrangement of the first roller 131, the second roller 132, the third roller 141, and the fourth roller 142 can be adjusted according to specific working conditions to ensure uniform distribution of multi-directional forces within a limited space.

[0047] Reference Figure 12 and Figure 13 As shown, in the embodiment of this utility model, the number of first rollers 131 is n1, the number of second rollers 132 is n2, the number of third rollers 141 is n3, and the number of fourth rollers 142 is n4, satisfying: 0.5≤n1 / n≤0.7; 0.3≤n2 / n≤0.5; where n1=n3; n2=n4; n=n1+n2.

[0048] Reference Figure 16 As shown, Figure 16The horizontal axis represents the ratio of n1 / n or n3 / n, the left vertical axis represents the allowable overturning moment, and the right vertical axis represents the vibration acceleration. As shown in the graph, as the ratio of n1 / n or n3 / n gradually increases, the allowable overturning moment gradually increases, while the vibration acceleration initially decreases slightly and then increases sharply. Generally, lower vibration acceleration is better, and higher allowable overturning moment is better; however, a higher allowable overturning moment can also lead to increased cost and size.

[0049] Therefore, n1=n3 ensures that the axial thrust is evenly distributed on both sides of the bearing 100, avoiding vibration and stress concentration caused by thrust imbalance. n2=n4 ensures the symmetry of radial support, preventing deflection problems caused by insufficient radial rigidity. Meanwhile, the introduction of the ratio range 0.5≤n1 / n≤0.7 is due to the need for the axial thrust rollers to occupy a dominant position. This range avoids the defect of insufficient axial support when the proportion is too low, and also prevents the radial stability from being weakened by crowding out the radial roller space when the proportion is too high, ensuring that the axial thrust is maximized. When the number of first rollers 131 is greater than the number of second rollers 132, the bearing 100 provides more axial thrust. In another embodiment, when the number of second rollers 132 is greater than the number of first rollers 131, the bearing 100 can provide more radial thrust. Therefore, the relationship between the number of first rollers 131 and second rollers 132 is selected according to actual needs.

[0050] Reference Figure 12 and Figure 13 As shown in the embodiment of this utility model, two first rollers 131 are arranged between every two adjacent second rollers 132. Two third rollers 141 are arranged between every two adjacent fourth rollers 142. The arrangement of two first rollers 131 between adjacent second rollers 132 increases the number of axial support points, enabling more even distribution of axial loads, avoiding localized stress concentration, and significantly enhancing the bearing 100's ability to resist overturning moments. Simultaneously, the arrangement of two third rollers 141 between every two adjacent fourth rollers 142 also increases the axial thrust of the bearing 100.

[0051] Reference Figure 1 , Figure 6 , Figure 7 , Figure 8 and Figure 14As shown, in the embodiment of this utility model, the first roller 131, the second roller 132, the third roller 141, and the fourth roller 142 are all cylindrical. The maximum outer diameter of the first roller 131 is D1, the maximum outer diameter of the second roller 132 is D2, the maximum outer diameter of the third roller 141 is D3, the maximum outer diameter of the fourth roller 142 is D4, and the inner diameter of the flexible wheel 300 is Dr, satisfying: 0.04≤D1 / Dr≤0.082; 0.04≤D2 / Dr≤0.082; 0.04≤D3 / Dr≤0.082; 0.04≤D4 / Dr≤0.082.

[0052] The cylindrical design of the first roller 131, second roller 132, third roller 141, and fourth roller 142 refers to their cylindrical external profile. This design facilitates precise control of dimensional proportions and ensures the feasibility of manufacturing and assembly. The proportional range of the maximum outer diameters D1, D2, D3, and D4 is set based on the optimization of the inner bore diameter Dr of the flexspline 300, aiming to balance support force and structural compactness through reasonable dimensional design.

[0053] Reference Figure 15 As shown, Figure 15 The horizontal axis represents the value of D / Dr, the left vertical axis represents the allowable overturning moment, and the right vertical axis represents the overall weight. D / Dr is used to refer to any of the values ​​in the above embodiments. From Figure 15 As can be seen from this, as the value of D / Dr gradually increases, the allowable overturning moment gradually increases, while the weight of the whole machine first remains small and then gradually increases.

[0054] When D / Dr is less than 0.04, the outer diameter of the roller is too small, resulting in insufficient thrust and a small allowable overturning moment, making it difficult to meet the relevant requirements. When D / Dr is greater than 0.082, although sufficient overturning moment can be provided, the outer diameter of the roller is too large, leading to an increase in the overall size of the bearing 100 and the weight of the entire machine. Therefore, in order to balance the relationship between thrust and size, limiting the D / Dr ratio to the range of 0.04 to 0.082 can increase thrust while making the overall structure of the bearing 100 more compact, which is beneficial for the miniaturization design of the bearing 100.

[0055] Reference Figure 1 As shown in the embodiment of this utility model, the maximum outer diameter D1 of the first roller 131, the maximum outer diameter D2 of the second roller 132, the maximum outer diameter D3 of the third roller 141, and the maximum outer diameter D4 of the fourth roller 142 satisfy: D1=D2=D3=D4, and the first roller 131, the second roller 132, the third roller 141, and the fourth roller 142 have the same external dimensions. Therefore, the types of rollers can be reduced, and the selection difficulty can be lowered.

[0056] The above technical solution can reduce the types of rollers and lower the difficulty of selection, while taking into account the support performance and assembly convenience of bearing 100, thereby achieving the goal of optimizing the overall performance of harmonic reducer 1000.

[0057] Reference Figure 1 and Figure 4 As shown in the embodiment of this utility model, a second annular stop 111 is provided at the end of the inner peripheral wall of the outer ring 110 facing the rigid wheel 200. The second annular stop 111 is used to restrict the first roller group 130 from disengaging from the first raceway 160. The second annular stop 111 refers to an annular structure provided on the inner peripheral wall of the outer ring 110, which can be implemented by integral molding or separate connection. This structural layout can not only constrain the position of the first roller group 130, but also avoid the problem of destroying the integrity of the raceway due to the setting of roller filling holes in traditional designs, thereby ensuring the stability and reliability of the bearing 100 operation.

[0058] It should be noted that in other embodiments, the second annular stop 111 can also be connected between the outer ring 110 and the rigid wheel 200 by fasteners such as screws or bolts. That is, the second annular stop 111, the outer ring 110, and the rigid wheel 200 are separate designs, and the appropriate solution is selected according to the actual situation.

[0059] Reference Figure 1 and Figure 5 As shown in the embodiment of this utility model, an installation groove 122 is provided at the end of the outer peripheral wall of the outer ring 110 away from the rigid wheel 200. An annular groove for installing the oil seal 180 is formed between the wall surface of the installation groove 122 and the inner peripheral wall of the first annular stop 150. The lubricating oil of the oil seal 180 for the first raceway 160 and the second pipe on the wall surface seeps out through the annular groove.

[0060] One embodiment of the robot of this utility model includes the harmonic reducer 1000 of the above embodiment. The robot of this utility model adopts the harmonic reducer 1000 of the above embodiment. By setting the outer ring 110 of the bearing 100 to connect with the rigid wheel 200, and the inner ring 120 to connect with the flexible wheel 300, when the wave generator 400 rotates, it drives the flexible wheel 300 and the rigid wheel 200 to rotate relative to each other. The bearing 100 supports the rotation of the rigid wheel 200 and the flexible wheel 300, ensuring smooth rotation. Since a first raceway 160 and a second raceway 170 are formed between the outer ring 110 and the inner ring 120, and the first raceway 160 and the second raceway 170 are separated by a limiting ring 121, the rotation of the inner ring 120 and the outer ring 110 is supported by two rows of rollers, which can effectively improve the overturning moment and moment rigidity of the bearing 100, meeting the usage requirements. Since the first raceway 160 and the second raceway 170 are formed by the inner ring 120, the outer ring 110, the limiting ring 121 and the first annular stop 150, and the first annular stop 150 and the outer ring 110 are separate structures, it is not necessary to set roller filling ports in the first raceway 160 and the second raceway 170. Rollers can be easily filled and effectively limited, thereby reducing vibration and lowering the noise of the bearing 100 during operation.

[0061] Since the robot adopts all the technical solutions of the harmonic reducer 1000 of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0062] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A harmonic reducer, characterized in that, include: Rigid wheel; A flexible wheel is disposed within the rigid wheel; A wave generator is embedded in the inner hole of the flexible wheel, and the wave generator is configured to cause the outer teeth of the flexible wheel to mesh with the inner teeth of the rigid wheel when rotated; The bearing includes an outer ring, a first annular stop, an inner ring, a first roller group, and a second roller group. One end of the outer ring is connected to the rigid wheel, and the other end of the outer ring is connected to the first annular stop. The inner ring is disposed in the inner hole of the outer ring and is connected to the flexible wheel. A limiting ring is provided around the outer peripheral wall of the inner ring. Along the axial direction of the harmonic reducer, the limiting ring is spaced apart from the first annular stop and the rigid wheel. The second annular stop is connected to the end of the rigid wheel facing the outer ring, or to the end of the inner circumferential wall of the outer ring facing the rigid wheel; A first raceway is formed between the limiting ring and the second annular stop, and a second raceway is formed between the limiting ring and the first annular stop. The first roller group is disposed in the first raceway, and the second roller group is disposed in the second raceway.

2. The harmonic reducer according to claim 1, characterized in that: The first roller group includes a plurality of first rollers, and the rotation axis of the plurality of first rollers is perpendicular to the central axis of the harmonic reducer.

3. The harmonic reducer according to claim 1 or 2, characterized in that: The second roller group includes a plurality of third rollers and a plurality of fourth rollers, with at least one fourth roller between two adjacent third rollers. The rotation axes of the plurality of third rollers are perpendicular to the central axis of the harmonic reducer, and the rotation axes of the plurality of fourth rollers are parallel to the central axis of the harmonic reducer.

4. The harmonic reducer according to claim 3, characterized in that: The number of the third roller is the same as the number of the fourth roller, and the third roller and the fourth roller are arranged alternately along the second raceway.

5. The harmonic reducer according to claim 3, characterized in that: The first roller group includes multiple first rollers. The first roller, the third roller, and the fourth roller are all cylindrical. The maximum outer diameter of the first roller is D1, the maximum outer diameter of the third roller is D3, and the maximum outer diameter of the fourth roller is D4, satisfying: D3=D4>D1.

6. The harmonic reducer according to claim 5, characterized in that: The inner diameter of the flexible wheel is Dr, which satisfies: 0.035≤D1 / Dr≤0.075; 1.3≤D3 / D1≤1.

7.

7. The harmonic reducer according to claim 1, characterized in that: The first roller group includes a plurality of first rollers and a plurality of second rollers, with at least one second roller between two adjacent first rollers; the second roller group includes a plurality of third rollers and a plurality of fourth rollers, with at least one fourth roller between two adjacent third rollers. The rotation axes of the plurality of first rollers and the plurality of third rollers are perpendicular to the central axis of the harmonic reducer, and the rotation axes of the plurality of second rollers and the plurality of fourth rollers are parallel to the central axis of the harmonic reducer.

8. The harmonic reducer according to claim 7, characterized in that: The number of the first roller is n1, the number of the second roller is n2, the number of the third roller is n3, and the number of the fourth roller is n4, satisfying: 0.5 ≤ n1 / n ≤ 0.7; 0.3≤n2 / n≤0.5; where n1=n3, n2=n4, n=n1+n2.

9. The harmonic reducer according to claim 7, characterized in that: Two first rollers are arranged between each pair of adjacent second rollers; and / or, Two third rollers are arranged between each pair of adjacent fourth rollers.

10. The harmonic reducer according to claim 7, characterized in that: The first roller, the second roller, the third roller, and the fourth roller are all cylindrical. The maximum outer diameter of the first roller is D1, the maximum outer diameter of the second roller is D2, the maximum outer diameter of the third roller is D3, and the maximum outer diameter of the fourth roller is D4. The inner diameter of the flexible wheel is Dr, satisfying the following: 0.04≤D1 / Dr≤0.082; and / or, 0.04≤D² / Dr≤0.082; and / or, 0.04≤D3 / Dr≤0.082; and / or, 0.04≤D4 / Dr≤0.

082.

11. The harmonic reducer according to claim 10, characterized in that: The maximum outer diameter D1 of the first roller, the maximum outer diameter D2 of the second roller, the maximum outer diameter D3 of the third roller, and the maximum outer diameter D4 of the fourth roller satisfy the following condition: D1=D2=D3=D4.

12. The harmonic reducer according to claim 1, characterized in that: The second annular stop is connected to the end of the inner circumferential wall of the outer ring facing the rigid wheel, and is integrally formed with the outer ring; or, The second annular stop is connected to the rigid wheel and is integrally formed with the rigid wheel; or, The second annular stop is connected between the rigid wheel and the outer ring by fasteners.

13. A robot, characterized in that: Including the harmonic reducer as described in any one of claims 1 to 12.

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