Oscillating tooth speed reducer

Abstract

The utility model provides a movable tooth speed reducer which comprises a crossed roller bearing capable of bearing radial and axial loads and a movable tooth transmission mechanism capable of achieving the speed reduction function. The oscillating tooth transmission mechanism comprises an input end cam, an oscillating tooth isolation ring, oscillating teeth and an inner gear ring, the oscillating teeth are arranged in a plurality of evenly-arranged oscillating tooth grooves of the oscillating tooth isolation ring, the inner gear ring is used for being connected with the oscillating teeth in a meshed mode, and one side of each oscillating tooth is connected with the input end cam in a rolling mode. The other side of the oscillating tooth is in meshed connection with the inner gear ring and is used for performing tangent motion with an inner tooth profile to drive the oscillating tooth isolation ring to perform rotary motion; the crossed roller bearing comprises a crossed roller bearing outer ring, a roller and a crossed roller bearing inner ring, and the oscillating tooth isolation ring is fixedly connected with the crossed roller bearing inner ring through a bolt. The transmission mechanism with the small tooth difference is good in rigidity, stable in operation, large in transmission ratio, small in return difference, long in service life and low in maintenance cost.

Description

Technical Field

[0001] This utility model relates to the field of speed reducer technology, specifically to a live gear speed reducer capable of axial and radial loads. Background Technology

[0002] Current cycloidal reducers all require a crankshaft and eccentric bearing assembly, resulting in complex structures, high manufacturing difficulty, and large size and weight. As the robotics industry demands increasingly smaller cycloidal reducers, the need for miniaturized models remains a significant challenge. However, existing cycloidal reducers cannot be miniaturized due to the crankshaft requirement.

[0003] To address this issue, there is still room for improvement in existing speed reducers. Utility Model Content

[0004] To address the aforementioned shortcomings, the purpose of this invention is to provide a high-precision, high-efficiency axially and radially loaded movable gear reducer that retains the advantages of existing cycloidal reducers while featuring a simple structure and miniaturized manufacturing, thereby solving the problems of the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A movable-tooth reducer includes a crossed roller bearing capable of withstanding radial and axial loads and a movable-tooth transmission mechanism capable of speed reduction. The movable-tooth transmission mechanism includes an input cam, a movable-tooth isolation ring, movable teeth disposed in a plurality of evenly arranged movable-tooth slots on the isolation ring, and an internal gear ring for meshing with the movable teeth. One side of each movable tooth is rolledly connected to the input cam as an input component of the transmission mechanism; the other side of each movable tooth meshes with the internal gear ring for tangential motion with the internal tooth profile, driving the movable-tooth isolation ring to rotate. The crossed roller bearing includes an outer ring, rollers, and an inner ring, with the rollers disposed between the outer and inner rings. The movable-tooth isolation ring is fixedly connected to the inner ring by bolts; the movable-tooth isolation ring drives the inner ring to move.

[0007] According to the embodiments of this application, the meshing between the live gear and the internal gear ring is a slight interference fit and a multi-tooth meshing transmission, wherein the number of teeth of the internal gear ring and the number of teeth of the live gear differ by two.

[0008] According to the embodiments of this application, the cross roller bearing of the live gear reducer further includes a sealing ring for preventing lubricating grease leakage.

[0009] According to the embodiments of this application, the live gear reducer further includes a radial ball bearing, which is positioned between the inner ring of the crossed roller bearing and the live gear isolation ring; the input end cam is positioned within the inner hole of the radial ball bearing.

[0010] According to the embodiments of this application, the live gear reducer is a spherical or roller gear.

[0011] According to the embodiments of this application, the live gear reducer further includes an input shaft bearing retaining ring, which is bolted to one end of the input end cam.

[0012] According to the embodiments of this application, the live gear reducer further includes a housing, and the housing, the internal gear ring, and the outer ring of the crossed roller bearing are fixedly connected by bolts.

[0013] The design concept of this application is to design a live gear reducer that can withstand axial and radial loads. Its performance retains the advantages of a transmission cycloidal reducer, and its simple structure greatly improves miniaturization and manufacturability. At the same time, it is equipped with a dedicated cross roller bearing, which can achieve good precision and rigidity through preload. Furthermore, it can use a tapered inner ring to adjust the bearing clearance arbitrarily. It can withstand not only radial loads but also axial loads, thus greatly improving its applicability.

[0014] Due to the adoption of the above technical features, this utility model has the following advantages and positive effects compared with the prior art:

[0015] First, this application is a transmission mechanism with a small tooth difference, which has good rigidity, smooth operation, large transmission ratio and small backlash, making the reducer of this application have a long service life and low maintenance cost.

[0016] Secondly, the inner ring of the crossed roller bearing in this application, as the output part, can withstand radial and axial loads in all directions.

[0017] Of course, any specific embodiment of the present invention may not necessarily have all of the above technical effects at the same time. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the reducer in this application;

[0019] Figure 2 yes Figure 1 Schematic diagram of the AA section;

[0020] Figure 3 This is a schematic diagram of the active tooth isolation ring of this application;

[0021] Figure 4This is a schematic diagram of another active tooth isolation ring in this application. Detailed Implementation

[0022] For ease of understanding, the preferred embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0023] Please refer to Figure 1 This application presents a cross-sectional view of a speed reducer. The speed reducer is a compact device composed of two parts: a crossed roller bearing capable of withstanding radial and axial loads, and a live-tooth transmission mechanism that enables speed reduction. The speed reduction section employs a live-tooth transmission mechanism, essentially a crankshaft-less cycloidal speed reducer. The meshing between the live teeth and the internal gear ring uses a slight interference fit, and during transmission, it involves multi-tooth meshing. Furthermore, this application utilizes a low-tooth-difference transmission mechanism, resulting in high rigidity, smooth operation, a large transmission ratio, and low backlash. Using the crossed roller bearing inner ring as the output part, this application can withstand radial and axial loads from all directions and can be widely used in robot joint transmissions, automated actuators, and precision machine tools.

[0024] like Figure 1 and Figure 2 As shown, the reducer described in this application includes a crossed roller bearing capable of withstanding radial and axial loads and a live gear transmission mechanism capable of reducing speed. In addition, the inner ring 14 of the crossed roller bearing in this application serves as the output part and can withstand radial and axial loads in all directions. After the input speed of the cam 2 at the input end is reduced by the live gear transmission mechanism, the reduced rotational speed is transmitted from the output shaft (not shown in the figure) connected to the inner ring 14 of the crossed roller bearing.

[0025] In addition, the movable gear transmission mechanism includes an input end cam 2, a movable gear isolation ring 5, movable teeth 6 disposed in a plurality of evenly arranged movable gear grooves 51 in the movable gear isolation ring 5, and an internal gear ring 7 for meshing and connecting the movable teeth 6, such as Figure 2 As shown, the internal teeth of the internal gear ring 7 are cycloidal gears, and the outer edge of the internal gear ring 7 is a smooth surface; one side of the movable tooth 6 is rolledly connected to the input end cam 2 for the input component of the transmission mechanism, and the other side of the movable tooth 6 meshes with the internal teeth of the internal gear ring 7, and moves tangentially with the internal tooth profile, thereby driving the movable tooth isolation ring 5 to rotate; the number of movable tooth slots 51 is the number of movable tooth slots required under theoretical calculation, but in practice, there may be a situation where the distance between adjacent movable tooth slots 51 is too small to manufacture when arranged according to the theoretical number of movable tooth slots. In this case, tooth reduction can be performed according to the requirements of the deceleration movable tooth transmission mechanism of this application, that is, the number of movable tooth slots 51 is uniformly reduced to meet the manufacturability of the movable tooth isolation ring 5.

[0026] Figure 1The crossed roller bearing includes an outer ring 11, rollers 12, and an inner ring 14. The outer ring 11 and inner ring 14 are provided with evenly distributed threaded holes and bolt through holes for connecting other parts of this application. The rollers 12 are disposed between the outer ring 11 and inner ring 14, and are disposed in such a manner that a roller receiving groove is formed on the outer surface of the inner ring 14, and a corresponding roller receiving groove is formed on the outer surface of the outer ring 11. During assembly, the rollers 12 are placed in these two corresponding and enclosed roller receiving grooves. Figure 1 As shown, there is a gap between the two corresponding and enclosed roller receiving grooves; the movable tooth isolation ring 5 is fixedly connected to the inner ring 14 of the cross roller bearing by bolts, that is, the movable tooth isolation ring 5 and the inner ring 14 of the cross roller bearing are assembled into one piece. Under this design, when the movable tooth isolation ring 5 rotates, it simultaneously drives the inner ring 14 of the cross roller bearing to move, and the movement of the inner ring 14 of the cross roller bearing is a decelerated speed output.

[0027] Furthermore, the meshing between the movable tooth 6 and the internal gear ring 7 is a slight interference fit and a multi-tooth meshing transmission. The number of teeth in the internal gear ring 7 differs from the number of teeth in the movable tooth 6 by two. In this embodiment, the number of teeth in the internal gear ring 7 is 14, and the number of teeth in the movable tooth 6 is 12. However, this cannot be used to limit this application. As long as the number of teeth meets the deceleration requirements, it should be within the scope of protection of this application. This application is also a transmission mechanism with a small tooth difference, so it has good rigidity, smooth operation, large transmission ratio, and small backlash. In addition, due to the special nature of the movable tooth transmission, the number of teeth in the internal gear ring 7 can also be 2 fewer than the number of teeth in the movable tooth 6.

[0028] Figure 1 In this embodiment, the crossed roller bearing also includes a sealing ring 13. In this embodiment, there are two sealing rings 13, which are respectively disposed on both sides of the gap between the two roller receiving grooves. The function of the sealing ring 13 is to prevent the leakage of grease that serves as lubrication.

[0029] Figure 1In this configuration, the movable gear transmission mechanism further includes a radial ball bearing 3, which is positioned between the inner ring 14 of the crossed roller bearing and the movable gear isolation ring 5. An input end cam 2 is positioned within the inner hole of the radial ball bearing 3. The radial ball bearing 3 is installed between the inner ring 14 of the crossed roller bearing and the movable gear isolation ring 5, allowing the radial ball bearing 3 to be axially positioned. The input end cam 2 is positioned and installed within the radial ball bearing 3 through its inner hole; that is, after assembly, the input end cam 2 can rotate within the radial ball bearing 3, and the inner ring 14 of the crossed roller bearing and the movable gear isolation ring 5 can rotate on the radial ball bearing 3.

[0030] Please refer to Figure 3 and Figure 4 This application presents a schematic diagram of a toothed isolating ring. The tooth 6 is either spherical or roller-shaped. When the tooth 6 is spherical, the toothed isolating ring 5 is... Figure 3 As shown; when the movable tooth 6 is a roller, the movable tooth isolation ring 5 is Figure 4 As shown, Figure 3 and Figure 4 The difference lies in the shape of the tooth groove 51 of the assembled tooth 6; the tooth 6 performs radial reciprocating motion under the drive of the input end cam 2, and the number of layers of the tooth 6 can be set to one or more layers according to the wall thickness requirement of the tooth isolation ring 5, such as... Figure 3 and Figure 4 As shown, in this embodiment of the application, the number of layers of the movable teeth 6 is one, and the number of movable teeth 6 in each layer is two.

[0031] like Figure 1 As shown, the movable gear transmission mechanism also includes an input shaft bearing retaining ring 9. The input shaft bearing retaining ring 9 is bolted to one end of the input end cam 2. During assembly, the input end cam 2 is positioned and installed in the radial ball bearing 3 through the inner hole of the radial ball bearing 3. One end face is fixed by the input shaft bearing retaining ring 9 and tightened with bolts. After assembly, the input end cam 2 can rotate smoothly in the radial ball bearing 3. Furthermore, the movable gear transmission mechanism also includes a housing 4. The housing 4, the internal gear ring 7, and the outer ring 11 of the crossed roller bearing are fixedly connected by bolts. The connection method is as follows: after the housing 4 mates with the internal gear ring 7, it is installed onto the outer ring 11 of the crossed roller bearing, and then fixed with bolts. As mentioned above, the outer ring 11 of the crossed roller bearing is provided with evenly distributed bolt through holes for connecting other parts of this application. Here, the bolts connect the housing 4, the internal gear ring 7, and the outer ring 11 of the crossed roller bearing through the bolt through holes.

[0032] The transmission described in this application is a double-shock wave planetary reduction mechanism with live teeth. The input cam 2 is equivalent to the sun gear of the planetary reducer. The profile of the input cam 2 is elliptical. When the input cam 2 rotates around its center, the live teeth 6, which are radially evenly arranged in the live tooth groove 51 of the live tooth isolation ring 5, will slide back and forth radially. That is, the live teeth 6 and the live tooth groove 51 are in sliding fit. The internal gear ring 7 is fixedly mounted on the outer shell 4. The tooth profile of the internal teeth of the internal gear ring 7 is set according to the tangential motion trajectory of the live teeth 6. The number of teeth of the internal teeth and the theoretical number of live teeth 6 form a two-tooth difference. Thus, for every half-turn of the input cam 2, the live teeth 6 slide back and forth radially once, and the live teeth 6 also move tangentially with the internal tooth profile by one tooth profile. The live teeth 6 also move tangentially due to the tangential component force. This tangential motion simultaneously drives the live tooth isolation ring 5 to rotate. This rotational motion is a two-tooth-difference deceleration motion.

[0033] Next, let's explain the reduction ratio. The reduction ratio of this application is i = -(z2-z1) / z1 (where: z1 is the theoretical number of live tooth slots 51, and z2 is the number of teeth on the internal gear ring. Normally, z2-z1 = 2, but due to the special nature of live tooth transmission, the number of teeth on the internal gear ring can be 2 fewer than the theoretical number of live tooth slots 51, i.e., z2-z1 = -2). Since this application is directly input by the input end cam 2, there is no need for an eccentric shaft, and the motion trajectory of the live tooth transmission mechanism as the reduction mechanism is equivalent to that of a cycloidal reducer, this application is also called a crankshaftless cycloidal reducer. Because the crankshaft mechanism is eliminated, the volume of this application is smaller and the weight is lighter than that of the existing cycloidal reducer.

[0034] In summary, the profile of the input cam 2 is a double-eccentric semi-circular arc, with the two semi-circular arcs connected by a straight line transition; the tooth profile of the internal gear ring 7 is an internal cycloidal tooth profile, and its tooth profile profile can be consistent with the trajectory of the moving tangent surface of the movable tooth 6, ensuring the continuity of the movement of the movable tooth transmission mechanism that can realize the deceleration function; the output is carried by the dedicated cross roller bearing, which can realize radial and axial all-round load; the deceleration part is realized by the movable tooth transmission mechanism, and the implementation method is as follows: the input cam 2 is the driving element, the internal gear ring 7 is fixed, and the movable tooth 6 and the movable tooth isolation ring 5 are the deceleration output end; when the input cam 2 rotates around the center line, the movable tooth isolation ring 5 will decelerate and rotate to output according to the set transmission ratio.

[0035] It should be noted that in the description of the embodiments of this application, the terms "front," "rear," "left," "right," "up," "down," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application. The terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0036] Due to the adoption of the above technical features, this utility model has the following advantages and positive effects compared with the prior art:

[0037] First, this application is a transmission mechanism with a small tooth difference, which has good rigidity, smooth operation, large transmission ratio and small backlash, making the reducer of this application have a long service life and low maintenance cost.

[0038] Secondly, the inner ring of the crossed roller bearing in this application, as the output part, can withstand radial and axial loads in all directions.

[0039] The above-disclosed embodiments are merely preferred embodiments of the present utility model, but are not intended to limit the scope thereof. Any equivalent changes and modifications made by those skilled in the art without departing from the spirit and essence of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A movable gear reducer, characterized in that, The reducer includes crossed roller bearings capable of withstanding radial and axial loads and a movable gear transmission mechanism capable of achieving speed reduction. The movable tooth transmission mechanism includes an input end cam, a movable tooth isolation ring, movable teeth disposed in a plurality of evenly arranged movable tooth grooves in the movable tooth isolation ring, and an internal tooth ring for meshing with the movable teeth. One side of the movable teeth is rolledly connected to the input end cam for use as the input component of the transmission mechanism; the other side of the movable teeth is meshed with the internal tooth ring for tangential motion with the internal tooth profile to drive the movable tooth isolation ring to rotate. The crossed roller bearing includes an outer ring, rollers, and an inner ring. The rollers are disposed between the outer ring and the inner ring. The movable tooth isolation ring is fixedly connected to the inner ring by bolts. The movable tooth isolation ring drives the movement of the inner ring.

2. The movable gear reducer as described in claim 1, characterized in that, The engagement between the live tooth and the internal gear ring is a slight interference fit and a multi-tooth meshing transmission. The number of teeth on the internal gear ring differs from the number of teeth on the live tooth by two.

3. The movable gear reducer as described in claim 2, characterized in that, The crossed roller bearing also includes a seal to prevent lubricant leakage.

4. The movable gear reducer as described in claim 3, characterized in that, The live gear transmission mechanism also includes a radial ball bearing, which is positioned between the inner ring of the crossed roller bearing and the live gear isolation ring; the input end cam is positioned within the inner hole of the radial ball bearing.

5. The movable gear reducer as described in claim 4, characterized in that, The movable teeth are spherical or roller-shaped.

6. The movable gear reducer as described in claim 5, characterized in that, The live gear transmission mechanism also includes an input shaft bearing retainer ring, which is bolted to one end of the input end cam.

7. The movable gear reducer as described in claim 6, characterized in that, The live gear transmission mechanism also includes a housing, and the housing, the internal gear ring, and the outer ring of the crossed roller bearing are fixedly connected by bolts.

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