Flexible pin-tooth wave reducer

Abstract

The flexible pin tooth wave reducer includes a wave generator assembly, a flexible gear, and an internal gear assembly, wherein the internal gear assembly includes an internal gear body, pin tooth assemblies, and pin tooth spacers, wherein the pin tooth assemblies are uniformly distributed in the small holes of the internal gear body, and the wave generator assembly includes a wave generator body and a wave generator bearing, wherein the wave generator bearing is attached between the wave generator body and the flexible gear, and the flexible gear and the internal gear assembly are connected by a flexible gear support bearing to realize coaxial motion, and the pin tooth structure degenerates the equidistant line or equivalent tooth profile of the circular tooth profile of the internal gear into a circle or point with a radius of zero, thereby simultaneously meshing the flexible gear with all the teeth of the internal gear.

Description

[Technical Field]

[0001] The present invention relates to the technical field of reducers, and in particular to flexible pin tooth wave reducers. [Background technology]

[0002] Wave reducers are high-speed reducers with large reduction ratios and have been successfully applied in the robotics industry. They feature a compact structure, a large gear ratio, and a small number of components. However, these reducers also have a fatal flaw: their gear tooth profiles typically consist of two curves, one on each side. Examples of these tooth profiles include the double-arc tooth profile from the former Soviet Union, the S-shaped tooth profile from Japan, and the P-shaped tooth profile from Suzhou Green Company, as shown in Figure 1. These tooth profiles are prone to various interferences during structural design, which must be avoided by reducing the number of simultaneously meshing teeth. While both flexsplines and internal gears have a large number of teeth, only 20-30% of the teeth are in simultaneous contact. Increasing the number of simultaneously meshing teeth is an important development direction for wave reducers. Furthermore, severe line-contact sliding friction exists between the flexible gear and the internal gear, which is designed with such multi-stage curved tooth profiles, resulting in tooth wear. This not only limits the transmission efficiency of the reducer (currently generally not exceeding 70%), but also severely limits the reducer's service life and load-bearing capacity.

[0003] Furthermore, in order for the current wave reducer structure to achieve multiple tooth meshing and uniform load, it is necessary to improve the manufacturing precision of the gears, which increases the manufacturing costs of the reducer. Therefore, it is very important to find a wave reducer structure that can achieve uniform load while reducing costs. Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the shortcomings of the prior art, the present invention provides a flexible pin tooth wave reducer to solve the problems presented in the background art above. [Means for solving the problem]

[0005] To achieve the above object, the present invention provides a flexible pin tooth wave reducer as a technical means, which includes a wave generator assembly, a flexible gear, and an internal gear assembly, wherein the flexible gear is located between the internal gear assembly and the wave generator assembly; The internal gear assembly includes an internal gear body, a pin tooth assembly, and a pin tooth spacer, wherein the flexible gear is located inside the internal gear body, the pin tooth assembly is installed in a set of imperfect semicircular small holes uniformly distributed on the inner cylindrical surface of the internal gear body, and the pin tooth spacer is located at one end of the pin tooth assembly and prevents the pin tooth assembly from moving axially, and the pin tooth assembly comes into surface contact with the set of imperfect semicircular small holes of the internal gear body to realize sliding, thereby reducing contact stress and wear between the teeth, and comes into contact with the flexible gear to realize rolling friction, thereby improving load-bearing capacity and transmission efficiency.

[0006] The wave generator assembly includes a wave generator body and a wave generator bearing, the wave generator body is located inside the flexible gear, its outer shape is actually a cylindrical cam, the cutting line of the cam is an ellipse or other curve close to an ellipse, the shape of the tooth profile of the flexible gear can be adjusted by modifying the shape of the curve, or the shape of the curve can be modified by adjusting the shape of the tooth profile of the flexible gear, the wave generator bearing is located on the surface of the cam structure outside the wave generator body and contacts the outer end of the inner surface of the flexible gear, When the body rotates, the wave generator bearing can press all the teeth of the flexible gear to cause it to deform radially, and the tooth profiles of the outer ring of the flexible gear, which has two or more fewer teeth than the internal gear assembly, are brought into contact with the pin tooth assemblies of the internal gear assembly in sequence, and the flexible gear is driven to rotate at a low speed relative to the internal gear assembly, so that the flexible gear can deform radially and also rotate slightly tangentially, and further achieve a deceleration effect in which the rotational speed of the flexible gear is much lower than the rotational speed of the wave generator; The flexible gear has a flexible gear support bearing installed at its other outer end, and is connected to the flexible gear and the internal gear assembly via the flexible gear support bearing, thereby realizing coaxial motion between the flexible gear and the internal gear assembly. By using a pin tooth structure for the internal gear, the equivalent curve of the cylindrical tooth profile of the internal gear is degenerated to a single point or a circle with a radius of zero, thereby solving the problem of multiple tooth profile interference that exists when a multi-stage curve is used between the internal gear and the flexspline of the wave reducer. All the teeth of the flexible gear and all the teeth of the internal gear are simultaneously engaged, and the number of simultaneously engaged teeth is increased from 20 to 30% of conventional wave reducers to nearly 100%, significantly improving the load-bearing capacity of the reducer and reducing its volume.

[0007] Preferably, a first wave generator bearing retaining plate is provided at the front end of the pin tooth assembly, and a first wave generator spring collar is provided at the front end of the first wave generator bearing retaining plate to prevent the pin tooth from moving axially into the incomplete small hole.

[0008] Preferably, second wave generator bearing retaining plates are installed on the outer wall surfaces on both sides of the wave generator body, and second wave generator spring collars are installed on both sides close to the axis of the second wave generator bearing retaining plates, respectively, to ensure the stability of the axial position of the wave generator bearing and the wave generator body.

[0009] Preferably, the area where the internal gear body and the flexible gear contact each other further has rigidity control grooves, the number of which is equal to the number of the pin tooth assemblies, arranged in sequence, and the rigidity control grooves are uniformly distributed on the internal gear body and alternately correspond to the number of teeth of the pin tooth assemblies.

[0010] Preferably, the stiffness control groove controls the magnitude of the tangential stiffness of the teeth of the pin tooth assembly, and the actual shape and dimensions of the stiffness control groove are adjusted according to the actual stiffness and limit load of the reducer so as to be able to control the uniformity of the load on each pin tooth with a certain manufacturing accuracy.

[0011] Preferably, the flexible gear support bearing is respectively provided with a first connecting screw and a second connecting screw, the first connecting screw is located on the outer ring of the flexible gear support bearing, the second connecting screw is located on the inner ring of the flexible gear support bearing, the flexible gear support bearing and the internal gear body are connected by the first connecting screw, and the flexible gear support bearing and the flexible gear are connected by the second connecting screw.

[0012] Preferably, steel balls or rollers are provided around the interior of the wave generator bearing.

[0013] Preferably, for the tooth profile curve of the flexible gear, the coordinate origin and coordinate axes of each tooth of the gear can be determined in accordance with the principle that the arc length and distance from the intersection point between the center line of the tooth of the flexible gear and the outer ring of the wave generator bearing to the end point of the major axis or minor axis of the ellipse-like curve of the wave generator remain unchanged from the arc length and distance before deformation, and that the center line of the tooth is perpendicular to the ellipse-like curve of the wave generator, and further the tooth profile curve can be determined in accordance with the meshing principle.

[0014] Preferably, a radial undercut groove is installed between the pin tooth assembly and the internal gear body, so that both ends of the pin tooth are supported and the central portion is raised, and by appropriately reducing and controlling the radial rigidity of the pin tooth, the load uniformity when the pin tooth assembly and multiple teeth of the flexible gear come into contact is adjusted and controlled, thereby improving the load-bearing capacity and effectively preventing seizure. [Effects of the Invention]

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. The present invention provides a flexible pin tooth wave reducer, which changes the sliding friction between the internal gear and the teeth of the flexspline of a conventional wave reducer to rolling friction and surface contact sliding friction between the pin teeth and the imperfect cylindrical small holes in the internal gear body, and utilizes the large contact area between the pin teeth and the pin tooth case to improve the operating conditions of sliding friction, thereby improving the conventional efficiency, significantly improving the load-bearing capacity, and extending its service life. It is expected that this solution will improve the transmission efficiency of the wave reducer from below 70% to above 80%.

[0017] 2. The present invention provides a solution for forming grooves on the internal gear to distribute the load evenly, thereby realizing uniform load and reducing the manufacturing precision requirements. Stiffness control grooves with a certain shape and length are cut into the internal gear to reduce the stiffness of the internal gear teeth, ensuring that the stiffness meets the design requirements at rated load. This also reduces the manufacturing precision requirements of the reducer, further reducing the manufacturing costs of the wave reducer.

[0018] 3. In this invention, by using an internal gear with a pin tooth structure, the equivalent tooth profile of the circular tooth profile curve of the internal gear can be degenerated to a single point (the center of the pin tooth), avoiding various interference problems that exist when multiple tooth profile curves form a single tooth profile. In theory, all teeth of the flexspline can be simultaneously meshed with all teeth of the internal gear, which is at least one time more than the number of simultaneously meshing teeth of a typical wave reducer. The use of pin teeth enables simultaneous meshing of all teeth, greatly improving the load-bearing capacity of the reducer. Given the same load-bearing capacity requirements, it is expected that the volume and weight of the wave reducer can be further reduced, which is of great significance for the development of space robots and humanoid robots. [Brief explanation of the drawings]

[0019] The drawings are intended to provide a further understanding of the invention, constitute a part of the specification, and are used to interpret the invention together with the examples of the invention, but are not intended to limit the invention.

[0020] [Figure 1]1A to 1C are schematic diagrams of tooth profiles of some typical wave reducers. [Figure 2] FIG. 2 is a cross-sectional view of the shaft of the flexible pin tooth wave reducer of the present invention. [Figure 3] FIG. 1 is a cross-sectional view of a flexible pin tooth wave reducer of the present invention. [Figure 4] FIG. 2 is a diagram illustrating the transmission principle of the flexible pin tooth wave reducer of the present invention in the initial position. [Figure 5] FIG. 2 is a diagram illustrating the transmission principle at an arbitrary position of the flexible pin tooth wave reducer of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] Preferred embodiments of the present invention will be described below with reference to the drawings. However, it should be understood that the preferred embodiments described here are merely for the purpose of explaining and interpreting the present invention and are not intended to limit the present invention.

[0022] In the pin tooth structure used in the internal gear of a general cycloidal pin wheel reducer, there is a semi-cylindrical coupling surface between the pin tooth and the pin tooth case, and the pin tooth can slide relative to the semi-circular hole of the internal gear. Because the contact area between them is large, sliding friction with oil film separation can be achieved when the clearance design and load are appropriate. In this case, the cycloid wheel and the pin tooth are still in line contact, but the contact between the pin tooth and the cycloid wheel is rolling friction, which not only significantly improves the transmission efficiency of the reducer but also reduces wear caused by sliding friction between the internal gear and the flexspline teeth.

[0023] Therefore, the present invention provides a flexible pin tooth wave reducer, and as shown in Figures 2 and 3, the flexible pin tooth wave reducer includes a wave generator assembly 1, a flexible gear 2, and an internal gear assembly 3, and the flexible gear is located between the internal gear assembly 3 and the wave generator assembly 1; The internal gear assembly 3 includes an internal gear body 301, a pin tooth assembly 303, and a pin tooth spacer 302. The flexible gear 2 is located inside the internal gear body 301. The pin tooth assembly 303 is mounted in a set of incomplete semicircular small holes uniformly distributed on the inner cylindrical surface of the internal gear body 301. The pin tooth gasket and spring stop ring prevent the pin teeth from moving axially in the pin tooth case. A radial undercut groove is formed between the pin tooth assembly 303 and the internal gear body 301. By installing the pin tooth, both ends of the pin tooth are supported and the center is raised, and by appropriately reducing and controlling the radial rigidity of the pin tooth, the load uniformity when the pin tooth assembly 303 and the multiple teeth of the flexible gear 2 contact each other is adjusted and controlled, thereby improving the load-bearing capacity and effectively preventing seizure. The pin tooth spacer 302 is located at one end of the pin tooth assembly 303 and prevents the pin tooth assembly 303 from moving in the axial direction. The front end of the pin tooth assembly 303 is provided with a first wave A first wave generator bearing retaining plate 103 is installed, and a first wave generator spring collar 102 is installed at the front end of the first wave generator bearing retaining plate 103 to prevent the pin teeth from moving axially into the incomplete small hole. In the area where the internal gear body 301 and the flexible gear 2 contact each other, stiffness control grooves, the number of which is the same as the number of the pin tooth assemblies 303, are further installed in order, and the stiffness control grooves are uniformly distributed on the internal gear body 301 and alternately correspond to the number of teeth of the pin tooth assemblies 303. The actual shape and dimensions of the stiffness control groove are adjusted according to the actual stiffness and limit load of the reducer so as to control the load uniformity on each pin tooth with a certain manufacturing precision. The pin tooth assembly 303 comes into surface contact with a set of imperfect semicircular small holes in the internal gear body 301 to achieve sliding, thereby reducing contact stress and wear between the teeth, and comes into contact with the flexible gear 2 to achieve rolling friction, thereby improving load-bearing capacity and transmission efficiency.

[0024] The wave generator assembly 1 includes a wave generator body 101 and a wave generator bearing 104. The wave generator body 101 is located inside the flexible gear 2, and its external shape is actually a cylindrical cam. The cutting line of the cam is an ellipse or another curve close to an ellipse. The shape of the curve can be adjusted by modifying the shape of the curve, or the shape of the curve can be modified by adjusting the shape of the tooth profile of the flexible gear 2. The wave generator bearing 104 is located on the surface of a cam structure outside the wave generator body 101. Steel balls or rollers are installed inside the wave generator bearing 104 and contact the outer end of the inner surface of the flexible gear 2. Second wave generator bearing retaining plates 305 are installed on the outer wall surfaces on both sides of the wave generator body 101, and the second wave generator bearing retaining plates 305 On both sides close to the axis, there are respectively installed second wave generator spring collars 304, which ensure the axial positional stability of the wave generator bearing 104 and the wave generator body 101. When the wave generator body 101 rotates, the wave generator bearings 104 can press all the teeth of the flexible gear 2, causing it to deform radially. The tooth profiles of the outer ring of the flexible gear 2, which has two or more fewer teeth than the internal gear assembly 3, are sequentially brought into contact with the pin tooth assemblies 303 of the internal gear assembly 3, driving the flexible gear 2 to rotate at a low speed relative to the internal gear assembly 3, thereby realizing radial deformation of the flexible gear 2 and slight tangential rotation, and further achieving a deceleration effect in which the rotational speed of the flexible gear 2 is much lower than that of the wave generator. The flexible gear 2 has a flexible gear support bearing 5 installed at the outer end on the other side, which is connected to the flexible gear 2 and the internal gear assembly 3 respectively through the flexible gear support bearing 5, thereby further realizing coaxial movement of the flexible gear 2 and the internal gear assembly 3. The flexible gear support bearing 5 is provided with a first connecting screw 4 and a second connecting screw 6, the first connecting screw 4 being located on the outer ring of the flexible gear support bearing 5, the second connecting screw 6 being located on the inner ring of the flexible gear support bearing 5, the flexible gear support bearing 5 and the internal gear body 301 being connected by the first connecting screw 4, the flexible gear support bearing 5 and the flexible gear 2 being connected by the second connecting screw 6, and the tooth profile curve of the flexible gear 2 is such that the arc length and distance from the intersection point between the center line of the teeth of the flexible gear 2 and the outer ring of the wave generator bearing 104 and the intersection point to the end point of the major axis or minor axis of the elliptical curve of the wave generator remain unchanged from the arc length and distance before deformation, and the tooth is perpendicular to the elliptical curve of the wave generator, the coordinate origin and coordinate axes of each tooth of the gear can be determined, and the tooth profile curve can be determined according to the meshing principle. By using a pin tooth structure for the internal gear, the equivalent curve of the cylindrical tooth profile of the internal gear can be degenerated to a single point or a circle with a radius of zero, thereby solving the problem of multiple tooth profile interference that exists when a multi-stage curve is used between the internal gear and flexspline of the wave reducer. All of the teeth of the flexible gear 2 and all of the teeth of the internal gear can be meshed simultaneously, and the number of simultaneously meshing teeth is increased from 20 to 30% of that of conventional wave reducers to nearly 100%, significantly improving the load-bearing capacity of the reducer and reducing its volume.

[0025] Figure 4 shows the transmission principle of the flexible pin tooth wave reducer in the initial position. 10 is the outer contour of the wave generator body 101, on the outside of which steel balls or rollers of radius D1 are uniformly distributed, and on the outside of the steel balls there is a flexible gear 2 of thickness H2, and S 20 is the root curve S of flexible gear 2 20 and O 30 and R 30 are the initial center position and radius of the first pin tooth of the internal gear assembly 3, respectively, and S210 and S 21 are the theoretical and actual tooth profiles of the first tooth of the flexible gear 2, respectively. Point P is the curve S of the first tooth of the flexible gear 2. 20 It is the point located on the tooth, which is also the coordinate origin of the tooth, PX 41 -Y 41 is the local coordinate system of the tooth.

[0026] Figure 5 is a diagram of the transmission principle at any position of the flexible pin tooth wave reducer. When the flexible gear 2 does not rotate, and the rotation angle of the wave generator assembly 1 relative to the flexible gear 2 is A1, and the rotation angle of the internal gear assembly 3 relative to the flexible gear 2 is A3, X1 and X3 are the positions of the X-axis coordinate axes of the wave generator assembly 2 and the internal gear assembly 3, respectively, and R is the position of point P on the flexible gear 2 at that time. The corresponding first tooth coordinate system is RX 42 -Y 42 O3 is the position of the center of the first pin tooth of the internal gear assembly 3 at that time, and S 220 and S 22 are the theoretical and actual tooth profiles of the first tooth of flexible gear 2 at that time, respectively. O1 is the intersection point of flexible gear 2 and axis X1. This point is one of the minor axis endpoints of curve S2. Since the position of flexible gear 2 during deformation is always on the X1 axis (there is a slight change, but this can be ignored), it can be considered a fixed point related to the tooth profile; that is, its angular position is the same as the angular position at the initial position. Assuming that the perimeter of root curve S2 of flexible gear 2 is maintained unchanged, the position of point R can be determined based on the arc length of the initial position of that point relative to point O1.

[0027] To design the complete gear tooth profile, the wave generator assembly 1 may be rotated 90 degrees relative to the flexible gear 2, taking into account the symmetry of the tooth profile. In this section, the motion locus of point R and the equation of the tangent at point R of the S2 curve are obtained, and the coordinate system RX is calculated. 42 -Y 42 Assuming that the tooth profile of the flexible gear 2 does not change significantly in the core process, the coordinate system RX of point O3 can be calculated based on the coordinate transformation.42 -Y 42 The equation of relative motion for the curve S 220 is the equation, and S 22 and S 220 The actual tooth profile S of the first tooth of the flexible gear 2 is determined based on the equidistant relationship between 22 can be obtained.

[0028] In addition, a solution that is the exact opposite of the above structural proposal of exchanging the internal and external tooth structures is included, namely, changing the flexspline teeth of Figures 2 and 3 to pin teeth and changing the internal gear to a general gear, i.e., a gear with integrated teeth and base, thereby further reducing the radial rigidity of the flexible gear 2 and lowering the requirements for material fatigue strength.

[0029] Finally, it should be noted that the above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art may still modify the technical means described in the above embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. [Explanation of symbols]

[0030] 1 Wave generator assembly 101 Wave generator body 102 First Wave Generator Spring Collar 103 First wave generator bearing stopper plate 104 Wave Generator Bearing 2 Flexible gears 3 Internal gear assembly 301 Internal gear body 302 Pin tooth spacer 303 Pin tooth assembly 304 Second Wave Generator Spring Collar 305 Second wave generator bearing stopper plate 4 First connecting screw 5 Flexible gear support bearing 6 Second connecting screw

Claims

1. a wave generator assembly, a flex gear, and an internal gear assembly; the flexible gear is located between the internal gear assembly and the wave generator assembly; The internal gear assembly includes an internal gear body, a pin tooth assembly, and a pin tooth spacer, the flexible gear is located inside the internal gear body, the pin tooth assembly is located in a set of imperfect semicircular small holes uniformly distributed on the internal cylindrical surface of the internal gear body, the pin tooth spacer is located at one end of the pin tooth assembly and prevents the pin tooth assembly from moving axially, the pin tooth assembly comes into surface contact with the imperfect small holes of the internal gear body to realize sliding friction, and comes into contact with the flexible gear to realize rolling friction, thereby improving load-bearing capacity and transmission efficiency, The wave generator assembly includes a wave generator body and a wave generator bearing, the wave generator body is located inside the flexible gear, the wave generator bearing is located on the surface of a cam structure outside the wave generator body and contacts the outer end of the inner surface of the flexible gear, when the wave generator body rotates, the wave generator bearing presses the flexible gear to deform in the radial direction, and the tooth profile of the outer ring of the flexible gear, which has two or more fewer teeth than the internal gear assembly, sequentially contacts the pin tooth assembly of the internal gear assembly, driving the flexible gear to rotate at a low speed relative to the internal gear assembly, thereby achieving the effect of deceleration; The flexible gear has a flexible gear support bearing installed at the outer end of the other side, which is connected to the flexible gear and the internal gear assembly respectively through the flexible gear support bearing, and further realizes the coaxial movement of the flexible gear and the internal gear assembly. The pin tooth structure is used to degenerate the cylindrical pin tooth profile of the internal gear into a single point or a circle with a radius of zero, thereby solving the tooth profile interference between the internal gear and the flexible gear, and all the teeth of the flexible gear and all the teeth of the internal gear are simultaneously meshed. A flexible pin tooth wave reducer characterized by:

2. a first wave generator bearing retaining plate is provided at the front end of the pin tooth assembly, and a first wave generator spring collar is provided at the front end of the first wave generator bearing retaining plate to prevent the pin tooth assembly from moving axially relative to the internal gear body; 2. The flexible pin tooth wave reducer according to claim 1.

3. A second wave generator bearing retaining plate is installed on each outer wall surface on both sides of the wave generator body, and a second wave generator spring collar is installed on both sides close to the axis of the second wave generator bearing retaining plate, which ensures the stability of the axial position of the wave generator bearing and the wave generator body.

2. The flexible pin tooth wave reducer according to claim 1.

4. The area where the internal gear body and the flexible gear contact each other is provided with stiffness control grooves, the number of which is equal to the number of the pin tooth assemblies, and the stiffness control grooves are uniformly distributed on the internal gear body and alternately correspond to the number of teeth of the pin tooth assemblies.

2. The flexible pin tooth wave reducer according to claim 1.

5. the rigidity control groove controls the magnitude of the tangential rigidity of the teeth of the pin tooth assembly, and the actual shape and dimensions of the rigidity control groove are adjusted according to the actual rigidity and limit load of the reducer so as to be able to control the uniformity of the load on each pin tooth with a certain manufacturing accuracy.

5. The flexible pin tooth wave reducer according to claim 4.

6. The flexible gear support bearing is respectively provided with a first connecting screw and a second connecting screw, the first connecting screw is located on the outer ring of the flexible gear support bearing, the second connecting screw is located on the inner ring of the flexible gear support bearing, the flexible gear support bearing and the internal gear body are connected by the first connecting screw, and the flexible gear support bearing and the flexible gear are connected by the second connecting screw.

2. The flexible pin tooth wave reducer according to claim 1.

7. Steel balls or rollers are disposed around the inside of the wave generator bearing.

2. The flexible pin tooth wave reducer according to claim 1.

8. The tooth profile curve of the flexible gear is determined by finding the coordinate origin and coordinate axis directions of the gear from the distance from the intersection of the center line of the tooth of the flexible gear and the curve of the wave generator to the end point of the major axis or minor axis of the curve of the wave generator, in accordance with the principle that the arc length does not change and the principle that the tooth symmetric center line of the flexible gear is perpendicular to the curve of the wave generator.

2. The flexible pin tooth wave reducer according to claim 1.

9. A radial undercut groove is provided between the pin tooth assembly and the internal gear body, thereby supporting both ends of the pin tooth and floating the center portion. By appropriately reducing and controlling the radial rigidity of the pin tooth, the load uniformity when the pin tooth assembly and multiple teeth of the flexible gear come into contact can be adjusted and controlled, thereby improving the load-bearing capacity and effectively preventing seizure.

2. The flexible pin tooth wave reducer according to claim 1.

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