Flexspline and harmonic reducer equipped with same

Abstract

A flexspline (1) and a harmonic reducer including the same, wherein the flexspline (1) has a flexspline body (11) configured as a cylindrical structure, a first end of the flexspline body (11) is a tooth portion (12), a plurality of external teeth (121) are formed on the outer wall of the tooth portion (12) along its circumferential direction, and a reinforcing structure is provided between two adjacent external teeth (121), and the reinforcing structure includes a plurality of arc segments to increase the thickness of the portion between the two external teeth (121).

Description

[Technical field]

[0001] This application claims priority to a Chinese patent application filed on February 22, 2021, bearing application number 202110202751.1 and entitled "Flexspline and harmonic reducer equipped therewith," the entire text of which is incorporated herein by reference.

[0002] The present application relates to the technical field of harmonic reducers, and in particular to a flexspline and a harmonic reducer including the same. [Background technology]

[0003] With the model change and upgrade of intelligent manufacturing, the high-precision transmission of harmonic reducers in industrial robots has higher requirements for accuracy and reliability. As one of the core components of robot transmission, the harmonic reducer has a small volume, a large reduction ratio, a large number of meshing teeth, smooth transmission, high load force, high transmission accuracy and other characteristics compared with other reducers, so it is widely used in space, military, industrial robots and other fields. At present, the main problem that restricts the development of the harmonic reducer industry is the problem of life, and the breakage of the tooth root of the flexspline and the tearing of the flange are the main causes of the failure of the harmonic reducer. In addition, when the tooth profile of the flexspline and the dimensions of the flange structure are changed, both of these damages always occur.

[0004] Although the industry has implemented specialized structural designs for tooth structures, cylinder and flange R-angle connections, etc., the flexspline remains the weakest part of the harmonic reducer. Some harmonic reducers have implemented specialized structural designs for the curvature radius R of the bend, but the breakage of the flexspline tooth root cannot be solved. Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above, the present application provides a flexspline and a harmonic reducer including the same, which are used to solve at least the technical problem that the tooth root portion of the flexspline present in the conventional technology is easily broken. [Means for solving the problem]

[0006] In a first aspect, the present application provides a method for producing a method for manufacturing a pharmaceutical composition comprising: A flexspline body configured as a cylindrical structure, one end of the flexspline body forms a toothed portion, a plurality of external teeth are formed on an outer wall of the toothed portion along a circumferential direction thereof, and a reinforcing structure is provided between two adjacent external teeth, The flexspline includes a reinforcing structure that includes a plurality of arc segments to increase the thickness of a portion between two of the external teeth.

[0007] More preferably, the reinforcing structure includes a convex arc and an outer transition arc; the convex arcs are provided between every two of the external teeth and protrude from an outer circumferential surface of the flexspline body, The outer transition arcs are provided on both sides of the convex arc, forming a smooth curved surface between the convex arc and the two external teeth.

[0008] More preferably, the flexspline body has a first end and a second end, the tooth portion is provided at the first end of the flexspline body, and a flange portion is provided at the second end of the flexspline body, The flange portion has an annular structure and is connected to the second end of the flexspline body via an annular flange wall.

[0009] More preferably, the thickness at the location of the outer transition arc is L1, and the thickness of the flange wall is L2; The value of L1 is 1.5 to 1.8 times the value of L2.

[0010] More preferably, the radius of the outer transition arc is R1, and the radius of the arc at the end of the meshing portion of the external teeth is R2; R1 <R2である。

[0011] More preferably, the center of the convex arc, the root circle of the external tooth, and the center of the flexspline body are on the same straight line.

[0012] More preferably, the radius of the convex arc is R0 and R1 <R2<R0である。

[0013] In a second aspect, the present application provides a method for producing a method for manufacturing a pharmaceutical composition comprising: a circular spline having a ring structure and a plurality of internal teeth formed on an inner wall along a circumferential direction; and the flexspline into which the circular spline is fitted, the internal teeth meshing with the external teeth, and the number of the internal teeth being greater than the number of the external teeth.

[0014] More preferably, the tip of the internal tooth is provided with an inner circular arc and an inner transition circular arc, The two inner transition arcs are provided, and the two inner transition arcs are provided on both sides of the inner arc, respectively; The inner arc corresponds in position to the convex arc, and the inner transition arc corresponds in position to the outer transition arc.

[0015] More preferably, the radius of the inner circular arc is equal to or greater than the radius of the convex circular arc, and / or The radius of the inner transition arc is greater than or equal to the radius of the outer transition arc. Effect of the Invention

[0016] In the present application, a reinforcing structure is provided between two external teeth of the flexspline, i.e., at the position where the thickness is smallest, to increase the thickness at that position, specifically, a structure is designed in which three arcs protrude and transition smoothly, optimizing the thinnest position of the tooth portion and increasing the thickness of the tooth root portion, improving the load strength of the tooth portion of the harmonic flexspline, thereby extending the life of the harmonic reducer. In the present application, the strength of the tooth portion of the flexspline can be improved to extend the life of the flexspline, thereby extending the life of the harmonic reducer and improving its reliability.

[0017] The above and other objects, features, and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the drawings. The drawings described below are merely some embodiments of the present disclosure, and those skilled in the art can obtain other drawings from these drawings without creative efforts. [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic diagram showing the structure of a flexspline according to the present invention; [Diagram 2] 1 shows a schematic cross-sectional view of a flexspline according to the present application. [Diagram 3] 1 is a schematic diagram showing the structure of some external teeth of the flexspline of the present application; [Figure 4] A partially enlarged view of the external teeth is shown. [Diagram 5] 1 shows a schematic diagram of the structure of a circular spline of the present application. [Figure 6] A schematic diagram of the structure of some of the internal teeth is shown. [Figure 7] A schematic diagram of the internal and external teeth meshing is shown. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application, but it is obvious that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without any creative efforts belong to the scope of protection of the present application.

[0020] The terms used in the examples of this application are used only for the purpose of describing specific examples, and are not intended to limit the present application. The singular forms "a," "the," and "the" used in the examples of this application and the appended claims are intended to include the plural forms unless otherwise clearly indicated by the context, and "plurality" generally includes at least two, but does not exclude the case of including at least one.

[0021] It should be understood that the term "and / or" used herein is merely a description of the relation between related objects, and means that three relations can exist, for example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Also, the sign " / " in this specification generally indicates that the relation before and after is an "or" relation.

[0022] It should be noted that the terms "comprise," "include," or any other variation thereof are intended to cover a non-exclusive inclusion, whereby a product or system that includes a set of elements includes not only those elements, but also other elements not expressly listed or that are inherent to such product or system. In the absence of further limitations, an element qualified by the words "comprises a" does not exclude the presence of other identical elements in the product or system that includes said element.

[0023] In the present application, a reinforcing structure is provided between two external teeth of the flexspline, i.e., at the position where the thickness is smallest, to increase the thickness at that position, specifically, a structure is designed in which three arcs are raised and smoothly transition, optimizing the thinnest position of the tooth portion, increasing the thickness of the tooth root portion, improving the load strength of the tooth portion of the harmonic flexspline, and thereby extending the life of the harmonic reducer. A structural design is adopted for the circular spline in which three concave arcs facing the flexspline smoothly transition, ensuring that no interference occurs when the circular spline meshes with the flexspline. In addition, the concave tooth socket serves as an oil storage portion, ensuring more sufficient lubrication at the meshing portion between the circular spline and the flexspline. The present application will be described in detail below with reference to specific examples.

[0024] As shown in Figs. 1 and 2, the present application The flexspline body 11 is configured as a cylindrical structure, A first end of the flexspline body 11 becomes a toothed portion 12, and a plurality of external teeth are formed on the outer wall of the toothed portion 12 along the circumferential direction. 121 are formed, and two adjacent external teeth 121 A reinforcing structure is provided between the As shown in Figures 3 and 4, the reinforcing structure is made up of two external teeth. 121 The present invention provides a flexspline 1 including a plurality of arc segments for increasing the thickness of the portion between the arc segments.

[0025] Specifically, the reinforcing structure includes a convex arc 122 and an outer transition arc 123, and the convex arc 122 is formed by two outer teeth. 121 The flexspline body 11 is provided at the center position of the flexspline 11, and protrudes along the radial direction of the flexspline body 11. 121 The thickness of the portion between the convex arc 122 and the outer teeth 123 is increased, and two outer transition arcs 123 are provided, and the two outer transition arcs 123 are provided on both sides of the convex arc 122, thus forming a three-arc structure, and the convex arc 122 and the two outer teeth 123 form a three-arc structure. 121 A smooth curved surface is formed between the two, thereby avoiding stress concentration.

[0026] A flange portion 13 is provided at a second end of the flexspline body 11, and the flange portion 13 has an annular structure and is connected to the second end of the flexspline body 11 via an annular flange wall 131. The flange wall 131 has a thickness along the axial direction of the flexspline body 11 of L2, and a thickness at the location of the outer transition arc 123 of L1, i.e., the thickness of the thinnest portion of the tooth portion 12 is L1, where in one specific embodiment, the value of L1 is 1.5 to 1.8 times the value of L2, the tooth root of the flexspline 1 is close to the meshing portion, and the upper end has an open structure, while the flange wall 131 applies a radial rotational force changed from the axial rotational force, and the force reception is complex. Since the flange portion 13 plays a role in connecting the flexspline body 11 and the flange portion 13 to transmit torque, usually, the thickness L2 of the flange wall 131 is first determined, and then the thickness L1 of the tooth root is increased as much as possible while ensuring the performance of the harmonic reducer in accordance with the above-mentioned limiting relationship, thereby extending the life of the flexspline 1. According to the above structural limitations, the life of the tooth root and the flange can be extended while ensuring that the external teeth can flexibly deform reasonably.

[0027] The convex arc 122 has a radius R0 and a center 121It is on the connecting line between the root circle of the [tooth] and the center of the center circle of the flex spline 1. Both ends of the outer transition arc 123 are connected to the external tooth meshing part. By using the convex arc 122, the thickness at the root significantly increases. However, with such a design, if the thinnest part at the root changes from the center to the connection parts on both sides and the smoothness of the connection is insufficient, stress concentration will occur. The radius of the outer transition arc 123 is R1, the arc radius at the end of the external tooth meshing part is R2, and R1 < R2 < R0. In this embodiment, the convex arc 122 and the external tooth meshing part are connected by the outer transition arc 123. Due to the structural characteristics of the outer transition arc 123, the relationship between its radius R1 and the arc radius R2 at the end of the external tooth meshing part is R1 < R2. Also, when different R1 values are selected for the transition arc, the thinnest positions on both sides will change accordingly. The larger the R1 value, the thicker the thinnest positions on both sides will be accordingly. Therefore, in order to make the thickness of the root part of the present application as large as possible, it is preferable that the R1 value is large.

[0028] As shown in FIG. 5, the present application is configured as a ring structure, and includes a circular spline 2 in which a plurality of internal teeth 21 are formed in the circumferential direction on the inner wall, and the circular spline 2 is fitted, and the internal teeth 21 mesh with the external teeth 121 and the number of internal teeth 21 is more than the number of external teeth 121 of the above-mentioned flex spline 1. The present application further provides a harmonic reducer including the same.

[0029] As shown in FIGS. 6 and 7, preferably, an inner arc 22 and inner transition arcs 23 are provided at the tooth tips of the internal teeth 21. Two inner transition arcs 23 are provided, and the two inner transition arcs 23 are respectively provided on both sides of the inner arc 22. The inner arc 22 corresponds in position to the convex arc 122, and the inner transition arcs 23 correspond in position to the outer transition arcs 123. Thereby, it is ensured that no interference occurs when the circular spline 2 meshes with the flex spline 1. Also, an oil storage part capable of accommodating a predetermined amount of lubricating oil is formed on the inner arc 22, and sufficient lubrication at the meshing part between the circular spline 2 and the flex spline 1 is ensured.

[0030] As shown in FIG. 7, the tip of the internal tooth 21 has excellent rigidity and is not a direct meshing portion, but a concave arc of the tip of the internal tooth 21. radius If is made equal to or greater than the radius of the convex arc 122 of the flexspline 1, the relief portion becomes large and the radii of the transition arcs on both sides also become larger than the transition arc R1 of the flexspline 1, thereby ensuring sufficient relief space and lubricant storage space.

[0031] When the flexspline 1 comes into contact with the long axis of the hollow shaft, the teeth 12 of the flexspline 1 mesh with the internal teeth 21 of the circular spline 2, and in this case, the external teeth 121 The tooth root of the inner tooth 21 and the tooth tip of the inner tooth 21 have a sufficient relief portion, and an oil storage space is formed.

[0032] According to the structural features of the harmonic reducer and the flexspline itself, in this application, a new tooth root structure of the flexspline is designed, and the tooth tip structure of the circular spline 2 is also optimized, which can effectively improve the breakage of the tooth root of the flexspline in the prior art, improve the operating stability of the harmonic reducer, and extend its service life.

[0033] Although the above specifically shows and describes exemplary embodiments of the present disclosure, it is to be understood that the present disclosure is not limited to the detailed construction, arrangement, and implementation described herein, but rather, the present disclosure is intended to include various modifications and equivalents included within the spirit and scope of the appended claims. [Explanation of symbols]

[0034] 1. Flexspline 11. Flexspline body 12. Teeth 121, outer teeth 122, convex arc 123, outer transition arc 13. Flange section 131, flange wall 2. Circular spline 21. Inner teeth 22. Inner arc 23. Inner transition arc

Claims

1. A harmonic reducer, a circular spline having a ring structure and a plurality of internal teeth formed on an inner wall along a circumferential direction; A flexspline, A flexspline body configured as a cylindrical structure, one end of the flexspline body forms a toothed portion, a plurality of external teeth are formed on an outer wall of the toothed portion along a circumferential direction thereof, and a reinforcing structure is provided between two adjacent external teeth of the plurality of external teeth, the reinforcing structure includes a plurality of arc segments for increasing a thickness of a portion between two of the external teeth; the reinforcing structure includes a convex arc, the convex arc is provided between every two of the external teeth and protrudes from an outer circumferential surface of the flexspline body, and a center of the convex arc, a root circle of the external tooth, and a center of the flexspline body are on the same straight line, The reinforcing structure includes an outer transition arc, the outer transition arc is provided on both sides of the convex arc, and forms a smooth curved surface between the convex arc and the two external teeth; the flexspline body has a first end and a second end, the tooth portion is provided at the first end of the flexspline body, and a flange portion is provided at the second end of the flexspline body, the flange portion having an annular structure and connected to the second end of the flexspline body via an annular flange wall; the thickness of the flexspline body at the location of the outer transition arc is L1, the thickness of the flange wall is L2, and the value of L1 is 1.5 to 1.8 times the value of L2; The radius of the outer transition arc is R1, the radius of the arc at the end of the meshing portion of the external teeth is R2, and the radius of the convex arc is R0, where R1<R2<R0; the circular spline is fitted into the flexspline, the internal teeth are engaged with the external teeth, and the number of the internal teeth is greater than the number of the external teeth; The tip of the internal tooth is provided with an inner arc and two inner transition arcs; the two inner transition arcs are provided on either side of the inner arc, The harmonic reducer according to the present invention, characterized in that the inner arc corresponds in position to the convex arc, and the inner transition arc corresponds in position to the outer transition arc.

2. the radius of the inner circular arc is greater than or equal to the radius of the convex circular arc; and / or 2. The harmonic reducer according to claim 1, wherein a radius of the inner transition arc is equal to or greater than a radius of the outer transition arc.

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