TWM597834U - Harmonic speed-reduction device - Google Patents

Abstract

This creation is about a harmonic reducer, which includes a rigid inner gear ring, a flexible outer gear cup and a wave generator. The flexible outer gear cup is arranged in the rigid inner gear ring and is partially engaged with each other. The generator has a bearing set in the flexible outer gear cup, a cam ring set in the bearing and a coupling connecting the cam ring. The gap between the inner ring surface of the cam ring and the outer peripheral surface of the coupling Defined as G, there are multiple elastic elements between the inner ring surface of the cam ring and the outer peripheral surface of the coupling. The tensile elasticity of the elastic element is defined as K, 0.1≦K≦0.5, and the diameter of the elastic element is defined as D , The three satisfy the relationship of 0≦G≦KD. With the deformability of the elastic element, the structural wear of related parts can be reduced, so as to achieve the effect of automatic centering and improvement of operation accuracy.

Description

Harmonic reducer

This creation is related to the harmonic reducer, especially a harmonic reducer that can eliminate the running gap.

Harmonic reducer is a reduction gear with high reduction ratio. The conventional structure includes a rigid inner gear ring, a flexible outer gear cup arranged in the rigid inner gear ring, and a wave generator arranged in the flexible outer gear cup. When the coupling of the wave generator is driven by the power source, it will synchronously drive the elliptical wheel of the wave generator to rotate together, and then the flexible outer gear cup will be pushed up by the elliptical wheel and become an elliptical shape, making the rigid inner gear ring and The flexible external tooth cups can be completely engaged at the long axis of the elliptical wheel, and completely separated at the short axis of the elliptical wheel. Because there is a difference in the number of teeth between the rigid inner gear ring and the flexible outer gear cup, when the wave generator continues to rotate, this difference in the number of teeth can achieve the effect of a high reduction ratio, thereby generating a high torque output.

The harmonic reducer disclosed in the Republic of China Announcement No. I571573 patent is an adapter plate that assembles the coupling and the elliptical wheel together, in which there are two first convex portions and two opposite sides of the adapter plate. There are two second convex parts, and there are two first concave parts on the side of the elliptical wheel facing the adapter plate. As for the chassis part of the coupling, there are two second concave parts. Thereby, the elliptical wheel is clamped to the two first convex parts of the adapter plate through the two first concave parts, and the coupling is clamped to the two second convex parts of the adapter plate through the two second concave parts. In this way, the assembly between the coupling and the oval wheel is completed.

However, in the aforementioned patent documents, the gap between the corresponding concave and convex portions is likely to increase due to contact and wear. Once the gap increases, not only is it easy to generate operating noise, but also affect the service life. To solve the gap problem, the machining accuracy must be improved, but when the requirements for machining accuracy are relatively high, it will lead to an increase in manufacturing costs. Therefore, there is still room for improvement in the structure of the aforementioned patent documents.

In addition, the harmonic reducer disclosed in Japanese Patent Application Publication No. 2019-039547 has a spring and a ball between the input shaft and the elliptical wheel. When the input bearing is subjected to excessive torque, the elliptical wheel will slide relative to the input shaft. This avoids damage to related parts. However, since the input shaft is always in contact with the elliptical shaft and cannot absorb the eccentricity during operation, it does not have the function of automatic centering.

The main purpose of this creation is to provide a harmonic reducer, which can eliminate the running gap, reduce structural wear and improve operation accuracy.

In order to achieve the above main purpose, the harmonic reducer of this creation includes a rigid inner gear ring, a flexible outer gear cup, a wave generator, and a plurality of elastic elements. The flexible outer gear cup is arranged in the rigid inner gear ring and partially meshes with the rigid inner gear ring; the wave generator has a bearing, a cam ring and a coupling, and the bearing is arranged on the outer flexible ring In the gear cup, the cam ring is arranged in the bearing, and the inner ring surface of the cam ring has a plurality of first recesses, the coupling penetrates the cam ring, and the outer peripheral surface of the coupling has a plurality of The second recess; each elastic element is provided between the first recess of the cam ring and the second recess of the coupling, the gap between the inner ring surface of the cam ring and the outer peripheral surface of the coupling is defined as G, The tensile elasticity rate of the elastic element is defined as K, and the diameter of the elastic element is defined as D, and the three satisfy the following relationship: 0≦G≦KD, where 0.1≦K≦0.5.

It can be seen from the above that when the coupling is driven by the power source, it will drive the cam ring to rotate together, and then the flexible outer gear cup will be pushed by the cam ring to become an elliptical shape, so that the rigid inner gear ring and The flexible outer gear cup is completely engaged at the long shaft of the cam ring, and completely disengaged at the short shaft of the cam ring, so that continuous operation can produce high torque output. As for the operation process, due to the deformability of the elastic element, the cam ring reduces the structural wear of related parts, achieving the effect of automatic centering and improving operation accuracy.

Preferably, the Shore Durometer of each elastic element is between A60 and A90, for example, a polymer material containing polyurethane, rubber, unrestrained rubber, silicone rubber, or engineering plastic.

Preferably, each of the elastic elements may be composed of an elastic solid cylinder or a rigid solid cylinder covered with a layer of elastic material.

The detailed structure, characteristics, assembly or use of the harmonic reducer provided by this creation will be described in the detailed description of the subsequent implementation. However, those with ordinary knowledge in the field of creation should be able to understand that these detailed descriptions and specific embodiments listed in the implementation of this creation are only used to illustrate the creation, not to limit the scope of patent application for this creation.

The applicant first explains here that throughout the specification, including the following embodiments and claims in the scope of the patent application, the terms related to directionality are based on the directions in the drawings. Secondly, in the following embodiments and drawings, the same element numbers represent the same or similar elements or structural features.

1 to 3, the harmonic reducer 10 of the first embodiment of this creation includes a rigid inner gear ring 20, a flexible outer gear cup 30, a wave generator 40, and four elastic elements 50 ( The number of elastic elements 50 is not limited to four, and other numbers can also be used).

The flexible outer gear cup 30 is arranged in the rigid inner gear ring 20 and partially meshes with the rigid inner gear ring 20.

The wave generator 40 has a bearing 41, a cam ring 42 and a coupling 43. The bearing 41 is arranged in the flexible outer gear cup 30; the cam ring 42 is arranged in the bearing 41, and the inner ring surface 421 of the cam ring 42 has four first recesses 422; the coupling 43 has a disc 44 connected with one The shaft portion 45 of the disk portion 44, wherein the disk portion 44 is provided in the flexible outer gear cup 30 and is supported by the bearing 41. As for the shaft portion 45, the cam ring 42 and the two washers 46, 47 are inserted in sequence, and then A buckle 48 is used to assemble the cam ring 42 together so that the coupling 43 can drive the cam ring 42 to act together. In addition, the outer peripheral surface 451 of the shaft portion 45 has four second concave portions 452, The two recesses 452 correspond to the four first recesses 422 of the cam ring 42 in a one-to-one manner.

In this embodiment, each elastic element 50 is made of a material with a Shore Durometer between A60 and A90 (for example, a polymer material containing polyurethane, rubber, unrestrained rubber, silicone rubber, or engineering plastic). The made elastic solid cylinder makes each elastic element 50 have an anti-friction effect. As shown in Figures 2 and 4, four elastic elements 50 are provided in the four first recesses 422 of the cam ring 42 and the four second recesses 452 of the shaft portion 45 of the coupling 43 in a one-to-one manner. One end of the four elastic elements 50 is blocked by the disc 44 of the coupling 43, and the other end of the four elastic elements 50 is blocked by the spacer 47. In addition, as shown in Figure 5, there is a gap between the inner ring surface 421 of the cam ring 42 and the outer peripheral surface 451 of the shaft portion 45 of the coupling 43, which is defined as G, and the tensile elasticity of the elastic element 50 is defined as K , 0.1≦K≦0.5, the diameter of the elastic element 50 is defined as D, and the three satisfy the following relational expression: 0≦G≦KD. With the above relational expression, each elastic element 50 can indeed absorb the eccentricity generated during operation , And avoid excessive deformation of each elastic element to enter the gap G, so that the transmission effect between the cam ring 42 and the coupling 43 is reduced.

It can be seen from the above that when the shaft portion 45 of the coupling 43 is driven by the power source, it will drive the cam ring 42 to rotate together, and then the flexible outer gear cup 30 will be pushed by the cam ring 42 and become an elliptical shape, making the rigid inner The gear ring 20 and the flexible outer gear cup 30 are completely engaged at the long axis of the cam ring 42 and completely disengaged at the short axis of the cam ring 42. Such continuous operation can produce high torque output. As for the operation process, with the deformability of the four elastic elements 50, on the one hand, the gap G can be effectively eliminated to achieve the automatic centering function, and on the other hand, the gap between the cam ring 42 and the shaft 45 of the coupling 43 can be adjusted. The abrasion produced is corrected to achieve the purpose of improving the operation accuracy.

On the other hand, the structure of the elastic element can have various changes. As shown in Fig. 6, the elastic element 60 can also be made of a rigid solid cylinder 61 covered with a layer of elastic material 62. The rigid solid cylinder 61 can be made of a material such as metal. As for the elasticity The material of the material 62 is the same as the above-mentioned embodiment, so that the elastic material 62 has anti-friction characteristics. In this way, the elastic element 60 made by the combination of two different materials can also eliminate the gap, reduce the wear and improve the operation accuracy. effect.

10: Harmonic reducer 20: Rigid internal gear ring 30: Flexible external tooth cup 40: wave generator 41: Bearing 42: cam ring 421: inner ring surface 422: first recess 43 coupling 44: plate 45: Shaft 451: outer circumference 452: second recess 46: Gasket 47: Gasket 48: Buckle 50: elastic element G: gap D: The diameter of the elastic element 60: elastic element 61: rigid solid cylinder 62: Elastic material

Figure 1 is a perspective view of the harmonic reducer of the first embodiment of the creation. Figure 2 is a three-dimensional exploded view of the harmonic reducer of the first embodiment of the creation. Figure 3 is a cross-sectional view of Figure 1 taken along line 3-3. Fig. 4 is a plan view of the harmonic reducer according to the first embodiment of the creation with some components omitted. Fig. 5 is a partial enlarged view of Fig. 4. Fig. 6 is similar to Fig. 5, and mainly shows the elastic element provided by the harmonic reducer of the second embodiment of the invention.

42: cam ring

422: first recess

43: Coupling

44: plate

45: Shaft

452: second recess

50: elastic element

Claims (4)

A harmonic reducer, including: A rigid internal gear ring; A flexible outer gear cup arranged in the rigid inner gear ring and partially meshed with the rigid inner gear ring; A wave generator has a bearing, a cam ring and a coupling, the bearing is arranged in the flexible outer gear cup, the cam ring is arranged in the bearing, and the inner ring surface of the cam ring has a plurality of A first recess, the coupling is inserted through the cam ring, and the outer peripheral surface of the coupling has a plurality of second recesses; and A plurality of elastic elements are respectively arranged between one of the first recesses of the cam ring and one of the second recesses of the coupling, and the gap between the inner ring surface of the cam ring and the outer peripheral surface of the coupling Defined as G, the tensile modulus of the elastic element is defined as K, the diameter of the elastic element is defined as D, and the three satisfy the following relationship: 0≦G≦KD, where 0.1≦K≦0.5. The harmonic reducer according to claim 1, wherein the Shore Durometer of each elastic element is between A60 and A90. The harmonic reducer according to claim 1, wherein each of the elastic elements is an elastic solid cylinder. The harmonic reducer according to claim 1, wherein each of the elastic elements is made of a rigid solid cylinder covered with an elastic material.

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