CN-115559996-B - Flexible bearing, wave generator, harmonic reducer and transmission device

CN115559996BCN 115559996 BCN115559996 BCN 115559996BCN-115559996-B

Abstract

The application relates to a flexible bearing, a wave generator, a harmonic reducer and a transmission device, wherein the retainer comprises a flexible inner ring and a flexible outer ring which are coaxially arranged, the flexible inner ring and the flexible outer ring are respectively arranged on the periphery of a cam in an elliptical structure, the retainer is arranged between the flexible inner ring and the flexible outer ring and comprises an annular body, a plurality of guide pockets which are distributed at intervals are arranged in the circumferential direction of the annular body, and a plurality of rolling elements are rotatably arranged in the guide pockets, wherein the density of the guide pockets at the two ends of the long axis of the flexible inner ring and the flexible outer ring is greater than that of the guide pockets at the two ends of the short axis of the flexible inner ring and the flexible outer ring. The guide pockets are more near the long axis, so that more rolling elements are arranged near the long axis, less rolling elements are arranged near the short axis, the rolling elements near the short axis are sparse, and under the condition of the same load, the contact stress of a single rolling element is reduced, so that the service life of the whole machine is prolonged.

Inventors

ZHANG HAO
GU JIAJIA
CAI DACHENG

Assignees

珠海格力电器股份有限公司

Dates

Publication Date: 20260508
Application Date: 20221019

Claims (9)

1. A wave generator is characterized by comprising a flexible bearing and a cam; the compliant bearing includes: the flexible inner ring and the flexible outer ring are coaxially arranged and are respectively arranged on the periphery of the cam in an elliptical structure; a retainer arranged between the flexible inner ring and the flexible outer ring, the retainer comprising an annular body provided with a plurality of guide pockets distributed at intervals in the circumferential direction, and A plurality of rolling elements rotatably disposed within the guide pockets, wherein the density of the guide pockets at both ends of a major axis of the flexible inner race and the flexible outer race is greater than the density of the guide pockets at both ends of a minor axis of the flexible inner race and the flexible outer race; the cam is provided with an oval outer peripheral surface and is connected with the flexible inner ring, and the cam rotates to drive the flexible bearing to synchronously rotate and enable the flexible bearing to be in an oval structure; the retainer is fixedly connected with the cam.
2. The wave generator of claim 1, wherein the annular body comprises a first arcuate segment, a second arcuate segment, a third arcuate segment, and a fourth arcuate segment that are sequentially and continuously distributed along a circumferential direction; The two ends of the long shaft of the flexible inner ring and the flexible outer ring respectively fall into the first arc-shaped section and the third arc-shaped section, and the two ends of the short shaft of the flexible inner ring and the flexible outer ring respectively fall into the second arc-shaped section and the fourth arc-shaped section; The guide pocket of any one of the first and third arcuate segments has a density greater than the guide pocket of any one of the second and fourth arcuate segments.
3. The wave generator of claim 2, wherein the density of the guide pockets in the first arcuate segment and the density of the guide pockets in the third arcuate segment are the same and/or the density of the guide pockets in the second arcuate segment and the density of the guide pockets in the fourth arcuate segment are the same.
4. The wave generator of claim 2, wherein the central angles of the first, second, third and fourth arcuate segments are all the same.
5. The wave generator of claim 2, wherein a plurality of the guide pockets within any of the first, second, third, and fourth arcuate segments are equally spaced apart.
6. The wave generator according to claim 2, wherein five guide pockets are provided in the first and third arcuate sections, respectively, and/or two guide pockets are provided in the second and fourth arcuate sections, respectively.
7. The wave generator of claim 1, wherein the rolling elements are balls.
8. A harmonic reducer, characterized by comprising: a rigid annular body having a plurality of rigid internal teeth; A flexible annular body rotatably disposed within the rigid annular body, the flexible annular body having a plurality of flexible external teeth, the plurality of rigid internal teeth being greater in number than the plurality of flexible external teeth and a portion of the rigid internal teeth intermeshed with a portion of the flexible external teeth, and The wave generator of any one of claims 1-7 rotatably disposed within the flexible annular body inner race such that the flexible annular body is elliptically configured and rotates relative to the wave generator at a differential speed.
9. A kind of transmission device, which is used for the transmission of electric power, characterized by comprising the following steps: motor and load part, and A harmonic reducer as claimed in claim 8 wherein the output of the motor is connected to the cam and the load member is connected to the flexible annular body.

Description

Flexible bearing, wave generator, harmonic reducer and transmission device Technical Field The application relates to the technical field of speed reducers, in particular to a flexible bearing, a wave generator, a harmonic speed reducer and a transmission device. Background The harmonic reducer mainly comprises a rigid annular body, a flexible annular body and a wave generator. The flexible ring body generates elastic deformation under the action of the wave generator, and the flexible teeth on the flexible ring body interact with the rigid wheel, so that the transmission purpose is achieved. The flexible gear which is deflected into an elliptical shape is meshed with steel teeth of the rigid annular body at both end portions of the long axis thereof, and torque is transmitted. The wave generator is provided with a cam with an oval outer peripheral surface and a flexible bearing arranged on the oval outer peripheral surface of the cam, the flexible inner ring and the flexible outer ring of the flexible bearing are oval through cam deflection, a plurality of rolling elements are arranged between the flexible inner ring and the flexible outer ring, a retainer is arranged between the flexible inner ring and the flexible outer ring, a plurality of guide pockets are arranged at equal intervals along the circumferential direction of the retainer and used for wrapping the rolling elements, and the rolling elements are isolated from being contacted with each other. Because the flexible external teeth and the rigid internal teeth are meshed at the two ends of the long shaft of the wave generator, the rolling elements near the two ends of the long shaft are stressed to cause the contact stress to be increased, and the balls near the short shaft are not stressed and are in a loose state, so that the problems that the rolling elements at the two ends of the long shaft are larger in stress and unbalanced in stress and the service life of the whole machine is reduced are caused. Disclosure of Invention The application aims to provide a flexible bearing, a wave generator, a harmonic reducer and a transmission device, which can reduce the contact stress of rolling elements at two ends of a long shaft, and the stress of each rolling element is uniform, so that the service lives of the rolling elements, a roller path and the like are prolonged, and the service life of the whole machine is correspondingly prolonged. To this end, in a first aspect, an embodiment of the present application provides a flexible bearing, including a flexible inner ring and a flexible outer ring coaxially disposed, where the flexible inner ring and the flexible outer ring are disposed on an outer circumference of a cam in an elliptical structure, a retainer disposed between the flexible inner ring and the flexible outer ring, the retainer including an annular body, a plurality of guide pockets disposed in a circumferential direction of the annular body and spaced apart from each other, and a plurality of rolling elements rotatably disposed in the guide pockets, where densities of the guide pockets at both ends of long axes of the flexible inner ring and the flexible outer ring are greater than densities of the guide pockets at both ends of short axes of the flexible inner ring and the flexible outer ring. In one embodiment of the application, the annular body comprises a first arc-shaped section, a second arc-shaped section, a third arc-shaped section and a fourth arc-shaped section which are sequentially and continuously distributed along the circumferential direction, wherein the two ends of the long axis of the flexible inner ring and the long axis of the flexible outer ring respectively fall on the first arc-shaped section and the third arc-shaped section, the two ends of the short axis of the flexible inner ring and the short axis of the flexible outer ring respectively fall on the second arc-shaped section and the fourth arc-shaped section, and the density of the guide pocket of any one of the first arc-shaped section and the third arc-shaped section is larger than the density of the guide pocket of any one of the second arc-shaped section and the fourth arc-shaped section. In one embodiment of the application, the density of the guide pockets in the first arcuate segment is the same as the density of the guide pockets in the third arcuate segment, and/or the density of the guide pockets in the second arcuate segment is the same as the density of the guide pockets in the fourth arcuate segment. In one embodiment of the present application, central angles of the first arc-shaped section, the second arc-shaped section, the third arc-shaped section and the fourth arc-shaped section are all the same. In one embodiment of the present application, the plurality of guide pockets in any one of the first, second, third and fourth arcuate segments are equally spaced apart. In one embodiment of the application, five guide pockets are respectively arrang