CN107084194B

CN107084194B - Flexible bearing of harmonic reducer

Info

Publication number: CN107084194B
Application number: CN201710476134.4A
Authority: CN
Inventors: 苏达士
Original assignee: Ningbo Cixing Bearing Co Ltd
Current assignee: Ningbo Cixing Bearing Co Ltd
Priority date: 2017-06-21
Filing date: 2017-06-21
Publication date: 2022-12-13
Anticipated expiration: 2037-06-21
Also published as: CN107084194A

Abstract

The utility model provides a harmonic speed reducer ware flexible bearing, includes flexible bearing's inside and outside circle, arranges the steel ball in the holder in, flexible bearing's outer lane internal surface is the stairstepping, and the left and right side of outer lane internal surface internal diameter is different, and the radius difference on the left and right side of outer lane internal surface internal diameter is h. After the flexible bearing in the harmonic reducer is installed in a flexible gear, certain inclination and warping deformation can be generated due to uneven load. The inner surface and the inner hole of the outer ring of the flexible bearing have different inner diameters on the left side and the right side, the radial rigidity is different, and the bearing capacity of the outer ring is different, so that the same radial deformation is generated.

Description

Flexible bearing of harmonic reducer

Technical Field

The invention relates to a bearing with a special structure, in particular to a flexible bearing of a harmonic reducer, which is used on a robot.

Background

The harmonic reducer is an advanced and precise reducer, and is widely applied to the field of robot precise machinery due to the advantages of small volume, light weight, small return difference, high transmission efficiency, easiness in realizing precise position control and the like. With the rise of intelligent manufacturing with industrial robots and the like as the core, robots with various purposes are used in various fields required by human beings, and flexible bearings and flexible gears are key parts and wearing parts in harmonic reducers and often have precision failure and fatigue failure before other parts.

Because the flexible gear is a thin-wall cylinder structure, after the flexible gear is installed in the flexible bearing, the outer ring of the bearing and the flexible gear are in interference fit, a small amount of deformation is often generated during working, the flexible bearing is less worn at one side of an opening of the flexible gear after long-term working, the other side of the flexible bearing is more worn, and the transmission precision can be reduced at the place with large wear, so that the precision, the transmission efficiency and the service life of the flexible gear, the flexible bearing and even the whole harmonic reducer are reduced, and the problem to be solved urgently is solved.

The patent No. CN201510793044.9 'harmonic reducer with elastic washer between flexible bearing and flexible gear', provides a harmonic reducer which can effectively reduce the abrasion of the inner surface of flexible gear and the outer surface of flexible bearing outer ring due to interference fit, is beneficial to vibration reduction and assembly, thereby improving the service life of the harmonic reducer.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the flexible bearing of the harmonic reducer is high in bearing capacity and flexibility and matched with a flexible gear on the harmonic reducer, and the problems of fatigue damage and precision deterioration of the flexible bearing due to uneven outer ring abrasion are solved for a long time, so that the transmission precision, the transmission efficiency and the service life of the flexible bearing and the harmonic reducer are greatly improved.

The technical scheme adopted by the invention for solving the problems is as follows: the utility model provides a harmonic speed reducer ware flexible bearing, includes flexible bearing inner and outer lane, arranges the steel ball in the holder in, flexible bearing's outer lane internal surface is the stairstepping, and outer lane internal surface internal diameter left and right is different, and the radius difference on the left and right of outer lane internal surface internal diameter is h.

Compared with the prior art, the invention has the advantages that: because the outer rings of a plurality of deep groove ball bearings are subjected to different loads on the left side and the right side, certain inclination or buckling deformation is generated due to uneven loads. The compliant bearings in the harmonic reducer will have some tilt due to uneven loading after being installed into the flexspline, as shown in fig. 3. The inner surface and the inner hole of the flexible bearing outer ring have different inner diameters on the left side and the right side. The flexible bearing with the special structure can reduce the inclination and the warping deformation caused by uneven load, thereby solving the long-term phenomenon of uneven abrasion of the outer ring of the flexible bearing, namely solving and prolonging the transmission precision and the transmission service life of the flexible bearing and greatly prolonging the service life of the harmonic reducer.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2, a reference diagram of the use state of the present invention.

Figure 3, flexspline opening results in uneven stress on the compliant bearing (prior art).

Detailed Description

Embodiments of the present invention are further described below with reference to the accompanying drawings.

The flexible bearing is a special rolling bearing, the bearing width is narrow, the wall thickness of the outer ring 1 is thin, the inner ring 6 is forced to deform, the flexible gear 7 is a thin-wall cylinder, the outer ring 1 and the flexible gear 7 of the flexible bearing are arranged in the flexible gear in an interference fit mode, and the bearing and the flexible gear can often generate a small amount of deformation after work, as shown in fig. 3.

The flexible bearing mainly has less abrasion on one side of an opening of the flexible gear 7, the other side of the opening of the flexible gear is more abraded, the structure of the flexible bearing is improved and optimized according to the characteristic, the structure of an inner surface inner hole of the outer ring 1 is changed, the inner surface inner diameters of the left side 2 and the right side 3 are different and are asymmetric in stepped shape, and the radial rigidity is different because the inner diameters of the left side and the right side are different, so that the outer ring can generate the same deformation when being subjected to different left and right loads.

If the right side 3 of the side with a small inner diameter of the inner surface has larger rigidity and can resist larger radial load, the deformation (namely the diameter reduction) generated by the right side 3 is almost the same as that of the left side 2, as shown in figure 1, so that the inclined and warped deformation state shown in figure 3 is relieved or completely solved, namely the conditions of different abrasion of the right side 2 and the left side 3 are relieved or solved, and the transmission precision, the transmission efficiency and the service life of the flexible bearing and the flexible wheel are prolonged, as shown in figure 2.

The radius difference of the left and

right sides

2 and 3 of the inner surface inner diameter of the bearing outer ring 1 is h, and is determined according to the design of bearings with different sizes.

0.4B > h 0.02B, B is the width of the flexible bearing outer ring 1, the cage 4 should be installed on the side where the inner diameter of the bearing outer ring is larger, and the steel balls 5 are placed in the cage 4.

When the flexible bearing is used, the left side 2 with the larger inner diameter of the outer ring 1 in the flexible bearing is in the same direction with the opening side of the flexible gear 7, and the other flexible bearings are installed in the same way as the flexible bearing, namely the outer ring 1 of the flexible bearing is in interference fit with the inner surface of the flexible gear 7, as shown in fig. 2. In the figure, the side wall thickness of the opening part close to the flexible gear 7 is thinner, the load of the outer ring is smaller, and the wall thickness of the outer ring close to the closed end of the flexible gear is thicker than that of the outer ring which is slightly larger than the load, so that the radial changes of the two sides of the outer ring of the bearing are equal, the inclination condition of the outer ring is obviously improved, and the aim of reducing the uneven wear condition of the outer ring is fulfilled.

Claims

1. The utility model provides a harmonic speed reducer ware flexible bearing, includes flexible bearing inside and outside circle (6, 1), arranges steel ball (5) in holder (4) in, its characterized in that flexible bearing's outer lane (1) internal surface is the stairstepping, and the outer lane internal surface internal diameter is left and right (2, 3) different, and the radius difference on the outer lane internal surface internal diameter left and right (2, 3) is h.

2. A harmonic reducer compliant bearing according to claim 1 characterised in that the difference in radius between the left and right sides (2, 3) of the inner surface internal diameter of the outer ring is h,0.4b > h >0.02b, b being the width of the compliant bearing outer ring (1).