CN113898712A

CN113898712A - Harmonic speed reducer

Info

Publication number: CN113898712A
Application number: CN202111173326.0A
Authority: CN
Inventors: 吴松涛; 黄海波
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-10-08
Filing date: 2021-10-08
Publication date: 2022-01-07

Abstract

The invention discloses a harmonic speed reducer, which relates to the technical field of harmonic speed reducers and comprises a flexible gear with an outer gear ring and a wave generator, wherein the wave generator is rotatably arranged at the inner side of the flexible gear, the outer contour of the wave generator is composed of four arc surfaces, and two adjacent arc surfaces are tangent. The outer contour of the wave generator is composed of tangent arc surfaces, when the wave generator rotates, the wave generator extrudes the flexible gear to deform, the part of the flexible gear, which is meshed with the steel wheel, is provided with an arc with the same curvature as that of the wave generator, so that the flexible gear and the steel wheel are meshed, meshed and separated, and the stress distribution is better when the flexible gear is meshed with the steel wheel. The outer gear ring of the flexible gear of the harmonic reducer is well meshed with the rigid inner gear ring at the contact section, the shaking caused by poor gear meshing in the transmission process can be completely eliminated, and the service life of the flexible gear is greatly prolonged.

Description

Harmonic speed reducer

Technical Field

The invention relates to the technical field of harmonic reducers, in particular to a harmonic reducer.

Background

The harmonic reducer is a novel reducer developed by using the transmission principle of transmitting motion and power by utilizing controllable elastic deformation of a flexible element, and has the advantages of high bearing capacity, large transmission ratio, small volume, light weight, stable transmission, no impact, no noise, high motion precision and the like, so that the harmonic reducer is widely applied to the industries of aerospace, shipbuilding, robots, machine tools and the like, and particularly shows superiority by adopting harmonic gear transmission in a servo system with high dynamic performance.

In the current market, the outline of the waveform generator of the domestic harmonic reducer is designed in an oval shape (see figure II), the gear base circle of the flexible gear and the steel wheel is round, and the gear is machined in a round shape. After the flexible gear is installed on the elliptical wave generator, the gear tooth shape on the flexible gear is inevitably deformed, so that the flexible outer gear ring (flexible gear) of the harmonic speed reducer is not well meshed with the rigid inner gear ring (rigid gear), the harmonic speed reducer is easy to shake in the gear transmission process, the phenomena of tooth surface abrasion and metal fatigue are accelerated, the repeated positioning precision of equipment (such as a robot) is reduced, the transmission strength of the flexible gear is reduced and the like, and under the condition that the external load is increased, the flexible gear is easily subjected to wrinkle deformation and even is torn and damaged. The service life of the harmonic speed reducer is greatly reduced, and the damage of the flexible gear can cause the integral scrapping of the harmonic speed reducer due to the high manufacturing cost of the harmonic speed reducer.

Disclosure of Invention

Therefore, the invention provides a harmonic speed reducer, which aims to solve the problem that the flexible gear and the rigid wheel are not well meshed due to the fact that the outline of a waveform generator in the prior art adopts an oval outline and the gear base circles of the flexible gear and the steel wheel are circular.

In order to achieve the above purpose, the invention provides the following technical scheme:

a harmonic speed reducer comprises a flexible gear with an outer gear ring and a wave generator, wherein the wave generator is rotatably arranged on the inner side of the flexible gear, the outer contour of the wave generator is composed of four arc surfaces, and two adjacent arc surfaces are tangent.

Further, the first arc surface and the second arc surface are arcs with two equal radiuses, the third arc surface and the fourth arc surface are arcs with two equal radiuses, and the radiuses of the first arc surface and the second arc surface are smaller than the radiuses of the third arc surface and the fourth arc surface.

Further, the first arc surface and the second arc surface are two arcs with unequal radiuses, and the third arc surface and the fourth arc surface are two arcs with unequal radiuses.

A harmonic speed reducer comprises a flexible gear and a wave generator, wherein the wave generator is rotatably arranged on the inner side of the flexible gear, the outer contour of the wave generator is composed of at least five arc surfaces, and two adjacent arc surfaces are tangent.

Further, the harmonic reducer machine also comprises a flexible bearing, and the flexible bearing is arranged between the wave generator and the flexible gear.

Furthermore, the harmonic reducer also comprises a rigid gear with an inner gear ring, the rigid gear is arranged on the outer side of the flexible gear, and part of gears of the inner gear ring and part of gears of the outer gear ring are meshed with each other.

The invention has the following advantages: the outer contour of the wave generator is composed of tangent arc surfaces, when the wave generator rotates, the wave generator extrudes the flexible gear to deform, the reference circle of two parts at the upper and lower meshing positions of the outer gear on the flexible gear and the inner gear on the rigid gear and the wave generator are ensured to have arcs with the same curvature, so that the flexible gear and the rigid gear are meshed in, meshed and meshed out, and the stress distribution is better when the flexible gear is meshed with the rigid gear. The outer gear ring of the flexible gear of the harmonic speed reducer is well meshed with the rigid inner gear ring at the contact section, the shaking caused by poor gear meshing in the transmission process can be completely eliminated, the positioning precision of equipment is obviously improved, the gear meshing matching is good, gear abrasion or other gear mechanical damage is eliminated, the phenomena of fatigue pitting corrosion and the like of the gear are reduced, the metal fatigue abrasion is greatly reduced, the tooth root fracture condition of the flexible gear is avoided, and the service life of the flexible gear is greatly prolonged.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art can understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the functions and purposes of the present invention, should still fall within the scope covered by the contents disclosed in the present invention.

Fig. 1 is a schematic structural diagram of a harmonic reducer according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an outer contour of a wave generator of a harmonic reducer provided in embodiment 1 of the present invention;

fig. 3 is a schematic structural diagram of an outer contour of a wave generator of a harmonic reducer provided in embodiment 2 of the present invention.

In the figure: 1-a wave generator; 2-a flexible gear; 3-a compliant bearing; 4-a rigid gear; 11-a first arc surface; 12-a second arc surface; 13-a third arc surface; 14-fourth arc surface.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present specification, the terms "upper", "lower", "left", "right", "middle", and the like are used for clarity of description, and are not intended to limit the scope of the present invention, and changes or modifications in the relative relationship may be made without substantial changes in the technical content.

The specific embodiment of the invention provides a harmonic speed reducer, which comprises a flexible gear 2 with an outer gear ring and a wave generator 1, wherein the wave generator 1 is rotatably arranged at the inner side of the flexible gear 2, the outer contour of the wave generator 1 is composed of four arc surfaces, and two adjacent arc surfaces are tangent. The outer contour of the wave generator 1 is composed of tangent arc surfaces, when the wave generator 1 rotates, the wave generator 1 extrudes the flexible gear 2 to deform, the reference circle of the upper external gear of the flexible gear 2 and the reference circle of the upper and lower meshing parts of the internal gear of the rigid gear are ensured to have the same curvature with the circular arc of the wave generator 1, thereby the flexible gear 2 and the rigid gear are perfectly engaged, engaged and meshed, the gear moves, the stress is uniform and normal when the flexible gear 2 and the internal gear on the rigid gear are engaged in gear movement, and the phenomena of collision, interference or tooth punching and the like do not occur when the flexible gear 2 and the internal gear on the rigid gear are engaged in gear movement. The outer gear ring of the flexible gear 2 of the harmonic speed reducer is well meshed with the rigid inner gear ring at the contact section, the shaking caused by poor gear meshing in the transmission process can be completely eliminated, the positioning precision of equipment is obviously improved, the gear meshing matching is good, gear abrasion or other gear mechanical damage is eliminated, the phenomena of fatigue pitting corrosion and the like of the gear are reduced, the metal fatigue abrasion is greatly reduced, the tooth root fracture condition of the flexible gear 2 is avoided, and the service life of the flexible gear 2 is greatly prolonged.

Fig. 2 and 3 show the configuration of four arc surfaces of the outer contour of the wave generator 1, which arc surfaces are represented by arc curves on each arc surface.

In example 1, as shown in fig. 2, the first arc surface 11 and the second arc surface 12 are two arcs having the same radius, the third arc surface 13 and the fourth arc surface 14 are two arcs having the same radius, and the radius of the first arc surface 11 and the radius of the second arc surface 12 are smaller than the radius of the third arc surface 13 and the radius of the fourth arc surface 14.

In example 2, as shown in fig. 3, the first arc surface 11 and the second arc surface 12 are two arcs having different radii, and the third arc surface 13 and the fourth arc surface 14 are two arcs having different radii.

In an alternative embodiment, the harmonic reducer comprises a flexible gear 2 and a wave generator 1, wherein the wave generator 1 is rotatably arranged inside the flexible gear 2, the outer contour of the wave generator 1 is composed of at least five arc surfaces, and two adjacent arc surfaces are tangent.

In an alternative embodiment, the harmonic reducer further comprises a compliant bearing 3, the compliant bearing 3 being disposed between the wave generator 1 and the compliant gear 2, reducing frictional resistance between the wave generator 1 and the compliant gear 2.

In an alternative embodiment, the harmonic reducer further comprises a rigid gear 4 with an inner ring gear, the rigid gear 4 being arranged outside the flexible gear 2, part of the gears of the inner ring gear and part of the gears of the outer ring gear being in mesh with each other. The flexible gear 2 generates elastic deformation, the part meshed with the gear teeth of the rigid gear 4 moves sequentially, and the gear teeth between the upper part and the lower part of the two wheels perform gear motion of meshing, separating, meshing and separating, so that transmission is performed repeatedly.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A harmonic speed reducer machine, its characterized in that: the flexible gear generator comprises a flexible gear (2) with an outer gear ring and a wave generator (1), wherein the wave generator (1) is rotatably arranged on the inner side of the flexible gear (2), the outer contour of the wave generator (1) is composed of four arc surfaces, and the two adjacent arc surfaces are tangent.

2. The harmonic reducer of claim 1, wherein: first arc surface (11) and second arc surface (12) are the circular arcs that two radiuses equal, and third arc surface (13) and fourth arc surface (14) are the circular arcs that two radiuses equal, first arc surface (11) with the radius of second arc surface (12) is less than third arc surface (13) with the radius of fourth arc surface (14).

3. The harmonic reducer of claim 1, wherein: the first arc surface (11) and the second arc surface (12) are arcs with unequal radiuses, and the third arc surface (13) and the fourth arc surface (14) are arcs with unequal radiuses.

4. A harmonic speed reducer machine, its characterized in that: including flexible gear (2) and wave generator (1), wave generator (1) rotationally sets up flexible gear (2) are inboard, the outline of wave generator (1) comprises five at least arc surfaces, adjacent two the arc surface is tangent.

5. The harmonic reducer of claim 1 or 4, wherein: the harmonic reducer further comprises a flexible bearing (3), and the flexible bearing (3) is arranged between the wave generator (1) and the flexible gear (2).

6. The harmonic reducer of claim 1 or 4, wherein: the harmonic speed reducer further comprises a rigid gear (4) with an inner gear ring, the rigid gear (4) is arranged on the outer side of the flexible gear (2), and part of gears of the inner gear ring and part of gears of the outer gear ring are meshed with each other.