High-precision harmonic reducer

Abstract

The high-precision harmonic reducer comprises a cross bearing, a flexible gear, a rigid gear and a wave generator, the rigid gear is fixed to an inner ring of the cross bearing, the flexible gear is concentrically arranged on the inner ring of the cross bearing, the end portion of the flexible gear extends from the other end of the cross bearing and then is fixed to an outer ring of the cross bearing, and the wave generator is concentrically arranged in the flexible gear. The wave generator is directly contacted with the inner surface of the flexible gear for transmission, a lubricating structure is arranged between the contact surfaces of the wave generator and the flexible gear, the wave generator is used for directly driving the flexible gear, zero-backlash driving can be realized, the repeated positioning precision is high, and the driving precision of the harmonic reducer is improved.

Description

Technical Field

[0001] This utility model relates to the field of speed reducers and specifically to a high-precision harmonic speed reducer. Background Technology

[0002] Harmonic reducers are commonly used in mechanical systems that require small size, light weight, and high transmission ratio, such as robot joints, aerospace mechanisms, and precision instruments. During operation, the wave generator drives the flexible wheel to rotate through the flexible bearing, which in turn drives the rigid wheel. The lifespan of existing harmonic reducers is limited by the lifespan of the flexible bearing. In addition, due to the presence of the flexible bearing, there is a backlash of about 10-20 arcseconds, which limits the repeatability and positioning accuracy, making it impossible to achieve efficient and precise transmission over a long period of time, thus affecting the operation of the equipment. Utility Model Content

[0003] Technical objective: To address the shortcomings of existing harmonic reducers, this utility model discloses a high-precision harmonic reducer.

[0004] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution:

[0005] A high-precision harmonic reducer includes a cross bearing, a flexible wheel, a rigid wheel, and a wave generator. The rigid wheel is fixed to the inner ring of the cross bearing. The flexible wheel is concentrically disposed on the inner ring of the cross bearing, with its end extending from the other end of the cross bearing and fixed to the outer ring of the cross bearing. The wave generator is concentrically disposed inside the flexible wheel and directly contacts the inner surface of the flexible wheel for transmission. A lubrication structure is provided between the contact surfaces of the wave generator and the flexible wheel.

[0006] Preferably, the lubrication structure of this utility model includes lubricating oil disposed between the contact surface of the wave generator and the flexible wheel, wherein the lubricating oil forms an oil film on the contact surface during the operation of the wave generator; and a pit structure is provided on the surface of the wave generator to enhance the uniformity of the oil film.

[0007] Preferably, the recessed structure of this utility model includes a number of regularly spaced spherical recesses at the contact surface between the wave generator and the flexure, the spherical recesses being filled with lubricating oil to lubricate the surface of the contacting flexure during the rotation of the wave generator.

[0008] Preferably, the spherical pits of this invention are arranged in columns along the axial direction of the wave generator, and the spacing between each column of spherical pits is equal.

[0009] Preferably, the depth of the spherical recess in this invention is between 1 / 10 and 1 / 5 of the radius of the spherical recess.

[0010] Preferably, the radius of the spherical recess of this invention is 0.1-10 mm.

[0011] Beneficial effects: The high-precision harmonic reducer disclosed in this utility model has the following beneficial effects:

[0012] 1. This utility model uses a wave generator to directly drive the flexible wheel, which can achieve zero backlash drive, high repeatability and positioning accuracy, and improve the driving accuracy of the harmonic reducer. At the same time, by reducing the flexible bearing, the inner hole size can be increased, thereby meeting the application requirements of hollow type applications that require larger diameter cables or motors to pass through.

[0013] 2. This utility model is not affected by the lifespan of the flexural bearing, is easy to install, can improve the service life, and has high rigidity, enabling high torque drive.

[0014] 3. This utility model forms an oil film between the wave generator and the flexible wheel through spherical pits and lubricating oil, which can effectively reduce wear. In addition, the spherical pits can store fine abrasive particles caused by wear, preventing the product from failing prematurely due to wear. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0016] Figure 1 This is a structural diagram of the harmonic reducer of this utility model;

[0017] Figure 2 This is a schematic diagram of the recess structure of this utility model;

[0018] Among them, 1-cross bearing, 2-flexible wheel, 3-rigid wheel, 4-wave generator, 101-inner ring, 102-outer ring, 5-spherical pit. Detailed Implementation

[0019] Reference will now be made in detail to embodiments of the present disclosure, one or more of which are set forth herein. Each embodiment and example is provided by way of explanation of the apparatus, composition, and materials of the present disclosure, and not by way of limitation. Rather, the following description provides convenient illustrations for implementing exemplary embodiments of the present disclosure. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the teachings of the present disclosure without departing from the scope or spirit of the present disclosure.

[0020] like Figure 1 and Figure 2As shown, this utility model discloses a high-precision harmonic reducer, including a cross bearing 1, a flexible wheel 2, a rigid wheel 3, and a wave generator 4. The cross bearing 1, flexible wheel 2, and rigid wheel 3 are all existing mature structures. The flexible wheel 2 has a cup-shaped structure. The rigid wheel 3 is fixed to the inner ring 101 of the cross bearing 1. The flexible wheel 2 is concentrically arranged in the inner ring 101 of the cross bearing 1, and its end extends from the other end of the cross bearing 1 and is fixed to the outer ring 102 of the cross bearing 1. The wave generator 4 is concentrically arranged in the flexible wheel 2 and directly contacts the inner surface of the flexible wheel 2 for harmonic transmission, eliminating the need for a flexible wheel bearing. This improves the stiffness of the reducer and increases the backlash, ensuring the repeatability of the harmonic reducer and achieving high-precision and high-torque drive. By eliminating the flexible bearing, the number of parts in the reducer is reduced, which is beneficial for the assembly and fitting of the structure. A lubrication structure is provided between the contact surfaces of the wave generator 4 and the flexible wheel 2.

[0021] The lubrication structure of this invention is used to reduce wear between contact surfaces to improve the service life of the harmonic reducer, such as... Figure 2 As shown, the lubrication structure of this utility model includes lubricating oil disposed between the contact surfaces of the wave generator 4 and the flexible wheel 2. The lubricating oil forms an oil film on the contact surface during the operation of the wave generator 4. A pit structure is provided on the surface of the wave generator 4 to enhance the uniformity of the oil film. The pit structure includes a number of regularly spaced spherical pits 5 at the contact surfaces of the wave generator 4 and the flexible wheel 2. The spherical pits 5 are filled with lubricating oil. During the rotation of the wave generator 4, the contacting surface of the flexible wheel 2 is lubricated, improving the uniformity of the oil film and reducing wear. Compared with the use of flexible bearings, this utility model can increase the service life of the reducer by more than double.

[0022] Specifically, to ensure the uniformity of the oil film, the spherical pits of this invention are arranged in columns along the axial direction of the wave generator, with equal spacing between each column of spherical pits. The depth of the spherical pit 5 is between 1 / 10 and 1 / 5 of the radius of the spherical pit, to ensure that a uniform oil film is formed between the contact surfaces. In the embodiments of this invention, the size of the spherical pits can be set based on the specifications of the harmonic reducer used. Theoretically, the smaller the size, the better the uniformity of the oil film and the lubrication effect. The radius of the spherical pit 5 used in this invention is 0.1-10mm.

[0023] In use, the wave generator 4 is connected to the input shaft via a keyway, driving its movement. The wave generator 4, through its elliptical outer surface, causes the inner hole of the flexible wheel 2 to continuously deform, resulting in a differential gear motion between the flexible wheel 2 and the rigid wheel 3, thus transmitting torque. Both the flexible wheel 2 and the rigid wheel 3 are fixed to the cross bearing with screws, and the bearings assist in rotation. When the rigid wheel 3 (or the flexible wheel 2) acts as a fixed component, the corresponding flexible wheel 2 (or rigid wheel 3) becomes the output component. During operation, the spherical recess 5 serves as an oil storage function and stores fine abrasive particles caused by wear, preventing premature product failure due to wear.

[0024] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-precision harmonic reducer, characterized by, The device includes a cross bearing (1), a flexible wheel (2), a rigid wheel (3), and a wave generator (4). The rigid wheel (3) is fixed to the inner ring (101) of the cross bearing (1). The flexible wheel (2) is concentrically arranged in the inner ring (101) of the cross bearing (1). Its end extends from the other end of the cross bearing (1) and is fixed to the outer ring (102) of the cross bearing (1). The wave generator (4) is concentrically arranged inside the flexible wheel (2) and directly contacts the inner surface of the flexible wheel (2) for transmission. A lubrication structure is provided between the contact surfaces of the wave generator (4) and the flexible wheel (2).

2. The high-precision harmonic reducer according to claim 1, characterized in that, The lubrication structure includes lubricating oil disposed between the contact surfaces of the wave generator (4) and the flexible wheel (2), wherein the lubricating oil forms an oil film on the contact surface during the operation of the wave generator (4); and a pit structure is provided on the surface of the wave generator (4) to enhance the uniformity of the oil film.

3. A high-precision harmonic reducer according to claim 2, characterized in that, The recessed structure includes several regularly spaced spherical recesses (5) at the contact surface between the wave generator (4) and the flexible wheel (2). The spherical recesses (5) are filled with lubricating oil, which lubricates the surface of the contacting flexible wheel (2) during the rotation of the wave generator (4).

4. The high-precision harmonic reducer according to claim 3, characterized in that, The spherical pits are arranged in columns along the axial direction of the wave generator, with equal spacing between each column of spherical pits.

5. The high-precision harmonic reducer according to claim 3, wherein The depth of the spherical pit (5) is between 1 / 10 and 1 / 5 of the radius of the spherical pit.

6. A high-precision harmonic reducer according to any one of claims 3-5, characterized in that, The radius of the spherical pit (5) is 0.1-10 mm.

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