Harmonic reducer and robot

Abstract

The harmonic reducer comprises a rigid gear, a flexible gear and a wave generator, the rigid gear is provided with an inner gear ring, the flexible gear is provided with an outer gear ring, the wave generator is arranged in the flexible gear, the rigid gear is arranged outside the flexible gear, the inner gear ring is meshed with the outer gear ring, and the outer gear ring is meshed with the inner gear ring. At least one of the inner gear ring and the outer gear ring is provided with a noise elimination groove extending in the circumferential direction, and teeth of at least one of the inner gear ring and the outer gear ring are disconnected in the axial direction of the harmonic reducer through the noise elimination groove. According to the technical scheme, the silencing groove is additionally formed in the gear ring part of the flexible gear or the rigid gear of the harmonic reducer, so that vibration and noise caused by operation of the harmonic reducer are reduced, the environment is improved, and the weight of the harmonic reducer is reduced.

Description

Technical Field

[0001] The present invention is used in the field of robots, and particularly relates to a harmonic reducer and a robot. Background Art

[0002] A harmonic reducer is a transmission method that relies on the elastic deformation of a flexible gear to transmit force and motion. A typical harmonic reducer consists of three components: a flexspline, a circular spline, and a wave generator. The flexspline is a flexible gear with an external tooth ring, and the circular spline is a rigid gear with an internal tooth ring. Usually, the circular spline is fixed, and the wave generator is an elliptical component installed inside the flexspline, forcing the flexspline to generate radial deformation at the long-axis end according to a certain law to become elliptical. When the wave generator is driven to rotate, it forces the flexspline to continuously generate deformation. During the deformation process, the teeth of the flexspline gradually enter between the teeth of the circular spline, engage with the teeth of the circular spline, and then gradually withdraw until they are completely disengaged. Thus, as the wave generator continuously rotates, the teeth of the flexspline continuously repeat the cycle of engaging, meshing, disengaging, and separating with the teeth of the circular spline, and this misalignment movement converts the input of the wave generator into the output of the flexspline to achieve a speed reduction movement.

[0003] Generally, when a harmonic reducer is operating, vibration and noise are generated due to tooth profile design, manufacturing, and assembly errors, etc. When manufacturing and assembly errors, etc. become larger, the vibration and noise also become larger. With the development of technology, the application industry has put forward higher and higher requirements for harmonic reducers, especially high requirements in terms of vibration, noise, and lightweight.

[0004] In summary, the problems existing in the related art urgently need to be solved. Summary of the Invention

[0005] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art, and provide a harmonic reducer and a robot, adding a sound-absorbing groove to the tooth ring part of the flexspline or the circular spline of the harmonic reducer to reduce the vibration and noise generated during the operation of the harmonic reducer, improve the environment, and reduce the weight of the harmonic reducer.

[0006] The technical solution adopted by the present invention to solve its technical problems is:

[0007] In a first aspect, a harmonic reducer includes a circular spline, a flexspline, and a wave generator. The circular spline is provided with an internal tooth ring, the flexspline is provided with the external tooth ring, the wave generator is arranged inside the flexspline, the circular spline is arranged outside the flexspline, the internal tooth ring meshes with the external tooth ring, and at least one of the internal tooth ring and the external tooth ring is provided with a sound-absorbing groove extending circumferentially, and the sound-absorbing groove disconnects the teeth of at least one of the internal tooth ring and the external tooth ring along the axial direction of the harmonic reducer.

[0008] In connection with the first aspect, in certain implementations of the first aspect, the noise cancellation groove includes a first noise cancellation groove provided on the internal gear ring, and the first noise cancellation groove divides the teeth of the internal gear ring into multiple segments along the axial direction.

[0009] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the first noise cancellation groove extends continuously along the circumferential direction of the internal gear ring.

[0010] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the first noise cancellation groove is discontinuously distributed along the circumferential direction of the internal gear ring.

[0011] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the internal gear ring is provided with a plurality of the first noise cancellation grooves, and the plurality of the first noise cancellation grooves are spaced apart along the axial direction.

[0012] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the noise cancellation groove includes a second noise cancellation groove provided on the external gear ring, and the second noise cancellation groove divides the teeth of the external gear ring into multiple segments along the axial direction.

[0013] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the second noise cancellation groove extends continuously along the circumferential direction of the external gear ring.

[0014] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the second noise cancellation groove is discontinuously distributed along the circumferential direction of the external gear ring.

[0015] In connection with the first aspect and the above implementation, in certain implementations of the first aspect, the external gear ring is provided with a plurality of the second noise cancellation grooves, and the plurality of the second noise cancellation grooves are spaced apart along the axial direction.

[0016] In a second aspect, a robot includes the harmonic reducer according to any one of the implementations in the first aspect.

[0017] At least one of the following advantages or beneficial effects exists in one of the technical solutions in the above technical solutions:

[0018] In the technical solution of the present invention, at least one of the internal gear ring and the external gear ring is provided with a sound-absorbing groove extending circumferentially. The cross-section of the sound-absorbing groove is rectangular, wedge-shaped or stepped. When the harmonic reducer operates, the internal gear ring of the rigid gear and the external gear ring of the flexible gear are engaged and driven. Among them, the vibrations and noises generated by the meshing of the teeth on both sides of the sound-absorbing groove will spread to the surroundings. When the energy on both sides of the sound-absorbing groove is transmitted to the sound-absorbing groove, due to the strong viscous friction generated by the sound wave in the object and the internal resonance effect, part of the energy is dissipated, the sound wave intensity is weakened, and the propagation of the sound wave is inhibited, so as to achieve the purpose of reducing the overall vibration and noise. Compared with the ordinary harmonic reducer, the harmonic reducer of the present invention has been tested. Under the same application conditions, the overall vibration generated is reduced by two-thirds, perfectly meeting the requirements of the harmonic reducer for reducing vibration and noise.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0021] Figure 1 is a schematic structural diagram of an embodiment of the present invention using a top-hat type flexible gear;

[0022] Figure 2 is a schematic structural diagram of an embodiment of the present invention with a sound-absorbing groove provided in the internal gear ring of the rigid gear;

[0023] Figure 3 is a schematic structural diagram of an embodiment of the present invention with a sound-absorbing groove provided in the external gear ring of the top-hat type flexible gear;

[0024] Figure 4 is a schematic structural diagram of an embodiment of the present invention using a cup-shaped flexible gear;

[0025] Figure 5 is a schematic structural diagram of an embodiment of the present invention with a sound-absorbing groove provided in the external gear ring of the cup-shaped flexible gear. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] This part will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the drawings. The function of the drawings is to supplement the description of the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the protection scope of the present invention.

[0027] In the present invention, when directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, rather than indicating or implying that the technical features referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0028] In the present invention, the meaning of "a number of" is one or more, the meaning of "a plurality of" is two or more, and "greater than", "less than", "exceeding", etc. are understood to exclude the base number; "above", "below", "within", etc. are understood to include the base number. In the description of the present invention, if "first" and "second" are described, they are only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0029] In the present invention, unless otherwise clearly defined, terms such as "arranged", "installed", "connected", etc. should be understood in a broad sense. For example, they can be directly connected, or indirectly connected through an intermediate medium; they can be fixedly connected, or detachably connected, or integrally formed; they can be mechanically connected, or electrically connected or capable of communicating with each other; they can be the communication inside two components or the interaction relationship between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in the present invention in combination with the specific content of the technical solution.

[0030] See Figures 1 - 5 , an embodiment of the present invention provides a harmonic reducer, which includes a rigid gear 100, a flexible gear 200 and a wave generator 300. The rigid gear 100 is provided with an internal gear ring 101, the flexible gear 200 is provided with an external gear ring 201, the wave generator 300 is arranged inside the flexible gear 200, the rigid gear 100 is arranged outside the flexible gear 200, the internal gear ring 101 meshes with the external gear ring 201, and at least one of the internal gear ring 101 and the external gear ring 201 is provided with a sound-absorbing groove extending in the circumferential direction, and the sound-absorbing groove disconnects the teeth of at least one of the internal gear ring 101 and the external gear ring 201 along the axial direction of the harmonic reducer. It can be understood that in the embodiment of the present invention, the depth of the sound-absorbing groove and the height of the teeth of the internal gear ring 101 and the external gear ring 201 are not limited, that is, the depth of the sound-absorbing groove can be greater than the height of the teeth of the internal gear ring 101 and the external gear ring 201, or less than or equal to the height of the teeth of the internal gear ring 101 and the external gear ring 201.

[0031] When the wave generator 300 is driven to rotate, it forces the flexspline 200 to continuously deform. The external tooth ring 201 of the flexspline 200 gradually enters between the internal tooth rings 101 of the rigid ring 100 during the deformation process, meshes with the internal tooth rings 101 of the rigid ring 100, and then gradually exits until it is completely disengaged. Thus, as the wave generator 300 continuously rotates, the external tooth ring 201 of the flexspline 200 and the internal tooth ring 101 of the rigid ring 100 repeatedly perform a cycle of engaging, meshing, disengaging, and separating with staggered teeth. This staggered tooth movement converts the input of the wave generator 300 into the output of the flexspline 200 to achieve a speed reduction movement.

[0032] Combined with Figures 1 - 5 , in the technical solution of the present invention, at least one of the internal tooth ring 101 and the external tooth ring 201 is provided with a sound-absorbing groove extending in the circumferential direction. The cross-section of the sound-absorbing groove is rectangular or wedge-shaped or stepped. When the harmonic reducer operates, the internal tooth ring 101 of the rigid ring 100 and the external tooth ring 201 of the flexspline 200 are engaged in transmission. Among them, the vibrations and noises generated by the meshing of the teeth on both sides of the sound-absorbing groove will spread around. When the energy on both sides of the sound-absorbing groove is transmitted to the sound-absorbing groove, due to the strong viscous friction generated by the sound wave in the object and the internal resonance effect, part of the energy is dissipated, weakening the sound wave intensity and suppressing the propagation of the sound wave, thereby achieving the purpose of reducing the overall vibration and noise. Compared with ordinary harmonic reducers, the harmonic reducer of the present invention has been tested. Under the same application conditions, the overall vibration generated is reduced by two-thirds, perfectly meeting the requirements of the harmonic reducer for reducing vibration and noise.

[0033] The embodiments of the present invention change the structure of the tooth parts of the rigid ring 100 or the flexspline 200 of the harmonic reducer to reduce the vibration and noise of the harmonic reducer; at the same time, under the same vibration and noise requirements, the manufacturing difficulty of the harmonic reducer can also be relaxed.

[0034] In some embodiments, referring to Figure 1 , the sound-absorbing groove includes a first sound-absorbing groove 102 provided on the internal tooth ring 101. The first sound-absorbing groove 102 divides the teeth of the internal tooth ring 101 into multiple segments along the axial direction. In this embodiment, the first sound-absorbing groove 102 is circumferentially provided at the internal tooth ring 101 of the rigid ring 100. The first sound-absorbing groove 102 is rectangular or wedge-shaped or has a multi-layer structure, dividing the internal tooth ring 101 of the rigid ring 100 into upper and lower parts. The parameters such as the module and the number of teeth of the two parts of the teeth are the same.

[0035] When the harmonic reducer operates, the vibrations and noises generated by the meshing of the gears at the upper and lower parts of the first sound-absorbing groove 102 will spread around. When the energy at the upper and lower parts is transmitted to the first sound-absorbing groove 102, due to the strong viscous friction generated by the sound wave in the object and the internal resonance effect, part of the energy is dissipated, weakening the sound wave intensity and suppressing the propagation of the sound wave, thereby achieving the purpose of reducing the overall vibration and noise.

[0036] In some embodiments, the first sound-absorbing groove 102 extends continuously along the circumferential direction of the internal gear ring 101. The first sound-absorbing groove 102 can be a complete circle or a spiral shape.

[0037] In some embodiments, the first sound-absorbing grooves 102 are distributed intermittently along the circumferential direction of the internal gear ring 101. At this time, the first sound-absorbing grooves 102 distributed intermittently along the circumferential direction can be located on the same circumference or can be axially offset and located on different circumferences.

[0038] In some embodiments, the internal gear ring 101 is provided with a plurality of first sound-absorbing grooves 102, and the plurality of first sound-absorbing grooves 102 are distributed at intervals along the axial direction.

[0039] In some embodiments, referring to Figure 3 , the sound-absorbing groove includes a second sound-absorbing groove 202 provided on the external gear ring 201. The second sound-absorbing groove 202 divides the teeth of the external gear ring 201 into multiple segments along the axial direction. In this embodiment, the second sound-absorbing groove 202 is provided along the circumferential direction of the external gear ring 201. The second sound-absorbing groove 202 is rectangular or wedge-shaped or a multi-layer structure, dividing the internal gear ring 101 of the rigid gear 100 into upper and lower parts, and the parameters such as the module and the number of teeth of the two parts of the teeth are the same.

[0040] When the harmonic reducer operates, the vibrations and noises generated by the meshing of the gears at the upper and lower parts of the second sound-absorbing groove 202 will spread to the surroundings. When the energy at the upper and lower parts is transmitted to the second sound-absorbing groove 202, due to the strong viscous friction generated by the sound wave in the object and the internal resonance effect, part of the energy is dissipated, weakening the sound wave intensity and suppressing the propagation of the sound wave, so as to achieve the purpose of reducing the overall vibration and noise.

[0041] In some embodiments, the second sound-absorbing groove 202 extends continuously along the circumferential direction of the external gear ring 201.

[0042] In some embodiments, the second sound-absorbing groove 202 is distributed intermittently along the circumferential direction of the external gear ring 201.

[0043] In some embodiments, the external gear ring 201 is provided with a plurality of second sound-absorbing grooves 202, and the plurality of second sound-absorbing grooves 202 are distributed at intervals along the axial direction.

[0044] It can be understood that in some embodiments, sound-absorbing grooves can also be provided on the internal gear ring 101 of the rigid gear 100 and the external gear ring 201 of the flexible gear 200 at the same time.

[0045] It can be understood that, in addition to classifying the harmonic reducer according to the shape of the flexible gear 200 Figures 1 - 3In addition to the top hat type with standard length, there are also the top hat type short barrel flex spline 200, the cup type standard flex spline 200, and the cup type short barrel flex spline 200. The present invention is not limited to being used in the structure of the top hat type flex spline 200, but can also be used in harmonic speed reducers with the other three structures, such as Figure 4 , Figure 5 which is applied to the cup type harmonic speed reducer.

[0046] An embodiment of the present invention also provides a robot, including the harmonic speed reducer in any one of the above embodiments.

[0047] In the description of this specification, the description with reference to terms such as "example", "embodiment", or "some embodiments" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0048] Of course, the present invention is not limited to the above embodiments. Those skilled in the art can also make equivalent deformations or substitutions without departing from the spirit of the present invention, and these equivalent deformations or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A harmonic reducer, characterized in that, It includes a rigid gear, a flexible gear and a wave generator. The rigid gear is provided with an internal gear ring, the flexible gear is provided with an external gear ring, the wave generator is arranged inside the flexible gear, the rigid gear is arranged outside the flexible gear, the internal gear ring meshes with the external gear ring, at least one of the internal gear ring and the external gear ring is provided with a sound-absorbing groove extending circumferentially, and the sound-absorbing groove disconnects the teeth of at least one of the internal gear ring and the external gear ring along the axial direction of the harmonic reducer.

2. The harmonic reducer according to claim 1, characterized in that The sound-absorbing groove includes a first sound-absorbing groove arranged on the internal gear ring, and the first sound-absorbing groove axially divides the teeth of the internal gear ring into multiple segments.

3. The harmonic reducer according to claim 2, wherein The first sound-absorbing groove extends continuously along the circumferential direction of the internal gear ring.

4. The harmonic reducer according to claim 2, wherein, The first sound-absorbing groove is distributed intermittently along the circumferential direction of the internal gear ring.

5. The harmonic reducer according to claim 2, characterized in that, The internal gear ring is provided with a plurality of the first sound-absorbing grooves, and the plurality of the first sound-absorbing grooves are distributed at intervals along the axial direction.

6. The harmonic reducer according to claim 1, wherein The sound-absorbing groove includes a second sound-absorbing groove arranged on the external gear ring, and the second sound-absorbing groove axially divides the teeth of the external gear ring into multiple segments.

7. The harmonic reducer according to claim 5, wherein The second sound-absorbing groove extends continuously along the circumferential direction of the external gear ring.

8. The harmonic reducer according to claim 5, wherein The second sound-absorbing groove is distributed intermittently along the circumferential direction of the external gear ring.

9. The harmonic reducer according to claim 5, wherein The external gear ring is provided with a plurality of the second sound-absorbing grooves, and the plurality of the second sound-absorbing grooves are distributed at intervals along the axial direction.

10. A robot, characterized in that, It includes the harmonic reducer according to any one of claims 1 to 9.

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