阅读说明：本技术 一种双弧曲面谐波传动减速器 (Double-arc curved surface harmonic drive speed reducer ) 是由 侯国兴 王伟 于 2021-08-25 设计创作，主要内容包括：本申请涉及减速器技术领域,公开了一种双弧曲面谐波传动减速器,包括柔轮、输入钢轮、输出钢轮和波发生器,波发生器设置在柔轮内侧,具有双弧曲面齿廓的柔轮外侧设有外齿,柔轮的外齿包括第一级外齿和第二级外齿,第一级外齿和第二级外齿分别位于柔轮外壁两侧,第一级外齿与钢轮的内齿啮合,第二级外齿与输出钢轮的内齿啮合,波发生器与电机的输出轴固定连接,输入钢轮固定连接于双弧曲面谐波传动减速器的机座,输出钢轮固定连接输出轴；第一级外齿和第二级外齿的齿数不同,模数不同,并分布在同一分度圆上。本申请的速比可在300-900之间,工作噪音低,承载能力强。(The utility model relates to the technical field of speed reducer, a double-arc curved surface harmonic drive speed reducer is disclosed, including the flexbile gear, the input steel wheel, output steel wheel and wave generator, the wave generator sets up at the flexbile gear inboard, the flexbile gear outside that has double-arc curved surface profile of tooth is equipped with the external tooth, the external tooth of flexbile gear includes first order external tooth and second level external tooth, first order external tooth and second level external tooth are located flexbile gear outer wall both sides respectively, first order external tooth and the internal gearing of steel wheel, the internal gearing of second level external tooth and output steel wheel, the output shaft fixed connection of wave generator and motor, input steel wheel fixed connection is in double-arc curved surface harmonic drive speed reducer's frame, output steel wheel fixed connection output shaft; the first-stage external teeth and the second-stage external teeth have different tooth numbers and different modulus and are distributed on the same reference circle. The speed ratio of the application can be between 300 and 900, the working noise is low, and the bearing capacity is strong.)

1. A double-arc curved surface harmonic drive reducer comprises a flexible gear (1), an input steel gear (2), an output steel gear (3) and a wave generator (4), it is characterized in that the wave generator (4) is arranged at the inner side of the flexible gear (1), the outer side of the flexible gear (1) is provided with outer teeth, the outer teeth of the flexible gear (1) comprise a first-stage outer tooth (11) and a second-stage outer tooth (12) which are coaxial, the first-stage external teeth (11) and the second-stage external teeth (12) are respectively positioned on two sides of the outer wall of the flexible gear (1), the first-stage external teeth (11) are meshed with the internal teeth of the input steel wheel (2), the second-stage external teeth (12) are meshed with the internal teeth of the output steel wheel (3), the wave generator (4) is fixedly connected with an input shaft of the motor, the input steel wheel (2) is fixedly connected with a base of the double-arc curved surface harmonic transmission reducer, and the output steel wheel (3) is fixedly connected with an output shaft; the first-stage external teeth (11) and the second-stage external teeth (12) are distributed on the same reference circle, and have different tooth numbers and different modulus.

2. A double arc curved harmonic drive reducer as defined in claim 1 in which the number of teeth of the first stage outer teeth (11) is less than the number of teeth of the input steel wheel (2) and the number of teeth of the second stage outer teeth (12) is less than the number of teeth of the output steel wheel (3).

3. The double-arc curved surface harmonic drive reducer according to claim 1 or 2, wherein the tooth profiles of the first-stage external teeth (11) and the second-stage external teeth (12) are involute tooth profiles, and the tooth crests and the tooth roots of the involute tooth profiles are arc transitions (13).

4. A double-arc-curved-surface harmonic drive reducer according to claim 3, wherein the addendum arc radius of the first-stage external teeth (11) and the modulus ratio thereof, and the addendum arc radius of the second-stage external teeth (12) and the modulus ratio thereof are each 0.2 to 0.3.

5. A double-arc-curved-surface harmonic drive reducer according to claim 3 in which the arc radius of the roots of said first-stage external teeth (11) and the ratio of the number of the modes thereof, and the arc radius of the roots of said second-stage external teeth (12) and the ratio of the number of the modes thereof are each 0.3 to 0.5.

6. A double-arc-curved-surface harmonic drive reducer according to claim 3 wherein the addendum arc radius of the first-stage external teeth (11) is larger than the dedendum arc radius thereof, and the addendum arc radius of the second-stage external teeth (12) is larger than the dedendum arc radius thereof by 1.2 to 1.3.

7. A double-arc-curved-surface harmonic drive reducer according to claim 1, wherein the tooth width of the first-stage external teeth (11) is 1-2mm smaller than that of the input steel wheel (2), and the tooth width of the second-stage external teeth (12) is 1-2mm smaller than that of the output steel wheel (3).

8. The double-arc-surface harmonic drive speed reducer according to claim 1, wherein the ratio of the depth of engagement of the first-stage external teeth (11) when fully engaged with the input steel wheel (2) to the modulus of the first-stage external teeth (11), and the ratio of the depth of engagement of the second-stage external teeth (12) when fully engaged with the output steel wheel (3) to the modulus of the second-stage external teeth (12) are each 1.1 to 1.3.

Technical Field

The application relates to the technical field of speed reducers, in particular to a double-arc curved surface harmonic drive speed reducer.

Background

Harmonic drive reducer drive technology and drives have been widely used in a variety of fields. The core components of the harmonic drive reducer are a flexible gear, a rigid gear and a wave generator, the flexible gear deforms under the action of the wave generator, and gear teeth of the flexible gear at two ends of a long shaft of the wave generator are completely meshed with gear teeth of the rigid gear; the flexible gear teeth and the rigid gear teeth at the two ends of the short shaft are completely disengaged; in the interval of the long axis and the short axis of the wave generator, some of the flexible gear teeth and the rigid gear teeth are in a semi-meshed state; some of them are gradually withdrawn from engagement and are in a half-disengaged state.

The speed reduction ratio of the single-stage speed reduction of the harmonic drive speed reducer is usually between 50 and 300, and the speed reduction ratio range of the double-stage speed reduction is between 1000 and 50000, which is restricted by the fatigue strength mechanical transmission principle, so that the requirement of customers on the speed ratio of the harmonic drive speed reducer between 300 and 900 cannot be met, and the application range of the harmonic drive speed reducer is limited.

The flexible gear of the harmonic drive reducer is mainly under the combined action of bending alternating stress and torsional shear stress, the existing involute tooth form is in transmission, the joint of the tooth top and the tooth profile is a sharp angle, and the tooth of the flexible gear is easy to generate tooth profile interference and tooth top interference in the process of meshing in and out with the tooth of the rigid gear, so that noise is generated; the flexible gear is a thin-wall part, the transition fillet of the involute tooth-shaped tooth root is small, stress concentration is easy to cause tooth root fracture, and the bearing capacity is limited.

Disclosure of Invention

In order to improve the application range of the harmonic drive reducer, meet the requirement that the speed ratio is between 300 and 900, reduce the working noise of the harmonic drive reducer and improve the bearing capacity, the application provides the double-arc curved surface harmonic drive reducer.

The above application purpose of the present application is achieved by the following technical solutions:

a double-arc curved surface harmonic drive reducer comprises a flexible gear, an input steel gear, an output steel gear and a wave generator, wherein the wave generator is arranged on the inner side of the flexible gear, outer teeth are arranged on the outer side of the flexible gear, the outer teeth of the flexible gear comprise first-stage outer teeth and second-stage outer teeth which are coaxial, the first-stage outer teeth and the second-stage outer teeth are respectively positioned on two sides of the outer wall of the flexible gear, the first-stage outer teeth are meshed with the inner teeth of the input steel gear, the second-stage outer teeth are meshed with the inner teeth of the output steel gear, the wave generator is fixedly connected with an input shaft of a motor, the input steel gear is fixedly connected to a base of the double-arc curved surface harmonic drive reducer, and the output steel gear is fixedly connected with an output shaft; the first-stage external teeth and the second-stage external teeth are distributed on the same reference circle, and have different tooth numbers and different modulus.

Through adopting above-mentioned technical scheme, the flexbile gear sets to coaxial first order external tooth and second level external tooth to have different number of teeth and modulus, there are different deformation waves at the in-process that realizes the variable speed, and the input rigid wheel is fixed on the casing, and the output rigid wheel is connected the output shaft, and the reduction gear adopts harmonic transmission to carry out the two-stage speed reduction, thereby realizes 300 ability of honour 900's reduction ratio requirement between.

Preferably, the number of teeth of the first-stage external teeth is less than that of the input steel wheel, and the number of teeth of the second-stage external teeth is less than that of the output steel wheel.

By adopting the technical scheme, the tooth number of the first-stage external teeth is smaller than that of the input steel wheel, and the input steel wheel is fixedly connected to the base, so that first-stage speed reduction transmission can be realized; the number of teeth of the second-stage external teeth is smaller than that of the output steel wheel, so that two-stage speed reduction transmission can be realized; thereby realizing the harmonic drive deceleration of the speed reducer.

Preferably, the tooth profiles of the first-stage external teeth and the second-stage external teeth are involute tooth profiles, and tooth crests and tooth roots of the involute tooth profiles are circular arc transitions.

Through adopting above-mentioned technical scheme, can prevent that the first order external tooth on the flexbile gear is at the in-process of nibbling with the input steel wheel to and the second level external tooth takes place the addendum or the tooth root phenomenon of interfering at the in-process of nibbling with the output steel wheel, reduce double-arc curved surface harmonic drive reduction gear's noise, improve bearing capacity, the transmission precision of flexbile gear is high, life.

Preferably, the addendum arc radius of the first-stage external teeth and the modulus ratio thereof, and the addendum arc radius of the second-stage external teeth and the modulus ratio thereof are both 0.2 to 0.3.

By adopting the technical scheme, the tooth crest interference is avoided in the process of engagement and disengagement, so that the engagement and disengagement are smoother, and the engagement noise is reduced.

Preferably, the ratio of the circular arc radius of the tooth root of the first-stage external tooth to the modulus thereof, and the ratio of the circular arc radius of the tooth root of the second-stage external tooth to the modulus thereof are both 0.3 to 0.5.

By adopting the technical scheme, stress concentration is avoided, the possibility of tooth root fracture is reduced, and the bearing capacity is improved.

Preferably, the ratio of the addendum arc radius to the dedendum arc radius of the first-stage external teeth is 1.2 to 1.3, and the ratio of the addendum arc radius to the dedendum arc radius of the second-stage external teeth is 1.2 to 1.3.

By adopting the technical scheme, the tooth profile is prevented from interfering in the process of engagement and disengagement, so that the engagement and disengagement are smoother, and the noise generated by engagement can be reduced.

Preferably, the tooth width of the first-stage external teeth is 1-2mm smaller than that of the input steel wheel, and the tooth width of the second-stage external teeth is 1-2mm smaller than that of the output steel wheel

Through adopting above-mentioned technical scheme, can guarantee first order external tooth and input steel wheel to and the good meshing of second order external tooth and output steel wheel, and can be less flexible wheel's volume.

Preferably, the ratio of the depth of engagement of the first-stage external teeth into the input steel wheel to the modulus of the first-stage external teeth is 1.1 to 1.3, and the ratio of the depth of engagement of the second-stage external teeth into the output steel wheel to the modulus of the second-stage external teeth is 1.1 to 1.3.

Through adopting above-mentioned technical scheme, improve the first order external tooth and nibble completely the input steel wheel to and the second level external tooth is nibble completely the meshing number of teeth of the output steel wheel, increase the bearing capacity of reduction gear.

To sum up, the beneficial technical effect of this application does:

this application is through setting up first order external tooth and second level external tooth in the flexbile gear outside, the internal toothing of first order external tooth and steel wheel, the internal toothing of second level external tooth and output steel wheel, the output shaft fixed connection of wave generator and motor, input steel wheel fixed connection is in the frame of double-arc curved surface harmonic drive reduction gear, output steel wheel fixed connection output shaft, first order external tooth and second level external tooth distribute on same graduated circle, and the number of teeth is different, the modulus is different. The requirement that the speed ratio of the double-arc curved surface harmonic transmission speed reducer is between 300 and 900 can be met, and the application industry and the scene are wider.

This application sets up the circular arc transition through addendum and the tooth root at the first order external tooth of flexbile gear and second level external tooth, and when flexbile gear and input steel wheel and output steel wheel meshing, avoid taking place addendum or tooth root interference phenomenon, can reduce the noise of double-arc curved surface harmonic drive reduction gear, improve bearing capacity, improve transmission precision height, increase of service life.

Drawings

FIG. 1 is a cross-sectional view of the present application;

FIG. 2 is a view in the direction A of FIG. 1;

fig. 3 is an enlarged view of a portion B of fig. 2.

Figure 1, flexspline; 11. a first stage outer teeth; 12. a second stage external tooth; 13. arc transition; 2. inputting a steel wheel; 3. outputting a steel wheel; 4. a wave generator.

Detailed Description

The present application is described in further detail below with reference to figures 1-3.

As shown in fig. 1, the application relates to a double-arc curved surface harmonic transmission speed reducer, which comprises a flexible gear 1, an input steel gear 2, an output steel gear 3 and a wave generator 4, wherein the wave generator 4 is arranged on the inner side of the flexible gear 1, the flexible gear 1 adopts a double-arc curved surface tooth profile, outer teeth are arranged on the outer side of the flexible gear 1, the outer teeth of the flexible gear 1 comprise coaxial first-stage outer teeth 11 and second-stage outer teeth 12, the first-stage outer teeth 11 and the second-stage outer teeth 12 are respectively positioned on two sides of the flexible gear 1, the first-stage outer teeth 11 of the flexible gear 1 are meshed with inner teeth of the input steel gear 2, the second-stage outer teeth 12 of the flexible gear 1 are meshed with inner teeth of the output steel gear 3, the wave generator 4 is fixedly connected with an input shaft of a motor through a key, the input steel gear 2 is fixedly connected to a base of the double-arc curved surface harmonic transmission speed reducer, the output steel gear 3 is fixedly connected with an output shaft, and torque is transmitted through the output shaft to realize speed reduction; the first-stage external teeth 11 and the second-stage external teeth 12 are distributed on the same reference circle, and have different tooth numbers and different modulus.

Specifically, when the input shaft of motor high-speed operation, the input shaft drives wave generator 4 rotatory, make flexbile gear 1 that has the double-arc curved surface profile of tooth produce the deformation and rotate, first order external tooth 11 on the flexbile gear 1 and the internal tooth meshing of input steel wheel 2 carry out the staggered teeth motion, realize one-level harmonic speed reduction, simultaneously, the second level external tooth 12 of flexbile gear 1 opposite side carries out the deformation rotation equally, second level external tooth 12 produces the staggered teeth motion with output steel wheel 3, through the output shaft transmission moment of torsion that output steel wheel 3 is connected, realize second harmonic speed reduction. The flexible gear 1, the input steel gear 2 and the output steel gear 3 adopt double-arc curved surfaces

The speed ratio of the double-arc curved surface harmonic drive speed reducer is that i is the total speed ratio, and i = i₁（i₂+1）/（i₁ -i₂），Z_{Rou 1}Number of teeth of first-stage external teeth 11, i₁At a first speed ratio, i₁= Z_{Rou 1}/2 ；Z_{Rou 2}Number of teeth of second-stage external teeth 12, i₂At a second speed ratio, i₂= Z_{Rou 2}/2 。

The reference circle d = mz of the flexible gear 1, d is the diameter of the reference circle, m is the modulus, and Z is the number of teeth.

The utility model provides a first order external tooth 11 distributes on same pitch circle with second level external tooth 12, first order external tooth 11 is different with second level external tooth 12's modulus, the number of teeth is different, make flexbile gear 1 when meshing with input steel wheel 2 and output steel wheel 3, realize the two-stage speed reduction of harmonic through the deformation ripples of difference, can change two-stage tooth number difference and speed ratio difference in the great range, reach the purpose that the velocity ratio of harmonic speed reducer ware diminishes, satisfy the velocity ratio promptly and in 300 ability of honour 900 scopes.

In one embodiment, the first-stage external teeth 11, Z of the flexspline 1 are set for a reference circle d =100 of a double-arc-surface harmonic drive reducer_{Rou 1}=250, flexspline 1 second stage external teeth 12, Z i₂=200, then i₁= Z soft 1/2=125, m₁= d/Z_{Rou 1}=0.4，i₂= Z_{Rou 2}(ii)/2 =100, m2= d/zrou 2=0.5, i =125 × (100 + 1)/(125-100) = 505.

As shown in fig. 2, the overall meshing of the first-stage external teeth 11 of the flexspline 1 and the input steel wheel 2 is schematically shown.

As shown in fig. 3, the partial meshing of the first-stage external teeth 11 of the flexible gear 1 and the input steel gear 2 is shown, and an enlarged view of the meshing process of the tooth profile of the first-stage external teeth 11 and the tooth profile of the input steel gear 2 can be seen.

The input steel wheel 2 is fixedly connected to the base, the number of teeth of the first-stage external teeth 11 is smaller than that of the input steel wheel 2, and first-stage speed reduction transmission can be achieved; the number of teeth of the second-stage outer teeth 12 is smaller than that of the output steel wheel 3, and two-stage speed reduction transmission can be achieved, so that harmonic transmission speed reduction of the speed reducer is achieved.

The tooth profiles of the first-stage external teeth 11 and the second-stage external teeth 12 of the facility example are involute tooth profiles, and tooth crests and tooth roots of the involute tooth profiles are arc transitions 13. The circular arc transition 13 can prevent the first-stage external tooth 11 on the flexible gear 1 from being in the process of being nibbled by the input steel gear 2 and the tooth profile interference phenomenon of the second-stage external tooth 12 in the process of being nibbled by the output steel gear 3, so that the noise of the double-arc curved surface harmonic transmission speed reducer is reduced, the bearing capacity is improved, the transmission precision is improved, and the service life is prolonged.

The addendum arc radius of the first-stage external teeth 11 and the modulus ratio thereof, and the addendum arc radius of the second-stage external teeth 12 and the modulus ratio thereof are both 0.2-0.3.

In order to avoid tooth crest interference in the processes of engagement and disengagement, improve the meshing smoothness of the flexible gear 1, the input steel gear 2 and the output steel gear 3 and reduce the meshing noise, the ratio of the tooth root circular arc radius of the first-stage external teeth 11 to the modulus thereof is 0.3-0.5; the ratio of the root arc radius of the second-stage external teeth 12 to the modulus thereof is 0.3 to 0.5.

Stress concentration is avoided, the possibility of tooth root fracture is reduced, the bearing capacity is improved, and the ratio of the tooth crest arc radius of the first-stage external tooth 11 to the tooth root arc radius is 1.2-1.3; the ratio of the addendum arc radius of the second-stage external tooth 12 to the dedendum arc radius thereof is 1.2-1.3.

In order to ensure good meshing between the first-stage external teeth 11 and the input steel wheel 2 and between the second-stage external teeth 12 and the output steel wheel 3 and reduce the volume of the flexible gear 1, the tooth width of the first-stage external teeth 11 is 1-2mm smaller than that of the input steel wheel 2, and the tooth width of the second-stage external teeth 12 is 1-2mm smaller than that of the output steel wheel 3

In order to improve the number of the meshing teeth when the first-stage external teeth 11 are completely meshed with the input steel wheel 2 and the number of the meshing teeth when the second-stage external teeth 12 are completely meshed with the output steel wheel 3 and increase the bearing capacity of the speed reducer, the ratio of the meshing depth when the first-stage external teeth 11 are completely meshed with the input steel wheel 2 to the modulus of the first-stage external teeth 11 and the ratio of the meshing depth when the second-stage external teeth 12 are completely meshed with the output steel wheel 3 to the modulus of the second-stage external teeth 12 are both 1.1-1.3.

The flexible gear 1 with the double-arc curved surface tooth profile adopts the arc transition 13 at the tooth top and the tooth root, is suitable for the double-arc curved surface harmonic transmission speed reducer with compact structure, is convenient to process, the flexible gear 1 adopts the arc tooth profile, the wave height is also reduced, the wave height can be reduced, the meshing tooth number of the first-stage external teeth 11 of the flexible gear 1 and the input and rigid gears can be improved, the tooth root stress is reduced, the requirements on the material and the heat treatment are correspondingly reduced, the manufacturing cost can be reduced, the fatigue life of the flexible gear 1 is prolonged, and therefore the bearing capacity of the speed reducer is improved

On the other hand, the flexible gear 1 adopts a circular arc tooth shape, the wave height is also reduced, the reduction of the wave height can improve the number of meshing teeth of the first-stage external teeth 11 of the flexible gear 1 and the input and rigid gears, reduce the tooth root stress, correspondingly reduce the requirements on the material and the heat treatment of the flexible gear, reduce the manufacturing cost, prolong the fatigue life of the flexible gear 1, and further increase the bearing capacity of the speed reducer.

The embodiments of the present invention are preferred embodiments of the present application, and the scope of protection of the present application is not limited by the embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.