阅读说明：本技术 一种提高多级行星减速器稳定性的方法和一种行星减速器 (Method for improving stability of multi-stage planetary reducer and planetary reducer ) 是由 张坤 许建忠 康少博 阮文浩 邵广军 张�浩 崔云翔 许俊伟 邢鹤琛 于 2019-12-09 设计创作，主要内容包括：本发明涉及传动装置技术领域,公开了一种提高多级行星减速器稳定性的方法和一种行星减速器,其中的方法是在上级行星轮系的行星架和下级行星轮系的行星轮之间安装有环形的推力盘,推力盘同轴固定套接在下级行星轮系的太阳轮的太阳轴部外侧,推力盘的一侧盘面用于和上级行星轮系的行星架相抵,推力盘的另一侧盘面用于和下级行星轮系的行星轮的端面相抵。本发明的方法实质上是在相关位置增加推力盘,推力盘可以避免零部件之间发生摩擦、干涉、碰撞等,可以平衡行星减速器的轴向波动特性,可以限制太阳轮、行星架等摆动,有效提高行星减速器的稳定性,降低零部件的磨损速度,延长行星减速器的使用寿命。(The invention relates to the technical field of transmission devices, and discloses a method for improving the stability of a multi-stage planetary reducer and a planetary reducer. The method of the invention is essentially to add the thrust disc at the relevant position, the thrust disc can avoid the friction, interference, collision and the like between the parts, the axial fluctuation characteristic of the planetary reducer can be balanced, the swing of the sun gear, the planet carrier and the like can be limited, the stability of the planetary reducer is effectively improved, the abrasion speed of the parts is reduced, and the service life of the planetary reducer is prolonged.)

1. A method for improving the stability of a multi-stage planetary reducer comprises an upper-stage planetary gear train and a lower-stage planetary gear train, wherein a planet carrier of the upper-stage planetary gear train and a planet carrier of the lower-stage planetary gear train are both single-arm planet carriers.

2. A method according to claim 1, wherein the sun shaft of the sun gear of the lower planetary gear set of the multistage planetary gear set passes through the carrier of the upper planetary gear set, and the method further comprises sandwiching a ball having a center passing through a revolution axis of the multistage planetary gear set between the sun gear of the upper planetary gear set and the sun shaft of the sun gear of the lower planetary gear set, the ball being positioned and supported on the sun gear of the upper planetary gear set or the sun shaft of the sun gear of the lower planetary gear set.

3. The method for improving the stability of a multi-stage planetary reducer according to claim 2, further comprising sandwiching a roller between the sun gear of the upper planetary gear train and the sun shaft of the sun gear of the lower planetary gear train, the axis of the roller being coaxial with the revolution axis of the multi-stage planetary reducer, the roller being adapted to abut against the roller, the roller being positionally supported on the sun gear of the upper planetary gear train, the roller being positionally supported on the sun shaft of the sun gear of the lower planetary gear train; or the ball bearing is positioned and supported on the sun shaft part of the sun gear of the lower-stage planetary gear train, and the roller is positioned and supported on the sun gear of the upper-stage planetary gear train.

4. A planetary reducer comprises a shell, a coaxial input shaft and an output shaft, wherein the input shaft is rotationally connected with the input end of the shell through a rolling bearing, and the output shaft is rotationally connected with the output end of the shell through the rolling bearing; the primary planetary gear train comprises a primary inner gear ring, a primary sun gear, a primary planet carrier, a plurality of primary planet shafts and a primary planet gear which is rotationally connected to the primary planet shafts; the secondary planetary gear train comprises a secondary inner gear ring, a secondary sun gear, a secondary planet carrier, a plurality of secondary planet shafts and a secondary planet gear which is rotationally connected to the secondary planet shafts; the three-stage planetary gear train comprises a three-stage inner gear ring, a three-stage sun gear, a three-stage planet carrier, a plurality of three-stage planet shafts and three-stage planet gears which are rotationally connected to the three-stage planet shafts; the four-stage planetary gear train comprises a four-stage inner gear ring, a four-stage sun gear, a four-stage planet carrier, a plurality of four-stage planet shafts and four-stage planet gears which are rotationally connected to the four-stage planet shafts; the first-stage inner gear ring, the second-stage inner gear ring, the third-stage inner gear ring and the fourth-stage inner gear ring are all fixed on the inner side of the shell; the first-stage sun gear is coaxially and fixedly connected with the input shaft, and the output shaft is coaxially and fixedly connected with the fourth-stage planet carrier; the first-stage planet carrier, the second-stage planet carrier and the third-stage planet carrier are single-arm planet carriers, and the fourth-stage planet carrier is a double-arm planet carrier; the secondary sun wheel comprises a secondary gear part and a secondary sun shaft part, and the secondary sun shaft part is coaxially connected with the primary planet carrier; the three-stage sun wheel comprises a three-stage gear part and a three-stage sun shaft part, and the three-stage sun shaft part is coaxially connected with the two-stage planet carrier; the four-stage sun gear comprises a four-stage gear part and a four-stage sun shaft part, and the four-stage sun shaft part is coaxially connected with the three-stage planet carrier; an annular first thrust disc is coaxially and fixedly sleeved on the outer side of the secondary sun shaft part, the first thrust disc is arranged between the primary planet carrier and the secondary planet gear, one side disc surface of the first thrust disc is used for abutting against the primary planet carrier, and the other side disc surface of the first thrust disc is used for abutting against the end surface of the secondary planet gear; annular second thrust disc has been cup jointed to tertiary sun axial region outside coaxial fixed, and the second thrust disc is arranged between second grade planet carrier and tertiary planet wheel, and one side quotation of second thrust disc is used for offseting with the second grade planet carrier, and the opposite side quotation of second thrust disc is used for offseting with the terminal surface of tertiary planet wheel.

5. The planetary reducer according to claim 4, wherein the output shaft penetrates through the fourth-stage planet carrier, a ball top is clamped between the output shaft and the fourth-stage sun gear, the ball top is coaxially fixed on the output shaft, and the arc-shaped surface of the ball top is used for abutting against the fourth-stage sun gear.

6. The planetary reducer according to claim 4, wherein an annular third thrust disc is sandwiched between the primary sun gear and the primary planet carrier, the third thrust disc is coaxially embedded in the primary planet carrier, and a disc surface on one side of the third thrust disc is exposed out of the primary planet carrier and is used for abutting against the primary sun gear.

7. The planetary reducer according to claim 4, wherein the fourth sun shaft portion passes through the third planet carrier, an annular fourth thrust disk is sandwiched between the third sun gear and the fourth sun shaft portion, the fourth thrust disk is coaxially embedded in the fourth sun shaft portion, a side disk surface of the fourth thrust disk is exposed out of the fourth sun shaft portion and is used for abutting against the third sun gear.

8. The planetary reducer according to claim 5, wherein the second-stage sun gear, the third-stage sun gear and the fourth-stage sun gear are provided with axial center through holes, a blocking disc for abutting against a ball top on the output shaft is coaxially embedded at one end of the fourth-stage sun gear close to the output shaft, and a through hole is formed in the blocking disc and is communicated with the axial center through hole in the fourth-stage sun gear.

9. The planetary reducer according to claim 4, wherein the secondary sun shaft portion passes through the primary planet carrier, and a first ball is sandwiched between the primary sun gear and the secondary sun shaft portion, the center of the first ball passes through the revolution axis of the planetary reducer, and the first ball is positioned and supported at the end of the primary sun gear or the end of the secondary sun shaft portion; the fourth-stage sun shaft part penetrates through the third-stage planet carrier, a third ball is clamped between the third-stage sun gear and the fourth-stage sun shaft part, the center of the third ball passes through the revolution axis of the planetary reducer, and the third ball is positioned and supported at the end part of the third-stage sun gear or the end part of the fourth-stage sun shaft part; fourth ball is clamped between the four-stage sun gear and the output shaft, the center of the fourth ball passes through the revolution axis of the planetary speed reducer, and the fourth ball is positioned and supported at the end part of the four-stage sun gear or the end part of the output shaft.

10. The planetary reducer according to claim 9, wherein the primary sun gear and the secondary sun shaft have a first roller interposed therebetween, the axis of the first roller is coaxial with the common axis of the planetary reducer, the first roller is adapted to abut against a first ball, the first ball is supported and positioned on the primary sun gear, the first roller is supported and positioned on the secondary sun shaft, or the first ball is supported and positioned on the secondary sun shaft, the first roller is supported and positioned on the primary sun gear; a third roller is clamped between the third-stage sun gear and the fourth-stage sun shaft part, the axis of the third roller is coaxial with the revolution axis of the planetary reducer, the third roller is used for abutting against a third ball, the third ball is positioned and supported on the third-stage sun gear, the third roller is positioned and supported on the fourth-stage sun shaft part, or the third ball is positioned and supported on the fourth-stage sun shaft part, and the third roller is positioned and supported on the third-stage sun gear; the fourth roller is clamped between the four-stage sun gear and the output shaft, the axis of the fourth roller is coaxial with the revolution axis of the planetary reducer, the fourth roller is used for abutting against the fourth ball, the fourth ball is positioned and supported on the four-stage sun gear, the fourth roller is positioned and supported on the output shaft, or the fourth ball is positioned and supported on the output shaft, and the fourth roller is positioned and supported on the four-stage sun gear.

Technical Field

The invention relates to the technical field of transmission devices, in particular to a method for improving the stability of a multi-stage planetary reducer and the planetary reducer.

Background

The planetary gear train is a coaxial transmission structure, namely the output axis and the input axis of the planetary gear train are overlapped. The planetary gear train mainly comprises a sun gear, a planet carrier, an inner gear ring and the like. The sun gear rotates around the central axis of the sun gear, and the straight line where the central axis of the sun gear is located forms a revolution axis of the planetary gear train. The planet wheels are uniformly distributed around the sun wheel, and besides rotating around the central axis of the planet wheels, the planet wheels also rotate around the central axis of the sun wheel, namely, rotate around the revolution axis of the planetary gear train. The rotation of a planet around its own central axis is generally referred to as the rotation of the planet, and the rotation of a planet around an axis of revolution is generally referred to as the revolution of the planet, just like the sun and planet in the solar system, hence the name.

Planetary gear trains are widely used in planetary gear reducers, which are common speed change mechanisms in the mechanical field, and many planetary gear reducers include a plurality of planetary gear trains, and the revolution axes of the planetary gear trains in the same planetary gear reducer are coaxial to form the revolution axis of the planetary gear reducer, that is, the output shaft and the input shaft of the planetary gear reducer are coaxial.

In most of the planetary reducers, the sun gear, the planet carrier and the planet gears are in a floating state, and are mutually related and restricted, the load-sharing characteristic and the operation form of the whole planetary reducer, the meshing state between the sun gear and the planet gears and the position of the planet carrier are influenced by the relation, and the factors determine the operation stability of the planetary reducer.

In order to improve the stability of the planetary gear reducer, a double-arm type carrier is generally adopted as a carrier in the planetary gear reducer. However, the adoption of the double-arm type planet carrier inevitably leads to the excessive complexity of the structure of the planetary gear trains, the volume and the mass of the planetary speed reducer are increased, and the cost is increased correspondingly.

In order to simplify the structure of the planetary gear set, reduce the volume and mass of the planetary gear set, and reduce the production cost, a single-arm type planet carrier is adopted in some planetary gear sets. However, when the planetary reducer with such a structure is operated, the sun gear, the planet gear and the planet carrier may generate a certain displacement in the axial direction, which may cause contact friction between the sun gear, the planet carrier, the planet gear and the planet shaft, and may cause mutual interference or collision of parts in severe cases, thereby causing the planetary reducer to fail to operate.

Disclosure of Invention

The invention provides a method for improving the stability of a multi-stage planetary reducer and the planetary reducer, aiming at overcoming the defects in the prior art.

The invention achieves the above object by the following technical solutions.

A method for improving the stability of a multi-stage planetary reducer comprises an upper-stage planetary gear train and a lower-stage planetary gear train, wherein a planet carrier of the upper-stage planetary gear train and a planet carrier of the lower-stage planetary gear train are both single-arm planet carriers.

The thrust disc used in this embodiment is typically subjected to a heat treatment process, such as carburizing and quenching, to improve wear resistance. A gap of 0.5-1 mm is reserved between one side disc surface of the thrust disc and a planet carrier of a superior planetary gear train, and a gap of 0.5-1 mm is reserved between the other side disc surface of the thrust disc and a planet gear of a subordinate planetary gear train. The planetary gear train in this scheme all adopts the single armed planet carrier, can reduce multistage planetary reducer's volume and quality like this, reduction in production cost simplifies the structure. The method of the scheme can improve the stability of the multi-stage planetary reducer and mainly shows the following aspects: the thrust disc separates a planet carrier of a superior planetary gear train from a planet wheel of a subordinate planetary gear train, so that the planet wheel of the subordinate planetary gear train and the planet carrier of the superior planetary gear train are prevented from generating axial movement and generating mutual friction, interference, collision and the like; the existing end face structure of the ball top abutting against the sun gear or the planet carrier balances the axial fluctuation characteristic of a multi-stage planetary reducer on the revolution axis of each planetary gear train, the ball top is used for abutting against the end face of the sun gear or the planet carrier and is equivalent to the contact of a point and a surface, a gap of 0.2-0.5 mm is reserved between the ball top and the end face of the sun gear or the planet carrier usually, if the gap of each gear part or other matched parts is larger due to processing errors and the like, the revolution axis of the sun gear, the planet carrier and the like is likely to have larger deflection angles, so that the stability is reduced, the accelerated wear can be caused after long-term use, and the service life is prolonged. The contact between the disc surface of the thrust disc and the planet wheel is surface-to-surface contact, the thrust disc is always limited on the whole revolution track of the planet wheel, and the contact position between the disc surface of the thrust disc and the planet wheel deviates from the revolution axis, so that the deflection angle of the revolution axis of the sun wheel, the planet carrier and the like can be ensured within a small range or even does not deflect, the thrust disc not only can balance the axial fluctuation characteristic of the multi-stage planetary reducer, but also can limit the swinging of the sun wheel, the planet carrier and the like, thereby effectively improving the stability of the multi-stage planetary reducer, reducing the abrasion speed of parts and prolonging the service life of the multi-stage planetary reducer; thirdly), the planet wheel is prevented from being separated from the shaft, so as to avoid accidents.

As a further improvement, the sun shaft portion of the sun gear of the lower planetary gear train of the multistage planetary gear reducer passes through the carrier of the upper planetary gear train, and the method further includes sandwiching a ball, the center of which passes through the revolution axis of the multistage planetary gear reducer, between the sun gear of the upper planetary gear train and the sun shaft portion of the sun gear of the lower planetary gear train, the ball being positionally supported on the sun gear of the upper planetary gear train or on the sun shaft portion of the sun gear of the lower planetary gear train. According to the scheme, the balls are added on the basis of adding the thrust disc in the multi-stage planetary speed reducer, the balls are substantially equivalent to be used for replacing a ball top in the prior art, the balls are used for abutting against a sun shaft part of a sun gear of a lower-stage planetary gear train or a sun gear of an upper-stage planetary gear train, and a reserved gap between the balls and the sun shaft part of the sun gear of the lower-stage planetary gear train or the sun gear of the upper-stage planetary gear train is generally smaller than reserved gaps on two sides of the thrust disc and generally ranges from 0.2 mm to 0.4 mm. Increase the ball and can further inject axial fluctuation range, further improve stability, the ball is batch production in addition, can directly purchase, and is with low costs, and the precision is more unified, and through thermal treatment, wear resistance is good, installs easily moreover.

As a further improvement, the method further comprises that a roller is clamped between the sun gear of the upper planetary gear train and the sun shaft of the sun gear of the lower planetary gear train, the axis of the roller is coaxial with the revolution axis of the multi-stage planetary reducer, the roller is used for abutting against the roller, the roller is positioned and supported on the sun gear of the upper planetary gear train, and the roller is positioned and supported on the sun shaft of the sun gear of the lower planetary gear train; or the ball bearing is positioned and supported on the sun shaft part of the sun gear of the lower-stage planetary gear train, and the roller is positioned and supported on the sun gear of the upper-stage planetary gear train. According to the scheme, the rollers are added on the basis of adding the balls in the multi-stage planetary reducer, and gaps of 0.2-0.4 mm are reserved between the rollers and the balls. The roller is used for abutting against the ball, when the sun gear of the upper-stage planetary gear train or the sun gear of the lower-stage planetary gear train generates axial displacement fluctuation in the axial direction, friction is generated between the ball and the roller, so that other parts do not need to be subjected to heat treatment, and the process cost is reduced. In addition, the roundness of the ball is high, the ball and the roller are produced in batches, the ball and the roller can be directly purchased, the cost is low, the precision is uniform, the wear resistance is good after heat treatment, the installation is easy, when friction is generated between the ball and the roller, the friction ratio is low, and the influence on the transmission efficiency of the multi-stage planetary reducer is small.

The invention also introduces a planetary reducer, which comprises a shell, a coaxial input shaft and an output shaft, wherein the input shaft is rotationally connected with the input end of the shell through a rolling bearing, the output shaft is rotationally connected with the output end of the shell through the rolling bearing, and the planetary reducer comprises a primary planetary gear train, a secondary planetary gear train, a tertiary planetary gear train and a quaternary planetary gear train; the primary planetary gear train comprises a primary inner gear ring, a primary sun gear, a primary planet carrier, a plurality of primary planet shafts and a primary planet gear which is rotationally connected to the primary planet shafts; the secondary planetary gear train comprises a secondary inner gear ring, a secondary sun gear, a secondary planet carrier, a plurality of secondary planet shafts and a secondary planet gear which is rotationally connected to the secondary planet shafts; the three-stage planetary gear train comprises a three-stage inner gear ring, a three-stage sun gear, a three-stage planet carrier, a plurality of three-stage planet shafts and three-stage planet gears which are rotationally connected to the three-stage planet shafts; the four-stage planetary gear train comprises a four-stage inner gear ring, a four-stage sun gear, a four-stage planet carrier, a plurality of four-stage planet shafts and four-stage planet gears which are rotationally connected to the four-stage planet shafts; the first-stage inner gear ring, the second-stage inner gear ring, the third-stage inner gear ring and the fourth-stage inner gear ring are all fixed on the inner side of the shell; the first-stage sun gear is coaxially and fixedly connected with the input shaft, and the output shaft is coaxially and fixedly connected with the fourth-stage planet carrier; the first-stage planet carrier, the second-stage planet carrier and the third-stage planet carrier are single-arm planet carriers, and the fourth-stage planet carrier is a double-arm planet carrier; the secondary sun wheel comprises a secondary gear part and a secondary sun shaft part, and the secondary sun shaft part is coaxially connected with the primary planet carrier; the three-stage sun wheel comprises a three-stage gear part and a three-stage sun shaft part, and the three-stage sun shaft part is coaxially connected with the two-stage planet carrier; the four-stage sun gear comprises a four-stage gear part and a four-stage sun shaft part, and the four-stage sun shaft part is coaxially connected with the three-stage planet carrier; an annular first thrust disc is coaxially and fixedly sleeved on the outer side of the secondary sun shaft part, the first thrust disc is arranged between the primary planet carrier and the secondary planet gear, one side disc surface of the first thrust disc is used for abutting against the primary planet carrier, and the other side disc surface of the first thrust disc is used for abutting against the end surface of the secondary planet gear; annular second thrust disc has been cup jointed to tertiary sun axial region outside coaxial fixed, and the second thrust disc is arranged between second grade planet carrier and tertiary planet wheel, and one side quotation of second thrust disc is used for offseting with the second grade planet carrier, and the opposite side quotation of second thrust disc is used for offseting with the terminal surface of tertiary planet wheel.

The one-level planet carrier, the second grade planet carrier and the third grade planet carrier of the planetary reducer of the scheme all adopt single-arm planet carrier, the four-level planet carrier adopts double-arm planet carrier, and through the form that this kind of single double-arm combines, both can provide sufficient output torque, can simplify planetary reducer's structure again, reduce planetary reducer's volume and quality, reduction in production cost. The primary planet carrier and the secondary planet carrier are separated by the first thrust disc, so that mutual friction, interference, collision and the like caused by axial movement of the secondary planet carrier and the primary planet carrier are avoided; separate second grade planet carrier and tertiary planet wheel through the second thrust dish, avoid tertiary planet wheel and secondary planet carrier etc. to produce axial displacement and take place mutual friction, interference, collision etc.. In addition, the first thrust disc and the second thrust disc can balance the axial fluctuation characteristic of the planetary reducer and can limit the swing of the second-stage sun gear, the first-stage planet carrier, the third-stage sun gear, the second-stage planet carrier and the like, so that the stability of the planetary reducer is effectively improved, the abrasion speed of parts is reduced, and the service life of the planetary reducer is prolonged. In addition, the secondary planet wheel and the tertiary planet wheel can be prevented from being separated from the secondary planet shaft and the secondary planet shaft respectively, so that accidents are avoided.

As an optimized structure form, the output shaft penetrates through the four-stage planet carrier, a ball top is clamped between the output shaft and the four-stage sun gear, the ball top is coaxially fixed on the output shaft, and the arc-shaped surface of the ball top is used for abutting against the four-stage sun gear. The axial fluctuation characteristic of the planetary reducer can be further balanced by adding the ball top, and the stability of the planetary reducer is improved.

As an optimized structure form, an annular third thrust disc is clamped between the primary sun gear and the primary planet carrier, the third thrust disc is coaxially embedded on the primary planet carrier, one side disc surface of the third thrust disc is exposed out of the primary planet carrier, and the disc surface is used for abutting against the primary sun gear. The third thrust disc has the effect similar to that of the first thrust disc and the second thrust disc, so that the first-stage sun gear and the first-stage planet carrier can be separated, the axial fluctuation characteristic of the planetary speed reducer can be further balanced, and the stability of the planetary speed reducer is improved.

As an optimized structure form, the four-stage sun shaft part penetrates through the three-stage planet carrier, an annular fourth thrust disc is clamped between the three-stage sun gear and the four-stage sun shaft part, the fourth thrust disc is coaxially embedded in the four-stage sun shaft part, one side disc surface of the fourth thrust disc is exposed out of the four-stage sun shaft part, and the disc surface is used for abutting against the three-stage sun gear. The effect of fourth thrust dish is similar to the effect of first thrust dish and second thrust dish, both can obstruct tertiary sun gear and level four sun gear, can further balance planetary reducer's axial fluctuation characteristic again, improves planetary reducer's stability.

As an optimized structure form, the second-stage sun gear, the third-stage sun gear and the fourth-stage sun gear are all provided with an axle center through hole, one end of the fourth-stage sun gear, which is close to the output shaft, is coaxially embedded with a blocking disc which is used for abutting against a ball top on the output shaft, and a through hole is formed in the blocking disc and is communicated with the axle center through hole in the fourth-stage sun gear.

As another optimized structure form, the secondary sun shaft part penetrates through the primary planet carrier, a first ball is clamped between the primary sun gear and the secondary sun shaft part, the center of the first ball passes through a revolution axis of the planetary speed reducer, and the first ball is positioned and supported at the end part of the primary sun gear or the end part of the secondary sun shaft part; the fourth-stage sun shaft part penetrates through the third-stage planet carrier, a third ball is clamped between the third-stage sun gear and the fourth-stage sun shaft part, the center of the third ball passes through the revolution axis of the planetary reducer, and the third ball is positioned and supported at the end part of the third-stage sun gear or the end part of the fourth-stage sun shaft part; fourth ball is clamped between the four-stage sun gear and the output shaft, the center of the fourth ball passes through the revolution axis of the planetary speed reducer, and the fourth ball is positioned and supported at the end part of the four-stage sun gear or the end part of the output shaft.

As an optimized structure form, a first roller is clamped between the primary sun gear and the secondary sun shaft part, the axis of the first roller is coaxial with the revolution axis of the planetary reducer, the first roller is used for abutting against a first ball, the first ball is positioned and supported on the primary sun gear, the first roller is positioned and supported on the secondary sun shaft part, or the first ball is positioned and supported on the secondary sun shaft part, and the first roller is positioned and supported on the primary sun gear; a third roller is clamped between the third-stage sun gear and the fourth-stage sun shaft part, the axis of the third roller is coaxial with the revolution axis of the planetary reducer, the third roller is used for abutting against a third ball, the third ball is positioned and supported on the third-stage sun gear, the third roller is positioned and supported on the fourth-stage sun shaft part, or the third ball is positioned and supported on the fourth-stage sun shaft part, and the third roller is positioned and supported on the third-stage sun gear; the fourth roller is clamped between the four-stage sun gear and the output shaft, the axis of the fourth roller is coaxial with the revolution axis of the planetary reducer, the fourth roller is used for abutting against the fourth ball, the fourth ball is positioned and supported on the four-stage sun gear, the fourth roller is positioned and supported on the output shaft, or the fourth ball is positioned and supported on the output shaft, and the fourth roller is positioned and supported on the four-stage sun gear.

Compared with the prior art, the invention mainly has the following beneficial effects: the thrust disc plays a role in separating parts, and mutual friction, interference, collision and the like among the parts are avoided; in addition, the thrust disc not only can balance the axial fluctuation characteristic of the planetary reducer, but also can limit the swinging of the sun gear, the planet carrier and the like, thereby effectively improving the stability of the planetary reducer, reducing the abrasion speed of parts and prolonging the service life of the planetary reducer; in addition, the thrust disc can avoid the planet wheel to break away from the axle to cause the accident.

Drawings

Fig. 1 is a partial sectional view schematically showing a multistage planetary reduction gear according to a first embodiment of the present invention.

Fig. 2 is a partial sectional view schematically showing a multistage planetary reduction gear according to a second embodiment of the present invention.

Fig. 3 is a partial sectional view schematically showing a multistage planetary reduction gear according to a third embodiment of the present invention.

Fig. 4 is a schematic sectional view of a planetary reducer according to a fourth embodiment of the present invention.

Fig. 5 is a schematic sectional view of a planetary reducer according to a fifth embodiment of the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The drawings are for illustrative purposes only and are not to be construed as limiting the patent.

In order to explain the embodiment more simply, some parts which are known to those skilled in the art in the drawings or description but are not relevant to the main content of the present invention will be omitted. In addition, some components in the drawings may be omitted, enlarged or reduced for convenience of description, but do not represent the size or the entire structure of an actual product.