CN112610673A

CN112610673A - Differential speed reducer

Info

Publication number: CN112610673A
Application number: CN202011522567.7A
Authority: CN
Inventors: 陈广明
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-21
Filing date: 2020-12-21
Publication date: 2021-04-06

Abstract

The invention discloses a differential speed reducer which comprises a shell, an input shaft, an output shaft, a primary planetary gear train consisting of a first driving wheel, a first planet wheel, a primary planet carrier and a first inner gear ring, and a secondary planetary gear train consisting of a second driving wheel, a second planet wheel, a secondary planet carrier and a second inner gear ring, wherein the first driving wheel is connected with the first planet wheel; the second driving wheel is coaxial with and fixedly connected with the first driving wheel, the second inner gear ring is fixedly connected with the first inner gear ring, the first-stage planet carrier is fixedly connected with the shell, and the second-stage planet carrier is connected with the output shaft; the first driving wheel is connected with the input shaft, and a small amount of tooth difference exists between the primary planetary gear train and the secondary planetary gear train, so that the second inner gear ring, the second driving wheel and the second planetary gear form tangential rotation, and the linear speed has a difference value. In the speed reducer, the second driving wheel, the second inner gear ring and the second planet wheel form differential speed reduction, the magnitude order increase of the reduction ratio of the second-stage planet can be realized, the size and the weight of the speed reducer can be greatly reduced, and the efficient speed reduction transmission can be realized due to the simple structure of the wheel train.

Description

Differential speed reducer

Technical Field

The invention relates to the technical field of planetary reduction equipment, in particular to a differential speed reducer.

Background

The reducer is widely applied to various fields of national economy, and relates to the industries of metallurgy, nonferrous metal, coal, building materials, ships, water conservancy, electric power, engineering machinery, petrifaction and the like.

The reducer is an independent part consisting of gears enclosed in a rigid casing, and is often used as a speed reduction transmission device between a prime mover and a working machine to reduce the rotating speed and improve the torque, and also can be used for transmitting the motion.

The product category comprises various gear reducers, planetary gear reducers and worm reducers, and also comprises various special transmission devices, such as speed increasing devices, speed adjusting devices, various composite transmission devices including flexible transmission devices and the like.

At present, the conventional gear reducer is mature in technology and simple in structure, but the following problems generally exist: (1) the maximum secondary planetary reduction ratio is not more than 100, and a large reduction ratio is difficult to realize; (2) the multistage straight gear or planetary gear reducer is bulky and low in efficiency.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a differential speed reducer so as to solve the problem that a straight gear speed reducer and a conventional planetary speed reducer are difficult to realize large speed reduction ratio.

The invention provides a differential speed reducer, which comprises a shell, an input shaft, an output shaft, a primary planetary gear train consisting of a first driving wheel, a first planet wheel, a primary planet carrier and a first inner gear ring, and a secondary planetary gear train consisting of a second driving wheel, a second planet wheel, a secondary planet carrier and a second inner gear ring; the second driving wheel and the first driving wheel are coaxial and rotate synchronously and then are connected with the input shaft; the second inner gear ring is fixedly connected with the first inner gear ring to form an integral component, the first-stage planet carrier is fixedly connected with the shell, the second-stage planet carrier is connected with the output shaft and used for realizing power output, the gear ratio of the first-stage planetary gear train is not equal to that of the second-stage planetary gear train, so that the second inner gear ring, the second driving wheel and the second planet wheel form differential tangential rotation, the second planet wheel rotates around the second driving wheel, and the second planet carrier drives the output shaft to rotate so as to realize a speed reduction function; the reduction ratio range of the differential speed reducer can be adjusted to be single digit to thousands of orders by changing the tooth number of the driving wheel I, the inner gear ring I, the driving wheel II and the inner gear ring II, and positive and negative rotation can be output by adjusting the positive and negative values of the gear difference.

Furthermore, the ratio of the gear ratio of the primary planetary gear train to the gear ratio of the secondary planetary gear train is set to be close to 1, and the gear difference multiplying power of the inner gear ring and the driving wheel is improved, so that the differential speed reducer can achieve a high transmission ratio.

Furthermore, the number of teeth of the first driving wheel and the number of teeth of the second driving wheel are both 25, the number of teeth of the second ring gear is 301, the number of teeth of the first ring gear is 299, and the transmission ratio of the differential speed reducer is 1/1949.48 at the moment.

Furthermore, the number of teeth of the first driving wheel and the number of teeth of the second driving wheel are both 25, the number of teeth of the second ring gear is 51, the number of teeth of the first ring gear is 49, and the transmission ratio of the differential speed reducer is 1/74.48 at this time.

Further, the number of teeth of the first driving wheel is 49, the number of teeth of the second driving wheel is 50, the number of teeth of the second ring gear is 200, the number of teeth of the first ring gear is 199, and at this time, the transmission ratio of the differential speed reducer is 1/331.67.

Further, the ratio of the gear ratio of the primary planetary gear train to the gear ratio of the secondary planetary gear train is set to be far from 1 to achieve a low gear ratio of the differential speed reducer.

Further, the number of teeth of the first driving wheel is 21, the number of teeth of the second driving wheel is 50, the number of teeth of the second ring gear is 100, the number of teeth of the first ring gear is 201, and at this time, the transmission ratio of the differential speed reducer is 1/3.78.

Furthermore, a rotary support is arranged on the inner sides of the second inner gear ring and the first inner gear ring and is in rotary connection with a central shaft where the first driving wheel is located.

Furthermore, the first planet wheel is provided with two to four, and the first planet wheels are respectively in rotating connection with the first-stage planet carrier.

Furthermore, the second planet wheel is provided with two to four, and the second planet wheels are respectively in rotating connection with the second-stage planet carrier.

Compared with the prior art, the differential speed reducer has the following beneficial effects: the gear ratio of the primary planetary gear train and the gear ratio of the secondary planetary gear train are designed to be close to but not equal to each other, so that the gear ring II, the driving wheel II and the planet wheel II form tangential rotation, the linear speeds have difference values, and the secondary planet carrier is connected with the output shaft, so that the magnitude order of the reduction ratio of the secondary planet is increased, and the purpose of high reduction ratio is achieved; by adopting the planetary gear differential speed reducing mechanism, the transmission elements can be reduced, the transmission efficiency is improved, and the volume and the weight of the whole speed reducer are greatly reduced; because the gear train structure is simple, the high-efficiency speed reduction transmission can be realized.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of the differential speed reducer of the present invention.

Description of the reference numerals

1. A first driving wheel; 2. a planet wheel I; 3. a first inner gear ring; 4. a second inner gear ring; 5. a planet wheel II; 6. a second driving wheel; 7. a primary planet carrier; 8. a secondary planet carrier; 9. a housing: 10. and (4) a rotating bracket.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

Fig. 1-illustrates some embodiments according to the invention.

As shown in fig. 1, a differential speed reducer includes a housing 9, an input shaft n1, an output shaft n8, and a two-stage planetary speed reducing mechanism disposed inside the housing, the two-stage planetary speed reducing mechanism including a primary planetary gear train including a primary driving wheel one 1, a planetary gear one 2, a primary planetary carrier 7, and an annular gear one 3; the secondary planetary gear train comprises a driving wheel II 6, a planetary wheel II 5, a secondary planet carrier 8 and an annular gear II 4.

As shown in fig. 1, a first driving wheel 1 and a first inner gear ring 3 are respectively engaged with a first planet wheel 2, the first planet wheel 2 is rotatably connected with a first-stage planet carrier 7, and the first-stage planet carrier 7 is fixedly connected with a shell 9; the driving wheel I1 is connected with the input shaft, so that the inner gear ring I3 can be driven to rotate, and a primary speed reduction function is realized.

As shown in fig. 1, the second driving wheel 6 is coaxial and fixedly connected with the first driving wheel 1; the inner gear ring II 4 is fixedly connected with the inner gear ring I3, the inner sides of the inner gear ring II and the inner gear ring I are provided with a rotary support 10, and the rotary support 10 is rotationally connected with a central shaft where the driving wheel I1 is located; the driving wheel II 6 and the annular gear II 4 are respectively meshed with the planet wheel II 5, and the planet wheel II 5 is rotatably arranged on the secondary planet carrier 8.

The number of the planet wheels I2 is two to four, and the planet wheels I2 are respectively in rotating connection with the primary planet carrier 7; the number of the second planet wheels 5 is two to four, and the plurality of second planet wheels 5 are respectively in rotary connection with the secondary planet carrier 8; the planet wheels I2 and the planet wheels II 5 are arranged, so that the running stability of the two-stage planetary reduction mechanism can be improved.

In the process of designing the number of gear teeth in the two-stage planetary reduction mechanism, in order to achieve a large reduction ratio, the ratio of the gear ratio of the primary planetary gear train to the gear ratio of the secondary planetary gear train is set to be close to 1, and the gear difference multiplying power of the inner gear ring and the driving wheel is improved, so that the differential speed reducer achieves a high transmission ratio.

Specifically, the number of teeth of the first driving wheel 1 and the number of teeth of the second driving wheel 6 are designed to be the same, the number of teeth of the second inner gear ring 4 and the number of teeth of the first inner gear ring 3 are designed to be different by two teeth, or the number of teeth of the first driving wheel 1 and the number of teeth of the second driving wheel 6 are designed to be different by one tooth, the number of teeth of the second inner gear ring 4 and the number of teeth of the first inner gear ring 3 are designed to be different by one tooth, and the difference between the number of teeth of the first driving wheel 1 and the number of teeth of the first inner gear ring 3 is ensured to be.

Because the differential teeth of a plurality of gears in the two-stage planetary reduction mechanism are arranged, the gear ratio of the primary planetary gear train is close to but not equal to that of the secondary planetary gear train, so that a small difference exists between the linear speeds of the second driving wheel 6 and the second inner gear ring 4, the second inner gear ring 4 and the second driving wheel 6 form differential tangential rotation, the second planetary gear 5 can be driven to slowly rotate and circumferentially rotate around the second driving wheel 6, the second planetary gear 5 drives the second planetary carrier 8 to revolve around the second driving wheel 6, the second planetary carrier 8 is connected with the output shaft to form reduction torque output, and positive and negative rotation can be output by adjusting the positive and negative values of the gear difference.

Through the disclosed calculation formula of the transmission ratio of the planetary gear train, the calculation formula of the transmission ratio of the two-stage planetary differential speed reducing mechanism is derived as follows:

n8/n1＝(1-(Z1*Z4)/(Z3*Z6))/(1+Z4/Z6)。

in one embodiment, when the number of gear teeth in the two-stage planetary reduction mechanism is set, the number of teeth of the driving wheel one 1 and the driving wheel two 6 is set to 25, the number of teeth of the ring gear two 4 is set to 51, and the number of teeth of the ring gear one 3 is set to 49; the transmission ratio of the whole two-stage planetary speed reducing mechanism can be calculated to be 1/74.48, namely the first driving wheel 1 and the second driving wheel 6 rotate in 74 circles in the circumferential direction, the second planet wheel 5 and the second-stage planet carrier 8 rotate in one circle, namely the rotation speed of the input shaft is equal to 74 times of the rotation speed of the output shaft.

In one embodiment, the number of teeth of the first driving wheel 1 is set to 49, the number of teeth of the second driving wheel 6 is set to 50, the number of teeth of the second ring gear 4 is set to 200, and the number of teeth of the first ring gear 3 is set to 199; at this time, the transmission ratio of the whole two-stage star speed reducing mechanism can reach 1/331.67, namely the speed of the input shaft is approximately equal to 332 times of the speed of the output shaft, and a very large transmission ratio is achieved.

In one embodiment, when the number of teeth of the driving wheel one 1 is set to 25, the number of teeth of the driving wheel two 6 is set to 25, the number of teeth of the ring gear two 4 is set to 301, and the number of teeth of the ring gear one 3 is set to 299; at this time, the transmission ratio of the whole two-stage star speed reducing mechanism can reach 1/1949.48, namely the speed of the input shaft is equal to 1949 times of the speed of the output shaft, and the transmission ratio of the planetary speed reducer far exceeds that of most three-stage speed reduction boxes.

In one embodiment, when the number of teeth of the gears in the two-stage planetary reduction mechanism is designed, the ratio of the transmission ratio of the first-stage planetary gear train to the transmission ratio of the second-stage planetary gear train is set to be far from 1, so that the differential speed reducer achieves a low transmission ratio.

Specifically, the number of teeth of the first driving wheel 1 is set to 21, the number of teeth of the second driving wheel 6 is set to 50, the number of teeth of the second inner gear ring 4 is set to 50, and the number of teeth of the first inner gear ring 3 is set to 201; at the moment, the transmission ratio of the whole two-stage planetary reduction mechanism can reach 1/3.78, namely the rotating speed of the input shaft is approximately equal to 4 times of the rotating speed of the output shaft, and the transmission ratio reaches very low, has no use value and can be directly completed by using a one-stage planetary gear train.

The differential speed reducer of the invention works as follows:

the first driving wheel 1 and the second driving wheel 6 are driven to rotate forwards through the input shaft, the first driving wheel 1 drives the first planet wheel 2 and the first inner gear ring 3 to rotate reversely, the first inner gear ring 3 drives the second inner gear ring 4 to rotate reversely synchronously, and because the gear teeth of the first-stage planetary gear train and the second-stage planetary gear train have a small gear difference, the linear speeds of the second inner gear ring 4 and the second driving wheel 6 have a small difference value, the second planet wheel 5 is driven to rotate axially around the second driving wheel 6, the second planet wheel 5 drives the second planet carrier 8 to rotate around the second driving wheel 6, and the second planet carrier 8 drives the output shaft to output.

The differential speed reducer of the present invention has the following advantages in addition to the above-described advantageous effects:

1. compact structure, compare with three level spur gear speed reducer of tradition, volume and weight all can reduce about half than traditional speed reducer, and is small, light in weight.

2. The transmission ratio is large, the reduction ratio of a traditional three-level straight gear reducer is generally about 100, the transmission ratio of a traditional two-level planetary reducer is generally about 50-100, the transmission ratio of the differential reducer can reach more than 1000, and the large reduction ratio of 1000 orders of magnitude is easily realized.

3. The transmission is stable and accurate, and because the transmission return difference of the planetary gear is small, the tooth side clearance is adjustable, the transmission is stable, the precision is high, and the impact is small; meanwhile, the gear train has large meshing proportion and low tooth surface relative slip speed, and can realize heavy-load transmission.

4. The operation is safe and efficient, the whole transmission efficiency is high, the high-speed rotating pieces are all arranged in the device, the structure is safe and reliable in operation, and the operation noise is low.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A differential reducer, comprising:

the planetary gear train comprises a shell (9), an input shaft, an output shaft, a primary planetary gear train consisting of a first driving wheel (1), a first planet wheel (2), a primary planet carrier (7) and a first inner gear ring (3), and a secondary planetary gear train consisting of a second driving wheel (6), a second planet wheel (5), a secondary planet carrier (8) and a second inner gear ring (4);

the second driving wheel (6) and the first driving wheel (1) are coaxial and rotate synchronously, and then are connected with the input shaft; the inner gear ring II (4) is fixedly connected with the inner gear ring I (3) to form an integral component, the primary planet carrier (7) is fixedly connected with the shell (9), the secondary planet carrier (8) is connected with the output shaft to realize power output,

the gear ratio of the primary planetary gear train is not equal to that of the secondary planetary gear train, so that the inner gear ring II (4), the driving wheel II (6) and the planet wheel II (5) form differential tangential rotation, the planet wheel II (5) revolves around the driving wheel II (6) and drives the output shaft to rotate, and the speed reduction function is realized; the reduction ratio range of the differential speed reducer can be adjusted to be single digit to thousands of orders by changing the tooth numbers of the driving wheel I (1), the inner gear ring I (3), the driving wheel II (6) and the inner gear ring II (4), and positive and negative rotation can be output by adjusting the positive and negative values of the gear difference.

2. The differential speed reducer according to claim 1, wherein the ratio of the gear ratio of the primary planetary gear train to the gear ratio of the secondary planetary gear train is set close to 1, and the gear difference magnification of the ring gear and the drive gear is increased to achieve a high gear ratio of the differential speed reducer.

3. A differential speed reducer according to claim 2, wherein the number of teeth of the first driving wheel (1) and the number of teeth of the second driving wheel (6) are both 25, the number of teeth of the second ring gear (4) is 301, the number of teeth of the first ring gear (3) is 299, and the transmission ratio of the differential speed reducer is 1/1949.48.

4. A differential reducer according to claim 2, wherein the number of teeth of the first driving wheel (1) is 49, the number of teeth of the second driving wheel (6) is 50, the number of teeth of the second ring gear (4) is 200, and the number of teeth of the first ring gear (3) is 199, so that the transmission ratio of the differential reducer is 1/331.67.

5. A differential reducer according to claim 2, wherein the number of teeth of the first driving wheel (1) and the number of teeth of the second driving wheel (6) are both 25, the number of teeth of the second ring gear (4) is 51, and the number of teeth of the first ring gear (3) is 49, so that the transmission ratio of the differential reducer is 1/74.48.

6. A differential speed reducer according to claim 1, wherein the ratio of the gear ratio of the primary planetary gear train to the gear ratio of the secondary planetary gear train is set to be far from 1 to achieve a low gear ratio of the differential speed reducer.

7. A differential reducer according to claim 6, wherein the number of teeth of the first driving wheel (1) is 21, the number of teeth of the second driving wheel (6) is 50, the number of teeth of the second ring gear (4) is 100, and the number of teeth of the first ring gear (3) is 201, so that the transmission ratio of the differential reducer is 1/3.78.

8. A differential speed reducer according to claim 1, characterized in that the inner sides of the second ring gear (4) and the first ring gear (3) are provided with a rotary support (10), and the rotary support (10) is rotatably connected with a central shaft on which the first driving wheel (1) is located.

9. A differential reducer according to claim 1, in which there are two to four planet wheels one (2), and a plurality of planet wheels one (2) are each rotatably connected to the primary planet carrier (7).

10. A differential reducer according to claim 1, in which there are two to four planet wheels (5), and a plurality of the planet wheels (5) are each rotationally connected to the secondary planet carrier (8).