A planetary gear reducer with double inputs and double outputs

Abstract

A planetary gear reducer with double inputs and double outputs is provided with a housing. Inside the housing, three planetary gear trains are arranged in sequence from left to right. The first planetary gear train includes an input sleeve, a first internal gear ring frame, a first internal gear ring, an input planetary carrier, a first planetary gear, and a central gear shaft. The input sleeve is connected to the first internal gear ring through the first internal gear ring frame. The first planetary gear is installed on the input planetary carrier and meshes with the first internal gear ring and the central gear shaft respectively. The second planetary gear train includes a central gear and planetary gear shafts. The central gear is connected to the output end of the central gear shaft and meshes with multiple planetary gear shafts that do not revolve around the sun. The third planetary gear train includes a second planetary gear, a second internal gear ring, a second internal gear ring frame, and an output sleeve. The right end of the planetary gear shaft is connected to a second planetary gear that meshes with the second internal gear ring. The second internal gear ring is connected to the output sleeve through the second internal gear ring frame. This reducer improves the stability, transmission accuracy, and reduction ratio of the reducer within a limited space.

Description

Technical Field

[0001] The present invention relates to the technical field of speed reducers, and specifically relates to a planetary gear speed reducer with double inputs and double outputs. Background Art

[0002] Planetary speed reducers have the advantages of small mass, small volume, large transmission ratio and high efficiency. Therefore, planetary gear transmission has now been widely used in various fields such as construction machinery, mining machinery, machine tools, robots, and automobiles. Planetary speed reducers are not only suitable for high speeds and high powers, but also have been applied to transmission devices with low speeds and large torques. It can be applied to almost all powers and application ranges.

[0003] Generally, speed reducers are single-input and single-output. When a higher transmission ratio is required, it is difficult to ensure the transmission efficiency and the strength of the speed reducer. By making full use of the characteristics of planetary gear speed reducers, a double-input and double-output planetary speed reducer for specific occasions is designed.

[0004] At present, there are already designs of double-input and double-output planetary speed reducers, but the transmission efficiency is not high enough, the size is too large, and the stability of the speed reducer needs to be improved. For example, the invention with the application number 201911277679.8 provides a single / double-input and double-output planetary gear speed reducer, which includes a housing, and two sets of input gear systems, two sets of planetary rotation systems and two sets of output systems installed in the inner cavity of the housing. Two fixed sun gears are fixedly connected together to form the body part of the speed reducer. The rotating sun gears are supported on their respective fixed sun gears through bearings. The planetary gear mechanism is installed on the planet carrier and can make planetary rotation around the axis of the speed reducer. This product uses a gear shaft to provide power for the planetary system. It can be directly seen from its assembly drawing that the left input gear shaft is relatively long, and its length is almost four-fifths of the length of the speed reducer, which will cause higher vibration and it is very difficult to ensure stability. There are two sets of planetary rotation systems in this product, and the two sets of planetary systems are not linked, and the planetary structure is simple, with a small transmission ratio, which needs to be improved. The two input ends of this product are on the same axis, distributed on the left and right sides of the speed reducer, and are fixedly connected or in clearance fit. In this way, when inputting simultaneously, the requirements for the input source are relatively high. When the rotational speeds are inconsistent, it will generate a large torque or vibration, and even damage the input shaft. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a planetary gear speed reducer with double inputs and double outputs, which improves the stability, transmission accuracy and reduction ratio of the speed reducer within a limited space.

[0006] To achieve the above technical objectives, the technical solution adopted is: a planetary gear reducer with double input and double output, provided with a housing, and three planetary gear trains are sequentially arranged in the housing from left to right. The first planetary gear train includes an input sleeve, a first internal gear ring frame, a first internal gear ring, an input planetary carrier, a first planetary gear and a central shaft. The input sleeve is coaxially connected to the first internal gear ring through the first internal gear ring frame. A plurality of first planetary gears with the same parameters are installed on the input planetary carrier. A plurality of first planetary gears are respectively meshed with the left end of the first internal gear ring and the central shaft. The right end of the central shaft is the output end. The second planetary gear train includes a central gear and a planetary gear shaft. The central gear is connected to the output end of the central shaft. The outer circle of the central gear meshes with a plurality of planetary gear shafts that do not revolve around the sun. The third planetary gear train includes a second planetary gear, a second internal gear ring, a second internal gear ring frame and an output sleeve. The right end of each planetary gear shaft is connected to a second planetary gear. A plurality of second planetary gears are meshed with the outer second internal gear ring. The second internal gear ring is connected to the output sleeve through the second internal gear ring frame. The output sleeve is coaxially arranged with the central shaft.

[0007] The number of the first planetary gears described in the present invention is four.

[0008] The input planetary carrier described in the present invention is connected to the first planetary gear through a connecting shaft. The right side of the connecting shaft is tangent to the inner hole of the first planetary gear and passes through the center of the first planetary gear and then is connected to a first baffle to prevent the first planetary gear from axially moving.

[0009] A first bearing and a fifth sleeve are sleeved on the left end of the central shaft described in the present invention. A step for axially limiting the first bearing is provided in the input planetary carrier corresponding to the left side of the first bearing, and the right side is limited by the fifth sleeve. The outer circle of the first bearing is tangent to the inner hole of the input planetary carrier, and the inner hole of the first bearing is tangent to the outer circle of the left end of the central shaft.

[0010] The beneficial effects of the present invention are:

[0011] The reducer adopts three planetary gear trains to drive sequentially, with a high transmission ratio. And this structure gives full play to the advantages of planetary gear transmission. Based on the principle of planetary gear transmission, it ensures the correctness of the transmission theory of the reducer and the feasibility of the transmission scheme. At the same time, it brings great convenience to the processing of each component. Through indirect driving of the first internal gear ring and direct driving of the input planetary carrier for linkage input, the structure between the two is more compact, making the transmission more accurate. The double input enables the reducer to have a higher reduction ratio in a limited space. The central shaft of the reducer is both the output shaft and drives the central gear of the second module, making the reducer have high transmission efficiency, good stability, high precision and a smaller volume.

[0012] The key components of the present invention are basically rotors. The connection between components is relatively compact, making rational use of space and giving full play to the structural characteristics of the planetary reducer, resulting in a small volume of the reducer. And through ingenious design, the bearings are fixed by the steps of the components themselves, reducing the number of parts and saving processing costs.

[0013] As Figure 2 shown, there are four planetary gears in the planetary gear structure of the first module of the present invention, increasing the torque strength and having a stronger load-bearing capacity. In the 2Z-X planetary transmission with double planetary gears, in order to facilitate installation, generally the number of teeth of the sun gear and the internal gear ring is an integer multiple of the number of planetary gears. However, in the first module, the four planetary gears are not an integer multiple of the number of teeth of the sun gear and the internal gear ring, so they cannot be evenly distributed. By using 3D software to assist in measuring the relative positions between the four planetary gears, the transmission of the reducer is made more accurate, while facilitating processing and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic cross-sectional structure diagram of the present invention;

[0015] Figure 2 is Figure 1 the hole position diagram of the non-uniformly distributed holes of the first planetary gear train in

[0016] Figure 3 the principle schematic diagram of the present invention;

[0017] In the figure: 1 - first bolt, 2 - left cover plate, 3 - planetary carrier cover plate, 4 - first sealing ring, 5 - second sealing ring, 6 - second bolt, 7 - third sealing ring, 8 - input sleeve, 9 - input planetary carrier, 10 - first bearing, 11 - nut, 12 - second bearing, 13 - first internal gear ring carrier, 14 - third bearing, 15 - bearing seat, 16 - first sleeve, 17 - box body, 18 - first fixing key, 19 - first internal gear ring, 20 - first planetary gear, 21 - needle roller bearing, 22 - connecting shaft, 23 - first baffle, 24 - flat head screw, 25 - planetary gear shaft, 26 - second sleeve 2, 27 - central gear, 28 - fourth bearing, 29 - third sleeve, 30 - bearing cover plate, 31 - fourth sleeve, 32 - second internal gear ring, 33 - second fixing key, 34 - second planetary gear, 35 - second baffle, 36 - second internal gear ring carrier, 37 - right end cover, 38 - screw, 39 - fourth sealing ring, 40 - output sleeve, 41 - third baffle, 42 - fifth sealing ring, 43 - fifth bearing, 44 - fifth sleeve, 45 - central gear shaft, 46 - round nut, 47 - gasket, 48 - key block, 49 - fourth bolt, 50 - sixth bearing. DETAILED DESCRIPTION OF THE INVENTION

[0018] The following provides a preferred embodiment of the invention in conjunction with the accompanying drawings to elaborate in detail on the technical solution of the present invention. Here, corresponding drawings will be given to explain the present invention in detail. It should be particularly noted that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not used to limit or define the present invention.

[0019] In the description of this embodiment, the orientation or positional relationships indicated by terms such as "inner", "outer", "front", "rear", "left", "right", etc. are all based on the orientation or positional relationships shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element 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. In addition, terms such as "first", "second", etc. are only used to distinguish similar objects and cannot be understood as a specific order or sequence. It should be understood that such use can be interchanged under appropriate circumstances.

[0020] As Figure 1 shown, a planetary gear reducer with double inputs and double outputs is provided with a housing. Inside the housing, three planetary gear trains are arranged from left to right. The housing is composed of a box body 17, a bearing seat 15, a left cover plate 2, and a right cover plate 37. The left cover plate 2 and the right cover plate 37 are connected to the box body 17 through the first bolt 1 and the bearing seat 15.

[0021] As Figure 3 shown, the first planetary gear train includes an input sleeve 8, a central gear shaft 45, a first internal gear ring 19, a first internal gear ring frame 13, and an input planetary carrier 9. The second planetary gear train includes a central gear 27 and a planetary gear shaft 25. The third planetary gear train includes a second planetary gear 4, a second internal gear ring 32, a second internal gear ring frame 36, and an output sleeve 40. Four holes are evenly distributed inside the box body 17 to fix the four planetary gear shafts 25 so that they do not revolve.

[0022] The input sleeve 8 of the first planetary gear train is one of the input ends and is provided with a keyway for connection with the motor. The input sleeve 8 is connected to the first internal gear ring frame 13 through eight second bolts 6. Two third bearings 14 are sleeved on the outer cylindrical surface where the input sleeve 8 is connected to the first internal gear ring frame 13. The inner hole of the third bearing 14 is tangent to the first internal gear ring frame 13 and the input sleeve 8, and the outer circle of the third bearing 14 is tangent to the left bearing seat 15. A second bearing 2 is installed between the first internal gear ring frame 13 and the input planetary carrier 9.

[0023] The first internal gear ring frame 13 is connected to the first internal gear ring 19 through the first bolt 1 and the first fixing key 18 to drive the first internal gear ring 19 to move. Engaged with the first internal gear ring 19 are four first planetary gears 20 with the same gear parameters.

[0024] A plurality of first planet gears 20 with the same parameters are installed on the input planet carrier 9. When installing, bearings and a connecting shaft can be used. Specifically, there is a step inside the first planet gear 20 to position the needle roller bearing 21 of the first planet gear 20. The outer circle of the needle roller bearing 21 is tangent to the inner hole of the first planet gear 20, and the inner hole of the needle roller bearing 21 is tangent to the outer circle of the right side of the connecting shaft 22. The input planet carrier 9 is connected to the first planet gear 20 through the connecting shaft 22. The outer circle of the left side of the connecting shaft 22 is tangent to four non-uniformly distributed inner holes of the input planet carrier 9. A first sleeve 16 is installed on the left side of the connecting shaft 22. A first baffle 23 for limiting the first planet gear 20 is provided on the right side of the connecting shaft 22. The first baffle 23 is connected to the connecting shaft 22 through a countersunk bolt to fix the planet gear and prevent its axial movement.

[0025] The sun gear shaft 45 is a gear shaft. The left side of the gear shaft has two gears with the same gear parameters. Four first planet gears 20 are meshed with the left section of the sun gear shaft 45. The right end of the sun gear shaft 45 is one of the output ends. The sun gear shaft 45 is both an output end and uses the other section of the left end gear to drive the sun gear 27. There is a gear groove inside the sun gear 27, which is sleeved on the left end of the sun gear shaft 45. The outer circle of the leftmost end of the sun gear shaft 45 is tangent to the inner hole of the first bearing 10. The outer circle of the first bearing 10 is tangent to the inner hole of the right end of the input planet carrier 9. There is a step for axial limit of the first bearing 10 inside the input planet carrier 9. Using the step reduces the use of limit parts. A fifth sleeve 44 sleeved on the sun gear shaft 45 is provided on the right side of the first bearing 10. The first bearing 10 plays a role in supporting the sun gear shaft 45 and assisting in output.

[0026] There are also four planetary gear shafts 25 meshed with the sun gear 27. The planetary gear shafts 25 are evenly distributed in four inner holes of the housing 17, and their positions are fixed by the housing 17. There are two fourth bearings 28 in the middle of the planetary gear shaft 25. The outer circle of the fourth bearing 28 is tangent to the inner hole of the housing 17, and the inner hole of the fourth bearing 28 is tangent to the outer circle of the planetary gear shaft 25. The fourth bearing 28 is positioned by the second sleeve 26, the third sleeve 29, and the fourth sleeve 31. A bearing cover plate 30 is also provided on the right side of the middle of the planetary gear shaft 25. The bearing cover plate 30 is fixed to the side wall of the inner hole of the housing 17 by eight bolts. There is a keyway at the right end of the planetary gear shaft 25 for connecting with the second planet gear 34.

[0027] There is a second baffle 35 at the right end of the four second planet gears 34. The second baffle 35 is fixed to the planetary gear shaft 25 through a countersunk bolt. The four second planet gears 34 are meshed with the second internal gear ring 32. The second internal gear ring 32 is connected to the second internal gear ring frame 36 through the second fixing key 33 and the fourth bolt 49. The second internal gear ring 32 drives the second internal gear ring frame 36 to rotate.

[0028] There is a fifth bearing 43 between the second internal gear ring frame 36 and the central gear shaft 45. The fifth bearing 43 is fixed by a round nut 46 and a third baffle 41 on the central gear shaft 45. There are two sixth bearings 50 between the second internal gear ring frame 36 and the right-end bearing seat. The outer circle of the sixth bearing 50 is tangent to the inner hole of the right-end bearing seat, and the inner hole of the sixth bearing 50 is tangent to the outer circle at the right end of the second internal gear ring frame 36. There are protruding blocks in the right-end bearing seat to separate the two sixth bearings. There is a step on the second internal gear ring frame 36 to fix the sixth bearing on the left side. The output sleeve 40 is fixed to the left side of the second internal gear ring frame 36 by screws 38. The outer circle diameter of the left side of the output sleeve 40 is larger than the outer circle diameter of the right side of the second internal gear ring frame 36, which serves to fix the sixth bearing on the right side.

[0029] The output sleeve 40 and the second internal gear ring frame 36 are connected by screws 38 as one of the output ends.

[0030] The working process of the speed reducer is as follows:

[0031] During input, the input planet carrier 9 and the input sleeve 8 are respectively connected to the motor, and their input rotation directions are opposite. The input sleeve 8 drives the first internal gear ring 19 connected to the first internal gear ring frame 13, and the input planet carrier 9 drives four first planet gears 20 through the connecting shaft 22. Therefore, the rotation direction of the first internal gear ring 19 is opposite to the rotation direction of the revolution of the first planet gears 20. They and the central gear shaft 45 form the planetary system of the first planetary gear train. The central gear shaft 45 is one of the output ends of the speed reducer, and its rotation direction is the same as that of the input sleeve 8.

[0032] The central gear shaft 45 is a gear shaft. It is not only one of the output ends of the speed reducer, but also drives the central gear 27 of the second planetary gear train to provide input power for the second planetary gear train. There are tooth grooves in the central gear 27. It is sleeved on the gear of the central gear shaft 45 and meshes with it. There are also four planetary gear shafts 25 meshing with the central gear 27. The four planetary gear shafts 225 drive the second planet gears 34 of the third planetary gear train. The second internal gear ring 32 meshes with the second planet gears 34. The second internal gear ring 32 is connected to the second internal gear ring frame 36. The second internal gear ring frame 36 is connected to the output sleeve 40. The output sleeve 40 is one of the output ends of the speed reducer, and its rotation direction is the same as that of the input planet carrier 9.

[0033] The above are only the preferred examples of the present invention and are not used to limit or define the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of protection claimed by the present invention.

Claims

1. A planetary gear reducer with double inputs and double outputs is provided with a housing, and three planetary gear trains are successively arranged in the housing from left to right. It is characterized in that: The first planetary gear train includes an input sleeve (8), a first internal gear ring carrier (13), a first internal gear ring (19), an input planet carrier (9), a first planetary gear (20), a central gear shaft (45) and a connecting shaft (22). The number of the first planetary gears (20) is four. The input sleeve (8) is coaxially connected to the first internal gear ring (19) through the first internal gear ring carrier (13). A plurality of first planetary gears (20) with the same parameters are installed on the input planet carrier (9). A plurality of first planetary gears (20) respectively mesh with the left end of the first internal gear ring (19) and the central gear shaft (45). The right end of the central gear shaft (45) is the output end. The second planetary gear train includes a central gear (27) and a planetary gear shaft (25). The central gear (27) is connected to the output end of the central gear shaft (45). The outer circle of the central gear (27) meshes with a plurality of planetary gear shafts (25) that do not revolve around the sun. The third planetary gear train includes a second planetary gear (34), a second internal gear ring (32), a second internal gear ring carrier (36) and an output sleeve (40). The right end of each planetary gear shaft (25) is connected to a second planetary gear (34). A plurality of second planetary gears (34) mesh with the outer second internal gear ring (32). The second internal gear ring (32) is connected to the output sleeve (40) through the second internal gear ring carrier (36). The output sleeve (40) is coaxially arranged with the central gear shaft (45). The input planet carrier (9) is connected to the first planetary gear (20) through the connecting shaft (22). The right side of the connecting shaft (22) is tangent to the inner hole of the first planetary gear (20), passes through the center of the first planetary gear (20) and then is connected to the first baffle (23) to prevent the axial movement of the first planetary gear (20).

2. The planetary gear reducer with double inputs and double outputs according to claim 1, characterized in that: A first bearing (10) and a fifth sleeve (44) are sleeved on the left end of the central gear shaft (45). A step for axially limiting the first bearing (10) is provided in the input planet carrier (9) corresponding to the left side of the first bearing (10). The right side is limited by the fifth sleeve (44). The outer circle of the first bearing (10) is tangent to the inner hole of the input planet carrier (9). The inner hole of the first bearing (10) is tangent to the outer circle of the left end of the central gear shaft (45).

Images