Novel large-speed-ratio transmission transmission structure

Abstract

The utility model relates to the technical field of transmissions, in particular to a novel large-speed-ratio transmission transmission structure which comprises a first planet gear, a second planet gear, a third planet gear, an inner gear ring, a first sun gear, a second sun gear, a planet carrier, a shell and a rotating shaft. The rotating shaft is rotationally mounted on the side wall of the shell through a second bearing, and the first sun gear is mounted on the rotating shaft; the revolution speed of the planet carrier is adjusted through the gear ratio of the first sun gear to the first planet gear and the gear ratio of the second sun gear to the second planet gear, and therefore one degree of freedom in motion of the planet system is controlled more flexibly, and in other words, under the condition that the size of a main body input gear and the size of an output gear are not changed, the planet carrier can be adjusted. A great transmission speed ratio can be obtained within a reasonable tooth number range allowed by manufacturing only by adjusting the tooth numbers of the first sun gear, the second sun gear, the first planet gear and the second planet gear.

Description

Technical Field

[0001] The utility model relates to the technical field of transmissions, and more specifically, to a novel transmission structure of a large speed ratio transmission. Background Art

[0002] A planetary gear train mainly includes a sun gear, planetary gears, a planet carrier, and an internal gear ring. Among them, the axes of the sun gear, the planet carrier, and the internal gear ring are fixed. The core of the planetary gear is fixed to the planet carrier through a planetary pin, so that in addition to rotating around its own axis, the axis of the planetary gear can also follow the planet carrier and rotate around the axes of other gears.

[0003] Currently, the most common method is to input the transmission torque through the sun gear, fix the internal gear ring to restrict its rotation, and output the transmission torque through the planet carrier. The above process can achieve the purpose of reducing the speed and increasing the torque within a certain range. However, due to the spatial limitations of tool cutting during gear manufacturing, the number of teeth of the sun gear and the planetary gears cannot be too small, and the number of teeth of the internal gear ring cannot be too large. Based on the characteristics and principles of planetary gear train transmission, the speed ratio of the planetary gear train with the internal gear ring fixed is equal to the ratio of the number of teeth of the internal gear ring to the number of teeth of the sun gear plus 1.

[0004] In the prior art, the transmission speed ratio under the conditions of engineering manufacturing capabilities can usually only reach about 2.5 to 7. This speed ratio exceeds the transmission speed ratio of general parallel-axis gears. However, in some special application scenarios, such as rotary tables, robot joints, machine tools, cranes, steam turbines, agricultural machinery, etc., higher transmission speed ratios are required for the reducers, and the reducers in the prior art cannot achieve higher transmission speed ratio requirements. Summary of the Utility Model

[0005] The technical problem to be solved by the utility model is that the transmission speed ratio of the existing transmission planetary gear set can usually only reach about 2.5 to 7, and higher transmission speed ratio requirements cannot be achieved.

[0006] To solve the above problems, the utility model proposes the following technical solutions:

[0007] A novel transmission structure with a large speed ratio includes a first planet gear, a second planet gear, a third planet gear, an internal gear ring, a first sun gear, a second sun gear, a planet carrier, a housing, and a rotating shaft. The internal gear ring is rotatably mounted in the housing through a first bearing. The side wall of the housing is rotatably mounted with the rotating shaft through a second bearing, and the first sun gear is mounted on the rotating shaft. The planet carrier is rotatably connected to the inner wall of the housing through a third bearing and is located between the internal gear ring and the second sun gear. The planet carrier, the internal gear ring, and the second sun gear are coaxially arranged. The second sun gear is fixed inside the housing. The first planet gear, the second planet gear, and the third planet gear are all rotatably mounted on the planet carrier. The first planet gear is used to mesh with the first sun gear, the second planet gear is used to mesh with the second sun gear, and the second planet gear is coaxially arranged with the first planet gear. The two sides of the third planet gear are respectively meshed with the internal gear ring and the second planet gear.

[0008] The novel transmission structure with a large speed ratio provided by the present utility model has the following beneficial effects compared with the prior art, but is not limited to:

[0009] The rotating shaft is driven through a driving mechanism. The rotating shaft drives the first sun gear to rotate, and the first sun gear drives the first planet gear, so that the second planet gear rotates. Since the planet carrier is rotatably connected to the inner wall of the housing through a third bearing and the second sun gear is fixedly arranged, and the second planet gear meshes with the second sun gear, the planet carrier, the first planet gear, and the second planet gear are enabled to rotate integrally around the axis of the planet carrier. Since the two sides of the third planet gear are respectively meshed with the internal gear ring and the second planet gear, the third planet gear rotates around its own rotating shaft and simultaneously rotates around the axis of the planet carrier. The third planet gear plays a transmission role and drives the internal gear ring to rotate, and the power output is realized by driving the internal gear ring to rotate. Among them, the turnover speed of the planet carrier is adjusted through the tooth number ratio of the first sun gear and the first planet gear, and the second sun gear and the second planet gear, so as to more flexibly control one degree of freedom in the movement of the planetary system. That is to say, without changing the sizes of the main input and output gears, only by adjusting the tooth numbers of the first sun gear, the second sun gear, the first planet gear, and the second planet gear, a large transmission speed ratio can be obtained within the reasonable tooth number range allowed by manufacturing to meet the requirements of multi-high transmission speed ratio usage scenarios. The overall structure is very compact and has a larger power density than traditional transmissions.

[0010] Preferably, the planet carrier includes a first ring frame, and the first ring frame is rotatably mounted in the housing through the third bearing. A plurality of first pin shafts are evenly spaced and mounted on the first ring frame, and the first planet gear and the second planet gear are both rotatably mounted on the first pin shafts.

[0011] Preferably, the planet carrier further includes a second ring frame coaxially arranged with the first ring frame, and the second ring frame is fixedly installed at one end of the first pin shaft away from the first ring frame.

[0012] Preferably, the planet carrier further includes a third ring frame coaxially arranged with the first ring frame. A plurality of second pin shafts are evenly spaced and installed on the third ring frame, and the third planet gear is rotatably installed on the second pin shafts.

[0013] Preferably, the planet carrier further includes a fourth ring frame coaxially arranged with the third ring frame. The fourth ring frame has the same size as the third ring frame, and the fourth ring frame is fixedly installed at one end of the second pin shaft away from the third ring frame.

[0014] Preferably, there are a plurality of the first planet gears. Correspondingly, there are also a plurality of the second planet gears and the third planet gears. The first sun gear is located between the plurality of first planet gears and meshes with the plurality of first planet gears.

[0015] Preferably, the transmission structure of the new high reduction ratio transmission further includes a fixed cylinder fixed inside the housing and facing the rotating shaft, and the second sun gear is fixed on the fixed cylinder.

[0016] Preferably, the side wall of the fixed cylinder facing the rotating shaft is provided with a through hole, and the rotating shaft passes through the through hole and is rotatably connected to the through hole through a fourth bearing.

[0017] Preferably, the rotating shaft is used to be driven by a driving mechanism; the internal gear ring is used to be connected to a turntable to output power. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the overall structure of the transmission structure of the new high reduction ratio transmission according to an embodiment of the present invention;

[0019] Figure 2 is a schematic sectional view of the transmission structure of the new high reduction ratio transmission according to an embodiment of the present invention.

[0020] DESCRIPTION OF THE REFERENCE NUMERALS:

[0021] 1 first planet gear, 10 fixed cylinder, 2 second planet gear, 3 third planet gear, 4 internal gear ring, 5 first sun gear, 6 second sun gear, 7 planet carrier, 71 first ring frame, 72 second ring frame, 73 third ring frame, 74 fourth ring frame, 75 first pin shaft, 76 second pin shaft, 8 housing, 9 rotating shaft. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The following further describes the embodiments of the present application in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present application, but cannot be used to limit the scope of the present application.

[0023] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model 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, and therefore should not be construed as a limitation to the present utility model.

[0024] It should be noted that in the coordinate system XYZ provided herein, the positive direction of the X-axis represents the right side, the reverse direction of the X-axis represents the left side, the positive direction of the Y-axis represents the front, the reverse direction of the Y-axis represents the rear, the positive direction of the Z-axis represents the upper side, and the reverse direction of the Z-axis represents the lower side; the meanings represented by the Z-axis, X-axis, and Y-axis are only for the convenience of describing the present utility model 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, and therefore should not be construed as a limitation to the present utility model.

[0025] Referring to Figure 1 - Figure 2 , a novel transmission structure of a large speed ratio provided by the present utility model includes a first planetary gear 1, a second planetary gear 2, a third planetary gear 3, an internal gear ring 4, a first sun gear 5, a second sun gear 6, a planetary carrier 7, a housing 8, and a rotating shaft 9. The internal gear ring 4 is rotatably mounted in the housing 8 through a first bearing. The side wall of the housing 8 is rotatably mounted with the rotating shaft 9 through a second bearing, and the first sun gear 5 is mounted on the rotating shaft 9. The planetary carrier 7 is rotatably connected to the inner wall of the housing 8 through a third bearing and is located between the internal gear ring 4 and the second sun gear 6. The planetary carrier 7, the internal gear ring 4, and the second sun gear 6 are coaxially arranged. The second sun gear 6 is fixed inside the housing 8. The first planetary gear 1, the second planetary gear 2, and the third planetary gear 3 are all rotatably mounted on the planetary carrier 7. The first planetary gear 1 is used to mesh with the first sun gear 5, the second planetary gear 2 is used to mesh with the second sun gear 6, and the second planetary gear 2 is coaxially arranged with the first planetary gear 1. Both sides of the third planetary gear 3 are meshed with the internal gear ring 4 and the second planetary gear 2 respectively.

[0026] In this embodiment, the rotating shaft 9 is driven by a driving mechanism. The rotating shaft 9 drives the first sun gear 5 to rotate, and the first sun gear 5 drives the first planet gear 1, so that the second planet gear 2 rotates. Since the planet carrier 7 is rotationally connected to the inner wall of the housing 8 through a third bearing, and the second sun gear 6 is fixedly arranged, and the second planet gear 2 meshes with the second sun gear 6, the planet carrier 7, the first planet gear 1 and the second planet gear 2 are enabled to rotate integrally around the axis of the planet carrier 7. Since both sides of the third planet gear 3 are meshed with the internal gear ring 4 and the second planet gear 2 respectively, the third planet gear 3 rotates around its own rotating shaft and simultaneously rotates around the axis of the planet carrier 7. The third planet gear 3 plays a transmission role and drives the internal gear ring 4 to rotate, and power output is achieved by driving the internal gear ring 4 to rotate. Among them, by the tooth number ratios of the first sun gear 5 and the first planet gear 1, and the second sun gear 6 and the second planet gear 2, the revolving speed of the planet carrier 7 is adjusted, so as to more flexibly control one degree of freedom in the movement of the planetary system. That is to say, without changing the sizes of the main body input and output gears, only by adjusting the tooth numbers of the first sun gear 5, the second sun gear 6, the first planet gear 1 and the second planet gear 2, a very large transmission ratio can be obtained within the reasonable tooth number range allowed by manufacturing, so as to meet the requirements of high transmission ratio usage scenarios. The overall structure is very compact, has a larger power density compared with traditional speed changers, and the overall structure is symmetrical. Without using helical gears, the radial force and axial force are basically cancelled each other, and the load on the bearings is relatively low.

[0027] Specifically, based on the motion principle of the planetary system, the ratio of the input speed of the first sun gear 5 to the output speed of the internal gear ring 4 can be calculated as:

[0028]

[0029] Where:

[0030] n is the rotational speed. Then, n4 is the rotational speed of the internal gear ring 4, and n5 is the rotational speed of the first sun gear 5;

[0031] Z is the tooth number of the gear. Then, Z1 is the tooth number of the first planet gear 1, Z2 is the tooth number of the second planet gear 2, Z4 is the tooth number of the internal gear ring 4, Z5 is the tooth number of the first sun gear 5, and Z6 is the tooth number of the second sun gear 6;

[0032] Based on the above calculation principle of the transmission ratio of this patent, only by adjusting the first sun gear 5, the second sun gear 6, the first planet gear 1 and the second planet gear 2, a very large transmission ratio can be obtained within the reasonable tooth number range allowed by manufacturing.

[0033] Refer to Figure 1 , preferably, the planet carrier 7 includes a first ring carrier 71 which is rotatably mounted in the housing 8 through the third bearing; a plurality of first pin shafts 75 are evenly spaced and mounted on the first ring carrier 71, and both the first planet gear 1 and the second planet gear 2 are rotatably mounted on the first pin shafts 75 through bearings.

[0034] Specifically, the diameter of the first ring carrier 71 is larger than the diameter of the second sun gear 6, so as to facilitate mounting the second planet gear 2 on the first pin shafts 75 on the first ring carrier 71 and enabling the second planet gear 2 to mesh with the second sun gear 6.

[0035] Wherein, the first ring carrier 71 is arranged at the front end of the second sun gear 6, the second planet gear 2 is arranged at the front end of the first planet gear 1, and the positions of the second planet gear 2 and the second sun gear 6 are flush, so as to facilitate the second planet gear 2 to mesh with the second sun gear 6.

[0036] In this embodiment, the first ring carrier 71 is provided for mounting the first pin shafts 75, so as to rotatably mount the first planet gear 1 and the second planet gear 2.

[0037] Refer to Figure 1 , preferably, the planet carrier 7 further includes a second ring carrier 72 coaxially arranged with the first ring carrier 71, and the second ring carrier 72 is fixedly mounted on one end of the first pin shafts 75 far from the first ring carrier 71.

[0038] Specifically, the second ring carrier 72 is arranged at the rear end of the first planet gear 1, that is, the first planet gear 1 and the second planet gear 2 are located between the first ring carrier 71 and the second ring carrier 72.

[0039] In this embodiment, the arrangements of the first ring carrier 71 and the second ring carrier 72 are beneficial to defining the revolution trajectories of the first planet gear 1 and the second planet gear 2, so that the first planet gear 1 and the second planet gear 2 can rotate around the axis of the rotating shaft 9.

[0040] Refer to Figure 1 , preferably, the planet carrier 7 further includes a third ring carrier 73 coaxially arranged with the first ring carrier 71, and a plurality of second pin shafts 76 are evenly spaced and mounted on the third ring carrier 73, and the third planet gear 3 is rotatably mounted on the second pin shafts 76.

[0041] Refer to Figure 2, preferably, the planet carrier 7 further includes a fourth ring frame 74 coaxially arranged with the third ring frame 73. The fourth ring frame 74 has the same size as the third ring frame 73, and the fourth ring frame 74 is fixedly installed at one end of the second pin shaft 76 away from the third ring frame 73.

[0042] Specifically, the third ring frame 73 is arranged at the front of the third planet gear 3, the fourth ring frame 74 is located at the rear of the third planet gear 3, and the third planet gear 3 is flush with the position of the first sun gear 5 and the internal gear ring 4, so as to facilitate the meshing of the third planet gear with the first sun gear 5 and the internal gear ring 4.

[0043] In this embodiment, the arrangement of the third ring frame 73 and the fourth ring frame 74 is beneficial to defining the revolution trajectory of the third planet gear 3, so that the third planet gear 3 can rotate along the inner wall of the internal gear ring 4.

[0044] Preferably, a plurality of first planet gears 1 are provided. Correspondingly, a plurality of second planet gears 2 and third planet gears 3 are also provided. The first sun gear 5 is located between the plurality of first planet gears 1 and meshes with the plurality of first planet gears 1.

[0045] Preferably, the rotating shaft 9 is driven by a driving mechanism; the internal gear ring 4 is connected to a turntable to output power.

[0046] In this embodiment, the driving mechanism is used to drive the rotating shaft 9 to rotate. Through the transmission of the first planet gear 1, the second planet gear 2 and the third planet gear 3, the internal gear ring 4 is rotated to output power to the turntable.

[0047] Refer to Figure 1 , preferably, the transmission structure of the new high reduction ratio transmission further includes a fixed cylinder 10 fixed inside the housing 8 and facing the rotating shaft 9. The second sun gear 6 is fixed on the fixed cylinder 10.

[0048] Refer to Figure 2 , preferably, the side wall of the fixed cylinder 10 facing the rotating shaft 9 is provided with a through hole. The rotating shaft 9 passes through the through hole and is rotatably connected to the through hole through a fourth bearing.

[0049] In this embodiment, the fixed cylinder 10 is provided for installing the second sun gear 6, and the fixed connection between the fixed cylinder 10 and the rotating shaft 9 is also beneficial to ensuring the coaxial arrangement of the fixed cylinder 10, the rotating shaft 9, the first sun gear 5 and the second sun gear 6.

[0050] Although the present utility model is disclosed as above, the protection scope of the present utility model is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present utility model, and these changes and modifications will all fall within the protection scope of the present utility model.

Claims

1. A novel transmission structure with a large speed ratio, characterized in that, It includes a first planet gear (1), a second planet gear (2), a third planet gear (3), an internal gear ring (4), a first sun gear (5), a second sun gear (6), a planet carrier (7), a housing (8) and a rotating shaft (9). The internal gear ring (4) is rotatably mounted in the housing (8) through a first bearing. The side wall of the housing (8) is rotatably mounted with the rotating shaft (9) through a second bearing, and the first sun gear (5) is mounted on the rotating shaft (9). The planet carrier (7) is rotatably connected to the inner wall of the housing (8) through a third bearing and is located between the internal gear ring (4) and the second sun gear (6). The planet carrier (7), the internal gear ring (4) and the second sun gear (6) are coaxially arranged. The second sun gear (6) is fixed inside the housing (8). The first planet gear (1), the second planet gear (2) and the third planet gear (3) are all rotatably mounted on the planet carrier (7). The first planet gear (1) is used to mesh with the first sun gear (5), the second planet gear (2) is used to mesh with the second sun gear (6), and the second planet gear (2) is coaxially arranged with the first planet gear (1). The two sides of the third planet gear (3) are respectively meshed with the internal gear ring (4) and the second planet gear (2).

2. The novel transmission structure with a large speed ratio according to claim 1, characterized in that, The planet carrier (7) includes a first ring frame (71), and the first ring frame (71) is rotatably mounted in the housing (8) through the third bearing. A plurality of first pin shafts (75) are evenly spaced and mounted on the first ring frame (71), and the first planet gear (1) and the second planet gear (2) are both rotatably mounted on the first pin shafts (75).

3. The novel transmission structure with a large speed ratio according to claim 2, characterized in that, The planet carrier (7) further includes a second ring frame (72) coaxially arranged with the first ring frame (71), and the second ring frame (72) is fixedly mounted on one end of the first pin shaft (75) away from the first ring frame (71).

4. The novel transmission structure with a large speed ratio according to claim 2, characterized in that The planet carrier (7) further includes a third ring frame (73) coaxially arranged with the first ring frame (71). A plurality of second pin shafts (76) are evenly spaced and mounted on the third ring frame (73), and the third planet gear (3) is rotatably mounted on the second pin shafts (76).

5. The novel large speed ratio transmission structure according to claim 4, characterized in that, The planet carrier (7) further includes a fourth ring frame (74) coaxially arranged with the third ring frame (73), and the fourth ring frame (74) is fixedly mounted on one end of the second pin shaft (76) away from the third ring frame (73).

6. The novel transmission structure with a large speed ratio according to claim 1, characterized in that, There are a plurality of the first planet gears (1). Correspondingly, there are also a plurality of the second planet gears (2) and the third planet gears (3). The first sun gear (5) is located between the plurality of first planet gears (1) and meshes with the plurality of first planet gears (1).

7. The novel transmission structure with a large speed ratio according to claim 1, characterized in that, It further includes a fixed cylinder (10) fixed inside the housing (8) and facing the rotating shaft (9), and the second sun gear (6) is fixed on the fixed cylinder (10).

8. The novel transmission structure with a large speed ratio according to claim 7, characterized in that, The side wall of the fixed cylinder (10) facing the rotating shaft (9) is provided with a through hole, and the rotating shaft (9) passes through the through hole and is rotatably connected to the through hole through a fourth bearing.

9. The novel transmission structure with a large speed ratio according to claim 1, characterized in that, The rotating shaft (9) is used to be driven by a driving mechanism; the internal gear ring (4) is used to be connected to a turntable to output power.

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