Harmonic reducer with high torque and large speed ratio

Abstract

The utility model provides a harmonic reducer with high torque and large speed ratio, which comprises an outer shell, an input shaft, an output shaft, a rigid gear, a flexible gear and a conversion shaft, a cam is arranged on the input shaft, and a flexible bearing is arranged on the cam to form a wave generator; the input shaft and the output shaft are rotatably and coaxially arranged through the first bearing and the second bearing respectively, the conversion shaft is arranged between the input shaft and the output shaft, one end of the conversion shaft is fixed to the input shaft, and the other end of the conversion shaft is rotatably installed at the end of the output shaft through the third bearing. The harmonic reducer has the beneficial effects that the conversion shaft is coaxially connected with the input shaft and the output shaft, the input and output coaxiality of the harmonic reducer can be improved, and the axial run-out of the input shaft and the output shaft is reduced, so that the vibration and the noise during the operation of the harmonic reducer are reduced, the stable performance of the harmonic reducer can be kept in the long-time operation process, and the service life of the harmonic reducer is prolonged. The torque bearing capacity can also be improved; the harmonic reducer further has the advantage of being compact in overall structure, and the installation space can be saved.

Description

Technical Field

[0001] The utility model relates to the technical field of power transmission, in particular to a high-torque and high-speed ratio harmonic reducer. Background Art

[0002] The harmonic reducer is mainly composed of three main basic components: wave generator, flexible wheel and rigid wheel. The harmonic reducer is a new transmission structure in the gear reducer. It uses flexible gears to generate controllable elastic deformation waves, causing the teeth of the rigid wheel and the flexible wheel to be staggered relative to each other to transmit power and motion. Harmonic reducers are widely used in aerospace, energy, navigation, shipbuilding, bionic machinery and transportation due to their advantages such as large transmission ratio, strong load-bearing capacity, high transmission accuracy and high transmission efficiency. The use of harmonic reducers in servo systems with particularly high dynamic performance can better demonstrate the superiority of harmonic reducers.

[0003] However, the input and output of traditional harmonic reducers on the market are separate, the input shaft and the output shaft are not coaxial, and there is a gap between the input shaft and the output shaft, which will cause the harmonic reducer to produce greater vibration during movement, and its accuracy cannot be maintained for a long time. Therefore, the market is in urgent need of a harmonic reducer with high stability and high precision to solve these problems of traditional harmonic reducers. Utility Model Content

[0004] In view of this, in order to reduce the large vibration generated during the movement of the harmonic reducer, improve the stability of the operation of the harmonic reducer, and enable it to maintain the transmission accuracy for a long time, the utility model provides a high-torque and high-speed ratio harmonic reducer, including an outer shell, an input shaft, an output shaft, a flexible wheel, a rigid wheel and a conversion shaft;

[0005] The two ends of the outer shell are respectively an input end and an output end. The input end of the outer shell is fixedly provided with a connecting flange. A mounting hole is provided in the middle of the connecting flange. The input shaft is rotatably arranged in the mounting hole of the connecting flange through a first bearing. A cam is sleeved on the input shaft. The rigid wheel is fixed to the end of the outer shell.

[0006] The output shaft is arranged in the input end of the outer shell through two second bearings, the flexible wheel is fixed on the output shaft, and the gear teeth of the outer ring of the flexible wheel are partially meshed with the gear teeth of the rigid wheel;

[0007] A flexible bearing is fixedly sleeved on the cam of the input shaft, and the outer ring of the flexible bearing is interference-connected with the inner wall of the flexible wheel;

[0008] One end of the conversion shaft is fixedly connected to the input shaft, and the other end of the conversion shaft is connected to the output shaft via a third bearing, and the input shaft, the output shaft and the conversion shaft are coaxially arranged.

[0009] Furthermore, the first bearing, the second bearing and the third bearing are all deep groove ball bearings.

[0010] Furthermore, the connecting flange is connected to the input motor.

[0011] Furthermore, a bearing mounting groove is provided at the end of the output shaft close to the input shaft, and the third bearing is installed in the bearing mounting groove.

[0012] Furthermore, a stopper is provided at the input end of the outer shell, the rigid wheel is fixed to the stopper by a first fastening screw, and the rigid wheel is located in the connecting flange.

[0013] Furthermore, an output shaft pressure plate is provided at the end of the output shaft close to the input shaft, and the bearing mounting groove is located on the output shaft pressure plate.

[0014] Furthermore, the output shaft pressure plate is fixed to the end of the output shaft by a second fastening screw.

[0015] Furthermore, a step ring is provided at the end of the output shaft away from the input shaft, two second bearings are located between the step ring and the output shaft pressure plate, and a bearing clamping ring is provided on the outer sleeve of the output shaft, and the bearing clamping ring is located between the two second bearings.

[0016] Furthermore, the number of teeth on the flex spline is 392, and the number of teeth on the rigid spline is 394.

[0017] Furthermore, a breathable cap is provided on the outer shell.

[0018] The beneficial effects of the high torque and high speed ratio harmonic reducer of the utility model are:

[0019] 1. The harmonic reducer includes an outer shell, an input shaft, an output shaft, a rigid wheel, a flexible wheel and a conversion shaft, wherein the input shaft and the output shaft are rotatably coaxially arranged through a first bearing and a second bearing respectively, the conversion shaft is arranged between the input shaft and the output shaft, one end of the conversion shaft is fixed on the input shaft, and the other end is rotatably mounted on the end of the output shaft through a third bearing. In the above structure, the conversion shaft can improve the coaxiality of the input and output of the harmonic reducer, and reduce the axial runout of the input shaft and the output shaft, thereby reducing the vibration and noise during its operation, so that its performance can be kept stable during long-term operation.

[0020] 2. In the above harmonic reducer structure, the input shaft and the output shaft are both installed in the outer shell by deep groove ball bearings, and the output shaft is supported by two bearings. The input shaft and the output shaft are connected by a conversion shaft, so that the torque transmission components can be ensured to be coaxial, so that the harmonic reducer can carry a higher input speed and transmit a larger torque.

[0021] 3. The input shaft, rigid wheel and flexible wheel of the harmonic reducer are all located in the outer shell. The input shaft supports the flexible wheel through a flexible bearing so that the flexible wheel teeth are meshed with the rigid wheel teeth. This makes the overall structure of the harmonic reducer more compact and saves installation space. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional view of a high-torque and high-speed ratio harmonic reducer according to an embodiment of the utility model.

[0023] In the above figure: 1-outer shell, 11-breathable cap, 2-connecting flange, 3-input shaft, 31-first bearing, 32-cam, 4-output shaft, 41-step ring, 42-second bearing, 43-bearing clamping ring, 5-rigid wheel, 6-flexible wheel, 61-flexible bearing, 7-conversion shaft, 71-third bearing, 8-output shaft pressure plate. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the utility model clearer, the implementation mode of the utility model will be further described below in conjunction with the accompanying drawings.

[0025] Please refer to Figure 1 , Figure 1 It is a cross-sectional view of a high-torque and high-speed ratio harmonic reducer of the utility model. The harmonic reducer comprises an outer shell 1, an input shaft 3, an output shaft 4, a rigid wheel 5, a flexible wheel 6, and a conversion shaft 7.

[0026] The two ends of the outer shell 1 are respectively an input end and an output end. The input end of the outer shell 1 is fixedly provided with a connecting flange 2. In this embodiment, the connecting flange 2 is used to be connected to the rotating shaft of the input motor, so that the harmonic reducer can be directly connected to the input motor.

[0027] A mounting hole is provided in the middle of the connecting flange 2 , and the input shaft 3 is rotatably arranged in the mounting hole of the connecting flange through a first bearing 31 , and the rigid wheel 5 is fixed to the end of the outer shell 1 .

[0028] The output shaft 4 is arranged in the input end of the outer shell 1 through two second bearings 42, and one end of the output shaft 4 extends out of the output end of the outer shell. The flexible wheel 6 is fixedly connected to the output shaft 4, so that the two rotate synchronously. The outer ring of the flexible wheel 4 is provided with gear teeth, and the inner ring of the rigid wheel 5 is provided with gear teeth. The number of gear teeth of the two is different, wherein the number of gear teeth of the outer ring of the flexible wheel 4 is less than the number of gear teeth of the inner ring of the rigid wheel 5, and the outer ring gear teeth of the flexible wheel 4 are partially meshed with the inner ring gear teeth of the rigid wheel 5.

[0029] The input shaft 3 is fixedly provided with a cam 32 with an elliptical cross-section, and the cam 32 on the input shaft 3 is fixedly sleeved with a flexible bearing 61. The cam 32 and the flexible bearing 61 arranged thereon together constitute a wave generator. The flexible bearing 61 and the flexible wheel 6 are both elastic. The inner ring of the flexible bearing 61 is fixed on the cam 32 of the input shaft, and the outer ring of the flexible bearing 61 is interference connected with the inner wall of the flexible wheel 6. One end of the conversion shaft 7 is fixedly connected to the end of the input shaft 3, and the other end of the conversion shaft 7 is connected to the output shaft 4 through a third bearing 71, and the input shaft, the output shaft 4 and the conversion shaft 7 are coaxially arranged.

[0030] In the above structure, the conversion shaft 7 rotates to connect the input shaft and the output shaft 4 so that the two remain coaxial, and the two ends of the conversion shaft 7 provide axial thrust for the input shaft and the output shaft 4 respectively, which can reduce the axial runout of the input shaft and the output shaft, thereby reducing the vibration and noise during operation, so that its performance can be maintained stable during long-term operation.

[0031] Preferably, the first bearing 31, the second bearing 42 and the third bearing 71 are all deep groove ball bearings. The end of the output shaft 4 close to the input shaft is provided with a bearing mounting groove, and the third bearing 71 is installed in the bearing mounting groove. The deep groove ball bearing can rotatably support the input shaft, the output shaft 4 and the conversion shaft 7, so that they rotate smoothly, thereby improving the stability of the operation of the harmonic reducer.

[0032] Preferably, a stopper is provided at the input end of the outer shell 1, and the rigid wheel 5 is fixed to the stopper by a first fastening screw. The rigid wheel 5 is located in the connecting flange 2, and the stopper structure at the input end of the outer shell 1 can accurately position the rigid wheel 5.

[0033] Preferably, an output shaft pressure plate 8 is provided at the end of the output shaft 4 close to the input shaft, and the bearing mounting groove is located on the output shaft pressure plate 8. The output shaft pressure plate 8 is fixed to the end of the input shaft 3 by a second fastening screw. A step ring 41 is provided at the end of the output shaft 4 away from the input shaft, and two second bearings 42 are located between the step ring 41 and the output shaft pressure plate 8. A bearing clamp ring 43 is provided on the outer sleeve of the output shaft, and the bearing clamp ring 43 is located between the two second bearings 42. In this way, the two second bearings 42 can be used to axially position the output shaft 4, thereby further reducing the axial runout of the output shaft 4 during operation. In this embodiment, the first fastening screw and the second fastening screw are both hexagon socket screws. The second fastening screw connects the output shaft pressure plate 8, the flexible wheel 6 and the output shaft 4 into a whole.

[0034] Preferably, one of the two second bearings 42 close to the output end of the outer shell 1 is further provided with an O-ring, and the O-ring is located between the outer ring of the second bearing 42 and the inner wall of the outer shell 1 to seal the output end of the outer shell 1; a breathable cap is provided on the outer shell 1.

[0035] Preferably, the number of teeth on the outer ring of the flexible wheel 6 in this embodiment is 392, and the number of teeth on the inner ring of the rigid wheel is 394. The single-stage reduction ratio of the harmonic reducer can reach 196, realizing a high-speed ratio transmission.

[0036] In this document, the directional words such as front, back, top, and bottom are defined by the positions of the components in the drawings and the positions of the components relative to each other, and are only for the sake of clarity and convenience in expressing the technical solution. It should be understood that the use of the directional words should not limit the scope of protection claimed in this application.

[0037] In the absence of conflict, the above embodiments and features in the embodiments may be combined with each other.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high torque and high speed ratio harmonic reducer, characterized in that: It includes an outer shell, an input shaft, an output shaft, a flexible wheel, a rigid wheel and a conversion shaft; The two ends of the outer shell are respectively an input end and an output end. The input end of the outer shell is fixedly provided with a connecting flange. A mounting hole is provided in the middle of the connecting flange. The input shaft is rotatably arranged in the mounting hole of the connecting flange through a first bearing. A cam is sleeved on the input shaft. The rigid wheel is fixed to the end of the outer shell. The output shaft is arranged in the input end of the outer shell through two second bearings, the flexible wheel is fixed on the output shaft, and the gear teeth of the outer ring of the flexible wheel are partially meshed with the gear teeth of the inner ring of the rigid wheel; A flexible bearing is fixedly sleeved on the cam of the input shaft, and the outer ring of the flexible bearing is interference-connected with the inner wall of the flexible wheel; One end of the conversion shaft is fixedly connected to the input shaft, and the other end of the conversion shaft is connected to the output shaft via a third bearing, and the input shaft, the output shaft and the conversion shaft are coaxially arranged.

2. A high torque and high speed ratio harmonic reducer according to claim 1, characterized in that: The first bearing, the second bearing and the third bearing are all deep groove ball bearings.

3. The high torque and high speed ratio harmonic reducer according to claim 1, characterized in that: The connecting flange is connected to the input motor.

4. The high torque and high speed ratio harmonic reducer according to claim 1, characterized in that: A bearing installation groove is provided at the end of the output shaft close to the input shaft, and the third bearing is installed in the bearing installation groove.

5. The high torque and high speed ratio harmonic reducer according to claim 4, characterized in that: A stopper is provided at the input end of the outer shell, and the rigid wheel is fixed to the stopper by a first fastening screw, and the rigid wheel is located in the connecting flange.

6. The high torque and high speed ratio harmonic reducer according to claim 5, characterized in that: An output shaft pressure plate is provided at the end of the output shaft close to the input shaft, and the bearing mounting groove is located on the output shaft pressure plate.

7. The high torque and high speed ratio harmonic reducer according to claim 6, characterized in that: The output shaft pressure plate is fixed to the end of the output shaft by a second fastening screw.

8. The high torque and high speed ratio harmonic reducer according to claim 6, characterized in that: The end of the output shaft away from the input shaft is provided with a step ring, two second bearings are located between the step ring and the output shaft pressure plate, and the output shaft outer sleeve is provided with a bearing clamping ring, and the bearing clamping ring is located between the two second bearings.

9. The high torque and high speed ratio harmonic reducer according to claim 1, characterized in that: The number of teeth on the flexible spline is 392, and the number of teeth on the rigid spline is 394.

10. The high torque and high speed ratio harmonic reducer according to claim 1, characterized in that: A breathable cap is arranged on the outer shell.

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