Three-stage speed change device

Abstract

The utility model relates to a three-stage speed change device in the field of speed change equipment, which comprises a front shell and a rear shell, the front shell and the rear shell are connected through a duplex inner gear ring, an input gear shaft and a gear supporting shaft are arranged in the front shell, one end of the gear supporting shaft is in transition fit with an inner hole of the front shell and is provided with a large gear, and the other end of the gear supporting shaft is provided with a gear shaft. The large gear is meshed with an input gear shaft, the input gear shaft is provided with an internal spline, one end of the input gear shaft is a motor input end, the rear shell is provided with an output shaft, the other end of the gear supporting shaft is supported in an inner hole in one end of the output shaft through a first ball bearing, and the gear supporting shaft is provided with a two-stage speed change mechanism and a three-stage speed change mechanism in a matched mode. The speed reducer is compact in structure, small in size, low in cost, capable of achieving multi-stage speed change and suitable for occasions where an input power shaft and an output shaft are not concentric, but the axial size is small, and the requirement for the speed change ratio is large; and power transmission is stable without obvious vibration feeling.

Description

Technical Field

[0001] This utility model belongs to the field of speed change equipment, specifically relating to a three-stage speed change device. Background Technology

[0002] In the field of engineering machinery such as stone cutting, 60-100kW variable frequency motors can reach speeds of 4000-5000rpm, but require output torques of 4800-6000Nm, while the speed can only be around 150rpm. Existing transmission devices are usually parallel shaft gearboxes, which are very large, heavy, and costly to meet the above technical specifications. However, the space for arranging a transmission device on a cutting machine is limited. Existing technologies cannot meet the requirements of gear ratio and power output in a smaller size. Therefore, a three-stage transmission device is needed to solve the above technical problems. Summary of the Invention

[0003] To address the aforementioned deficiencies in the existing technology, this utility model provides a three-stage transmission device, comprising a front housing and a rear housing, which are connected by a double internal gear ring. The front housing contains an input gear shaft and a gear support shaft. One end of the gear support shaft is fitted with the inner hole of the front housing and has a large gear. The large gear meshes with the input gear shaft, which has an internal spline. One end of the input gear shaft is the motor input end. The rear housing contains an output shaft. The other end of the gear support shaft is supported in the inner hole of one end of the output shaft by a ball bearing. A two-stage transmission mechanism and a three-stage transmission mechanism are fitted onto the gear support shaft.

[0004] Preferably, the two-stage transmission mechanism includes a primary sun gear, a primary planetary gear, and a primary planetary carrier. The primary sun gear is mounted on a gear support shaft. The large gear meshes with the primary sun gear via an internal spline. The primary sun gear meshes with the primary planetary gear. The primary planetary gear is located on the primary planetary carrier. The primary planetary carrier is mounted within a double internal gear ring.

[0005] Preferably, the three-stage transmission mechanism includes a second-stage sun gear, a second-stage planetary gear, and a second-stage planetary carrier. The second-stage sun gear is mounted on a gear support shaft and meshes with the second-stage planetary gear. The second-stage planetary gear is mounted on the second-stage planetary carrier via a pin. The second-stage planetary carrier is also located within a double internal gear ring and is connected to the output shaft via an internal spline.

[0006] Preferably, the output shaft is mounted on the rear housing via two back-to-back tapered roller bearings. The output shaft is fitted with a rear end cover, which is sealed to the rear housing by an O-ring. The output shaft is interference-fitted with a spacer, which is face-sealed to the output shaft by an O-ring. A skeleton oil seal is provided between the spacer and the rear end cover.

[0007] Preferably, the other end of the input gear shaft is provided with a plug and a matching O-ring seal.

[0008] Preferably, the inner bore of the large gear is connected to the gear support shaft via a cylindrical roller bearing.

[0009] Preferably, the first-stage sun gear does not directly contact the gear support shaft, and there is a gap between them. The first-stage sun gear is radially floating and the axial direction of the first-stage sun gear is limited by the end face through the gear support shaft and the ball bearing installed inside the second-stage sun gear.

[0010] This utility model also includes other components that enable a three-speed transmission device to function properly, all of which are conventional techniques in the field. Furthermore, devices or components not limited in this utility model, such as double internal gear rings, internal splines, input gear shafts, sun gears, planetary gears, planetary carriers, tapered roller bearings, O-rings, cylindrical roller bearings, and ball bearings, all employ conventional techniques and equipment in the field.

[0011] The advantages of this utility model are: compact structure, small size, low cost, multi-stage speed change, suitable for occasions where the input power shaft and output shaft are not concentric, but the axial dimension is small and the speed ratio requirement is large; the power transmission is smooth and there is no obvious vibration. Attached Figure Description

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic diagram of a three-stage speed change device in an embodiment of this utility model.

[0014] In the diagram: 1. Front housing; 2. Cylindrical roller bearing I; 3. Ball bearing III; 4. Front end cover; 5. Input gear shaft; 6. Plug; 7. O-ring III; 8. Large gear; 9. Gear support shaft; 10. First-stage sun gear; 11. Cylindrical roller bearing II; 12. First-stage planetary gear; 13. First-stage planetary carrier; 14. Roller bearing; 15. Double internal gear ring; 16. Second-stage sun gear; 17. Second-stage planetary gear; 18. Second-stage planetary carrier; 19. Output shaft; 20. Rear housing; 21. Rear end cover; 22. Spacer; 23. Tapered roller bearing; 24. Lock nut; 25. Ball bearing I; 26. Baffle; 27. Ball bearing II; 28. Pin; 29. ​​Needle roller; 30. Double-lip skeleton oil seal; 31. O-ring II; 32. O-ring I; 33. Locking washer. Detailed Implementation

[0015] The present invention will now be clearly described with reference to the accompanying drawings and specific embodiments. This description is merely for explaining the present invention and is not intended to limit it. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the protection scope of the present invention.

[0016] Example

[0017] like Figure 1 As shown, this utility model provides a three-stage transmission device, including a front housing 1 and a rear housing 20. The front housing 1 and the rear housing 20 are connected by a double internal gear ring 15. The front housing 1 is provided with a gear support shaft 9 and an input gear shaft 5 with internal splines. One end of the gear support shaft 9 is transitionally fitted with the inner hole of the front housing 1 and is provided with a large gear 8. The large gear 8 meshes with the input gear shaft 5. One end of the input gear shaft 5 is the motor input end. The input gear shaft 5 has a through hole structure, which facilitates the involute spline broaching machining of its internal splines. The rear housing 20 is provided with an output shaft 19. The other end of the gear support shaft 9 is supported in the inner hole of one end of the output shaft 19 by a ball bearing 25 to ensure the smooth transmission of the large gear 8. A two-stage transmission mechanism and a three-stage transmission mechanism are fitted on the gear support shaft 9.

[0018] It should be noted that the double internal gear ring 15 can be a single set of internal gear parameters with the same number of teeth, module, and pressure angle, or it can be a set of different double internal gear parameters with different numbers of teeth, modules, and pressure angles. When designing gear parameters with different modules, numbers of teeth, and pressure angles, a clearance structure for machining relief grooves should be designed between the two types of internal gears of the double internal gear ring 15 to facilitate the use of gear shaping or gear hobbing (gear hobbing is also called gear turning or gear shaping).

[0019] An external gear input shaft 5 with an internal spline blind hole is mounted on the front housing 1 via a ball bearing 3 and a cylindrical roller bearing 2. The front housing 1 is provided with a front end cover 4. The input shaft 5 is connected to the front end cover 4 via the ball bearing 3. The internal spline of the input shaft 5 solves the problems of low machining efficiency, poor machining accuracy of internal splines, and easy breakage of gear shapers due to poor chip removal. It is designed as a through-hole internal spline, and the internal spline can be solved by broaching, which greatly reduces the machining cost and greatly improves the machining cycle time.

[0020] The two-stage transmission mechanism includes a primary sun gear 10, a primary planetary gear 12, and a primary planetary carrier 13. The primary sun gear 10 is mounted on the gear support shaft 9. The large gear 8 meshes with the primary sun gear 10 through an internal spline. The primary sun gear 10 meshes with the primary planetary gear 12. The primary planetary gear 12 is mounted on the primary planetary carrier 13 through roller bearings 14. The primary planetary carrier 13 is located inside a double internal gear ring 15.

[0021] The three-stage transmission mechanism includes a second-stage sun gear 16, a second-stage planetary gear 17, and a second-stage planetary carrier 18. The second-stage sun gear 16 is mounted on the gear support shaft 9. The first-stage planetary carrier 13 is connected to the second-stage sun gear 16 via an internal spline, outputting power and speed. The second-stage sun gear 16 meshes with the second-stage planetary gear 17. The second-stage planetary gear 17 is mounted on the second-stage planetary carrier 18 via a pin 28. The pin 28 is fitted with a needle roller 29. The second-stage planetary carrier 18 is also located within the double internal gear ring 15 and is connected to the output shaft 19 via an internal spline.

[0022] The output shaft 19 is mounted on the rear housing 20 via two back-to-back tapered roller bearings 23. The output shaft 19 is fitted with a rear end cover 21, which is sealed to the rear housing 20 by an O-ring 32. The output shaft 19 is also interference-fitted with a spacer 22, which is sealed to the output shaft 19 at the end face by another O-ring 31. A skeleton oil seal is provided between the spacer 22 and the rear end cover 21. The skeleton oil seal is a double-lip skeleton oil seal 30, which serves to simultaneously facilitate oil seal replacement and ensure the machinability of the keyway mounting area of ​​the output shaft 19.

[0023] The other end of the input gear shaft 5 is provided with a plug 6 and a mating O-ring 3. The plug 6 and the inner hole of the input gear shaft 5 are in transition fit, so that the outer circle of the O-ring 3 is not cut off during assembly. Two O-rings 3 7 can be designed to prevent the internal gear lubricating oil of the transmission device from leaking from the inner hole of the input gear shaft 5 to the outside of the front housing 1. In order to stop the lubricating oil leakage problem, a plug 6 with double O-rings is designed and press-fitted into the inner hole of the input gear shaft 5. The plug 6 is axially positioned in the inner hole of the input gear shaft 5 by a step.

[0024] The inner hole of the large gear 8 is connected to the gear support shaft 9 through a cylindrical roller bearing 11.

[0025] The first-stage sun gear 10 does not directly contact the gear support shaft 9, and there is a gap between them. The first-stage sun gear 10 is radially floating and does not need to be fixed. The first-stage sun gear 10 is axially restricted by the end face through the gear support shaft 9 and the ball bearing 27 installed inside the second-stage sun gear 16, which only retains the rotational clearance and cannot move axially over a large range.

[0026] In this embodiment, a cylindrical roller bearing is installed in the inner hole of the large gear 8 that meshes with the input gear shaft 5. The cylindrical roller bearing is installed on the gear support shaft 9. The large gear 8 meshes with the first-stage sun gear 10 through the internal spline. This part of the external teeth is equivalent to the function of the external spline.

[0027] The gear support shaft 9 is located near the large gear 8 and is mounted on the front housing 1 via an transition fit. A sealing ring is installed on its outer circumference, and it is tightened by an internal thread and axially fixed to the front housing 1. The distal end of the gear support shaft 9 passes through the inner holes of the first-stage sun gear 10 and the second-stage sun gear 16 in sequence, and is then radially mounted in the inner hole of the output shaft 19 via a ball bearing 25. A baffle 26 is provided between the ball bearing 25 and the ball bearing 27 at one end of the gear support shaft 9. The above arrangement avoids the vibration and noise problems of gear transmission caused by the cantilever structure of the gear support shaft 9.

[0028] The two-stage and three-stage transmission structures of this utility model are both planetary gear structures. The double internal gear ring 15 is connected and fixed to the front and rear housings 20, and both output power through the planetary carrier. A ball bearing 27 is installed at each end of the second-stage sun gear 16 to provide axial positioning and prevent end face wear caused by different rotational speeds at the two ends.

[0029] The output shaft 19 structure of this utility model is designed with two tapered roller bearings 23 back to back, and the axial tension is a structure with a locking nut 24 installed at the inner end, and the locking nut 24 is fitted with a stop washer 33.

[0030] The three-stage transmission device of this utility model has a parallel shaft external gear transmission for the first stage, and planetary reduction structure for the second and third stages. Its weight is only one-third of that of the parallel shaft transmission device, and the product cost can be reduced by about 30%.

[0031] Example 2

[0032] The difference between this embodiment and Embodiment 1 is that the output shaft structure is designed as two cylindrical roller bearings facing each other, and the axial tension is achieved by a locking nut installed at the outer end.

[0033] The embodiments of this utility model have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A three-stage transmission device, comprising a front housing and a rear housing, characterized in that: The front housing and the rear housing are connected by a double internal gear ring. The front housing is provided with an input gear shaft and a gear support shaft. One end of the gear support shaft is transitionally fitted with the inner hole of the front housing and is provided with a large gear. The large gear meshes with the input gear shaft. The input gear shaft is provided with an internal spline. One end of the input gear shaft is the motor input end. The rear housing is provided with an output shaft. The other end of the gear support shaft is supported in the inner hole of one end of the output shaft by a ball bearing. The gear support shaft is fitted with a two-stage speed change mechanism and a three-stage speed change mechanism.

2. The three-stage transmission device according to claim 1, characterized in that: The two-stage transmission mechanism includes a primary sun gear, a primary planetary gear, and a primary planetary carrier. The primary sun gear is mounted on a gear support shaft. The large gear meshes with the primary sun gear via an internal spline. The primary sun gear meshes with the primary planetary gear. The primary planetary gear is located on the primary planetary carrier, which is mounted within a double internal gear ring.

3. A three-stage speed change device according to claim 2, characterized in that: The three-stage transmission mechanism includes a second-stage sun gear, a second-stage planetary gear, and a second-stage planetary carrier. The second-stage sun gear is mounted on a gear support shaft and meshes with the second-stage planetary gear. The second-stage planetary gear is mounted on the second-stage planetary carrier via a pin. The second-stage planetary carrier is also located within a double internal gear ring and is connected to the output shaft via an internal spline.

4. A three-stage speed change device according to claim 1, characterized in that: The output shaft is mounted on the rear housing via two back-to-back tapered roller bearings. The output shaft is fitted with a rear end cover, which is sealed to the rear housing by an O-ring. The output shaft is interference-fitted with a spacer, which is sealed to the output shaft end face by an O-ring. A skeleton oil seal is provided between the spacer and the rear end cover.

5. A three-stage speed change device according to claim 1, characterized in that: The other end of the input gear shaft is provided with a plug and a matching O-ring seal.

6. A three-stage speed change device according to claim 1, characterized in that: The inner bore of the large gear is connected to the gear support shaft via a cylindrical roller bearing.

7. A three-stage speed change device according to claim 2, characterized in that: The first-stage sun gear does not directly contact the gear support shaft, and there is a gap between them. The first-stage sun gear is radially floating and is axially constrained by the end face of the first-stage sun gear through the gear support shaft and the ball bearing installed inside the second-stage sun gear.

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