A RV reducer

Abstract

The present invention relates to the technical field of reducers, and in particular to an RV reducer, which comprises: two crankshafts, two cycloid wheels, a pinion disk, an end cover, a driving mechanism, and a gear shaft. The two crankshafts are driven to rotate by the driving mechanism, thereby driving the two cycloid wheels to swing, and the cycloid wheels mesh with the pinions on the inner circumference of the pinion disk, thereby driving the pinion disk to rotate. When the driving mechanism drives the two crankshafts to rotate, the planetary wheels installed on the two crankshafts are simultaneously driven to rotate, thereby driving the gear shaft meshing with the planetary wheels to rotate. Since the planetary wheels located on the periphery of the gear shaft are driving wheels, the gear shaft located in the middle is subjected to pressure from the planetary wheels when rotating, so that the planetary wheels and the gear shaft are meshed very tightly, thereby reducing the return clearance of the RV reducer, improving the transmission accuracy of the RV reducer, and making the RV reducer suitable for high-precision machining.

Description

Technical Field

[0001] The invention relates to the field of reducers, in particular to an RV reducer. Background Art

[0002] RV transmission is a newly emerging transmission, which is developed on the basis of traditional pin-cycloid planetary transmission. It not only overcomes the shortcomings of general pin-cycloid transmission, but also has a series of advantages such as small size, light weight, large transmission ratio range, long life, stable accuracy, high efficiency and smooth transmission.

[0003] The existing RV reducer includes a centrally located input gear shaft, which is used to drive at least two planetary gears. The two planetary gears are respectively mounted on two crankshafts. Two eccentric sections are provided in the middle of the crankshaft, and a cycloid wheel is mounted on each eccentric section. Thus, the sun wheel can drive the two cycloid wheels to rotate.

[0004] However, when the input gear shaft of the existing RV reducer rotates, the meshing between it and the planetary gear is too loose, which results in a large return clearance of the RV reducer and low transmission accuracy. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an RV reducer, aiming to solve the problem in the prior art that the meshing between the driving gear and the driven gear is too loose, thereby resulting in a large return clearance and low transmission accuracy of the RV reducer.

[0006] The RV reducer provided by the present invention includes: at least two crankshafts, which are provided with a first eccentric section and a second eccentric section; at least two cycloidal wheels, one of which is installed on the first eccentric section of the two crankshafts, and the other is installed on the second eccentric section of the two crankshafts; a pinion gear disk, whose inner circumference is provided with a plurality of pinions meshing with the two cycloidal wheels; a driving mechanism, which is connected to one end of the two crankshafts and is used to drive the two crankshafts to rotate; at least two planetary wheels, which are respectively installed on the other ends of the two crankshafts; a gear shaft, which is rotatably penetrated by the two pinion gear disks, and the planetary wheels are evenly distributed on a circle with the center of the gear shaft as the center, and the gear shaft is meshed with the two planetary wheels and is driven by the two planetary wheels.

[0007] Furthermore, the needle teeth and the needle tooth disc are integrally formed.

[0008] Furthermore, it also includes: an end cover, a front box body and a rear box body, the end cover is used to provide support force for the needle toothed disk, the front box body and the rear box body are respectively located at the two ends of the cycloidal wheel, the front box body is connected to the rear box body, the rear box body is connected to the end cover, and the crank shaft and the gear shaft can be rotatably installed on the front box body and the rear box body.

[0009] Furthermore, the driving mechanism is mounted on the rear box body and is located at an end of the rear box body away from the cycloid wheel.

[0010] Furthermore, it also includes a limiting assembly, which is arranged on the crank shaft and abuts against the planetary gear to limit the movement of the planetary gear along the axis direction of the crank shaft.

[0011] Furthermore, the limiting assembly includes: a sleeve, which is sleeved on the crank shaft, the sleeve abuts against the planetary gear and is located at an end of the planetary gear close to the driving mechanism; a retaining ring, which is sleeved on the crank shaft, the retaining ring abuts against the planetary gear and is located at an end of the planetary gear away from the sleeve.

[0012] Furthermore, the driving mechanism includes two first driving members, which are respectively used to drive the two crank shafts to rotate.

[0013] Furthermore, the driving mechanism includes a second driving member and a transmission assembly, the second driving member is connected to the transmission assembly, the transmission assembly is connected to one end of the two crank shafts, and the second driving member drives the transmission assembly to drive the two crank shafts to rotate.

[0014] Furthermore, it also includes: a third crankshaft, the middle part of which is also provided with the first eccentric segment and the second eccentric segment, the driving mechanism is connected to one end of the third crankshaft and is used to drive the third crankshaft to rotate; the third planetary gear is installed on the other end of the third crankshaft, and the gear shaft is meshed with the third planetary gear and is driven thereby.

[0015] Furthermore, it also includes a third cycloidal wheel, and a third eccentric segment is also provided on the two crank shafts, and the center line of the third eccentric segment is not colinear with the center lines of the first eccentric segment and the second eccentric segment, and the third cycloidal wheel is installed on the third eccentric segment of the two crank shafts.

[0016] The beneficial effects of the present invention are as follows: the two crank shafts are driven to rotate by the driving mechanism, thereby driving the two cycloid wheels to swing, and the cycloid wheels mesh with the pin teeth on the inner circumference of the pinion disk, thereby driving the pinion disk to rotate. When the driving mechanism drives the two crank shafts to rotate, it will simultaneously drive the planetary wheels installed on the two crank shafts to rotate, thereby driving the gear shaft meshing with the planetary wheels to rotate. Since the planetary wheels located on the periphery of the gear shaft are driving wheels, the gear shaft located in the middle will be subjected to pressure from the planetary wheels when it rotates, so that the planetary wheels press the gear shaft, and the meshing of the two is very tight, thereby reducing the return clearance of the RV reducer, improving the transmission accuracy of the RV reducer, and making the RV reducer suitable for high-precision machining. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0018] Figure 1 It is a partial structural half-section view of the present invention;

[0019] Figure 2 It is a partial structural schematic diagram of the present invention;

[0020] Figure 3 It is a partial structural exploded view of the present invention;

[0021] Figure 4 It is a quarter cross-sectional view of a part of the structure of the present invention;

[0022] Figure 5 is another half cross-sectional view of a partial structure of the present invention;

[0023] Figure 6 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 7 It is a schematic diagram of the overall structure of the present invention from another angle;

[0025] The reference numerals in the figures are:

[0026] 1. crankshaft; 101. first eccentric section; 102. second eccentric section; 2. cycloid wheel; 3. pinion gear; 301. pinion; 302. first annular extension section; 4. driving mechanism; 401. first driving member; 5. planetary gear; 6. gear shaft; 7. end cover; 8. front housing; 9. rear housing; 901. second annular extension section; 10. first bearing; 11. second bearing; 12. screw; 13. nut column; 14. limit assembly; 1401. sleeve; 1402. retaining ring; 15. output disc; 16. third bearing; 17. fourth bearing; 18. spacer. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, the preferred embodiments of the present invention are described in detail.

[0028] The present invention provides an RV reducer, such as Figure 1As shown, the RV reducer includes: at least two crankshafts 1, at least two cycloid wheels 2, two pinion gears 3, a driving mechanism 4, at least two planetary wheels 5 and a gear shaft 6. The two crankshafts 1 are provided with a first eccentric section 101 and a second eccentric section 102. One cycloid wheel 2 is mounted on the first eccentric section 101 of the two crankshafts 1, and the other cycloid wheel 2 is mounted on the second eccentric section 102 of the two crankshafts 1. The inner circumference of the pinion gear 3 is provided with a plurality of pinions 301 meshing with the two cycloid wheels 2. The driving mechanism 4 is connected to one end of the two crankshafts 1 and is used to drive the two crankshafts 1 to rotate. The two planetary wheels 5 are respectively mounted on the other ends of the two crankshafts 1. The gear shaft 6 is rotatably penetrated through the two pinion gears 3, and the planetary wheels 5 are evenly distributed on a circle with the center of the gear shaft 6 as the center. The gear shaft 6 meshes with the two planetary wheels 5 and is driven by the two planetary wheels 5.

[0029] By implementing this embodiment, the driving mechanism 4 drives the two crankshafts 1 to rotate, thereby driving the two cycloid wheels 2 to swing, and the cycloid wheels 2 mesh with the pinions 31 on the inner circumference of the pinion gear 3, thereby driving the pinion gear 3 to rotate. When the driving mechanism 4 drives the two crankshafts 1 to rotate, it will simultaneously drive the planetary wheels 5 installed on the two crankshafts 1 to rotate, thereby driving the gear shaft 6 meshing with the planetary wheels 5 to rotate. Since the planetary wheels 5 located around the gear shaft 6 are driving wheels, the gear shaft 6 located in the middle will be subjected to pressure from the planetary wheels 5 when rotating, so that the planetary wheels 5 and the gear shaft 6 are more closely meshed, thereby reducing the return clearance of the RV reducer and improving the transmission accuracy of the RV reducer.

[0030] The unit of the return clearance is arc minute. In the reducer, a return clearance below 3 arc minutes is generally called a high-precision reducer, and a return clearance above 15 arc minutes is called a low-precision reducer. The return clearance of the RV reducer in this embodiment can be as low as 0.5 arc minutes, with extremely high transmission accuracy, and is suitable for high-precision machining.

[0031] In a specific embodiment, Figure 1-2 As shown, the needle teeth 301 and the needle tooth disk 3 are integrally formed to increase the transmission accuracy of the RV reducer and extend the service life of the RV reducer.

[0032] In one embodiment, if Figure 1-3 As shown, the RV reducer also includes: an end cover 7, a front housing 8 and a rear housing 9. The end cover 7 is used to provide support for the pinion gear 3. The front housing 8 and the rear housing 9 are respectively located at the two ends of the cycloid wheel 2, the front housing 8 is connected to the rear housing 9, and the rear housing 9 is connected to the end cover 7, and the crankshaft 1 and the gear shaft 6 can be rotatably mounted on the front housing 8 and the rear housing 9.

[0033] Specifically, the front housing 8 and the rear housing 9 are used to provide support force for the crankshaft 1 and the gear shaft 6 .

[0034] In one embodiment, if Figure 3-4As shown, the crankshaft 1 is installed on the front housing 8 and the rear housing 9 through the first bearing 10, so as to reduce the rotational friction between the crankshaft 1 and the front housing 8 and the rear housing 9, so that the crankshaft 1 rotates more smoothly, and the transmission accuracy of the RV reducer is further improved.

[0035] In one embodiment, if Figure 3-4 As shown, the gear shaft 6 is installed on the front housing 8 and the rear housing 9 through the second bearing 11, so as to reduce the rotational friction between the gear shaft 6 and the front housing 8 and the rear housing 9, so that the gear shaft 6 rotates more smoothly, further improving the transmission accuracy of the RV reducer.

[0036] In a specific embodiment, Figure 3-5 As shown, the front box body 8 and the rear box body 9 are detachably connected by screws 12 and nut columns 13.

[0037] Specifically, the connection mode of the screw 12 and the nut column 13 is not only simple in structure, but also reliable in connection and convenient in assembly and disassembly.

[0038] In one embodiment, if Figure 6 As shown, the driving mechanism 4 is installed on the rear box body 9.

[0039] Specifically, the RV reducer in this embodiment has a compact structure and a high degree of integration, which improves the space utilization of the RV reducer.

[0040] In one embodiment, if Figure 3 As shown, the RV reducer further includes a limiting assembly 14 , which is disposed on the crankshaft 1 and abuts against the planetary gear 5 to limit the movement of the planetary gear 5 along the axial direction of the crankshaft 1 .

[0041] Specifically, the limiting assembly 14 can prevent the planetary gear 5 from moving along the axial direction of the crankshaft 1, thereby affecting the transmission accuracy of the RV reducer and even causing the RV reducer to fail.

[0042] In a specific embodiment, Figure 3 As shown, the limiting assembly 14 includes: a sleeve 1401 and a retaining ring 1402. The sleeve 1401 is sleeved on the crankshaft 1, the sleeve 1401 abuts against the planetary gear 5 and is located at one end of the planetary gear 5 close to the driving mechanism 4. The retaining ring 1402 is sleeved on the crankshaft 1, the retaining ring 1402 abuts against the planetary gear 5 and is located at one end of the planetary gear 5 away from the sleeve 1401.

[0043] This embodiment uses a sleeve 1401 and a retaining ring 1402 to limit the planetary gear 5, and the structure is simple and reliable.

[0044] In one embodiment, if Figure 5-6 As shown, the driving mechanism 4 includes two first driving members 401, which are respectively used to drive the two crank shafts 1 to rotate.

[0045] By implementing this embodiment, each crank shaft 1 is individually driven by a first driving member 401, and the transmission accuracy is high, which is suitable for high-precision RV reducers. Therefore, this embodiment is a preferred embodiment.

[0046] In another embodiment, the driving mechanism 4 includes a second driving member (not shown in the figure) and a transmission assembly (not shown in the figure), the second driving member is connected to the transmission assembly, the transmission assembly is connected to one end of the two crank shafts 1, and the second driving member drives the transmission assembly to drive the two crank shafts to rotate 1.

[0047] In this embodiment, only one second driving member is needed to drive two crank shafts 1, and the energy consumption is low. However, because a transmission assembly is required for transmission, the transmission accuracy is low.

[0048] In one embodiment, if Figure 1-2 As shown, the RV reducer also includes a third crankshaft (not shown in the figure) and a third planetary gear (not shown in the figure). The middle part of the third crankshaft is also provided with a first eccentric segment 101 and a second eccentric segment 102. The driving mechanism 4 is connected to one end of the third crankshaft to drive the third crankshaft to rotate. The third planetary gear is installed at the other end of the third crankshaft, and the gear shaft 6 is meshed with the third planetary gear and driven thereby.

[0049] Specifically, compared with the embodiment in which two crank shafts 1 drive two planetary gears 5, this embodiment uses three planetary gears 5 to drive the gear shaft. The planetary gears can further press the gear shaft 6 to make the engagement between the two tighter, further reduce the return clearance of the RV reducer, and improve the transmission accuracy of the RV reducer.

[0050] Of course, it is understandable that the RV reducer can also include a fourth crankshaft (not shown in the figure) and a fourth planetary gear (not shown in the figure). Those skilled in the art can make adaptive adjustments to this. The present invention does not limit the number of crankshafts 1 and planetary gears 5.

[0051] In one embodiment, if Figure 1-2 As shown, the RV reducer also includes a third cycloid wheel (not shown in the figure), and the two crank shafts 1 are also provided with a third eccentric section (not shown in the figure), and the third cycloid wheel is installed on the third eccentric section of the two crank shafts 1.

[0052] Specifically, compared with the embodiment of two cycloid wheels 2, the RV reducer of this embodiment has the advantages of smoother transmission, more uniform force, high torsional stiffness, high precision, low noise, strong load-bearing capacity and long life.

[0053] Of course, it is understandable that the RV reducer can also include a fourth cycloid wheel (not shown in the figure), and a fourth eccentric segment (not shown in the figure) can be provided on the crankshaft 1. Those skilled in the art can make adaptive adjustments to this, and the present invention is not limited thereto.

[0054] In one embodiment, if Figure 7 As shown, the RV reducer further includes an output disk 15 , which is connected to the pin-tooth disk 3 , and the RV reducer outputs power through the output disk 15 .

[0055] In one embodiment, if Figure 4-5 As shown, a third bearing 16 is further provided between the end cover 7 and the needle toothed disc 3 .

[0056] Specifically, the third bearing 16 can reduce the rotational friction between the end cover 7 and the pinion gear disc 3, making the pinion gear disc 3 rotate more smoothly, further improving the transmission accuracy of the RV reducer.

[0057] In one embodiment, if Figure 1 , 5 As shown, the bottom of the needle tooth disk 3 is provided with a first annular extension section 302 extending toward the bottom box 9, the rear box 9 is provided with a second annular extension section 901 extending toward the cycloidal wheel 2, and a fourth bearing 17 is provided between the first annular extension section 302, the second annular extension section 901 and the needle tooth disk 3.

[0058] Specifically, the fourth bearing 17 can improve the stability of the pin-toothed disc 3 during rotation, and further improve the transmission accuracy of the RV reducer.

[0059] In a specific embodiment, Figure 5 As shown, a cushion block 18 is further provided at the bottom of the fourth bearing 17 , and the cushion block 18 can limit the relative position of the fourth bearing 17 to prevent it from being offset, so as to ensure that the pin-toothed disc 3 can rotate stably.

[0060] The embodiment of the present invention shows an RV reducer, such as Figure 1-2 As shown, the two crankshafts 1 are driven to rotate by the driving mechanism 4, thereby driving the two cycloidal wheels 2 to swing, and the cycloidal wheels 2 are meshed with the needle teeth 301 on the inner circumference of the pinion plate 3, thereby driving the pinion plate 3 to rotate. When the driving mechanism 4 drives the two crankshafts 1 to rotate, it will simultaneously drive the planetary wheels 5 installed on the two crankshafts 1 to rotate, and then drive the gear shaft 6 meshed with the planetary wheels 5 to rotate. Since the planetary wheels 5 located around the gear shaft 6 are driving wheels, the gear shaft 6 located in the middle will be subjected to pressure from the planetary wheels 5 when rotating, so that the planetary wheels 5 and the gear shaft 6 are meshed very tightly, thereby reducing the return clearance of the RV reducer, improving the transmission accuracy of the RV reducer, and making the RV reducer suitable for high-precision machining.

[0061] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the protection scope of the claims attached to the present invention.

Claims

1. An RV reducer, characterized in that: include: At least two crankshafts, each having a first eccentric section and a second eccentric section; At least two cycloid wheels, one of which is mounted on the first eccentric section of the two crankshafts, and the other cycloid wheel is mounted on the second eccentric section of the two crankshafts; A pin-toothed disc, the inner circumference of which is provided with a plurality of pin-teeth meshing with the two cycloid wheels; A driving mechanism, comprising two first driving members, wherein the two first driving members are respectively connected to one end of the two crank shafts to drive the two crank shafts to rotate; At least two planetary gears, which are respectively mounted on the other ends of the two crankshafts; A gear shaft, which is rotatably disposed on the two pinion gears, the planetary gears are evenly distributed on a circle with the center of the gear shaft as the center, the gear shaft is meshed with the two planetary gears and is driven by the two planetary gears; A limit assembly is provided on the crankshaft and abuts against the planetary gear to limit the movement of the planetary gear along the axial direction of the crankshaft; the limit assembly includes a sleeve and a retaining ring, the sleeve is sleeved on the crankshaft, the sleeve abuts against the planetary gear and is located at an end of the planetary gear close to the driving mechanism; the retaining ring is sleeved on the crankshaft, the retaining ring abuts against the planetary gear and is located at an end of the planetary gear away from the sleeve.

2. The RV reducer according to claim 1, characterized in that: The needle teeth are integrally formed with the needle tooth disc.

3. The RV reducer according to claim 1, characterized in that: Also includes: An end cover, a front box body and a rear box body, wherein the end cover is used to provide support force for the needle toothed disk, the front box body and the rear box body are respectively located at the two ends of the cycloidal wheel, the front box body is connected to the rear box body, and the rear box body is connected to the end cover, and the crank shaft and the gear shaft can be rotatably mounted on the front box body and the rear box body.

4. The RV reducer according to claim 3, characterized in that: The driving mechanism is mounted on the rear box body and is located at an end of the rear box body away from the cycloid wheel.

5. The RV reducer according to any one of claims 1 to 4, characterized in that: The driving mechanism includes a second driving member and a transmission assembly, the second driving member is connected to the transmission assembly, the transmission assembly is connected to one end of the two crank shafts, and the second driving member drives the transmission assembly to drive the two crank shafts to rotate.

6. The RV reducer according to any one of claims 1 to 4, characterized in that: Also includes: A third crankshaft, wherein the first eccentric segment and the second eccentric segment are also provided at the middle thereof, and the driving mechanism is connected to one end of the third crankshaft to drive the third crankshaft to rotate; The third planetary gear is mounted on the other end of the third crank shaft, and the gear shaft is meshed with and driven by the third planetary gear.

7. The RV reducer according to any one of claims 1 to 4, characterized in that: It also includes a third cycloid wheel. The two crank shafts are also provided with a third eccentric section. The third cycloid wheel is installed on the third eccentric section of the two crank shafts.

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