阅读说明：本技术 摆线型减速机 (Cycloidal speed reducer ) 是由 钟启闻 朱恩毅 林泓玮 曹明立 于 2019-12-27 设计创作，主要内容包括：本发明提供一种摆线型减速机,包含两组转盘组,且每一转盘组包含两个摆线盘,故本发明的摆线型减速机可利用四个摆线盘与对应滚柱相接触,使每一摆线盘所承受的负荷减少,使摆线型减速机具有较强结构强度。此外,本发明的摆线型减速机的偏心组件包含以偏心方式设置于转轴上的多个偏心圆柱,每一偏心圆柱设置于对应摆线盘的轴孔内,且多个偏心圆柱使两个摆线盘的偏心方向与其余两个摆线盘的偏心方向相反,使得摆线型减速机在作动时可达成动平衡。再者,本发明的摆线型减速机直接利用连接件穿设各摆线盘的摆线盘孔,使摆线型减速机易于组装。(The invention provides a cycloidal speed reducer, which comprises two groups of rotating disc sets, wherein each rotating disc set comprises two cycloidal discs, so that the cycloidal speed reducer can utilize four cycloidal discs to be in contact with corresponding rollers, the load borne by each cycloidal disc is reduced, and the cycloidal speed reducer has stronger structural strength. In addition, the eccentric assembly of the cycloidal speed reducer comprises a plurality of eccentric cylinders eccentrically arranged on the rotating shaft, each eccentric cylinder is arranged in the shaft hole of the corresponding cycloidal disc, and the eccentric directions of two cycloidal discs are opposite to the eccentric directions of the other two cycloidal discs by the plurality of eccentric cylinders, so that the cycloidal speed reducer can achieve dynamic balance during actuation. In addition, the cycloidal speed reducer directly utilizes the connecting piece to penetrate through the cycloidal disc holes of each cycloidal disc, so that the cycloidal speed reducer is easy to assemble.)

1. A cycloidal reducer comprising:

the eccentric device comprises a rotating shaft and an eccentric assembly, the rotating shaft can rotate, the eccentric assembly is eccentrically and fixedly arranged on the rotating shaft and positioned between a first end and a second end of the rotating shaft, and the eccentric assembly is driven by the rotating shaft to deflect relative to an axis of the rotating shaft;

the first roller wheel disc group comprises a first wheel disc and a plurality of first rollers, and the first rollers are arranged on the first wheel disc;

the second roller wheel disc group comprises a second wheel disc and a plurality of second rollers, and the second rollers are arranged on the second wheel disc;

the first rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises two adjacent cycloid discs, each cycloid disc comprises at least one outer convex tooth part and at least one cycloid disc hole, and the outer convex tooth part is contacted with at least one corresponding first roller;

the second rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises two adjacent cycloid discs, the cycloid disc of each second rotating disc group comprises at least one outer convex tooth part and at least one cycloid disc hole, the outer convex tooth part of the second rotating disc group is contacted with at least one corresponding second roller, and the cycloid disc hole of the second rotating disc group is corresponding to the cycloid disc hole of the first rotating disc group; and

at least one connecting piece, which penetrates through the cycloid disc hole of each cycloid disc of the first rotating disc group and the cycloid disc hole of each cycloid disc of the second rotating disc group, wherein the connecting piece penetrates through each part of each cycloid disc hole and has the same diameter;

the diameter of the cycloid disc hole of one of the cycloid discs of the first turntable group and the diameter of the cycloid disc hole of one of the cycloid discs of the second turntable group are equal to the diameter of the connecting piece, and the diameter of the cycloid disc hole of the other cycloid disc of the first turntable group and the diameter of the cycloid disc hole of the other cycloid disc of the second turntable group are larger than the diameter of the connecting piece.

2. The cycloidal reducer according to claim 1 wherein said two cycloidal discs of said first set of discs are a first epicycloidal disc and a first hypocycloidal disc, said first epicycloidal disc comprising at least a first epicycloidal disc hole, said first hypocycloidal disc comprising at least a first hypocycloidal disc hole, said two cycloidal discs of said second set of discs are a second hypocycloidal disc and a second epicycloidal disc, said second hypocycloidal disc comprising at least a second hypocycloidal disc hole, said second epicycloidal disc comprising at least a second epicycloidal disc hole, said first hypocycloidal disc hole and said second hypocycloidal disc hole having diameters equal to a diameter of said connecting member, said first epicycloidal disc hole and said second epicycloidal disc hole having diameters greater than a diameter of said connecting member.

3. The cycloidal reducer according to claim 1 wherein said two cycloidal discs of said first set of discs are a first epicycloidal disc and a first hypocycloidal disc, said first epicycloidal disc comprising at least a first epicycloidal disc hole, said first hypocycloidal disc comprising at least a first hypocycloidal disc hole, said two cycloidal discs of said second set of discs are a second hypocycloidal disc and a second epicycloidal disc, said second hypocycloidal disc comprising at least a second hypocycloidal disc hole, said second epicycloidal disc comprising at least a second epicycloidal disc hole, said first epicycloidal disc hole and said second epicycloidal disc hole having diameters equal to the diameter of said connecting member, said first hypocycloidal disc hole and said second hypocycloidal disc hole having diameters greater than the diameter of said connecting member.

4. The cycloidal reducer according to claim 1 wherein said two cycloidal discs of said first set of discs are a first epicycloidal disc and a first hypocycloidal disc, said first epicycloidal disc comprising at least a first epicycloidal disc hole, said first hypocycloidal disc comprising at least a first hypocycloidal disc hole, said two cycloidal discs of said second set of discs are a second hypocycloidal disc and a second epicycloidal disc, said second hypocycloidal disc comprising at least a second hypocycloidal disc hole, said second epicycloidal disc comprising at least a second epicycloidal disc hole, said first hypocycloidal disc hole and said second hypocycloidal disc hole having diameters equal to a diameter of said connecting member, said first epicycloidal disc hole and said second hypocycloidal disc hole having diameters greater than a diameter of said connecting member.

5. The cycloidal reducer according to claim 1 wherein said two cycloidal discs of said first set of discs are a first epicycloidal disc and a first hypocycloidal disc, said first epicycloidal disc comprising at least a first epicycloidal disc hole, said first hypocycloidal disc comprising at least a first hypocycloidal disc hole, said two cycloidal discs of said second set of discs are a second hypocycloidal disc and a second epicycloidal disc, said second hypocycloidal disc comprising at least a second hypocycloidal disc hole, said second epicycloidal disc comprising at least a second epicycloidal disc hole, said first epicycloidal disc hole and said second hypocycloidal disc hole having diameters equal to the diameter of said connecting member, said first hypocycloidal disc hole and said second epicycloidal disc hole having diameters greater than the diameter of said connecting member.

6. The cycloidal reducer of claim 1 wherein the diameter of the cycloidal disk hole of the first set of cycloidal disks having the relatively larger diameter is equal to the diameter of the connecting member plus four times the eccentricity of the eccentric member with respect to the axis of the rotating shaft, and the diameter of the cycloidal disk hole of the second set of cycloidal disks having the relatively larger diameter is equal to the diameter of the connecting member plus four times the eccentricity of the eccentric member with respect to the axis of the rotating shaft.

7. The cycloidal reducer of claim 1 wherein the eccentricity directions of the two cycloidal discs of the first set of discs are opposite and the eccentricity directions of the two cycloidal discs of the second set of discs are opposite.

8. A cycloidal reducer comprising:

the eccentric device comprises a rotating shaft and an eccentric assembly, the rotating shaft can rotate, the eccentric assembly is eccentrically and fixedly arranged on the rotating shaft and positioned between a first end and a second end of the rotating shaft, and the eccentric assembly is driven by the rotating shaft to deflect relative to an axis of the rotating shaft;

the first roller wheel disc group comprises a first wheel disc and a plurality of first rollers, and the first rollers are arranged on the first wheel disc;

the second roller wheel disc group comprises a second wheel disc and a plurality of second rollers, and the second rollers are arranged on the second wheel disc;

the first rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises a first epicycloid disc and a first hypocycloid disc which are adjacently arranged, the first epicycloid disc comprises at least one outer convex tooth part and at least one first epicycloid disc hole, the first hypocycloid disc comprises at least one outer convex tooth part and at least one first hypocycloid disc hole, and the outer convex tooth parts of the first epicycloid disc and the first hypocycloid disc are respectively contacted with at least one corresponding first roller;

the second rotating disc set is arranged on the eccentric assembly and is driven by the eccentric assembly to rotate, and comprises a second epicycloid disc and a second hypocycloid disc which are adjacently arranged, the second epicycloid disc comprises at least one outer convex tooth part and at least one second outer cycloid disc hole, the second hypocycloid disc comprises at least one outer convex tooth part and at least one second hypocycloid disc hole, the outer convex tooth parts of the second epicycloid disc and the second hypocycloid disc are respectively contacted with at least one corresponding second roller, and the first epicycloid disc hole, the first hypocycloid disc hole, the second outer cycloid disc hole and the second hypocycloid disc hole are corresponding; and

at least one connecting piece, which is arranged in the first epicycloid disc hole, the first hypocycloid disc hole, the second epicycloid disc hole and the second hypocycloid disc hole in a penetrating way, wherein the connecting piece is tightly attached to the wall surfaces of the first epicycloid disc hole, the first hypocycloid disc hole, the second epicycloid disc hole and the second hypocycloid disc hole in the penetrating way;

the diameter of the first hypocycloid disc hole is equal to that of the second hypocycloid disc hole, the diameter of the first epicycloid disc hole is equal to that of the second epicycloid disc hole, and the diameters of the first hypocycloid disc hole and the second hypocycloid disc hole are larger than those of the first epicycloid disc hole and the second epicycloid disc hole.

9. The cycloidal reducer of claim 8 wherein the connecting member includes a first through-hole, a second through-hole and a third through-hole, which are sequentially connected, the first through-hole and the third through-hole respectively passing through the first epicycloidal disc hole and the second epicycloidal disc hole, the second through-hole passing through the first hypocycloidal disc hole and the second hypocycloidal disc hole.

10. The cycloidal reducer according to claim 9 wherein an offset exists between the axis of the second through-hole and the axes of the first through-hole and the third through-hole.

11. The cycloidal reducer according to claim 10 wherein the amount of eccentricity between the first epicycloidal disc and the first hypocycloidal disc is equal to the amount of eccentricity between the second epicycloidal disc and the second epicycloidal disc, and the amount of eccentricity between the axes of the second penetration portion and the axes of the first penetration portion and the third penetration portion is equal to twice the amount of eccentricity between the first epicycloidal disc and the first hypocycloidal disc.

12. The cycloidal reducer of claim 8 wherein the eccentricity directions of the two cycloidal discs of the first set of discs are opposite and the eccentricity directions of the two cycloidal discs of the second set of discs are opposite.

Technical Field

The present invention relates to a speed reducer, and more particularly, to a cycloidal speed reducer having high rigidity and capable of achieving dynamic balance.

Background

Generally, a motor has a characteristic of high rotation speed and small torque, so that it is difficult to drive a large load, and when the motor is used to push a heavy object, a speed reducer is used to reduce the speed, thereby increasing the torque.

Common speed reducers include rv (rotational vector) speed reducers, Harmonic speed reducers (Harmonic Drive), cycloidal speed reducers, and the like. An RV reducer, such as an RV-E series reducer manufactured by Nabtesco, japan, is of a two-stage reduction type, which includes a first reduction part that is a spur gear reduction mechanism and a second reduction part that is a differential gear reduction mechanism, wherein gears in the first reduction part and the second reduction part may be respectively composed of metal elements, and the series of reducers can simultaneously reduce vibration and inertia at the time of increasing an acceleration-reduction ratio by a two-stage reduction design. Although RV reducers have excellent performance in terms of high rigidity and high reduction ratio, and rolling contact elements in RV reducers can also ensure high product efficiency and long life, their volume and weight are relatively large, and their components are relatively numerous, difficult to assemble, and result in relatively high cost of RV reducers.

The harmonic reducer is mainly composed of a wave generator, a flexible gear and a rigid gear, and the harmonic transmission of the harmonic reducer utilizes the elastic micro-deformation of the flexible gear to perform pushing operation, so as to transmit motion and power. Although the harmonic reducer has the advantages of small size, light weight and high precision compared with the RV reducer, the harmonic reducer has poor rigidity due to the flexible gear of the harmonic reducer, so the harmonic reducer is not impact-resistant and has the problem of tooth difference friction, resulting in a short service life.

The cycloidal reducer comprises an eccentric shaft and two cycloidal disks which comprise at least one tooth part and are respectively linked with a power input shaft and a power output shaft, and the operation principle is that the input shaft drives one of the cycloidal disks to rotate through the eccentric shaft, the other cycloidal disk correspondingly drives the output shaft to rotate, and the rotation of the two cycloidal disks is actually realized by utilizing the corresponding tooth part structures. Although the traditional cycloidal speed reducer has the advantages of large transmission ratio, compact structure and high transmission efficiency, when the traditional cycloidal speed reducer is applied to occasions bearing high loads, namely, two cycloidal disks of the traditional cycloidal speed reducer need to bear the high loads, so that if the structural strength of the two cycloidal disks is not enough, the cycloidal disks can be damaged, and the traditional cycloidal speed reducer cannot normally operate. In addition, the use of the eccentric shaft of the traditional cycloid speed reducer causes the cycloid disc to deviate to a specific direction to rotate when the cycloid speed reducer operates, so if the traditional cycloid speed reducer is provided with a deviation weight compensation device for dynamic balance compensation without extra cost, the traditional cycloid speed reducer cannot reach dynamic balance when operating and has the problem of larger vibration when operating.

Therefore, how to develop a cycloidal reducer that can improve the above-mentioned drawbacks of the prior art, and that has the characteristics of both RV reducer and harmonic reducer, and that can achieve high rigidity, easy assembly and dynamic balance is a problem that those skilled in the related art are currently in urgent need to solve.

Disclosure of Invention

The invention aims to provide a cycloidal reducer, which solves the defects of relatively large volume and weight, difficult assembly, relatively high cost and the like of the traditional RV reducer and simultaneously solves the defects of impact intolerance, tooth difference friction and the like of the traditional harmonic reducer. In addition, the cycloidal speed reducer disclosed by the invention has the advantages of high rigidity, easiness in assembly and dynamic balance.

To achieve the above objective, a broader aspect of the present invention provides a cycloidal reducer, including an eccentric device, a first roller pulley set, a second roller pulley set, a first turntable set, a second turntable set, and at least one connecting member, wherein the eccentric device includes a rotating shaft and an eccentric assembly, the rotating shaft is rotatable, the eccentric assembly is eccentrically fixed on the rotating shaft and located between a first end and a second end of the rotating shaft, and is driven by the rotating shaft to deflect relative to an axis of the rotating shaft; the first roller wheel disc group comprises a first wheel disc and a plurality of first rollers, and the first rollers are arranged on the first wheel disc; the second roller wheel disc group comprises a second wheel disc and a plurality of second rollers, and the plurality of second rollers are arranged on the second wheel disc; the first rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises two adjacent cycloid discs, each cycloid disc comprises at least one outer convex tooth part and at least one cycloid disc hole, and the outer convex tooth part is contacted with at least one corresponding first roller; the second rotating disc group is arranged on the eccentric assembly and is driven by the eccentric assembly to rotate, the second rotating disc group comprises two adjacent cycloid discs, each cycloid disc of the second rotating disc group comprises at least one outer convex tooth part and at least one cycloid disc hole, the outer convex tooth part of the second rotating disc group is contacted with at least one corresponding second roller, and the cycloid disc hole of the second rotating disc group corresponds to the cycloid disc hole of the first rotating disc group; the connecting piece is used for penetrating through the cycloid disc holes of each cycloid disc of the first turntable group and the cycloid disc holes of each cycloid disc of the second turntable group, and all parts of the connecting piece penetrating through the cycloid disc holes are the same in diameter; the diameters of the cycloid disc holes of one cycloid disc of the first turntable group and one cycloid disc hole of one cycloid disc of the second turntable group are equal to the diameter of the connecting piece, and the diameters of the cycloid disc holes of the other cycloid disc of the first turntable group and the cycloid disc hole of the other cycloid disc of the second turntable group are larger than the diameter of the connecting piece.

In order to achieve the above objectives, another broader aspect of the present invention provides a cycloidal reducer, including an eccentric device, a first roller pulley set, a second roller pulley set, a first rotating pulley set, a second rotating pulley set, and at least one connecting member, wherein the eccentric device includes a rotating shaft and an eccentric assembly, the rotating shaft is rotatable, the eccentric assembly is eccentrically fixed on the rotating shaft and located between a first end and a second end of the rotating shaft, and is driven by the rotating shaft to deflect relative to an axis of the rotating shaft; the first roller wheel disc group comprises a first wheel disc and a plurality of first rollers, and the first rollers are arranged on the first wheel disc; the second roller wheel disc group comprises a second wheel disc and a plurality of second rollers, and the plurality of second rollers are arranged on the second wheel disc; the first rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises a first epicycloid disc and a first hypocycloid disc which are adjacently arranged, the first epicycloid disc comprises at least one outer convex tooth part and at least one first epicycloid disc hole, the first hypocycloid disc comprises at least one outer convex tooth part and at least one first hypocycloid disc hole, and the outer convex tooth parts of the first epicycloid disc and the first hypocycloid disc are respectively contacted with at least one corresponding first roller; the second rotating disc group is arranged on the eccentric assembly and driven by the eccentric assembly to rotate, and comprises a second epicycloid disc and a second hypocycloid disc which are adjacently arranged, the second epicycloid disc comprises at least one outer convex tooth part and at least one second epicycloid disc hole, the second hypocycloid disc comprises at least one outer convex tooth part and at least one second hypocycloid disc hole, the outer convex tooth parts of the second epicycloid disc and the second hypocycloid disc are respectively contacted with at least one corresponding second roller, and the first epicycloid disc hole, the first hypocycloid disc hole, the second epicycloid disc hole and the second hypocycloid disc hole are corresponding; the connecting piece is used for penetrating the first epicycloid disc hole, the first hypocycloid disc hole, the second epicycloid disc hole and the second hypocycloid disc hole, and the connecting piece is tightly attached to the wall surfaces of the first epicycloid disc hole, the first hypocycloid disc hole, the second epicycloid disc hole and the second hypocycloid disc hole; the diameter of the first hypocycloid disc hole is equal to that of the second hypocycloid disc hole, the diameter of the first epicycloid disc hole is equal to that of the second epicycloid disc hole, and the diameters of the first hypocycloid disc hole and the second hypocycloid disc hole are larger than those of the first epicycloid disc hole and the second epicycloid disc hole.

The cycloidal speed reducer comprises two groups of rotating disc groups, and each rotating disc group comprises two cycloidal discs, so that the cycloidal speed reducer can utilize four cycloidal discs to contact with corresponding rollers, and the load borne by each cycloidal disc can be reduced.

Drawings

Fig. 1 is a schematic view of a cycloidal reducer according to a first preferred embodiment of the present invention.

Fig. 2A and 2B are schematic views of the explosion structure of the cycloidal reducer shown in fig. 1 at different viewing angles.

FIG. 2C is a schematic view of an assembly structure of the eccentric device, the first rotating disk set and the second rotating disk set shown in FIG. 1.

Fig. 2D is a schematic cross-sectional view of the cycloidal reducer shown in fig. 1.

Fig. 2E is a schematic structural diagram of the eccentric device and a bearing set shown in fig. 2A.

Fig. 2F is a schematic size diagram of the first epicycloidal disc hole and the connecting piece of the first epicycloidal disc of the cycloidal reducer shown in fig. 1.

Fig. 3A is a schematic view of an assembly structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal reducer according to a second preferred embodiment of the invention.

Fig. 3B is a schematic cross-sectional view of a cycloidal reducer according to a second preferred embodiment of the invention.

Fig. 4A is a schematic cross-sectional view of a cycloidal reducer according to a third preferred embodiment of the invention.

Fig. 4B is a schematic cross-sectional view of a connecting member of a cycloidal reducer according to a third preferred embodiment of the invention.

Fig. 5A is a schematic view of an assembly structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal reducer according to a fourth preferred embodiment of the invention.

Fig. 5B is a schematic cross-sectional view of a cycloidal reducer according to a fourth preferred embodiment of the invention.

Fig. 5C is a schematic structural diagram of an eccentric device and a bearing set of a cycloidal reducer according to a fourth preferred embodiment of the invention.

Fig. 6A is a schematic view of an assembly structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal reducer according to a fifth preferred embodiment of the invention.

Fig. 6B is a schematic cross-sectional view of a cycloidal reducer according to a fifth preferred embodiment of the invention.

The reference numbers are as follows:

1. 1a, 1b, 1c, 1 d: cycloidal speed reducer

2: eccentric device

20: rotating shaft

200: first end

201: second end

21: eccentric assembly

22a, 22 b: first eccentric cylinder

23a, 23 b: second eccentric cylinder

24a, 24 b: third eccentric cylinder

25: fourth eccentric cylinder

3: first roller wheel disc set

30: first wheel disc

31: a first roller

32: casing body

300. 400: center hole

4: second roller wheel set

40: second wheel disc

41: second roller

5: first rotating disk group

50: first outer cycloid disk

501: first outer convex tooth part

502: first epicycloidal disk hole

503: first shaft hole

51: first hypocycloidal disc

511: second convex tooth part

512: first hypocycloid disc hole

513: second shaft hole

52: connecting piece

521: first penetrating part

522: second penetrating part

523: third penetrating part

6: the second rotary table group

60: second hypocycloidal disc

601: third outer convex tooth part

602: second hypocycloid disc hole

603: third shaft hole

61: second outer cycloid dish

611: fourth convex tooth part

612: second epicycloidal disk hole

613: fourth shaft hole

8: bearing set

80a, 80 b: fourth bearing

90: first bearing

91: second bearing

92: third bearing

A. c: center of circle

b: axial center

R, R: radius of

e: eccentricity of the cylinder

Detailed Description

Some exemplary embodiments that embody features and advantages of the invention will be described in detail in the description that follows. As will be realized, the invention is capable of other and different modifications and its several details are capable of modifications in various obvious respects, all without departing from the scope of the invention, and the description and drawings are to be regarded as illustrative in nature, and not as restrictive.

Referring to fig. 1, fig. 2A, fig. 2B, fig. 2C and fig. 2D, fig. 2E and fig. 2F, wherein fig. 1 is a schematic diagram of an assembly structure of a cycloidal reducer according to a first preferred embodiment of the present invention, fig. 2A and fig. 2B are schematic diagrams of an explosion structure of the cycloidal reducer shown in fig. 1 at different viewing angles, fig. 2C is a schematic diagram of an assembly structure of an eccentric device, a first rotating disc set and a second rotating disc set shown in fig. 1, fig. 2D is a schematic diagram of an exemplary cross-sectional structure of the cycloidal reducer shown in fig. 1, fig. 2E is a schematic diagram of a structure of the eccentric device and a bearing set shown in fig. 2A, and fig. 2F is a schematic diagram of sizes of a first epicycloidal disc hole and a connecting member of a first epicycloidal disc of a first. As shown in fig. 1, fig. 2A, fig. 2B, fig. 2C and fig. 2D, fig. 2E and fig. 2F, the cycloidal reducer 1 of the present embodiment can be applied, but not limited, to various motor devices, machine tools, mechanical arms, automobiles, locomotives or other power machines to provide a proper speed reduction function, and in addition, the cycloidal reducer 1 actually belongs to a two-step cycloidal reducer. The cycloidal reducer 1 comprises an eccentric device 2, a first roller wheel disc group 3, a second roller wheel disc group 4, a first rotating disc group 5, a second rotating disc group 6 and at least one connecting piece 52.

The eccentric device 2 receives power input from a motor (not shown), for example, and is driven to rotate by the power input, and includes a rotating shaft 20 and an eccentric assembly 21. The shaft 20 receives power input from a motor (not shown) and has a first end 200 and a second end 201 opposite to each other. The eccentric element 21 is eccentrically fixed to the rotating shaft 20 (i.e. the center of rotation of the eccentric element 21 is not the axis of the rotating shaft 20), is located between the first end 200 and the second end 201 of the rotating shaft, and is driven by the rotating shaft 20 to deflect relative to the axis of the rotating shaft 20. The eccentric element 21 includes a plurality of eccentric cylinders disposed on the rotating shaft 20 in an eccentric manner and adjacent to each other in sequence, and each eccentric cylinder is opposite to the adjacent eccentric cylinder in eccentric direction.

The first roller disk group 3 has a first disk 30 and a plurality of first rollers 31. The first wheel disc 30 is made of a circular disc-shaped element or a hollow cylindrical cage-shaped element made of metal or alloy, and the first wheel disc 30 has a center hole 300 at the geometric center thereof, the center hole 300 may be provided with a first bearing 90 (as shown in fig. 2D), the form of the first bearing 90 is not limited to a ball bearing, a needle bearing, an oil bearing, or the like, for example, so that the rotating shaft 20 is partially received in the center hole 300 of the first wheel disc 30 by the first bearing 90, and the first end 200 and the second end 201 of the rotating shaft 20 are located at opposite sides of the first wheel disc 30, respectively. The first rollers 31 may be, but are not limited to, short cylinders made of metal or alloy, and are arranged on the first wheel disc 30 at equal intervals and on the same side of the first wheel disc 30 as the second end 201. In addition, the first roller disc group 3 does not rotate about the axis of the rotating shaft 20, in other words, neither the first disc 30 nor the plurality of first rollers 31 can rotate about the axis of the rotating shaft 20. However, the plurality of first rollers 31 can rotate on their own axes, i.e., rotate on their own axes.

In some embodiments, the first roller disc set 3 further includes a housing 32, the housing 32 is connected to the first wheel disc 30 and has a hollow structure, and when the eccentric device 2, the first roller disc set 3, the second roller disc set 4, the first rotating disc set 5, and the second rotating disc set 6 are combined into the cycloidal reducer 1, as shown in fig. 1, the hollow structure of the housing 32 can accommodate at least a portion of the eccentric device 2, the second roller disc set 4, the first rotating disc set 5, the second rotating disc set 6, and the connecting member 52.

The second roller wheel disk group 4 has a second wheel disk 40 and a plurality of second rollers 41. The second wheel disc 40 may also be a circular disc-shaped element or a hollow cylindrical cage-shaped element made of metal or alloy, and the second wheel disc 40 has a central hole 400 at the geometric center thereof, the central hole 400 may be provided with a second bearing 91 (as shown in fig. 2D), the form of the second bearing 91 is not limited to ball bearings, needle bearings or oil bearings, etc., so that the rotating shaft 20 is partially received in the central hole 400 of the second wheel disc 40 by the second bearing 91, and the first end 200 and the second end 201 of the rotating shaft 20 are located at two opposite sides of the second wheel disc 40, respectively. The second rollers 41 may be, but not limited to, short cylinders made of metal or alloy, and are arranged in equidistant circles on the second wheel 40. In the present embodiment, the second roller pulley set 4 can rotate around the axis of the rotating shaft 20, in other words, the second pulley 40 and the plurality of second rollers 41 can rotate around the axis of the rotating shaft 20, and the second pulley 40 is actually the power output of the cycloidal reducer 1. In some embodiments, the second rollers 41 can rotate around their own axes.

In some embodiments, the cycloidal reducer 1 further includes a third bearing 92 (shown in fig. 2D) disposed in the hollow structure of the housing portion 32 and located between the housing portion 32 and the second wheel 40, so that the second roller wheel set 4 can rotate in the housing portion 32.

The first rotating disc set 5 is disposed on the eccentric assembly 21 and driven by the eccentric assembly 21 to rotate, and includes a first epicycloidal disc 50 and a first hypocycloidal disc 51. The first epicycloidal disc 50 is disposed adjacent to the first wheel disc 30, and includes at least one first external toothed portion 501 and at least one first epicycloidal disc hole 502, the first external toothed portion 501 is formed by protruding from the outer peripheral wall surface of the first epicycloidal disc 50, and contacts with the corresponding first roller 31. The first inner cycloid disc 51 and the first outer cycloid disc 50 are arranged adjacently, and the first inner cycloid disc 51 and the first wheel disc 30 are respectively located on two opposite sides of the first outer cycloid disc 50. The first hypocycloidal disc 51 includes at least one second epicycloidal tooth portion 511 and at least one first hypocycloidal disc hole 512, and the second epicycloidal tooth portion 511 is formed by protruding from the outer peripheral wall surface of the first hypocycloidal disc 51 and contacts with the corresponding first roller 31. In addition, the first outer cycloid discs 50 and the first inner cycloid discs 51 are disposed on two eccentric cylinders of the eccentric assembly 21, which have opposite eccentric directions, so that the eccentric directions of the first outer cycloid discs 50 and the first inner cycloid discs 51 are opposite.

The second rotating disc set 6 is disposed on the eccentric assembly 21 and driven by the eccentric assembly 21 to rotate, and includes a second inner cycloid disc 60 and a second outer cycloid disc 61. The second inner cycloid disc 60 is disposed between the first inner cycloid disc 51 and the second wheel disc 40, and includes at least one third outer tooth portion 601 and at least one second inner cycloid disc hole 602, the third outer tooth portion 601 is formed by protruding from the outer circumferential wall surface of the second inner cycloid disc 60, and contacts with the corresponding second roller 41. The second epicycloidal disc 61 is disposed between the second epicycloidal disc 60 and the second wheel disc 40, and includes at least one fourth externally-protruding tooth portion 611 and at least one second epicycloidal disc hole 612, and the fourth externally-protruding tooth portion 611 is formed by protruding from the outer peripheral wall surface of the second epicycloidal disc 61 and contacts with the corresponding second roller 41. In addition, the second epicycloidal disc 61 and the second hypocycloidal disc 60 are disposed on two eccentric cylinders of the eccentric unit 21, which have opposite eccentric directions, so that the eccentric directions of the second epicycloidal disc 61 and the second hypocycloidal disc 60 are opposite.

In the above embodiment, the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second hypocycloidal disc hole 602, and the second epicycloidal disc hole 612 are located correspondingly and have the same number as the connecting members 52. The connector 52 is located between the first epicycloidal disc 50 and the second epicycloidal disc 61 and passes through the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602 and second epicycloidal disc hole 612. Furthermore, the diameters of the first and second hypocycloidal disc holes 512, 602 are substantially equal to the diameter of the connecting member 52 (to cover the tolerance), while the diameter of the first epicycloidal disc hole 502 is equal to the diameter of the second epicycloidal disc hole 612, and the diameters of the first and second epicycloidal disc holes 502, 612 are larger than the diameter of the connecting member 52. Therefore, when the connecting element 52 is inserted into the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602 and second epicycloidal disc hole 612, the diameters of the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602 are substantially equal to the diameter of the connecting element 52, so that the first hypocycloidal disc 51 and the second hypocycloidal disc 60 can be assembled by the connecting element 52, and the diameter of the first epicycloidal disc hole 502 and the diameter of the second epicycloidal disc hole 612 are larger than the diameter of the connecting element 52, so that the connecting element 52 is only contacted with part of the wall surface of the corresponding first epicycloidal disc hole 502 and second epicycloidal disc hole 612. Furthermore, since the diameter of the first epicycloidal disc hole 502 is larger than the diameter of the connecting member 52, and the diameter of the first hypocycloidal disc hole 512 is substantially equal to the diameter of the connecting member 52, when the first epicycloidal disc 50 and the first hypocycloidal disc 51 rotate, the first epicycloidal disc 50 and the first hypocycloidal disc 51 can still rotate in opposite eccentric directions, and the first epicycloidal disc 50 and the first hypocycloidal disc 51 can be prevented from interfering with each other. Similarly, due to the diameter relationship between the second hypocycloid disc hole 602 and the second epicycloid disc hole 612, when the cycloid disc rotates, the second hypocycloid disc 60 and the second epicycloid disc 61 can still rotate in opposite eccentric directions, and the second hypocycloid disc 60 and the second epicycloid disc 61 can be prevented from interfering with each other.

In some embodiments, the first epicycloidal disc 50 comprises a first shaft bore 503 and the first epicycloidal disc 51 comprises a second shaft bore 513. The first axial hole 503 and the second axial hole 513 are respectively disposed at the geometric center positions of the first epicycloidal disc 50 and the first hypocycloidal disc 51, and a portion of the eccentric assembly 21 is rotatably disposed in the first axial hole 503 and the second axial hole 513, so that when the eccentric device 2 rotates, the first epicycloidal disc 50 and the first hypocycloidal disc 51 are driven by the eccentric assembly 21 of the eccentric device 2 to rotate.

As shown in fig. 2F, taking the first epicycloidal disc hole 502 of the first epicycloidal disc 50 as an example, in some embodiments, when the first epicycloidal disc 50 is sleeved on the corresponding eccentric cylinder of the eccentric element 21 through the first shaft hole 503, since the eccentric cylinder is eccentrically disposed on the rotating shaft 20, the distance between the center a of the first epicycloidal disc hole 502 and the axis b of the rotating shaft 20 of the eccentric element 21 is the eccentric amount of the eccentric element 21 relative to the axis b of the rotating shaft 20, i.e., the eccentric amount e of the eccentric cylinder relative to the axis b of the rotating shaft 20, and in fig. 2F, the center a of the first epicycloidal disc hole 502 is exemplified as being eccentric upward relative to the axis b of the rotating shaft 20 of the eccentric element 21. Since the diameter of the first epicycloidal disc hole 502 is larger than the diameter of the connecting member 52, the diameter of the first hypocycloidal disc hole 512 is substantially equal to the diameter of the connecting member 52, and the eccentric directions of the first epicycloidal disc 50 and the first hypocycloidal disc 51 are opposite, when the connecting member 52 is attached to the inner wall surface of the first epicycloidal disc hole 502 and rotates, the distance between the center c of the connecting member 52 and the axis b of the rotating shaft 20 of the eccentric assembly 21 is also the eccentric amount e, and the radius of the connecting member 52 is assumed to be R, as can be seen from fig. 2F, the radius R of the first epicycloidal disc hole 502 is substantially twice the radius R of the connecting member 52 plus the eccentric amount e of the eccentric cylinder, that is, R +2e, the diameter of the first epicycloidal disc hole 502 is substantially equal to four times the diameter of the connecting member 52 plus the eccentric amount e, but the dimensional fit is slightly deviated due to the factors such as interference fit or clearance fit when actually manufactured, the diameter of the first epicycloidal disc hole 502 can cover the tolerance error. In addition, since the diameter of the first epicycloidal disc hole 502 is equal to the diameter of the second epicycloidal disc hole 612, the diameter of the second epicycloidal disc hole 612 is substantially equal to the diameter of the connecting member 52 plus four times the eccentric amount e, which will not be described herein again.

The first inner cycloid disc 51 and the second inner cycloid disc 60 operate in synchronization and in the same direction, and the first outer cycloid disc 50 and the second outer cycloid disc 61 operate in synchronization and in the same direction. As shown in fig. 2A, the connector 52 is formed of a cylindrical shape, and the first epicycloidal disk hole 502, the first hypocycloidal disk hole 512, the second hypocycloidal disk hole 602, and the second epicycloidal disk hole 612 are circular.

The second inner cycloid disc 60 contains a third shaft aperture 603 and the second outer cycloid disc 61 contains a fourth shaft aperture 613. The third shaft hole 603 and the fourth shaft hole 613 are respectively disposed at the geometric centers of the second inner cycloid disc 60 and the second outer cycloid disc 61, and a portion of the eccentric element 21 is rotatably disposed in the third shaft hole 603 and the fourth shaft hole 613, so that when the eccentric element 21 rotates, the second inner cycloid disc 60 and the second outer cycloid disc 61 are driven by the eccentric element 21 to rotate.

In the above embodiment, the first outer convex tooth portion 501 of the first outer cycloid disc 50 and the second outer convex tooth portion 511 of the first inner cycloid disc 51 of the first turntable group 5 can be mutually matched with the first roller 31 to form a first-order cycloid structure, and the third outer convex tooth portion 601 of the second inner cycloid disc 60 and the fourth outer convex tooth portion 611 of the second outer cycloid disc hole 612 of the second turntable group 6 can be mutually matched with the second roller 41 to form a second-order cycloid structure, so that the cycloid speed reducer 1 is a second-order reduction ratio cycloid speed reducer.

As can be seen from the above, since the cycloidal reducer 1 of the present invention comprises two sets of rotating disc groups, i.e. the first rotating disc group 5 and the second rotating disc group 6, and the first rotating disc group 5 comprises two cycloidal discs, namely a first epicycloidal disc 50 and a first hypocycloidal disc 51, while the second set 6 of discs likewise comprises two epicycloidal discs, namely, the second inner cycloid discs 60 and the second outer cycloid discs 61, the cycloid speed reducer 1 of the present invention actually uses four cycloid discs to contact the first rollers 31 of the first roller pulley set 3 and the second rollers 41 of the second roller pulley set 4, so that the load applied to each cycloid disc of the cycloid speed reducer 1 of the present invention can be reduced compared to a conventional cycloid speed reducer using only two cycloid discs to contact the rollers, therefore, the cycloidal reducer 1 has strong structural strength and high rigidity, and can be applied to occasions needing to bear high load. In addition, the eccentric assembly 21 of the eccentric device 2 of the cycloidal speed reducer 1 of the invention comprises a plurality of eccentric cylinders eccentrically arranged on the rotating shaft 20, each eccentric cylinder is arranged in the shaft hole of the corresponding cycloidal disc, and the eccentric directions of two cycloidal discs in four cycloidal discs are opposite to the eccentric directions of the other two cycloidal discs by the plurality of eccentric cylinders, so that the cycloidal speed reducer 1 of the invention can achieve dynamic balance without extra cost and cost for arranging a weight compensation device. Furthermore, since the cycloidal reducer 1 of the present invention directly uses the connecting member 52 to pass through the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second hypocycloidal disc hole 602, and the second epicycloidal disc hole 612, the first epicycloidal disc 50, the first hypocycloidal disc 51, the second hypocycloidal disc 60, and the second epicycloidal disc 61 can be assembled, the assembly of the cycloidal reducer 1 is simple, and the time and labor for assembly can be saved. In addition, in the same turntable set, because the diameter of one of the cycloid disc holes is larger than that of the connecting piece 52, and the diameter of the other cycloid disc hole is substantially equal to that of the connecting piece 52, the two cycloid discs of the same turntable set can maintain opposite eccentric directions and avoid mutual interference.

Please refer to fig. 2E in conjunction with fig. 2A and 2D, wherein fig. 2E is a schematic structural diagram of the eccentric device and a bearing set shown in fig. 2A. In some embodiments, the eccentric assembly 21 can be rotatably disposed in the first shaft hole 503, the second shaft hole 513, the third shaft hole 603 and the fourth shaft hole 613 through the bearing set 8, wherein the bearing set 8 can be, but is not limited to, three independent fourth bearings 80 a. In addition, the number of the eccentric cylinders of the eccentric assembly 21 may be, for example, three, that is, a first eccentric cylinder 22a, a second eccentric cylinder 23a and a third eccentric cylinder 24a which are adjacent to each other in sequence as shown in fig. 2E, and three fourth bearings 80a are respectively sleeved on the first eccentric cylinder 22a, the second eccentric cylinder 23a and the third eccentric cylinder 24a, so that the first shaft hole 503 of the first epicycloidal disc 50 is provided for the first eccentric cylinder 22a through the corresponding fourth bearing 80a, the second shaft hole 513 of the first epicycloidal disc 51 and the third shaft hole 603 of the second epicycloidal disc 60 are provided for the second eccentric cylinder 23a through the corresponding fourth bearing 80a, the fourth shaft hole 613 of the second epicycloidal disc 61 is provided for the third eccentric cylinder 24a through the corresponding fourth bearing 80a, so that the first epicycloidal disc 50 and the second epicycloidal disc 61 are respectively sleeved on the first eccentric cylinder 22a and the third eccentric cylinder 24a, the first inner cycloid disc 51 and the second inner cycloid disc 60 are sleeved on the second eccentric cylinder 23 a. The eccentric amounts of the first eccentric cylinder 22a, the second eccentric cylinder 23a and the third eccentric cylinder 24a are all the same, and the eccentric phases of the first eccentric cylinder 22a and the third eccentric cylinder 24a are the same, that is, the eccentric directions of the first eccentric cylinder 22a and the third eccentric cylinder 24a are the same, and further, the eccentric phase of the second eccentric cylinder 23a is different from the eccentric phases of the first eccentric cylinder 22a and the third eccentric cylinder 24a by 180 degrees, that is, the eccentric direction of the second eccentric cylinder 23a is opposite to the eccentric directions of the first eccentric cylinder 22a and the third eccentric cylinder 24 a. In this way, the eccentric directions of the first hypocycloidal disc 51 and the second hypocycloidal disc 60 are opposite to the eccentric directions of the first epicycloidal disc 50 and the second epicycloidal disc 61, so that the cycloidal reducer 1 of the present invention can compensate for dynamic balance without additionally providing an unbalance compensation device.

In some embodiments, since the first outer teeth 501 of the first outer cycloid discs 50 and the second outer teeth 511 of the first inner cycloid discs 51 all need to contact the first rollers 31, and the third outer teeth 601 of the second inner cycloid discs 60 and the fourth outer teeth 611 of the second outer cycloid discs 61 all need to contact the second rollers 41, the number of teeth and the shape of the teeth of the first outer teeth 501 of the first outer cycloid discs 50 are substantially the same as the number of teeth and the shape of the teeth of the second outer teeth 511 of the first inner cycloid discs 51, and the number of teeth and the shape of the teeth of the third outer teeth 601 of the second inner cycloid discs 60 and the shape of the teeth of the fourth outer teeth 611 of the second outer cycloid discs 61 are substantially the same as the shape of the teeth. The number of the first rollers 31 is at least one greater than the number of the first outer teeth 501 of the first epicycloidal disc 50 and the number of the second outer teeth 511 of the first inner cycloidal disc 51, and the number of the second rollers 41 is at least one greater than the number of the third outer teeth 601 of the second hypocycloidal disc 60 and the number of the fourth outer teeth 611 of the second epicycloidal disc 61.

The operation of the cycloidal reducer 1 of the present embodiment will be exemplarily described below. When the rotating shaft 20 receives power input from a motor (not shown) and rotates counterclockwise, the first eccentric cylinder 22a, the second eccentric cylinder 23a and the third eccentric cylinder 24a are driven by the rotating shaft 20 to rotate eccentrically, the deflection motion of the first eccentric cylinder 22a and the deflection motion of the third eccentric cylinder 24a become a pushing force to push the first epicycloidal disk 50 and the second epicycloidal disk 61 to rotate slowly clockwise, and the deflection motion of the second eccentric cylinder 23a become a pushing force to push the first epicycloidal disk 51 and the second epicycloidal disk 60. Furthermore, since the first roller pulley set 3 does not rotate around the axis of the rotating shaft 20, the third outer teeth 601 of the second inner cycloid discs 60 and the fourth outer teeth 611 of the second outer cycloid discs 61 perform a pushing motion with the plurality of second rollers 41 of the second roller pulley set 4, and further the plurality of second rollers 41 rotate counterclockwise around the axis of the rotating shaft 20, so that the motion of the plurality of second rollers 41 drives the second pulley 40 to rotate counterclockwise, and the second roller pulley set 4 actually rotates counterclockwise. In this embodiment, the second disk 40 of the rotating second roller-disk group 4 generates a power output.

Please refer to fig. 3A and fig. 3B. Fig. 3A is a schematic view of a combined structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal speed reducer according to a second preferred embodiment of the present invention, and fig. 3B is a schematic view of an exemplary cross-sectional structure of the cycloidal speed reducer according to the second preferred embodiment of the present invention, wherein structures similar to those in fig. 2C and 2D are denoted by the same reference numerals, and therefore, no further description is provided herein. However, compared to the cycloidal reducer 1 according to the first preferred embodiment of the present invention, although the cycloidal reducer 1a according to the second preferred embodiment of the present invention is also a cycloidal reducer with a second-order reduction ratio, the diameters of the first epicycloidal disc hole 502 and the second epicycloidal disc hole 612 are substantially equal to the diameter of the connecting member 52, and the diameters of the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602 are equal to each other and larger than the diameter of the connecting member 52. Therefore, when the connecting member 52 passes through the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602 and second epicycloidal disc hole 612, the first epicycloidal disc 50 and the second epicycloidal disc 61 can be assembled by the connecting member 52, and the connecting member 52 only contacts with part of the wall surface of the corresponding first hypocycloidal disc hole 512 and second hypocycloidal disc hole 602. In some embodiments, the diameters of the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602 are substantially equal to the diameter of the connecting member 52 plus four times the eccentricity of the eccentric element 21 relative to the axis of the rotating shaft 20 (including tolerance errors), but not limited thereto.

Please refer to fig. 4A and 4B. Fig. 4A is a schematic cross-sectional view illustrating an exemplary cross-sectional structure of a cycloidal speed reducer according to a third preferred embodiment of the present invention, and fig. 4B is a schematic cross-sectional view illustrating a connecting member of the cycloidal speed reducer according to the third preferred embodiment of the present invention, wherein structures similar to those in fig. 3A and 3B are denoted by the same reference numerals, and thus, the description thereof is omitted. However, compared to the cycloidal reducer 1a according to the second preferred embodiment of the present invention, although the cycloidal reducer 1b according to the third preferred embodiment of the present invention is also a cycloidal reducer with a second-order reduction ratio, the connecting member 52 is inserted into the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second epicycloidal disc hole 612 and the second hypocycloidal disc hole 602, and the connecting piece 52 is closely attached to the wall surfaces of the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second epicycloidal disc hole 612 and the second hypocycloidal disc hole 602, wherein the diameter of the first hypocycloidal disk aperture 512 is equal to the diameter of the second hypocycloidal disk aperture 602, the diameter of the first epicycloidal disk aperture 502 is equal to the diameter of the second epicycloidal disk aperture 612, and the diameters of the first and second hypocycloidal disk apertures 512, 602 are larger than the diameters of the first and second epicycloidal disk apertures 502, 612. The connecting member 52 includes a first through-hole 521, a second through-hole 522 and a third through-hole 523, which are sequentially connected and integrally formed, the first through-hole 521 and the third through-hole 523 are respectively inserted into the first epicycloidal disc hole 502 and the second epicycloidal disc hole 612, the second through portion 522 is disposed through the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602, and the diameter of the first through portion 521 is equal to the diameter of the third through portion 523, the diameter of the second penetration portion 522 is larger than the diameter of the first penetration portion 521 and the diameter of the third penetration portion 523, and in addition, as shown in fig. 4B, there is an offset between the axial center of the second penetration portion 522 and the axial centers of the first penetration portion 521 and the third penetration portion 523, and the eccentric amount between the axis of the second penetrating portion 522 and the axes of the first penetrating portion 521 and the third penetrating portion 523 is preferably equal to twice the eccentric amount between two adjacent eccentric cylinders of the eccentric assembly 21. In the preferred embodiment, the diameter of the first epicycloidal disc hole 502 is substantially equal to the diameter of the first through-hole 521, the diameters of the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602 are substantially equal to the diameter of the second through-hole 522, and the diameter of the second epicycloidal disc hole 612 is substantially equal to the diameter of the third through-hole 523. Therefore, when the connecting element 52 is inserted into the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602, and second epicycloidal disc hole 612, the first insertion portion 521 of the connecting element 52 is fixedly connected to the first epicycloidal disc 50 and fills the first epicycloidal disc hole 502, the second insertion portion 522 of the connecting element 52 is fixedly connected to the first hypocycloidal disc 51 and the second hypocycloidal disc 60 and fills the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602, and the third insertion portion 523 of the connecting element 52 is fixedly connected to the second epicycloidal disc 61 and fills the second epicycloidal disc hole 612. Thereby, the first outer cycloid discs 50, the first inner cycloid discs 51, the second inner cycloid discs 60 and the second outer cycloid discs 61 can be phase-connected by the connecting members 52. In the third preferred embodiment of the present invention, since the diameters of the first hypocycloidal disc hole 512 and the second hypocycloidal disc hole 602 are substantially equal to the diameter of the second penetration portion 522, the diameter of the first epicycloidal disc hole 502 is substantially equal to the diameter of the first penetration portion 521, and the diameter of the second epicycloidal disc hole 612 is substantially equal to the diameter of the third penetration portion 523, when the connecting member 52 is inserted into the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second hypocycloidal disc hole 602, and the second epicycloidal disc hole 612, the connecting member 52 can respectively abut against the wall surfaces of the first epicycloidal disc hole 502, the first hypocycloidal disc hole 512, the second hypocycloidal disc hole 602, and the second epicycloidal disc hole 612, so that the structural strength and rigidity of the cycloidal reducer 1b can be further enhanced, and the application occasion of high load bearing is further facilitated. In addition, since the eccentric amount between the axis of the second penetrating portion 522 and the axes of the first penetrating portion 521 and the third penetrating portion 523 is twice as large as the eccentric amount between two adjacent eccentric cylinders of the eccentric assembly 21, the two cycloid discs of the same turntable set can maintain opposite eccentric directions and avoid mutual interference.

Please refer to fig. 5A, 5B and 5C. Fig. 5A is a schematic view of a combined structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal speed reducer according to a fourth preferred embodiment of the present invention, fig. 5B is a schematic view of an exemplary cross-sectional structure of the cycloidal speed reducer according to the fourth preferred embodiment of the present invention, fig. 5C is a schematic view of a structure of an eccentric device and a bearing set of the cycloidal speed reducer according to the fourth preferred embodiment of the present invention, wherein structures similar to those in fig. 2C and 2D are denoted by the same reference numerals, and therefore, no further description is provided herein. However, compared to the cycloidal reducer 1 according to the first preferred embodiment of the present invention, although the cycloidal reducer 1c according to the fourth preferred embodiment of the present invention is also a cycloidal reducer with a second-order reduction ratio, the diameters of the first hypocycloid disc hole 512 and the second hypocycloid disc hole 612 are substantially equal to the diameter of the connecting member 52, and the diameters of the first hypocycloid disc hole 502 and the second hypocycloid disc hole 602 are equal to each other and larger than the diameter of the connecting member 52. Therefore, when the connecting member 52 passes through the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602 and second epicycloidal disc hole 612, the first epicycloidal disc 51 and the second epicycloidal disc 61 can be assembled by the connecting member 52, and the connecting member 52 only contacts with part of the wall surface of the corresponding first epicycloidal disc hole 502 and second epicycloidal disc hole 602. In some embodiments, the diameter of the first epicycloidal disc hole 502 and the diameter of the second hypocycloidal disc hole 602 are substantially equal to the diameter of the connecting member 52 plus four times the eccentricity of the eccentric element 21 with respect to the axis of the rotating shaft 20 (including tolerance errors), but not limited thereto.

In addition, in the fourth preferred embodiment of the present invention, the bearing set 8 is instead composed of four independent fourth bearings 80b, but not limited thereto, and the number of the eccentric cylinders of the eccentric assembly 21 may be four, for example, as shown in fig. 5C, a first eccentric cylinder 22b, a second eccentric cylinder 23b, a third eccentric cylinder 24b and a fourth eccentric cylinder 25 which are adjacent in sequence, the four fourth bearings 80b are respectively sleeved on the first eccentric cylinder 22b, the second eccentric cylinder 23b, the third eccentric cylinder 24b and the fourth eccentric cylinder 25, so that the first shaft hole 503 of the first epicycloidal disc 50 is provided for the first eccentric cylinder 22b through the corresponding fourth bearing 80b, the second shaft hole 513 of the first epicycloidal disc 51 is provided for the second eccentric cylinder 23b through the corresponding fourth bearing 80b, the third shaft hole 603 of the second epicycloidal disc 60 is provided for the third eccentric cylinder 24b through the corresponding fourth bearing 80b, the fourth shaft hole 613 of the second outer cycloid discs 61 is provided for the fourth eccentric cylinder 25 to be disposed through the corresponding fourth bearing 80b, and therefore, the first outer cycloid disc 50, the first inner cycloid disc 51, the second inner cycloid disc 60 and the second outer cycloid disc 61 are respectively sleeved on the first eccentric cylinder 22b, the second eccentric cylinder 23b, the third eccentric cylinder 24b and the fourth eccentric cylinder 25. The eccentric amounts of the first eccentric cylinder 22b, the second eccentric cylinder 23b, the third eccentric cylinder 24b and the fourth eccentric cylinder 25 are all the same, and the eccentric phases of the first eccentric cylinder 22b and the third eccentric cylinder 24b are the same, that is, the eccentric directions of the first eccentric cylinder 22b and the third eccentric cylinder 24b are the same, and the eccentric phases of the second eccentric cylinder 23b and the fourth eccentric cylinder 25 are the same, that is, the eccentric directions of the second eccentric cylinder 23b and the fourth eccentric cylinder 25 are the same. Further, the eccentric phases of the second eccentric cylinder 23b and the fourth eccentric cylinder 25 are different from the eccentric phases of the first eccentric cylinder 22b and the third eccentric cylinder 24b by 180 degrees, that is, the eccentric directions of the second eccentric cylinder 23b and the fourth eccentric cylinder 25 are opposite to the eccentric directions of the first eccentric cylinder 22b and the third eccentric cylinder 24 b. In this way, the eccentric directions of the first inner cycloid disc 51 and the second outer cycloid disc 61 are opposite to the eccentric directions of the first outer cycloid disc 50 and the second inner cycloid disc 60, so that the cycloid speed reducer 1c can compensate for dynamic balance without additionally providing an unbalance compensation device.

Please refer to fig. 6A and 6B. Fig. 6A is a schematic view of a combined structure of an eccentric device, a first rotating disc set and a second rotating disc set of a cycloidal speed reducer according to a fifth preferred embodiment of the invention, and fig. 6B is a schematic view of an exemplary cross-sectional structure of the cycloidal speed reducer according to the fifth preferred embodiment of the invention, wherein structures similar to those in fig. 5A and 5B are denoted by the same reference numerals, and therefore, no further description is provided herein. However, compared to the cycloidal reducer 1c according to the fourth preferred embodiment of the present invention, although the cycloidal reducer 1d according to the fifth preferred embodiment of the present invention is also a cycloidal reducer with a second-order reduction ratio, the diameters of the first epicycloidal disc hole 502 and the second hypocycloidal disc hole 602 are substantially equal to the diameter of the connecting member 52, and the diameters of the first hypocycloidal disc hole 512 and the second epicycloidal disc hole 612 are equal to each other and larger than the diameter of the connecting member 52. Therefore, when the connecting member 52 passes through the corresponding first epicycloidal disc hole 502, first hypocycloidal disc hole 512, second hypocycloidal disc hole 602 and second epicycloidal disc hole 612, the first epicycloidal disc 50 and the second hypocycloidal disc 60 can be assembled by the connecting member 52, and the connecting member 52 only contacts with part of the wall surface of the corresponding first hypocycloidal disc hole 512 and second epicycloidal disc hole 612. In some embodiments, the diameters of the first hypocycloidal disc hole 512 and the second epicycloidal disc hole 612 are substantially equal to the diameter of the connecting member 52 plus four times the eccentricity of the eccentric element 21 relative to the axis of the rotating shaft 20 (to cover the error caused by the tolerance), but not limited thereto.

In summary, the present invention provides a cycloid speed reducer, which comprises two sets of turntable sets, and each turntable set comprises two cycloid discs, so that the cycloid speed reducer of the present invention can utilize four cycloid discs to contact with corresponding rollers, so that the load borne by each cycloid disc can be reduced. In addition, the eccentric assembly of the eccentric device of the cycloidal speed reducer further comprises a plurality of eccentric cylinders which are eccentrically arranged on the rotating shaft, each eccentric cylinder is arranged in the shaft hole of the corresponding cycloidal disc, and the eccentric directions of two cycloidal discs in the four cycloidal discs are opposite to the eccentric directions of the other two cycloidal discs by the plurality of eccentric cylinders, so that the cycloidal speed reducer can achieve dynamic balance without additionally spending cost and setting a weight compensation device. In addition, the cycloidal speed reducer directly utilizes the connecting piece to penetrate through the first epicycloidal disc hole, the first hypocycloidal disc hole, the second hypocycloidal disc hole and the second epicycloidal disc hole, so that the first epicycloidal disc, the first hypocycloidal disc, the second hypocycloidal disc and the second epicycloidal disc can be assembled, the cycloidal speed reducer is easy to assemble, and the assembling time and labor can be saved.