WO2021033819A1

WO2021033819A1 - Cycloidal reducer equipped with lubricating device

Info

Publication number: WO2021033819A1
Application number: PCT/KR2019/010981
Authority: WO
Inventors: 김광민; 신동혁; 염규덕
Original assignee: 우림기계 주식회사
Priority date: 2019-08-22
Filing date: 2019-08-28
Publication date: 2021-02-25
Also published as: KR102214172B1; CN112703336A

Abstract

The present invention is intended to smoothly supply a lubricant around a case pin in a cycloidal reducer. According to the present invention, lubricant storage grooves (43) are formed in the vertical direction on the inner surfaces of pin grooves (42A) that are continuously formed on the inner surface of a ring gear housing (10). A preload adjustment ring (50) is screwed into a shaft through hole (18A) of a hold flange (18) through which a crankshaft (28) of the cycloidal reducer passes, and moves up and down by rotation, wherein the preload adjustment ring (50) is configured such that the preload with an inner ring (76) can be accurately adjusted by pressing an outer ring (72) of an upper taper bearing (Bu), the inner ring (76) and the outer ring (72) having a roller (74) interposed therebetween.

Description

Cycloidal gear reducer with lubricating device

The present invention relates to a cycloidal reducer, and more particularly, a casing pin disposed inside a pair of rotating disks is configured to sufficiently supply lubricating oil so that it can rotate more smoothly inside the ring gear housing. It relates to a cycloidal reducer.

Various types of reducers, such as planetary gear reducers and cycloidal type reducers, are used in various fields as the reducers used to reduce the rotational speed to a desired level. Here, since the cycloid type reducer can obtain a high reduction ratio compared to its compact size, it is widely used in industrial robots, machine tools, and yaw pitch systems of wind power generators, and it can be said that the demand is increasing.

The basic structure of such a cycloidal reducer is actually widely known, but the configuration will be briefly described with reference to FIG. 1. The housing of a conventional cyclo-type speed reducer is composed of a ring gear housing 10 and a first end housing 12 and a second end housing 14 fixed to both ends of the ring gear housing 10. The input shaft 22 installed on one side of the

housing

10, 12, 14 transmits rotational power to the three shaft drive gears 26 through the pinion gear 24 connected to the lower end thereof.

In addition, the crankshaft 28 is coupled to interlock at the center of the shaft driving gear 26, and two

eccentric portions

28a and 28b are formed in the lower portion of the crankshaft 28 at regular intervals. A first disk 30 and a second disk 32 are installed vertically on the outside of each of the

eccentric portions

28a and 28b with

needle roller bearings

30 and 32 interposed therebetween. The above-described pair of

disks

30 and 32 are installed in a portion corresponding to the inside of the ring gear housing 10, and between the pair of

disks

30 and 32 and the ring gear housing 10 A number of case pins 36 are installed.

That is, the eccentric portions 28a positioned at the top of the three crankshafts 28 are mounted in the three mounting holes molded in the first disk 30, and the three eccentric portions 28a positioned at the bottom. It is installed in each of the three mounting holes molded in the second disk (32). In accordance with the rotation of the

eccentric portions

28a and 28b, the first disk 30 and the second disk 32 rotate eccentrically in the ring gear housing 10, and the first disk 30 and the second disk The rotation of 32 actually has a constant phase difference, so that the upper and

lower disks

30 and 32 alternately come into contact with the ring gear housing 10.

Here, the case pins 36, which are respectively disposed between the

disks

30 and 32 and the ring gear housing 10, are arranged to be upright based on FIG. 1, for example, by the second end housing 14 It has a fixed height by being supported. Further, a plurality of

pin grooves

30A and 32A are continuously formed on the outer surfaces of each of the

disks

30 and 32, and a plurality of pin grooves 42A are continuously formed on the inner surface of the ring gear housing 10 as well. Therefore, the case pin 36 can be said to be interposed between the

pin grooves

30A and 32A on the outer surface of the disk and the pin groove 42A on the inner surface of the ring gear housing 10.

The principle of operation of such a cycloid speed reducer is known and will be briefly examined. The rotational force of the input shaft 22 described above is transmitted to the three shaft drive gears 26 through the pinion gear 24. Each of the three shaft drive gears 26 rotates the crankshaft 28, and the rotation of the shaft 28 is performed by the first disk 30 and the second disk 32 through respective

eccentric portions

28a and 28b. ).

Here,

pin grooves

30A and 32A are formed on the outer sides of the first disk 30 and the second disk 32 while having a predetermined phase difference (angular difference), and when the crankshaft 28 rotates, the The first disk 30 and the second disk 32 partially rotate eccentrically by contacting the inner side of the ring gear housing 10 by the three

eccentric portions

28a and 28b. Here, the first disk 30 and the second disk 32 rotate with a constant phase difference (angle difference).

Here, the eccentric rotation of the first disk 30 and the second disk 32 is arranged between the pin grooves 42A of the fixed ring gear housing 10 and rotates only at the fixed position. Thus, the three crankshafts 28 rotate and rotate at the same time. According to the revolution of the crankshaft 28, the

disks

30 and 32 also rotate as a whole. Here, since the ring gear housing 10 has a pin groove 42A formed on its inner surface and maintains a fixed state, it can be said that it has a function similar to that of a ring gear in a planetary gear reducer.

Here, the pin grooves 30A of the first disk 30 and the pin grooves 32A of the second disk 32 have a phase difference, which is the disk 30 so that the pin grooves 30A and the pin grooves 32A are alternately positioned with each other. Means that ,32) is placed. For reference, the crankshaft 28 is assembled while passing through each of the

discs

30 and 32, and

needle roller bearings

29a and 29b are interposed therebetween.

In addition, since the crankshaft 28 also penetrates the hold flange 18, the hold flange 18 also rotates. Here, the holding flange 18 is rotatably supported on the inner surface of the ring gear housing 10 by an angular ball bearing (B). In addition, the upper and lower ends of the crankshaft 28 are rotatably supported by a plurality of tapered bearings BTa and BTb, respectively.

In addition, since the hold flange 18 is connected to the output shaft 40, the rotation of the hold flange 18 can be said to be substantially equivalent to the rotation of the reduced output shaft 40. In addition, the substantially reduced output rotation speed is the rotation of the output shaft 40 described above, and this rotation is equivalent to the rotation of the crankshaft 28 and the rotation of the hold flange 18 and the

disks

30 and 32. have.

Here, in order to support the rotation of the crankshaft 28, tapered bearings BTa and BTb, which are generally composed of inner and outer rings, and rollers therebetween, support the upper and lower portions of the crankshaft 28. The lower end of the lower tapered bearing BTb is supported while being hooked on the locking protrusion 42 of the output shaft 40, for example, and the upper end of the upper tapered bearing BTa is interposed with the tapered bearing shim 44. It is supported by the stop ring 46 in the state. Here, the stopping ring 46 is molded into the holding flange 18, and is fitted and fixed to the inner periphery of the shaft through hole 18A into which the crankshaft 28 is inserted.

In the cycloid speed reducer having such a configuration, a plurality of case pins disposed to surround the entire outer circumference of the disk, a plurality of pin grooves 42A molded in the vertical direction inside the ring gear housing 10, and each disk ( Rotation is performed between a plurality of

pin grooves

30A and 32A on the outer surfaces of the 30 and 32). In addition, since the actual case pin and the disk rotating around it move in close contact, there is not enough space to supply the lubricant.

The main object of the present invention is to enable sufficient supply of lubricating oil around a case pin in a cycloid type reducer.

Another object of the present invention is to provide a device capable of easily setting a preload of a tapered bearing supporting a crankshaft.

The crankshaft of the cycloid reducer of the device of the present invention rotates by an input shaft, and consists of three pieces in which a first eccentric portion and a second eccentric portion are formed vertically, respectively, and they are installed in a state passing through the holding flange. . The upper and lower portions of the crankshaft are supported by upper and lower tapered bearings.

In addition, the first disk has three mounting holes through which the first eccentric portion of the crankshaft is installed, and the pin groove in the vertical direction is continuously formed on the outer surface, and the second disk has three mounting holes in which the second eccentric portion is respectively installed. Mounting holes are provided, and pin grooves in the vertical direction are continuously molded on the outer surface. In addition, the ring gear housing is provided on the outer side of the first disk and the second disk, and has a continuously formed pin groove on the inner surface to support the case pin rotating between the pin groove of the disk. Here, according to the present invention, the oil storage groove is formed in the vertical direction in the pin groove of the ring gear housing, so that the lubricant can be stored around the case pin.

According to another embodiment of the present invention, it is configured to further include a device for adjusting the preload of the upper and lower tapered bearings. In such a preload control device, a preload control ring, which is screwed into a shaft through hole of a hold flange through which the crankshaft passes, and moves up and down by rotation, presses the outer ring of the upper tapered bearing to prevent preload with the inner ring through the roller. It is configured to be adjustable.

According to a more specific embodiment, a part of the preload control ring is divided into an upper part of the control ring and a lower part of the control ring by a horizontal slit, and a bolt screwed to the adjustment screw hole 58 formed on the upper part of the control ring By pressing, one side of the threaded portion of the outer surface of the preload control ring is in close contact with one side of the threaded portion of the inner surface of the shaft through hole to prevent it from being arbitrarily released.

According to the configuration of the present invention as described above, since lubricating oil is always stored in the oil storage groove formed inside the pin groove of the ring gear housing having the function of the ring gear, smoother rotation when contacted by rotation of the case pin is achieved. It is expected to make it possible. Lubricating oil stored in such a storage groove will be able to be sufficiently supplied substantially around the case pin by contact with the case pin.

Here, the case pin repeats a motion that is separated from or close to the reservoir groove, and this motion is expected to be used as a lubricant by substantially storing lubricant or ejecting the stored lubricant to the outside. As described above, if the lubricant is sufficiently supplied according to the present invention, it is not only helpful for the relative rolling movement by smooth movement of the oil during the operation of the case pin and the disk, but also reduces the occurrence of noise and improves the overall reliability of operation. It is expected to be.

And by rotating the preload control ring in the present invention, it is possible to accurately adjust the preload between the inner ring and the outer ring by pressing the tapered bearing while moving downward. And in the control ring upper part and the control ring lower part divided by the horizontal slit of the present invention preload control ring, the lower end of the headless bolt inserted into the adjusting screw hole of the control ring upper part pushes the lower part of the control ring downward, so that the outer surface thread It can be in close contact with the thread on the inner side of the through hole. According to this configuration and action, it is possible to reliably prevent the preload control ring from being arbitrarily separated.

1 is an exemplary cross-sectional view of a conventional cycloidal reducer.

Figure 2 is an exemplary cross-sectional view of the present invention cycloidal reducer.

Figure 3 is a partial cut-away perspective view of the present invention cycloidal reducer.

Figure 4 is an exemplary cross-sectional view showing the relationship between the pin groove and the case pin of the present invention.

Figure 5 is an exemplary view of a preload control ring used in the present invention.

6 is an enlarged view of part A of FIG. 2.

Next, the present invention will be described in more detail through an embodiment shown in the drawings. In the following description, the same portions as those of the conventional configuration described above will be described while using the same reference numerals, and since configurations overlapping with the conventional are substantially known, detailed descriptions thereof will be omitted.

As shown in Figs. 2 and 3, the housing of the cycloidal reducer includes a ring gear housing 10, a first end housing 12 and a second end housing fixed to both ends of the ring gear housing 10. Consisting of (14) is as described above. The input shaft 22 installed on one side of the

housing

At the center of each shaft driving gear 26, the crankshaft 28 is coupled so as to be interlocked, and at the lower portion of the crankshaft 28, two

eccentric portions

28a, 28b are molded up and down at regular intervals. have. Each of the

eccentric portions

28a and 28b has

needle roller bearings

30 and 32 interposed therebetween, and a first disk 30 and a second disk 32 are installed vertically.

Here, the crankshaft 28 can be said to be for generating an output by rotating the

disks

30 and 32 in a cycloidal gear reducer. In addition, the crankshaft 28 extends downward through the hold flange 18, and the lower end of the crankshaft 28 penetrates the

disks

30 and 32.

Here, configurations of the

disks

30 and 32, the case pins 36, and the inner wall of the ring gear housing 10 will be described with reference to FIGS. 4 and 2. It can be seen that a plurality of pin grooves 42A are continuously formed on the entire inner surface of the ring gear housing 10. In addition, it can be seen that the

pin grooves

30A and 32A are continuously molded also on the inner surfaces of the pair of

disks

30 and 32 arranged up and down. For convenience of explanation, in FIG. 4, only one of a pair of disks is shown.

A plurality of case pins 36 are installed between the pin grooves 42A of the ring gear housing 10 and the

pin grooves

30A and 32A of the

disks

30 and 32. As described above, since the

disks

30 and 32 are partially rotated so as to be close to the inner surface of the ring gear housing 10, the center is As a reference, the case pin 36 at the lower end is completely inserted between the pin grooves 42A of the ring gear housing 10 and the

pin grooves

30A and 32A of the

disks

30 and 32, and the case pin 36 at the upper end It can be seen that the silver enters into the pin grooves 42A of the ring gear housing 10, but comes out of the

pin grooves

30A and 32A of the

disks

30 and 32 and contacts the peaks of the

pin grooves

30A and 32A.

Here, the ring gear housing 10 is held in a fixed state, and the

disks

30 and 32 rotate, so the case pin 36 that rolls while in contact with the

disks

30 and 32 is the

pin grooves

30A and 32A. It completely enters, and the lower end of FIG. 4(b) shows this state. And the casing pin 36 comes out from the

pin grooves

30A and 32A while rolling by contact with the disk, and the upper end of FIG. 4(b) shows this state.

And after coming out completely from the pin grooves (30A, 32A), the casing pin (36) that performs the rolling motion while in contact with the rotating disk (30, 32) is the next ring gear housing (10) corresponding to the rotation direction of the disk. It enters into the pin groove (42A) of. As the above process is repeated according to the rotation of the

disks

30 and 32, a decelerated output corresponding to the rotation of the disk and the revolution of the crankshaft is produced.

According to the present invention, the oil storage groove 43 is formed in the pin groove 42A of the ring gear housing 10 in the vertical direction. The oil storage groove 43 is molded for the entire top and bottom of the ring gear housing 10, and lubricating oil may be stored therein. As described above, the lubricant stored in the oil storage groove 43 of the ring gear housing 10 is moved away from the oil storage groove 43 while the case pin 36 rolls as described above. (36) It is also possible to supply or store around.

By the configuration of the oil storage groove 43, the supply of lubricating oil to the case pin 36 and the components having the pin groove around the case pin 36 can be sufficiently maintained. And by having a sufficient lubrication action as described above, it is possible to exhibit a sufficient function as a speed reducer, as well as an advantage such as a reduction in noise can be expected.

Here, the storage groove 43 described above may be formed at any position if it is inside the key groove 42A, but considering the rolling motion of the case pin 36 and movement to the adjacent pin groove as described above, the key groove 42A It is thought that it would be desirable to be molded up and down in the inner central part of the

Next, the support structure of the crankshaft 28 of the present invention will be described. The crankshaft 28 of the present invention is supported so as to be rotatable by tapered bearings (Bu, Bd) at the top and bottom. Here, the lower portion of the lower tapered bearing Bd supporting the lower portion of the crankshaft 28 is supported by the support jaws 42 formed on the upper portion of the output shaft 40, and the upper portion of the lower tapered bearing Bd is the crankshaft. It is supported by the spacer Sd supported by 28.

And the upper part of the upper tapered bearing (Bu) supporting the upper part of the crankshaft 28 is supported by the preload adjustment ring 50 supported by the hold flange 18, and the lower part of the upper tapered bearing (Bu) is the crankshaft. It is supported by the spacer Su supported by 28. Here, the preload adjusting ring 50 is for adjusting the preload of the upper and lower tapered bearings (Bu, Bd) for supporting the crankshaft 28. And the preload of the tapered bearings (Bu, Bd) is achieved by finely adjusting the upper and lower positions.

Since the above-described spacers Su and Sd are respectively hung on the jaws of the crankshaft 28, the spacers Su contacting the bottom surface of the upper tapered bearing Bu cannot independently move downward. In addition, the spacer Sd contacting the upper portion of the lower tapered bearing Bd cannot independently move upward.

Therefore, the position of the lower tapered bearing (Bd) is determined, and the preload of the tapered bearings (Bu, Bd) is determined depending on how downward the upper tapered bearing (Bu) is adjusted by the preload adjustment ring 50. I can. As shown in Fig. 4, the preload control ring 50 of the present invention includes an operation groove 52 formed on an inner circumferential surface and an outer threaded portion 54 formed on an outer circumferential surface.

The operation groove 52 is for rotating the preload control ring 50 using a tool, and the outer side thread 54 holds the preload control ring 50 in the shaft through hole 18A of the holding flange 18. It is for screwing inside. That is, the inner periphery of the shaft through-hole 18A is processed with a female thread, so that it is screwed with the outer surface threaded portion 54 of the preload adjusting ring 50. Here, that the preload control ring 50 is screwed into the shaft through hole 18A has the same meaning as that it can be moved finely up and down by rotation.

Therefore, as shown in FIG. 5, when the preload control ring 50 is rotated, the preload control ring 50 can be finely adjusted up and down. For example, when the preload control ring 50 moves downward, the outer ring 72 of the upper taper bearing Bu in contact with the bottom surface is pressed downward, and the inner ring 76 through the roller 74 The preload is adjusted between.

And at the same time, the inner ring 76 of the upper tapered bearing Bu finely presses the crankshaft 28 downward through the spacer Su by the force applied downward. The downward movement of the crankshaft 28 presses the inner ring 86 of the lower tapered bearing Bd downward through the spacer Sd at the bottom, so that the outer ring 82 with the roller 84 interposed therebetween. The preload is adjusted between and.

As described above, by rotating the preload control ring 50 through the operating groove 52 using, for example, a tool, the inner and outer rings in the upper taper bearing (Bu) and the lower tapered bearing (Bd) It can be seen that the preload between them can be adjusted. And since the speed reducer of the present invention repeats rotation, the preload adjustment ring 50 screwed into the mounting hole 18A of the hold flange 18 can be released by rotation.

In the present invention, the preload control ring 50 has a separate configuration so as not to loosen arbitrarily. 4 and 5, a part of the preload control ring 50, for example, about half, is divided by a horizontal slit 56, and an upper part of the control ring 50A is divided into the upper part, and the lower part thereof. In the lower portion of the adjustment ring (50B) is molded. And the adjusting screw hole 58 is molded in the adjusting ring upper part 50A corresponding to the upper part of the horizontal slit 56. To this adjustment screw hole 58, for example, a headless bolt 60 is screwed.

These tanning bolts 60 may move downward by rotation, and apply a force to the upper surface of the lower adjustment ring 50B. In this case, the lower portion of the adjustment ring 50B is elastically deformed downward, and at this time, one side of the screw thread of the outer surface screw portion 54 is pressed to one side of the thread formed inside the through hole 18A, and the force By this, the threads on both sides are in close contact with each other. Therefore, by the force that the tanning bolt 60 exerts on the lower portion of the adjustment ring 50B, one side of the screw portion 54 on the outer surface of the lower portion of the adjustment ring 50B and the threaded portion on the inner surface of the through hole 18A are in close contact with each other, resulting in frictional force. It works remarkably largely. In this case, it is thought that it will be possible to further prevent the preload control ring 50 from being released due to the rotation of the cycloidal reducer.

As described above, the present invention is configured so that the preload control ring 50 is screwed into the shaft through hole 18A of the hold flange 18, and the preload of the tapered bearing can be adjusted based on the vertical movement by rotation. It can be seen that this is a basic technical concept. In addition, it can be understood that some threads of the preload control ring 50 and the threads of the shaft through-hole 18A are in close contact with each other so that they are not loosened arbitrarily.

Claims

Three crankshafts 28 rotated by the input shaft and each having a first eccentric portion 28a and a second eccentric portion 28b formed vertically;

Upper and lower tapered bearings (Bu and Bd) respectively supporting upper and lower portions of the crankshaft;

A first disk (30) having three mounting holes into which the first eccentric portions (28a) are respectively installed, and in which pin grooves (30A) in the vertical direction are continuously formed on the outer surface;

A second disk (32) having three mounting holes to which the second eccentric portions (28b) are respectively installed, and in which pin grooves (32A) in the vertical direction are continuously formed on the outer surface; And

A pin groove (which is provided on the outside of the first disk 30 and the second disk 32) and continuously formed to support the case pin 36 that rotates between the pin groove 30A and the pin groove 32A. It is composed of a ring gear housing 10 having 42A) on the inner surface;

Cycloidal reducer, characterized in that the oil storage groove is formed in the vertical direction in the pin groove (42A) of the ring gear housing (10).
The method of claim 1,

The preload adjustment ring 50, which is screwed into the shaft through hole 18A of the hold flange 18 through which the crankshaft 28 passes, and moves up and down by rotation, connects the outer ring 72 of the upper taper bearing (Bu). A preload control device of a cycloid type speed reducer capable of adjusting the preload with the inner ring 76 interposed by the roller 74 by pressing.
The method according to claim 1 or 2,

A part of the preload adjustment ring 50 is divided into an adjustment ring upper part 50A and an adjustment ring lower part 50B by a horizontal slit 56, and in the adjustment screw hole 58 molded in the adjustment ring upper part 50A. The bolt to be screwed presses the lower part of the adjusting ring 50B, so that one side of the threaded part of the outer surface of the preload adjusting ring 50 is in close contact with one side of the threaded part of the inner surface of the shaft through hole 18A. Preload control device.