WO2012036033A1

WO2012036033A1 - Planetary gear device

Info

Publication number: WO2012036033A1
Application number: PCT/JP2011/070331
Authority: WO
Inventors: 酒井　俊行
Original assignee: アイシン精機株式会社
Priority date: 2010-09-16
Filing date: 2011-09-07
Publication date: 2012-03-22
Also published as: JP5429119B2; JP2012062974A

Abstract

A planetary gear device is provided with: a sun gear having a central axis; four planetary gears connected to and supported by two carriers at equal intervals in the circumferential direction; and an elastic ring for integrally connecting the support shaft of the four planetary gears in the circumferential direction with the sun gear in the center. The four planetary gears constitute two sets of two each. The two planetary gears in each set face one another with the sun gear therebetween, and each planetary gear is supported by means of the support shaft. The elastic ring applies, from the direction of an internal gear or the sun gear, elastic force to the support shaft of two planetary gears in a first set facing one another with the sun gear therebetween. Moreover, the elastic ring applies, from the direction in which the elastic ring did not apply elastic force to the support shaft of the first set of planetary gears, elastic force to the support shaft of two planetary gears in a second set facing one another with the sun gear therebetween.

Description

Planetary gear set

The present invention relates to a planetary gear device.

The planetary gear device is used in a wide range of fields because the input shaft and the output shaft can be arranged on the same coaxial line, a large reduction ratio can be obtained, and a large torque can be transmitted. By the way, a plurality of planetary gears have a structure that is disadvantageous to sound, such as taking a larger backlash from the accuracy limit of the gear teeth and shaft, etc. due to the structure that revolves while rotating by rotating with the sun gear and the internal gear. It has become. For this reason, various devices for suppressing the hitting sound have been proposed (for example, Patent Document 1).

In Patent Document 1, the internal gear is divided into two, the two divided gears are connected by a tension coil spring, and the two split gears are pulled together by the elastic force of the coil spring. The two split gears maintain the contact surface pressure of each tooth surface constant in meshing between the internal gear and the planetary gear and meshing between the planetary gear and the sun gear by the elastic force of the tension coil spring. I try to suppress the sound.

Japanese Patent Laid-Open No. 2003-247631

However, the hitting prevention structure of the planetary gear device has to divide each gear, which increases the number of parts and makes the structure more complicated, requiring much labor for assembly.

In addition, since the split gears are pulled with each other, the meshing between the internal gear and the planetary gear is sufficient to keep the contact surface pressure of each tooth surface constant, but between the planetary gear and the sun gear. In meshing, it was not sufficient to keep the contact surface pressure of each tooth surface constant.

In order to solve the above-described problems, an object of the present invention is to provide a planetary gear device that has a low number of parts, has a simpler structure, and is easy to assemble and excellent in silent performance.

In one aspect of the present invention, a planetary gear device includes a sun gear having a central axis, and four planetary gears connected and supported at equal intervals in the circumferential direction by two carriers. There are two planetary gears in one set, and the two planetary gears in each set face each other across the sun gear, and each planetary gear is supported by a support shaft, and four planetary gears and four The planetary gear support shafts are integrally connected in the circumferential direction around the sun gear, and the support shafts of the first planetary gears of the first set opposite to each other with the sun gear interposed therebetween are connected to the internal gear and the sun gear. The elastic force is applied in the direction of either the internal gear or the sun gear to the support shafts of the second planetary gears of the second set that are opposed to each other with the sun gear sandwiched between them. There is provided a planetary gear device provided with an elastic ring for imparting.

According to the above configuration, the elastic ring is configured such that the support shafts of the two planetary gears of the first set facing each other with the sun gear interposed therebetween are disposed on either the internal gear or the sun gear, and The support shafts of the second planetary gears of the second set facing each other with the gears interposed therebetween are each given elastic force to the other of the internal gear and the sun gear. Accordingly, the planetary gears facing each other across the sun gear are pressed against the internal teeth of the internal gear and the external teeth of the sun gear, respectively, without rattling, and a plurality of simultaneous meshing of the planetary gears due to backlash. Rotates quietly without any humming. As a result, the planetary gear device has an excellent silent performance with a small number of parts, a simple structure, and easy assembly.

In one embodiment, the elastic ring is an elliptical elastic ring having a major axis and a minor axis, and the elastic ring is on the major axis line across the intersection where the major axis and the minor axis intersect, and the diameter of the elastic ring A pair of first bearing holes at two positions at the center of the width in the direction and a pair of second bearings at the two positions on the short diameter line across the intersection and at the center of the radial width of the elastic ring A pair of first bearing holes, a first set of two planetary gear support shafts, and a pair of second bearing holes of a second set of two planetary gear support shafts, respectively. Connect with elastic deformation.

According to the above configuration, since the elastic ring attempts to restore an elliptical shape from the elastically deformed state, the support shaft of the planetary gear that is penetrated and supported by the first bearing hole of the elastic ring is elastic in the direction of the internal gear. A force is applied, and the support shaft of the planetary gear that is supported through the second bearing hole of the elastic ring is given an elastic force in the direction of the sun gear. The two planetary gears of the first set facing each other across the sun gear are pressed against the internal teeth of the internal gear without rattling, and the second planet gears facing each other across the sun gear The two planetary gears in the set are pressed against the external teeth of the sun gear without rattling.

In another embodiment, the elastic ring is a perfect circular elastic ring, and the elastic ring is on a first line passing through the central point of the elastic ring and at an equal first distance across the central point. A pair of first bearing holes at two positions of the elastic ring, and a second line that passes through the central point of the elastic ring and is on a second line orthogonal to the first line and is equal to the central point and shorter than the first distance. A pair of second bearing holes are provided at two positions of the elastic ring at a distance, and the support shafts of the first set of two planetary gears are provided in the pair of first bearing holes, and the second bearing holes are provided in the second pair. The support shafts of the two planetary gears in the set are connected by being elastically deformed.

According to the above configuration, since the elastic ring tries to restore the circular shape from the elastically deformed state, the support shaft of the planetary gear that is supported by the first bearing hole of the elastic ring is elastic in the direction of the internal gear. A force is applied, and the support shaft of the planetary gear that is supported through the second bearing hole of the elastic ring is given an elastic force in the direction of the sun gear. The two planetary gears of the first set facing each other across the sun gear are pressed against the internal teeth of the internal gear without rattling, and the second planet gears facing each other across the sun gear The two planetary gears in the set are pressed against the external teeth of the sun gear without rattling.

In another embodiment, each of the support shafts of the four planetary gears has a first shaft portion and a second shaft portion, and the two carriers are the first shafts of the support shafts of the four planetary gears. A first carrier that links and supports the second carrier, and a second carrier that links and supports the second shafts of the support shafts of the four planetary gears, and is opposite to the first carrier with respect to the planetary gear. The second shaft portions of the support shafts of the four planetary gears are connected to each other by being elastically deformed and arranged on the two carriers.

According to the above configuration, the support shaft of the planetary gear supported through the first bearing hole is given an elastic force in the direction of the internal gear with the first carrier as a fulcrum. Further, the support shaft of the planetary gear supported through the second bearing hole of the elastic ring is given an elastic force in the direction of the sun gear with the first carrier as a fulcrum.

In yet another embodiment, the elastic ring is composed of the two carriers that integrally connect the support shafts of the four planetary gears in the circumferential direction with the sun gear in the circumferential direction.

According to the above configuration, since the carrier tries to restore from the elastically deformed state to the original state, the support shaft of the planetary gear that is supported through the first bearing hole of the carrier has an elastic force in the direction of the internal gear. And the support shaft of the planetary gear, which is supported through the second bearing hole of the carrier, is given an elastic force in the direction of the sun gear. The two planetary gears of the first set facing each other across the sun gear are pressed against the internal teeth of the internal gear without rattling, and the second planet gears facing each other across the sun gear The two planetary gears in the set are pressed against the external teeth of the sun gear without rattling.

In another embodiment, the bearing hole formed in the first carrier has a circular cross section, and the bearing hole formed in the second carrier is a long hole in the radial direction centered on the central axis of the planetary gear device. is there.

In another embodiment, the narrow slot of the bearing slot formed in the second carrier matches the diameter of the support shaft, and the wide interval is longer than the diameter of the support shaft.

According to the above configuration, the second carrier can support the support shaft of each planetary gear so as to be rotatable within the bearing slot, and can bias the support shaft in the radial direction along the bearing slot.

In another embodiment, the shape of the bearing hole formed in the carrier penetrating and supporting the support shaft protruding from one side of the planetary gear is formed so that the inner diameter thereof is expanded toward the planetary gear.

According to the above configuration, when the shaft is rotated by the elastic ring with the bearing hole as a fulcrum, the shaft can be easily rotated.

In another embodiment, an internal gear, a sun gear, four planetary gears, and a carrier are arranged in a cylindrical gear case.

According to the above configuration,
In another embodiment, a sun gear, four planet gears, and a carrier are disposed in the internal gear.

1 is an overall perspective view of a planetary gear device according to a first embodiment. The disassembled perspective view of the planetary gear apparatus of 1st Embodiment. The front view which shows the state by which the planetary gear was attached to the 1st carrier of 1st Embodiment. The front view which shows the state by which the planetary gear was attached to the 2nd carrier of 1st Embodiment. The front view of the 2nd carrier of 1st Embodiment. Explanatory drawing for demonstrating the bearing long hole formed in the 2nd carrier of 1st Embodiment. The front view of the elastic ring in the state which is not applying the external force of 1st Embodiment. The front view of the elastic ring in the state which the alignment action of 1st Embodiment is working. The front view of the elastic ring in the state which is not applying the external force of 2nd Embodiment. The front view of the elastic ring in the state which the alignment action of 2nd Embodiment is working. The exploded perspective view of the planetary gear apparatus of 3rd Embodiment. The front view of the 1st career in the state where the external force of a 3rd embodiment is not applied. The front view of the 1st career in the state where the alignment operation of a 3rd embodiment is working. The front view of the 2nd carrier in the state where the external force of 3rd Embodiment is not applied. The front view of the 2nd carrier in the state where the alignment action of 3rd Embodiment is working. FIG. 6 is a main part cross-sectional view for explaining another example of the first carrier.

First Embodiment Hereinafter, a first embodiment of a planetary gear device of the present invention will be described with reference to the drawings.

1 and 2, a planetary gear device 1 includes an internal gear 10, a sun gear 20, four planetary gears 30, first and

second carriers

40 and 50, an elastic ring, in a cylindrical gear case 2. 60.
Internal gear 10
The internal gear 10 is made of synthetic resin, is formed in a cylindrical shape, and an internal tooth 11 is formed on the inner peripheral surface thereof. The internal gear 10 is disposed so that its outer peripheral surface is slidable with respect to the inner peripheral surface of the gear case 2 with respect to the synthetic resin gear case 2 formed in a cylindrical shape. The central axis of the internal gear 10 coincides with the gear case 2, i.e., the central axis C <b> 1 of the planetary gear device 1, and the internal gear 10 is accommodated in the gear case 2 so as to be rotatable about the central axis C <b> 1.
Sun gear 20
The sun gear 20 is a spur gear made of synthetic resin having outer teeth 21 formed on the outer peripheral surface, and is disposed at the center position of the internal gear 10. Specifically, the sun gear 20 is rotatably arranged such that the center axis of the rotation shaft 22 coincides with the center axis C1 of the planetary gear device 1.
Planetary gear 30
The four planetary gears 30 are synthetic resin spur gears having outer teeth 31 formed on the outer peripheral surface thereof, and are respectively disposed between the internal gear 10 and the sun gear 20. The outer teeth 31 of the planetary gears 30 mesh with the inner teeth 11 of the inner gear 10 and the outer teeth 21 of the sun gear 20.

The four planetary gears 30 are in a set of two, and the two planetary gears 30 of the set are arranged opposite to each other with the sun gear 20 in between (see FIGS. 3 and 4). Each of the two planetary gears 30 in the first set is disposed at an interval of 90 degrees with respect to the center axis of the sun gear 20 with respect to the two planetary gears 30 in the second set. Yes. That is, the straight line connecting the two planetary gears 30 in the first set is substantially perpendicular to the straight line connecting the two planetary gears 30 in the second set.

Each of the four planetary gears 30 has a metal shaft 33 penetrating at the center thereof, and is supported so as to be rotatable in the radial direction and immovable in the thrust direction with respect to the shaft 33. Therefore, the central axis of the shaft 33 coincides with the central axis of the planetary gear 30.

For the shaft 33 that penetrates and supports the planetary gear 30, the shaft portion protruding from the first side (first carrier 40 side) of the planetary gear 30 is referred to as a first shaft portion 33 a, and the second side (second carrier 50). The shaft portion protruding from the side) is referred to as a second shaft portion 33b.

When the two planetary gears 30 of the first set and the two planetary gears 30 of the second set are particularly distinguished and described, for convenience of explanation, the two planetary gears 30 of the first set are described. The code is expressed as “30A”, and the code of the second planetary gear 30 in the second set is expressed as “30B”.
First carrier 40
As shown in FIG. 3, the first shaft portion 33a of the shaft 33 protruding from the first side of each planetary gear 30 penetrates and supports the bearing holes 41 formed in the first carrier 40 made of an annular synthetic resin. Has been. Each bearing hole 41 formed in the first carrier 40 has a circular cross section, and rotatably supports the first shaft portion 33a. Therefore, the first carrier 40 supports each planetary gear 30 so as to be rotatable about the central axis of the first shaft portion 33a (the central axis of the planetary gear 30).

Moreover, the first carrier 40 holds the first shaft portions 33a (the planetary gears 30) of the shafts 33 at equal intervals of 90 ° in the circumferential direction around the central axis of the sun gear 20.
Second carrier 50
As shown in FIG. 4, the second shaft portion 33 b of the shaft 33 protruding from the second side of each planetary gear 30 passes through a bearing slot 51 formed in the second carrier 50 made of an annular synthetic resin. It is supported.

As shown in FIGS. 5 and 6, each bearing slot 51 formed in the second carrier 50 is a slot that is long in the radial direction centered on the central axis C <b> 1 of the planetary gear device 1, and has a width thereof. The narrow interval coincides with the diameter of the shaft 33, and the wide interval is longer than the diameter of the shaft 33.

Accordingly, the second carrier 50 supports the second shaft portion 33 b of the shaft 33 protruding from the second side of each planetary gear 30 so as to be rotatable in the bearing elongated hole 51, and also along the bearing elongated hole 51. The biaxial portion 33b can be biased in the radial direction. In addition, the second carrier 50 has the second shaft portion 33b of the shaft 33 protruding from the second side of each planetary gear 30 at an equal interval of 90 ° with respect to the circumferential direction around the central axis C1 of the planetary gear device 1. Hold on.
Elastic ring 60
The second shaft portion 33 b of each shaft 33 protruding from each bearing elongated hole 51 formed in the second carrier 50 penetrates either the first bearing hole 61 or the second bearing hole 62 formed in the elastic ring 60. It is supported. The first bearing hole 61 and the second bearing hole 62 have a circular cross section and support the second shaft portion 33b in a rotatable manner.

The elastic ring 60 is made of synthetic resin. As shown in FIG. 7, the elastic ring 60 has an elliptical outer shape when no external force is applied, and the central axis perpendicular to the intersection point P <b> 1 where the major axis and the minor axis intersect is the second elastic ring 60. When the shaft portion 33b is supported through, it coincides with the central axis C1 of the planetary gear device 1. Here, a line passing through the center position of the elastic ring 60 in the width direction (radial direction centering on the intersection P1) is referred to as an annular line Lz.

The elliptical elastic ring 60 is a second shaft portion projecting from the first set of planetary gears 30A at two positions on the long diameter line L1 intersecting the annular line Lz and facing each other across the intersection point P1. A first bearing hole 61 for penetrating and supporting 33b is provided. The elastic ring 60 is a second shaft portion that protrudes from the second set of planetary gears 30B at two positions on the short diameter line L2 intersecting the annular line Lz and facing each other across the intersection point P1. A second bearing hole 62 for penetrating and supporting 33b is provided.

Therefore, the first bearing hole 61 and the second bearing hole 62 have different distances to the intersection point P1. That is, the distance D1 to the intersection P1 of the first bearing hole 61 located on the long diameter line L1 is longer than the distance D2 to the intersection P1 of the second bearing hole 62 located on the short diameter line L2. In the present embodiment, the average value of the distance D1 and the distance D2 (= (D1 + D2) / 2) is a distance from the center axis of the sun gear 20 (center axis C1 of the planetary gear device 1) to the center axis of each planetary gear 30. Although it coincides with D0 (see FIG. 4), the relationship between D0, D1, and D2 may be a distance relationship that satisfies D1> D0 and D2 <D0.

Then, the second shaft portion 33b of the shaft 33 protruding from the two planetary gears 30A of the first set is passed through the first bearing holes 61 of the elastic ring 60, respectively, and the two planetary gears of the second set are set. The second shaft portion 33b of the shaft 33 protruding from 30B is passed through the second bearing hole 62 of the elastic ring 60, respectively.

At this time, the first bearing hole 61 of the elastic ring 60 tries to be elastically deformed and restored so that the distance D1 to the intersection P1 is shortened (in the shrinking direction). The second shaft portion 33b of 33 is given an elastic force in a direction away from the intersection P1.

As a result, the shaft 33 is a planetary gear 30A attached to the shaft 33 by rotating in a direction away from the central axis C1 along the bearing long hole 51 with the first shaft portion 33a as a fulcrum. The portion on the second shaft portion 33 b side of the external teeth 31 that mesh with the 10 internal teeth 11 is pressed against the internal teeth 11 of the internal gear 10.

On the other hand, the second bearing hole 62 of the elastic ring 60 tends to be elastically deformed and restored so that the distance D2 to the intersection P1 is increased (in the extending direction). The second shaft portion 33b is given an elastic force in a direction approaching the intersection P1.

As a result, the shaft 33 is a planetary gear 30B attached to the shaft 33 and rotated in the direction approaching the central axis C1 along the bearing long hole 51 with the first shaft portion 33a as a fulcrum. The portion of the external tooth 31 that meshes with the external tooth 21 on the second shaft portion 33 b side is pressed against the external tooth 21 of the sun gear 20.

In other words, when the planetary gear device 1 is stationary, the two planetary gears 30A of the first set are connected to the internal teeth 11 of the internal gear 10 without the portions of the external teeth 31 on the second shaft portion 33b side being rattled. It will be in the state of being pushed. Further, the second planetary gear 30B of the second set is in a state in which the portion of the outer teeth 31 on the second shaft portion 33b side is pressed against the outer teeth 21 of the sun gear 20 without rattling.

In addition, the four planetary gears 30 are pressed against the internal teeth 11 of the internal gear 10 or the external teeth 21 of the sun gear 20 by one elliptical elastic ring 60 without rattling. It becomes.

Here, for example, when the planetary gear device 1 is used with the first carrier 40 as an input shaft and the rotation shaft 22 of the sun gear 20 as an output shaft, the rotation shaft 22 of the sun gear 20 is input to the first carrier 40. It rotates in the same direction as the shaft and at a higher speed.

At this time, at the start of rotation, the four planetary gears 30 rattle against the internal teeth 11 of the internal gear 10 or the external teeth 21 of the sun gear 20 by one elliptical elastic ring 60, respectively. Since it rotates from the state where it is pushed and applied without rotation, there is no hitting sound caused by a plurality of simultaneous meshing of the planetary gear 30 due to backlash, and it rotates gently.

In addition, the first and second carriers 40 and 50 (elastic ring 60) include two planetary gears 30 as one set, and the two planetary gears 30 of each set face each other across the central axis C1. The two planetary gears 30A of the first set are spaced 90 degrees from the second planetary gear 30B of the second set about the central axis of the sun gear 20. Arranged.

Therefore, when the steady rotational torque of the first carrier 40 increases, the meshing action of the gears wins and the centering action works, the inclination of the shaft 33 of the planetary gear 30 by the elastic ring 60 is eliminated, and the same shaft rotation as that of a normal planetary gear is achieved. It becomes. As a result, the elastic ring 60 changes from an elliptical shape to a circular shape as shown in FIG. 8, and the first and second carriers 40 and 50 (elastic ring 60) are held in a well-balanced manner, thereby further improving the silent performance.

Here, the planetary gear unit 1 is used with the first carrier 40 as the input shaft and the rotation shaft 22 of the sun gear 20 as the output shaft, but the first carrier 40 is used as the output shaft and the rotation shaft 22 of the sun gear 20 is used as the output shaft. The input shaft, the internal gear 10 as an input shaft, the first carrier 40 as an output shaft, the first carrier 40 as an input shaft, and the internal gear 10 as an output shaft may be used. Further, the internal gear 10 may be used as an input shaft, the rotary shaft 22 of the sun gear 20 as an output shaft, the rotary shaft 22 of the sun gear 20 as an input shaft, and the internal gear 10 as an output shaft.

Next, effects of the planetary gear device 1 configured as described above will be described.
(1) According to this embodiment, at the start of rotation, the four planetary gears 30 are pressed against the internal teeth 11 of the internal gear 10 and the external teeth 21 of the sun gear 20 without rattling. Since it rotates from the state which was carried out, it can be made to rotate quietly without the hitting sound resulting from the simultaneous meshing | engagement of the planetary gear 30 by backlash.
(2) According to this embodiment, one elliptical elastic ring 60 rattles the four planetary gears 30 with respect to the internal teeth 11 of the internal gear 10 and the external teeth 21 of the sun gear 20, respectively. It is a member to be pressed without any problems.

Therefore, the structure and assembly are simplified and the cost can be reduced.
Second Embodiment Next, a planetary gear device according to a second embodiment of the present invention will be described with reference to the drawings.

The present embodiment is characterized by members that press the four planetary gears 30 against the internal teeth 11 of the internal gear 10 and the external teeth 21 of the sun gear 20, respectively, and these members are elastic rings of the first embodiment. 60.

Therefore, in this embodiment, for the sake of convenience of explanation, points different from the first embodiment will be described in detail, and the same reference numerals will be used for portions common to the first embodiment, and detailed description thereof will be omitted.

FIG. 9 shows the elastic ring 70 of the present embodiment. Like the elastic ring 60 of the first embodiment, the second shaft portion of each shaft 33 protruding from each bearing slot 51 formed in the second carrier 50. 33b is supported through.

The elastic ring 70 is made of synthetic resin. As shown in FIG. 9, the outer shape of the elastic ring 70 is a perfect circle when no external force is applied, and the central axis perpendicular to the center point P2 is supported by the elastic ring 70 penetrating each second shaft portion 33b. At the same time as the central axis C1 of the planetary gear unit 1.

The elastic ring 70 includes a first bearing hole 61 that penetrates and supports the second shaft portion 33b protruding from the first set of planetary gears 30A at two positions facing each other across the center point P2. Further, the elastic ring 70 is located at two positions opposite to each other with the center point P2 interposed therebetween, and at a distance of 90 ° with respect to the first bearing hole 61 about the center point P2, the second set of planetary gears 30B. 2nd bearing hole 62 which penetrates and supports the 2nd axis part 33b which projected from was provided.

The distance between the first bearing hole 61 and the second bearing hole 62 is different from the center point P2. That is, the first bearing hole 61 is formed near the outer surface of the elastic ring 70 and the second bearing hole 62 is formed near the inner surface of the elastic ring 70, and the center of the first bearing hole 61 is formed as in the first embodiment. The distance D1 to the axis is longer than the distance D2 to the center point P2 of the second bearing hole 62.

Then, the second shaft portion 33b of the shaft 33 protruding from the two planetary gears 30A of the first set is passed through the first bearing holes 61 of the elastic ring 70, respectively, and the two planetary gears of the second set are set. The second shaft portion 33b of the shaft 33 protruding from 30B is passed through the second bearing hole 62 of the elastic ring 70, respectively.

At this time, the first bearing hole 61 of the elastic ring 70 is elastically deformed and restored so that the distance D1 to the center point P2 is shortened (in the shrinking direction). The second shaft portion 33b of the shaft 33 is given an elastic force in a direction away from the center point P2.

As a result, the shaft 33 is a planetary gear 30A attached to the shaft 33 by rotating in a direction away from the center point P2 along the bearing elongated hole 51 with the first shaft portion 33a as a fulcrum. The portion on the second shaft portion 33 b side of the external teeth 31 that mesh with the 10 internal teeth 11 is pressed against the internal teeth 11 of the internal gear 10.

On the other hand, the second bearing hole 62 of the elastic ring 70 is elastically deformed and restored so that the distance D2 to the center point P2 becomes longer (in the extending direction). The second shaft portion 33b of 33 is given an elastic force in a direction approaching the center point P2.

As a result, the shaft 33 is the planetary gear 30B attached to the shaft 33 and rotated in the direction approaching the center point P2 along the bearing elongated hole 51 with the first shaft portion 33a as a fulcrum. The portion of the external tooth 31 that meshes with the external tooth 21 on the second shaft portion 33 b side is pressed against the external tooth 21 of the sun gear 20.

Therefore, when the planetary gear device 1 is stationary, the two planetary gears 30A of the first set are connected to the internal teeth 11 of the internal gear 10 without the back teeth of the external teeth 31 on the second shaft portion 33b side. It will be in the state of being pushed. Further, the second planetary gear 30B of the second set is in a state in which the portion of the outer teeth 31 on the second shaft portion 33b side is pressed against the outer teeth 21 of the sun gear 20 without rattling.

Moreover, the four planetary gears 30 are pressed against the internal teeth 11 of the internal gear 10 or the external teeth 21 of the sun gear 20 by one elastic ring 70 without rattling. Therefore, similarly to the first embodiment, the reduction in the number of parts, the structure, and the assembly can be simplified.

For example, when the first carrier 40 is rotated as the input shaft and the rotation shaft 22 of the sun gear 20 is rotated as the output shaft, the four planetary gears 30 are formed by one shape elastic ring 70 at the start of rotation. Rotating from the state of being pressed against the internal teeth 11 of the internal gear 10 or the external teeth 21 of the sun gear 20 without rattling, respectively, is caused by a plurality of simultaneous meshing of the planetary gear 30 due to backlash. It rotates gently without hitting.

When the steady rotational torque of the first carrier 40 increases, the meshing action of the gear wins and the centering action works, the inclination of the shaft 33 of the planetary gear 30 by the elastic ring 60 is eliminated, and the same shaft rotation as that of a normal planetary gear is achieved. It becomes. As a result, the distance D1 and the distance D2 are substantially equal, and the elastic ring 70 is changed from a circular shape to an elliptical shape shown in FIG. 10, and the first and second carriers 40 and 50 (elastic ring 60) are held in a balanced manner. Improve silent performance more.

As described above, the circular elastic ring 70 of the present embodiment is the same as the first embodiment by making the distances D1 and D2 to the central axis of the first bearing hole 61 and the second bearing hole 62 different from each other. It has a great effect.
Third Embodiment Next, a third embodiment of the planetary gear device of the present invention will be described with reference to FIGS.

This embodiment is characterized in that the

elastic rings

60 and 70 of the first and second embodiments are omitted, and the functions of the

elastic rings

60 and 70 are provided in the first and second carriers.

Therefore, in the present embodiment, for the sake of convenience of explanation, differences will be described in detail, and the same reference numerals are used for portions common to the first and second embodiments, and detailed description thereof is omitted.

11 shows the planetary gear device 1 of the present embodiment, and FIG. 12 shows the first carrier 80 that penetrates and supports the first shaft portion 33a of the shaft 33 protruding from the first side of each planetary gear 30. These show the 2nd carrier 90 which penetrates and supports the 2nd axial part 33b of the shaft 33 protruded from the 2nd side of each planetary gear 30. FIG.

The first carrier 80 is made of synthetic resin. The outer shape of the first carrier 80 is elliptical when no external force is applied, and the intersection point P1 where the major axis and minor axis intersect with each other is when the first carrier 80 supports each first shaft portion 33a. This coincides with the central axis C1 of the planetary gear device 1. Here, a line passing through the center position of the first carrier 80 in the width direction (radial direction centering on the intersection P1) is referred to as an annular line Lz.

The first carrier 80 having an elliptical shape is a first shaft projecting from the first set of planetary gears 30A at two positions on the long diameter line L1 intersecting the annular line Lz and facing each other across the intersection point P1. A first bearing hole 61 for penetrating and supporting the portion 33a is provided. Further, the first carrier 80 is a first shaft projecting from the second set of planetary gears 30B at two positions on the minor line L2 intersecting the annular line Lz and facing each other across the intersection P1. A second bearing hole 62 for penetrating and supporting the portion 33a is provided.

That is, as in the first embodiment, the first bearing hole 61 and the second bearing hole 62 have different distances to the intersection point P1, and the distance to the intersection point P1 of the first bearing hole 61 located on the long diameter line L1. D1 is longer than the distance D2 to the intersection P1 of the second bearing hole 62 located on the short diameter line L2.

Then, the first shaft portion 33a of the shaft 33 protruding from the two planetary gears 30A of the first set is passed through the first bearing holes 61 of the first carrier 80, respectively, and two planets of the second set are set. The first shaft portion 33a of the shaft 33 protruding from the gear 30B is passed through the second bearing hole 62 of the first carrier 80, respectively.

At this time, the first bearing hole 61 of the first carrier 80 is elastically deformed and restored so that the distance D1 to the intersection P1 is shortened (in the shrinking direction). The first shaft portion 33a of the shaft 33 is given an elastic force in a direction away from the central axis C1.

On the other hand, the second bearing hole 62 of the first carrier 80 tends to be elastically deformed and restored so that the distance D2 to the intersection P1 becomes longer (in the extending direction). The first shaft portion 33a of 33 is given an elastic force in a direction approaching the central axis C1.

FIG. 14 shows a second carrier 90 that penetrates and supports the second shaft portion 33b of the shaft 33 protruding from the second side of each planetary gear 30. FIG.

The second carrier 90 is made of synthetic resin. The second carrier 90 has an elliptical outer shape that is the same as that of the first carrier 80 in the state where no external force is applied, and the second carrier 90 is connected to the second carrier 90 at each intersection P1 where the major axis and minor axis intersect. When the shaft portion 33b is supported through, it coincides with the central axis C1 of the planetary gear device 1. Here, a line passing through the center position of the second carrier 90 in the width direction (radial direction centering on the intersection P1) is referred to as an annular line Lz.

The elliptical second carrier 90 is a second shaft protruding from the first set of planetary gears 30A at two positions on the long diameter line L1 intersecting with the annular line Lz and facing each other across the intersection point P1. A first bearing hole 61 is provided for penetrating and supporting the portion 33b. Further, the second carrier 90 is a second shaft projecting from the second set of planetary gears 30B at two positions on the short diameter line L2 intersecting the annular line Lz and facing each other across the intersection point P1. A second bearing hole 62 is provided for penetrating and supporting the portion 33b.

That is, the first bearing hole 61 and the second bearing hole 62 are different in distance to the intersection point P1 as in the first carrier 80, and the distance to the intersection point P1 of the first bearing hole 61 located on the long diameter line L1. D1 is longer than the distance D2 to the intersection P1 of the second bearing hole 62 located on the short diameter line L2.

Then, the second shaft portion 33b of the shaft 33 protruding from the two planetary gears 30A of the first set is passed through the first bearing holes 61 of the second carrier 90, respectively, and the two planets of the second set are set. The second shaft portion 33b of the shaft 33 protruding from the gear 30B is passed through the second bearing hole 62 of the second carrier 90, respectively.

At this time, the first bearing hole 61 of the second carrier 90 is elastically deformed and restored so that the distance D1 to the intersection P1 is shortened (in the shrinking direction). The second shaft portion 33b of the shaft 33 is given an elastic force in a direction away from the central axis C1.

On the other hand, the second bearing hole 62 of the second carrier 90 tends to be elastically deformed and restored so that the distance D2 to the intersection P1 is increased (in the extending direction), and thus the shaft that is penetrated and supported by the second bearing hole 62. The first shaft portion 33a of 33 is given an elastic force in a direction approaching the central axis C1.

Therefore, when the planetary gear device 1 is stationary, the first and second planetary gears 30A are configured such that the first and

second carriers

80 and 90 intersect the first and

second shaft portions

33a and 33b of the shaft 33 at the same time. By applying an elastic force in a direction away from P1 and restoring it, it is pushed against the internal teeth 11 of the internal gear 10 without rattling.

When the planetary gear device 1 is stationary, the second planetary gear 30B of the second set includes the first and

second carriers

80 and 90 that intersect the first and

second shaft portions

33a and 33b of the shaft 33 at the same time. By applying and restoring the elastic force in the direction approaching P1, the outer teeth 21 of the sun gear 20 are pushed and attached without rattling.

That is, when the planetary gear device 1 is stationary, the two planetary gears 30A of the first set are pressed against the internal teeth 11 of the internal gear 10 without the entire internal gear 10 side of the external teeth 31 being rattled. It becomes a state. Further, the two planet gears 30B of the second set are in a state of being pressed against the outer teeth 21 of the sun gear 20 without rattling the entire outer teeth 31 of the sun gear 20 side.

Moreover, the four planetary gears 30 are pushed by the first carrier 80 and the second carrier 90 against the internal teeth 11 of the corresponding internal gear 10 or the external teeth 21 of the sun gear 20 without rattling. It will be attached. Therefore, unlike the first and second embodiments, the

elastic rings

60 and 70 are unnecessary, and the number of parts can be reduced, and the structure and assembly can be simplified. In addition, since the first carrier 80 and the second carrier 90 have the same shape, they can be shared with each other and parts management is facilitated.

Here, for example, when the planetary gear device 1 is used with the internal gear 10 as an input shaft and the rotary shaft 22 of the sun gear 20 as an output shaft, the rotary shaft 22 of the sun gear 20 is opposite to the input shaft of the internal gear 10. Rotate at an increased speed in the direction.

At this time, at the start of rotation, the four planetary gears 30 are respectively corresponding to the internal teeth 11 of the corresponding internal gear 10 or the external teeth 21 of the sun gear 20 in the first carrier 80 and the second carrier 90, respectively. Since each of them rotates from a state where they are pushed without rattling, they rotate quietly without hitting sound caused by a plurality of simultaneous meshing of the planetary gear 30 due to backlash.

When the steady rotational torque of the first and

second carriers

80 and 90 increases, the meshing action of the gears wins and the centering action works, and the inclination of the shaft 33 of the planetary gear 30 by the first and

second carriers

80 and 90 is increased. And the same axis rotation as a normal planetary gear. As a result, the first and

second carriers

80 and 90 are changed from the elliptical shape to the circular shapes shown in FIGS. 13 and 15, respectively, and the first and

second carriers

80 and 90 are held in a well-balanced manner to further improve the silent performance.

Here, the case where the planetary gear device 1 is used with the internal gear 10 as the input shaft and the rotating shaft 22 of the sun gear 20 as the output shaft has been described. However, the present invention is not limited to this, as described above. The internal gear 10 may be used as an output shaft, and the rotary shaft 22 of the sun gear 20 may be used as an input shaft.

The above embodiment may be modified as follows.

In the first and second embodiments, the shape of the bearing hole 41 formed in the first carrier 40 that penetrates and supports the first shaft portion 33a of the shaft 33 protruding from the first side of each planetary gear 30 is illustrated in FIG. As shown in FIG. 16, the inner diameter of the planetary gear 30 may be increased toward the planetary gear 30.

Thus, when the shaft 33 is rotated by the elastic ring 60 with the bearing hole 41 as a fulcrum, the rotation of the shaft 33 can be facilitated.

In the third embodiment, both the first carrier 80 and the second carrier 90 have the function of the elastic ring 60, but either one may have the function of the elastic ring 60. .

In the third embodiment, the shapes of the first carrier 80 and the second carrier 90 are the same as the elliptical elastic ring 60 of the first embodiment, but the circular elastic ring 70 of the second embodiment and It may be carried out in the same manner, and the circumferential positions of the first carrier 80 and the second carrier 90 may be shifted from each other by 90 degrees.

The first embodiment is specifically described in the planetary gear device 1 in which the internal gear 10, the sun gear 20, the four planetary gears 30, and the first and

second carriers

40 and 50 are arranged in the cylindrical gear case 2. However, the gear case 2 may be omitted. For example, such an embodiment may be embodied in the planetary gear device 1 in which the sun gear 20, the four planetary gears 30, the first and

second carriers

40 and 50 are arranged in the internal gear 10.

In the first embodiment, the planetary gear 30 is supported so as to be rotatable in the radial direction with respect to the shaft 33 and immovable in the thrust direction, but is not rotatable in the radial direction with respect to the shaft 33. It may be fixed. In this case, the shaft 33 can be integrally formed with the same synthetic resin as the planetary gear 30.

In this case, the shaft 33 needs to be supported rotatably with respect to the first and

second carriers

40 and 50.

In the first to third embodiments, the internal gear 10, the sun gear 20, the four planetary gears 30, the first and

second carriers

40, 50, 80, 90, and the

elastic rings

60, 70 are molded from synthetic resin. However, you may shape | mold with metals, such as rubber | gum, aluminum, stainless steel, and iron.

Claims

A planetary gear set,
A sun gear having a central axis;
Four planetary gears connected and supported by two carriers at equal intervals in the circumferential direction, the four planetary gears being one set, and the two planetary gears of each set being sun gears 4 planetary gears that are opposed to each other with each planetary gear supported by a support shaft,
The support shafts of the four planetary gears are integrally connected in the circumferential direction around the sun gear, and the support shafts of the two planetary gears of the first set facing each other with the sun gear interposed therebetween, The internal gear and the sun gear are provided on the support shafts of a second set of two planetary gears that impart elastic force in one direction of the internal gear and the sun gear and are opposed to each other with the sun gear interposed therebetween. An elastic ring for applying an elastic force in the other direction of the gear;
A planetary gear device comprising:
The planetary gear set according to claim 1,
The elastic ring is an elliptical elastic ring having a major axis and a minor axis,
The elastic ring has a pair of first bearing holes at two positions on the long diameter line across the intersection where the major axis and the minor axis intersect, and at the center position of the radial width of the elastic ring, and the intersection A pair of second bearing holes at two positions on the short-diameter line across the center of the radial width of the elastic ring,
The pair of first bearing holes are elastically deformed in the first set of two planetary gear support shafts, and the pair of second bearing holes are in the second set of two planetary gear support shafts. Connected planetary gear unit.
The planetary gear set according to claim 1,
The elastic ring is a perfect circular elastic ring,
The elastic ring has a pair of first bearing holes at two positions of the elastic ring on a first line passing through a central point of the elastic ring and at an equal first distance across the central point;
A pair of elastic rings on a second line that passes through the center point of the elastic ring and is perpendicular to the first line and is equal to the center point and at a second distance shorter than the first distance. A second bearing hole,
The pair of first bearing holes are elastically deformed in the first set of two planetary gear support shafts, and the pair of second bearing holes are in the second set of two planetary gear support shafts. Connected planetary gear unit.
In the planetary gear set according to claim 2 or 3,
Each of the support shafts of the four planetary gears has a first shaft portion and a second shaft portion,
The two carriers include a first carrier that connects and supports the first shaft portions of the support shafts of the four planetary gears, and a planet that connects and supports the second shaft portions of the support shafts of the four planetary gears. A second carrier opposite to the first carrier with respect to the gear,
The elastic ring is a planetary gear device that is arranged on the second carrier and is connected by elastically deforming the second shaft portions of the support shafts of the four planetary gears.
In the planetary gear set according to claim 2 or 3,
The elastic ring is a planetary gear device constituted by the two carriers that integrally connect the support shafts of the four planetary gears to the central axis in the circumferential direction.
In the planetary gear set according to claim 2 or 3,
The bearing hole formed in the first carrier has a circular cross section, and the bearing hole formed in the second carrier is a planetary gear that is a long hole in the radial direction centered on the central axis of the planetary gear device. apparatus.
The planetary gear set according to claim 6,
The elongated bearing hole formed in the second carrier is a planetary gear device in which the narrow interval coincides with the diameter of the support shaft, and the wide interval is longer than the diameter of the support shaft.
The planetary gear device according to any one of claims 1 to 7,
A planetary gear device, wherein a shape of a bearing hole formed in the carrier that penetrates and supports the support shaft protruding from one side of the planetary gear is formed such that an inner diameter thereof is expanded toward the planetary gear.
The planetary gear device according to any one of claims 1 to 8,
A planetary gear device in which the internal gear, the sun gear, the four planetary gears, and the carrier are arranged in a cylindrical gear case.
The planetary gear device according to any one of claims 1 to 7,
A planetary gear device in which the sun gear, the four planetary gears, and the carrier are arranged in the internal gear.