JP2571381B2 - Planetary roller type power transmission device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planetary roller type power transmission device for transmitting power at a reduced or increased speed between two rotating shafts.

<Prior Art> A conventional planetary roller type power transmission device of this type will be described with reference to FIGS. 6 and 7. FIG.

In the figure, reference numeral 1 denotes a first rotating shaft, and reference numeral 2 denotes a sun roller integrally formed on the shaft end of the first rotating shaft 1.

Reference numeral 3 denotes a second rotating shaft arranged coaxially with the first rotating shaft 1, and a carrier 4 is integrally formed at the shaft end of the second rotating shaft 3.

Reference numeral 5 denotes the first rotating shaft 3 via a rolling bearing 6.
The casing is externally fitted to a portion where the rotating shaft 1 and the second rotating shaft 3 are opposed to each other.

Reference numeral 7 denotes a fixed wheel fixed to the inner surface of the casing 5 so as to be concentric with the sun roller 2.

A plurality of planetary rollers 8 are interposed between the fixed wheel 7 and the sun roller 2 in a state where they are pressed against each other.

Reference numeral 9 denotes a planet shaft whose one end is fixed to the carrier 4 and whose free end is inserted through the planetary roller 8 via the needle roller bearing 10.

Needle roller bearing 10 consists of roller 10a and cage 10b
And the inner ring 10c.

As an operation, for example, when the sun roller 2 is rotated together with the first rotating shaft 1, each of the planetary rollers 8 revolves while rotating, and the planetary shaft 9 rotates around the sun roller 2 due to the revolving, and the carrier 4 passes through the carrier 4. The number of revolutions of the planetary roller 8 is taken out from the second rotating shaft 3 to form a reduction gear. Conversely, when power is taken out from the first rotating shaft 1 by rotating the second rotating shaft 3, a speed increasing device is used.

The planetary roller type power transmission device having such a configuration has the following problems.

In the first place, a plurality of planetary shafts 9 which are conventionally arranged at positions mutually determined by the carrier 4 are combined with a planetary roller 9 whose center is located on a predetermined circumference centered on the center of the fixed wheel 7 and the sun roller 2. 8, the planetary shaft 9 cannot be inserted into the planetary roller 8 if any one of the planetary shafts 9 is displaced from the circumference due to a manufacturing error. In addition, if it is forcibly inserted, an excessive force is applied to the planetary shaft 9, so that smooth driving cannot be expected.

Therefore, even if the positional relationship between the axis of the planetary shaft 9 and the axis of the inner ring 10c is deviated due to a manufacturing error, the planetary shaft 9 can be inserted into the inner ring 10c without applying an excessive force to each of them. Inner ring 10c of shaft 9 and needle roller bearing 10
And a small assembly gap is provided between them.

Since this minute assembly gap provides play corresponding to the backlash of the gear mechanism in the revolving direction of the planetary roller 8, the first
The responsiveness between the rotating shaft 1 and the second rotating shaft 3 is deteriorated.

Therefore, a planetary roller type power transmission device as disclosed in Japanese Patent Application Laid-Open No. 61-84455 has been proposed for the purpose of improving the responsiveness between both rotating shafts while facilitating assembly.

 This will be described with reference to FIGS. 8 to 10.

In the drawings, the same reference numerals as those shown in FIGS. 6 and 7 indicate the same parts or corresponding parts, and only the configuration different from the above-described conventional example will be described.

A minute assembly gap is provided between the planetary shaft 9 and the inner ring 10c of the needle roller bearing 10, and even if the positional relationship between the center of the planetary shaft 9 and the center of the inner ring 10c is shifted due to a manufacturing error, the inner ring 10c is not provided. , So that the planetary shaft 9 can be inserted without applying excessive force.

In order to eliminate such a minute assembly gap, the following configuration is adopted.

On the free end side of the planetary shaft 9, parallel flat surfaces 11, 12 facing each other are formed along the radial direction of the fixed wheel 7, and these flat surfaces 11, 12 are formed.
A space X, Y having a substantially arc-shaped cross section is formed between the inner ring 10c and the inner ring 10c of the needle roller bearing 10.

The movable member 13 having a substantially arc-shaped cross section is fitted into one of the bow-shaped spaces X, and the movable members 14 and 15 having a substantially sector-shaped cross section are fitted into the other bow-shaped space Y.
A wave-like elastic member 16 for urging them in directions away from each other is interposed therebetween.

That is, the elastic force of the elastic member 16 causes the two movable members 14, 15 to move.
To the outside in the radial direction and the center in the radial direction,
The two movable members 14, 15 are connected to the inner ring 1 of the needle roller bearing 10.
By pressing the planetary roller 8 against the inner surface of the planetary roller 9 to eliminate play in the revolving direction of the planetary roller 8 by eliminating the minute assembly gap between the planetary shaft 9 and the inner ring 10c.

<Problems to be Solved by the Invention> However, the conventional planetary roller type power transmission device has the following problems.

Conventionally, a minute assembly gap, which is not preferable in the above configuration, is provided between the planetary roller 8 and the planetary shaft 9,
Then, the minute assembly gap is removed by a component provided between the planetary roller 8 and the planetary shaft 9.

In the configuration for eliminating the minute assembly gap, since the elastic member 16 having insufficient rigidity is used, the elastic member 16 may be deflected by a load applied during power transmission.

When the elastic member 16 bends, both movable members 14 and 1 of the elastic member 16 are bent.
Since the urging force on the member 5 is weakened, the minute assembly gap cannot be completely eliminated.

Therefore, in the planetary roller type power transmission device described in JP-A-61-84455, the play corresponding to the backlash of the gear mechanism in the revolving direction of the planetary roller 8 cannot be completely removed, and the first rotating shaft It was insufficient to improve the response between the first and second rotating shafts 3.

The present invention has been made in view of such circumstances,
Even if there is misalignment due to a manufacturing error, it is possible to easily assemble without giving an unreasonable burden to each part, and to completely eliminate the play in the revolving direction of the planetary roller to respond between the two rotating shafts. The purpose is to improve the properties.

<Means for Solving the Problems> The present invention has the following configuration in order to achieve such an object.

That is, the planetary roller type power transmission device according to the present invention includes:
A sun roller connected to the first rotating shaft, a fixed wheel concentrically arranged on the outer periphery of the sun roller, and a pressure wheel interposed between the fixed wheel and the sun roller,
A plurality of planetary rollers having a supported portion formed at both ends, a carrier formed on a second rotating shaft coaxially arranged with respect to the first rotating shaft, and a negative gap between the supported portions of each of the planetary rollers; The vehicle includes a plurality of planetary roller support members that are connected via a rolling bearing and are combined in an annular shape, and a fixing member that connects the planetary roller support members to the carrier in an axially opposed state.

<Operation> The operation according to the configuration of the present invention is as follows.

Since the roller bearing in the negative gap state is interposed between the planetary roller and the planetary roller support member, there is no play corresponding to the backlash of the gear mechanism between the planetary roller and the planetary roller support member, and the first rotation The responsiveness between the shaft and the second rotation shaft is improved.

In addition, since all of the planetary roller support members are independent from each other, even if the positional relationship between the two planetary roller support members is shifted when the respective planetary roller support members are mounted on the planetary rollers, each of the other planetary roller support members may be displaced. Not interfered by Therefore, no unreasonable force is applied to either the planetary roller or the planetary roller support member.

In the present invention, since each of the plurality of planetary roller support members is formed as a single unit, there is a possibility that a positional shift may occur at each connecting portion between the planetary roller support member and the carrier.

However, even if there is such a displacement, when attaching each planetary roller support member to the carrier, both are superimposed in the axial direction, and this portion is fixed in the axial direction by a fixing member, so that the displacement is absorbed. However, each planetary roller support member is fixed to the carrier without giving excessive force.

<Example> Hereinafter, one example of the present invention will be described in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention.

In the figure, reference numeral 20 denotes a first rotation axis, reference numeral 30 denotes a second rotation axis arranged coaxially with the first rotation axis 20, and reference numeral 40 denotes a first rotation axis.
A sun roller integrally formed on the shaft end of 20, a reference numeral 50 denotes a fixed wheel fixed to an inner surface of a casing (not shown), a reference numeral
Reference numeral 60 denotes a plurality of (in this embodiment, three circumferentially equally spaced) stepped planetary rollers interposed in a press-contact state between the sun roller 40 and the fixed wheel 50, and reference numeral 70 denotes a needle roller bearing.
80 is a carrier formed integrally with the shaft end of the second rotating shaft 30;
Reference numeral 90 denotes an annular plate fitted to the first rotation shaft 20 so as to be rotatable relative to the outside, and reference numerals A to F denote planetary roller support members, respectively.

The stepped planetary roller 60 has a large-diameter cylindrical portion 61 at the center and small-diameter cylindrical portions 62 and 63 as supported portions corresponding to a conventional planetary shaft at both axial ends.

The large-diameter cylindrical portion 61 is interposed between the sun roller 40 and the fixed wheel 50 in a press-contact state, and in this state, both small-diameter cylindrical portions 62 and 63 are provided on both axial sides of the sun roller 40 and the fixed wheel 50. Each protrudes.

Since the stepped planetary roller 60 of this embodiment has the conventional planetary roller and the planetary shaft integrally formed, there is no minute assembly gap between the planetary roller and the planetary shaft unlike the conventional case.

The needle roller bearing 70 includes a plurality of rollers 71, a retainer 72 that rotatably holds each of the rollers 71, and an outer ring 73.

Each of the needle roller bearings 70 is attached to each of the small-diameter cylindrical portions 62 and 63 of the planetary roller 60 in a state having a negative gap, and the planetary roller support members A to F are fitted around the outer periphery of the needle roller bearings 70 by press fitting. .

The carrier 80 includes a plurality (three in this embodiment) of protruding pieces 81 to 83 radially extending in the radial direction.

A circular bolt mounting hole 84 is provided at the free end side of each of the projections 81 to 83.
~ 86 are drilled respectively.

The annular plate 90 has a circular through-hole 91 at the center, and has protruding pieces 92 to 94 extending radially in the radial direction. Bolt mounting holes 95 to 97 are formed in the protruding pieces 92 to 94, respectively.

Each of the planetary roller support members A to F is combined in an annular shape, and has a small diameter cylindrical portion 6 of the stepped planetary roller 60.
Maru together has a recess a ₁ ~f ₁ circular fitting to 2,63,
And a first projecting piece a ₂ ~f ₂ and the second protrusion a ₃ ~f ₃ extends curved in opposite directions.

The first projecting piece a ₂ ~f ₂ and the second protrusion a ₃ ~f ₃ bolt mounting holes _{a 4 ~f 4, a 5 ~f} 5 are respectively bored.

Each bolt mounting hole a _{4 to} f ₄ , a of the planetary roller support members A to F
₅ diameter of ~f ₅ is set larger as the bolt 100 to 102 described below is loosely fitted, projecting pieces projecting pieces 81 to 83 each bolt mounting holes 84 to 86 and the annular plate 90 of the carrier 80 92 to
94 The diameter of each bolt mounting hole 95-97 is
It is set slightly larger than the diameter of 0 to 102.

Then, the planetary roller support first member A~C each protrusion a ₂ to c ₂ and a second projecting pieces projecting piece a ₃ to c ₃ carrier 80 81
To 83, and the first of each of the planetary roller support members DF.
Protrusion d ₂ ~f ₂ and the second projecting piece d ₃ ~f ₃ are respectively attached by bolts 100 to 102 and a nut which is fixed member projecting pieces 92 to 94 of the annular plate 90.

Specifically, the bolt 100 includes a bolt mounting hole 84 of the projecting piece 81 of the carrier 80, the first bolt mounting hole a ₄ projecting pieces a ₂ of the planetary roller support member A, the second protrusion of the planetary roller support member B b ₃ bolt mounting hole b ₅ and the first protrusion d ₂ of the planetary roller support member D
And the bolt mounting holes d _4, second protrusion of the planetary roller support member E
a bolt mounting hole e ₅ of e _3, are inserted successively into the bolt mounting hole 95 of the protrusion 92 of the annular plate 90, a first projecting piece a planetary roller support members A to protrusion 81 of the carrier 80 ₂ and the planetary roller support member at a second nut protrusion b ₃ is screwed to the bolt 100 of B, also the first projecting piece d ₂ and the planetary roller support member of the planetary roller support member D to protrusion 92 of the annular plate 90 are fixed in the second two nuts protrusion e ₃ is screwed to the bolt 100 of the E.

Also, bolt 101 includes a bolt mounting hole 85 of the projecting piece 82 of the carrier 80, the bolt mounting hole a ₅ second protrusion a ₃ planetary roller support member A, the first projecting piece c of the planetary roller support member C and ₂ of the bolt mounting holes c _4, the bolt mounting holes d ₅ of the second projecting piece d ₃ of the planetary roller support member D, the first bolt mounting holes f ₄ projecting pieces f ₂ of the planetary roller support member F, cyclic The protrusions 93 of the plate 90 are continuously inserted into the bolt mounting holes 96 of the
82 first protrusion c ₂ of the second protrusion a ₃ and the planetary roller support member C of the planetary roller support member A with the nuts screwed to the bolt 101, also the planetary roller support member on the projecting pieces 93 of the annular plate 90 the first projecting piece f ₂ of the second projecting piece d ₃ and the planetary roller support member F of D is fixed at each of the two nuts screwed on the bolts 101.

Further, the bolt 102 includes a bolt mounting hole 86 of the projecting piece 83 of the carrier 80, the first bolt mounting holes b ₄ projecting piece b ₂ of the planetary roller support member B, the second projecting piece c of the planetary roller support member C a bolt mounting hole c _{5 3,} the first bolt mounting hole e ₄ projecting pieces e ₂ of the planetary roller support member E, the second projecting piece f ₃ of the planetary roller support member F
Bolt the mounting holes f _5, is inserted through continuously in the bolt mounting hole 97 of the projecting piece 94 of the annular plate 90, the first projecting piece b ₂ and the protrusion 83 of the carrier 80 of the planetary roller support member B of nuts second protrusion c ₃ of the planetary roller support member C is screwed to the bolt 102, also the first projecting piece e ₂ and the planetary roller support member F of the planetary roller support member E to protrusion 94 of the annular plate 90 Second
Are fixed by two nuts protrusion f ₃ is screwed to the bolt 102.

As described above, in the present embodiment, the small-diameter cylindrical portions 62 and 63 at both axial ends of the stepped planetary roller 60 are combined with the carrier 80 and the annular plate 9.
Since both ends are supported at 0, the stepped planetary roller 60 rotates and revolves in a state where it is always parallel to the axis of the first rotating shaft 20 and the second rotating shaft 30.

In the planetary roller type power transmission device of the present embodiment, the needle roller bearing 70 interposed between the small-diameter cylindrical portions 62 and 63 of each stepped planetary roller 60 and the planetary roller support members A to F has a negative gap. Since there is provided, there is no play (corresponding to the backlash of the gear mechanism) between each stepped planetary roller 60 and each of the planetary roller support members A to F.

In addition, even if the axial positions of the small-diameter cylindrical portions 62 and 63 of the stepped planetary roller 60 are slightly shifted in the circumferential direction due to a manufacturing error, the planetary rollers can be positioned with respect to the small-diameter cylindrical portions 62 and 63 of the stepped planetary roller 60. When mounting the support members A to F, all the planetary roller support members A to F are independent and independent from each other, and these planetary roller support members do not interfere with each other, so that the mounting is easily performed. be able to.

Furthermore, since the diameter of the mounting hole 95 to 97 of the mounting hole 84 to 86 and the annular plate 90 of the carrier 80 is larger than the bolts 100 to 102, the mounting holes of the planetary roller support member A~F a ₄ ~f _4, a ₅ ~ F
_{Even if} the axis of ₅ does not coincide with the axes of the mounting holes 84 to 86 of the carrier 80 and the mounting holes 95 to 97 of the annular plate 90, the planetary roller supporting members A to
F can be firmly fixed to the carrier 80 and the annular plate 90, so that no excessive force is applied to the stepped planetary roller 60.

In the above embodiment, the stepped planetary roller 60 having the small-diameter cylindrical portions on both sides in the axial direction is used, and the planetary roller supporting members A to F having the concave portions are used, but the small-diameter cylindrical portions and the concave portions are reversed. Relationship can be provided. In other words, the small-diameter cylindrical portion of the stepped planetary roller 60 is eliminated, and a planetary roller having a cylindrical portion as a supported portion at the shaft end or a cylindrical planetary roller having a through hole at the center is used, and a planetary roller supporting member is used. With respect to A to F, a shaft that can be inserted through a rolling bearing into a cylindrical portion or a through hole of the planetary roller can be formed without a concave portion.

In the above embodiment, the planetary roller supporting members A to F are arranged on both sides of the stepped planetary roller 60 in order to support both small diameter cylindrical portions 62 and 63 of the stepped planetary roller 60. However, the present invention is not limited to this. For example, it may be one that supports the stepped planetary roller 60 only on one side.

Further, in the above embodiment, the needle roller bearing is provided between the stepped planetary roller 60 and the planetary roller support members A to F.
Although 70 is interposed, the present invention is not limited to this. For example, it is also possible to use an angular ball bearing. In this case, a pressure is applied to the angular ball bearing by a tightening force between the bolts 100 to 103, which are the fixing members, and the nut to make a negative gap.

In addition, the shapes of the planetary roller support members A to F, the carrier 80, and the annular plate 90 are not limited to those described above, and it goes without saying that various modifications are possible.

<Effects of the Invention> According to the present invention, the following effects are exhibited.

That is, since a rolling bearing in a negative gap state is interposed between the planetary roller and the planetary roller supporting member to eliminate play (equivalent to backlash of the gear mechanism) between the two, the first rotating shaft and the second rotating shaft are provided. The responsiveness between the shaft and the shaft can be improved.

Therefore, when the planetary roller type power transmission device of the present invention is used particularly as a speed increasing device or a speed reducing device of an industrial robot or the like, a stable operation without displacement can be realized.

Moreover, since the independent planetary roller support members are individually mounted on the planetary rollers, even if the positional relationship between them is shifted due to a manufacturing error of each component,
Regarding the mounting of the planetary roller support member on the planetary roller, the planetary roller support member is not interfered with by other planetary roller support members.

That is, since the mounting work can be easily performed without forcibly displacing the two, an unreasonable load is not imposed on the both.

[Brief description of the drawings]

1 to 4 relate to an embodiment of the present invention, and FIG.
The figure is a longitudinal sectional side view showing a planetary roller type power transmission device.
The figure is a cross-sectional view taken along the line II-II in FIG. 1, and FIG.
FIG. 4 is a perspective view of the planetary roller support member, and FIG. 5 is a top view of the planetary roller support member. 6 to 10 relate to a conventional example, and FIG. 6 is a longitudinal side view showing a general planetary roller type power transmission device.
FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. 6, FIG. 8 is a half vertical sectional side view showing a planetary roller type power transmission device described in Japanese Patent Application Laid-Open No. 61-84455, and FIG. FIG. 8 is a sectional view taken along line IX-IX of FIG. 8, and FIG. 10 is a perspective view of the elastic member. 20 First rotary shaft 30 Second rotary shaft 40 Sun roller 50 Fixed wheel 60 Stepped planetary roller 70 Needle roller bearing (rolling bearing) 80 Carriers AF Planetary roller support member 100 to 102 …… Bolts.

Claims (4)

(57) [Claims] 1. A sun roller connected to a first rotating shaft, a fixed wheel concentrically disposed on the outer periphery of the sun roller, and a pressure wheel interposed between the fixed wheel and the sun roller. A plurality of planetary rollers having supported portions formed at both ends, a carrier formed on a second rotating shaft arranged coaxially with the first rotating shaft, and a negatively charged portion supported by each of the planetary rollers. A plurality of planetary roller support members that are connected via a rolling bearing in a clearance state and are combined in an annular shape; and a fixing member that connects the planetary roller support members in a state where they are opposed to the carrier in the axial direction. A planetary roller type power transmission device, 2. The method according to claim 1, wherein the planetary roller is a stepped planetary roller having a small-diameter cylindrical portion as a supported portion at a shaft end, and the planetary roller supporting member is rolled on the small-diameter cylindrical portion of the stepped planetary roller. 3. The planetary roller type power transmission device according to claim 1, wherein the power transmission device has a recess which is press-fitted through a bearing. 3. A shaft wherein the planetary roller has a cylindrical portion as a supported portion at a shaft end, and wherein the planetary roller supporting member is inserted into the cylindrical portion of the planetary roller via the rolling bearing. The planetary roller type power transmission device according to claim 1, further comprising: 4. A fixing member comprising: a bolt inserted into a bolt mounting hole formed in each overlapping portion between the planetary roller support member and the carrier; and a nut screwed to the bolt. The planetary roller type according to claim (1), wherein at least one of the bolt mounting holes of the planetary roller support member and the carrier is larger than the diameter of the bolt. Power transmission device.