JP2646096B2 - Power transmission device - Google Patents

Description

The present invention relates to a power transmission device for a planetary mechanism using a ball as a planetary rolling element.

<Prior Art> Conventionally, a power transmission device of a planetary mechanism as shown in FIG. 3 has been known.

That is, in the drawing, reference numeral 1 denotes a fixed outer ring whose inner peripheral surface is formed into a partially spherical shape, 2 denotes a first rotation shaft, 3 denotes a first rotation shaft 2
The second rotary shaft, which is coaxially disposed and inserted into the hollow interior of the fixed outer ring 1, 4 is a cylindrical roller (planetary rolling element) having a partially spherical spherical surface, and 5 is the axis of the first rotary shaft 2. Carriers 6 provided at the ends indicate planetary shafts provided on the fixed shaft ends between the carrier 5 and the annular plate 7, respectively.

A pair of two annular bodies 8, 9 each having a partially spherical peripheral surface are attached to the outer peripheral surface of the shaft end of the second rotary shaft 3, and are fixed to the outer peripheral surfaces of the annular bodies 8, 9 respectively. A cylindrical roller 4 is interposed between the outer ring 1 and the inner peripheral surface in a press-contact state.

The cylindrical roller 4 is rotatably fitted to the planetary shaft 6 via a plurality of needle rollers 10.

In such a power transmission device, for example, when the first rotating shaft 2 is used as an input shaft, it can be used as a speed increasing device, and when the second rotating shaft 3 is used as an input shaft, deceleration can be performed. It can be used as a device.

By the way, it has been pointed out that this type of power transmission device is not suitable for high-speed rotation because the power loss is large, such as the skew of the needle roller 10 between the cylindrical roller 4 and the planetary shaft 6. You.

Thus, as an example of a power transmission device used for high-speed rotation, a device as disclosed in Japanese Utility Model Publication No. 51-29418 is known.

This will be described with reference to FIGS. 4 and 5. FIG. In the figure, reference numeral 11 denotes a fixed outer ring,
The first and second rotating shafts 12 and 13 are coaxially arranged facing each other. A cylindrical carrier 14 is formed at the shaft end of the first rotating shaft 12, and the second rotating shaft 13 is inserted into the carrier 14.

Reference numerals 15 and 16 denote two pairs of annular bodies that form an annular groove on the inner peripheral surface of the fixed outer ring 1.
There are a plurality of balls 18 between the groove 17 formed in the
(Planetary rolling element) is assembled in a pressed state.

The plurality of balls 18 are respectively held in a plurality of pockets 19 formed in the carrier 14, and each of them rotates synchronously.

A pressing spring 21 is provided between the one ring 15 and the plate 20 screwed to the fixed outer ring 11,
By changing the degree of screwing of the plate 20 to the fixed outer ring 11, the pressing force of the ring 15 against the ball 18 is changed,
The configuration is such that the rolling resistance of the ball 18 can be adjusted.

<Problems to be Solved by the Invention> By the way, the conventional example having such a configuration also has the following problems.

That is, since each of the plurality of balls 18 was held by merely fitting it into the pocket 19 of the carrier 14, the pocket 19
The inner peripheral surface and the ball 18 come into sliding contact with each other, and particularly when used at a high speed rotation, the contact portion abnormally generates heat and results in burning.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a power transmission device capable of realizing smooth high-speed rotation without seizure or the like.

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

That is, the power transmission device of the present invention includes a hollow cylindrical portion of a fixed outer ring, a first and a second rotating shafts disposed coaxially opposed to each other, and a circumference between the second rotating shaft and the fixed outer ring. A plurality of equally-arranged planetary rolling elements, and provided at the shaft end of the first rotary shaft, extend in a space between the second rotary shaft and the fixed outer ring, and move the planetary rolling elements in a radial direction. A carrier that is accommodated in a pocket penetrated through the carrier and rotatably holds the planetary rolling element, wherein the planetary rolling element is a ball, and a shaft is pressed into the center of the ball in a penetrating state. The both ends of this shaft are pivotally supported via a ball bearing in holes formed continuously on both axial sides of the pocket of the carrier.

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

That is, the shaft which becomes the rotation axis of the ball is press-fitted into the center of the ball, and the ball is axially supported by the holes provided on both sides in the axial direction in the pocket of the carrier via the ball bearing. High-speed rotation becomes possible.

Moreover, since the sliding contact portion with respect to the ball is eliminated, the seizure due to abnormal heat generation as in the related art is avoided.

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

1 and 2 show an embodiment of the present invention.

In the illustrated power transmission device 30, reference numeral 31 denotes a housing, and a thin hollow cylindrical portion is formed at one end of the housing 31, and the thin portion constitutes a fixed outer ring 32. A pair of two annular bodies 33 and 34 having a tapered inner peripheral surface are attached to the inner peripheral surface of the fixed outer ring 32 so as to form a substantially “V” -shaped annular groove.

Further, a first rotary shaft 35 is rotatably supported on the hollow cylindrical portion of the thick body portion of the housing 31 via rolling bearings 36 and 37, and a second rotary shaft 38 is mounted on the hollow cylindrical portion of the fixed outer ring 32. It is inserted concentrically. The second rotating shaft 38 is disposed coaxially opposite to the first rotating shaft 35.

At one end of the first rotating shaft 35, a plurality of carriers 39 (three in this embodiment) located in an annular space between the fixed outer ring 32 and the second rotating shaft 38 are provided, and the other end is provided at the housing 31. Protrudes from the opening end on the side of the thick main body.

One end of the second rotating shaft 38 is rotatably supported on a base end side inner peripheral portion of the carrier 39 via a rolling bearing 40, and the other end protrudes from the opening end on the fixed outer ring 32 side.

A long hole 41 is formed in each of the carriers 39 along the axial direction, and a pocket 42 penetrating in the radial direction is formed at a substantially central position of the carrier 39. Deep groove type ball bearings 43 and 44 are positioned and fixed on the deep side and open end side of the long hole 41 of the carrier 39,
In the pocket 42, a ball 45 as a planetary rolling element is fitted so that spherical surfaces on the outer diameter side and the inner diameter side protrude.

Further, a through hole 46 is provided at the center of the ball 45, and a shaft 47 having both ends reduced in diameter is press-fitted and fixed in the through hole 46, and both ends of the shaft 47 protrude. This axis 47
Are axially supported by the ball bearings 43 and 44, and the ball 45 is positioned in the axial direction by step portions at both ends of the shaft 47. Due to this positioning, the ball 45 is kept out of contact with the inner peripheral surface of the pocket.

The ball 45 is interposed in a press-contact state between the concave raceway groove 48 of the second rotating shaft 38 and the annular groove formed by the pair of two ring bodies 33 and 34. By the way, the wide annular body 33 is formed by the elastic force of a spring washer 49 interposed between the end surface of the wide annular body 33 and the side wall 31a along the radial direction of the housing 31.
And the clearance between the other annular body 34 is adjusted in the axial direction,
The contact pressure between the tapered inner peripheral surfaces of the two annular bodies 33 and 34 and the ball 45 can be adjusted.

As described above, in the present embodiment, the ball 45 is integrally attached to the shaft 47, and the shaft 47 is supported by the ball bearings 43 and 44. It has been confirmed that a smooth ultra-high-speed rotation output can be achieved.

In addition, since the ball 45 is held by the carrier 39 so as not to be in contact with other members, there is no sliding contact portion as in the related art, so that abnormal heat generation does not occur with high-speed rotation. . Therefore, burn-in does not occur.

It should be noted that the present invention is not limited to the embodiments described above, and it is needless to say that various modified embodiments can be considered, though not described.

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

That is, a shaft is integrally attached to a ball as a planetary rolling element, and both ends of the shaft are pivotally supported by holes formed on both sides in the axial direction in the pocket of the carrier via ball bearings, so that the shaft is smooth. High-speed rotation can be realized.

Moreover, since the ball is held by the carrier so that it does not come into contact with other members, there is no sliding contact part as in the past, so there is no abnormal heat generation due to high speed rotation, and there is no burning. The result can be prevented.

[Brief description of the drawings]

1 and 2 relate to an embodiment of the present invention, and FIG.
The figure is a longitudinal sectional view of the upper half of the device of the present invention, and FIG. 2 is a right side view of FIG. 3 to 5 show two prior art examples, FIG. 3 is a longitudinal sectional view showing the upper half of the first conventional structure, and FIG. 4 is a longitudinal section showing the entire second conventional structure. Fig. 5 is the front view
FIG. 5 is a sectional view taken along line VV in FIG. 31 Fixed outer ring 35 First rotating shaft 38 Second rotating shaft 39 Carrier 41 Long hole of carrier 42 Carrier pocket 43,44 Ball bearing 45 Ball 46 Ball through hole 47… Shaft.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Keiji Suzuki, Inventor Keiji Suzuki, No. 2 Nagi, Nishinocho, Unagi, Minami-ku, Osaka-shi, Osaka Inside (72) Inventor Shiba ▲ Saki ▼ Shiro New work 1 in Takatsu-ku, Kawasaki-shi, Kanagawa No. 18-10 Maruwa Electric Co., Ltd. (56) References JP-A-51-59152 (JP, A) JP-A-52-32461 (JP, A) JP-A-59-29864 (JP, A) 60-138065 (JP, U) Jiko 46-35697 (JP, Y1) Jiko 51-41818 (JP, Y1)

Claims (1)

(57) [Claims] 1. A hollow cylindrical portion of a fixed outer ring, a first and a second rotating shafts coaxially opposed to each other, and a plurality of circumferentially arranged between the second rotating shaft and the fixed outer ring. A planetary rolling element provided at an axial end of the first rotating shaft,
A power transmission extending in a space between a rotating shaft and the fixed outer race, accommodating the planetary rolling element in a pocket penetrating in a radial direction, and a carrier for rotatably holding the planetary rolling element. In the device, the planetary rolling element is a ball, a shaft is press-fitted into the center of the ball in a penetrating state, and both ends of the shaft are inserted into holes formed continuously on both axial sides of the pocket of the carrier via ball bearings. A power transmission device characterized by being pivotally supported.