JPS6272945A - Elliptic raceway rolling bearing - Google Patents

Abstract

PURPOSE:To reduce friction torque at the time of rotation as well as to decrease the extent of wear, by installing a pocket part in a retainer holding a ball rolling between both inner and outer rings and lessening a degree of play in the retainer at a short race position of a rolling bearing. CONSTITUTION:With rotation of an inner ring 4a, a rolling position of a ball 4c comes to move as repeating a long race position and a short race position alternately. At this time, a narrow part 4f of a pocket 4e in a retainer 4d comes close to the ball 4c, restricting this ball 4c. Accordingly, the retainer 4d will not come into contact with the inner surface of an outer ring 4b on the short race,and further the inside surface rotates without contacting an outer surface of the inner ring 4a. Next, the ball 4c on the long race comes into a state of being floated from the pocket 4e because the retainer 4d is true roundness in form. Therefore, the retainer 4d is regulated of its play in both long and short race directions, thus it is in no case contacted with both inner and outer rings.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in an elliptical orbit rolling bearing suitable for use as a reduction gear or cam device as a flexible mesh power transmission device.

[Technical background of the invention and its problems]

Conventionally, as a mechanism using this virtue, a flexible 7 flex spline having many teeth on the outer periphery is solidly layered on the outside of an elliptical orbit rolling bearing fixed to the drive shaft, and this flex spline is A perfectly circular bouquet elasge line has a large number of teeth on the inner periphery so as to mesh with the teeth of the.

It is designed so that a considerably large deceleration can be obtained in correlation with the number of meshing teeth of each of the teeth, and it is structurally light: 1 it-
However, while the inner and outer rings of an elliptical orbit roller are elliptical in the shape of a p-bearing, the retainer has perfect circular rigidity.・When the rolling position of the balls formed between the outer rings reaches the longest position K from the center position of the bearing (hereinafter referred to as the long axis position), the inner surface of the retainer approaches the outer surface of the inner ring, and vice versa. When the retainer reaches the shortest position from the center of the bearing (hereinafter referred to as the short axis position), the outer surface of the retainer approaches the outer and inner surfaces, and the retainer itself has many points between the inner and outer surfaces. Although the retainer retains the balls, there is considerable dimensional play between the inner and outer rings, and as the retainer moves due to the transfer of the balls, the retainer and the inner and outer rings come into contact with each other at the approaching portion. The frictional contact between the and each part is part of the #friction torque as an elliptical orbit rolling bearing.

Furthermore, if such frictional parts do not slide well, considerable friction occurs and abrasion powder is generated, which impedes normal rotation of the bearing. Sometimes, in environments where lubrication with oil or grease cannot be performed, the effects of frictional torque and abrasion powder generated by *m contact between the retainer and the valleys are large and may cause problems in terms of performance.

[Purpose of the invention] The present invention has been made in view of the above points.

The frictional contact between the retainer and the inside and outside is minimized to reduce the single vibration torque and wear during rotation of the elliptical orbit rolling bearing, thereby eliminating the above-mentioned drawbacks of the conventional bearing.

[Summary of the invention]

That is, by restraining the balls rolling between the circle and the outer ring at the so-called short axis position by the pocket portion that holds the balls, the play of the retainer is reduced, and 4! This provides a high-performance elliptical orbit rolling bearing that eliminates frictional contact with various parts.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention in which the present invention is used as a flexible mesh power transmission device will be described with reference to the drawings.
1), a wave generator consisting of a hub (2), seven lugs (3), and a packed circular orbit rolling bearing ((1) (hereinafter referred to as the bearing) is fixed to the bearing.
Elliptical rigid inner ring (4a) and this inner ring (4a)
A flexible outer ring (4b) having a similar shape to the above, a large number of balls (4C) arranged between the inner and outer rings (4a) and (4b), and these balls (4c)...・
It consists of a retainer (4d) that holds the. The retainer (4d) is a rigid one having a perfect circular shape, and has a bulge 7 for holding each of the balls (4c) in a fixed position.
)(4e)... are provided. This pocket (4e)
ff, when the rolling position of the ball (4c)... formed between the inner and outer rings (4a) and (4b) comes to the bearing (the shortest position from the center of force position (hereinafter referred to as short axis position) , a pinched portion (4f) is formed to restrain the ball (4c) held in this pocket (4e). That is,
This pinched portion (4f) is formed because when the ball (4C) is in the short axis position, the pocket (4e) of the retainer (4d) comes into contact with the ball (4c) and restricts the movement of the retainer (4d) itself. It is a book that is formed smaller than the diameter of the ball (4C).

When the ball (4c) reaches the long axis position, the ball (4c) is formed to have a trumpet-shaped opening in the outer circumferential direction that is at least larger than the size of the ball so that the ball (4c) can separate from the pinched portion (4f). It is something.

The outer m (4b) of the bearing (4) is in frictional contact with the inner periphery of the opening of a cup-shaped 7-rex grain (5) solidly layered on the outside thereof. The plug (3) has a suitable elliptical shape and has rigidity. The 7-rex spline (5) has M flexibility, and a large number of teeth (5a) are formed around the outer periphery of the opening as shown in FIG. On the outer periphery of the flexspline (5), there is a buculus grain (6) formed on the inner periphery with a large number of teeth (6a).
It is designed to mesh with... The teeth (5a) formed on the flex spline (5) and the ff1 (6a) formed on the circular spline (6) are as follows:
They are provided at the same pitch, and the number of teeth on the circular spline (6) side is slightly greater than the number of teeth on the 7-rex spline (5) side.

Since it is configured in this way, the drive shaft (1
) rotates, and at the same time the inner ring (4a) rotates, the hub (2
), rotates through the plug (3). This inner ring (4a)
will rotate while remaining in the shape of a circle.

This rotation causes it to go out! ! (4b) is the ball (4c)...
At the same time, the opening of the 7 lex grain (5) also becomes K so that the 7 lex grain (5) has the same MK flexural undulation.
The teeth (5a) and the teeth (6a) of the buculus spline (6) mesh with each other.

At this time, due to the difference in the number of strokes between the two teeth, if the inner ring (4a) rotates once with the 7 lex spline (5) fixed, the buculus grain (6) will rotate between the 7 lex splines (5) and the inner ring (4a). On the other hand, the amount of force is slightly reversed in the direction of rotation of the inner ring (4a) according to the tooth number ratio.

Next, we will discuss the operation.

As the inner M (4a) is driven by transmission, the outer ring (4b) simultaneously changes its direction along the rectangular direction of the inner ring (4a) via the balls (4c). The ball between the inner and outer rings (4a) and (4b) (
4c) The rolling position of... starts to move repeatedly between the moxibustion axis position and the short axis position. At this point, the retainer (4d) is attached to the ball (4C) at the short axis position.
The small part (4f) of the pocket (4e) is the ball (4C)
As the ball approaches the surface of the ball, this ball (4C) will be restrained.

In other words, the retainer (4d) is restrained by the balls (4C), and the so-called dimensional play of the retainer (4d) in the major axis direction and the minor axis direction is small.

Therefore, the retainer (4d) has an outer ring (
It rotates without contacting the inner surface of the inner ring (4b) and without the inner surface touching the inner ring (4a) outwardly.

Here, the ball (4C) on the long sleeve is in a state floating from the pocket (4e) of the retainer (4d), as shown in FIG. In other words, while the retainer (4d) is a perfect circle, the same value (4a) is in a +A round shape, so the retainer (4d)'s bulge) (4e) is a ball (
This is because the rolling locus of 4C)... is shifted to the inner side (4a).

[Young red of invention]

As described above, the present invention provides a bearing including a large number of balls interposed between a circular outer ring and an inner ring, and a perfectly circular retainer that holds the balls, and this retainer holds each ball. A cup-shaped pocket larger than the ball is formed, and when this pocket reaches the short axis position fK of the bearing,
In order to restrain the ball being held, a small part with a size smaller than the diameter of the ball is used.

The retainer is designed so that the small part of the pocket touches the ball on the short axis.

The retainer restricts dimensional play in the long axis direction and the narrow axis direction of the bearing. Therefore,
Since the retainer does not come into contact with the inner or outer ring, it can reduce the single vibration torque and wear when the bearing rotates, and is suitable for use in environments where lubrication with oil or grease is not possible. This is suitable.

[Other embodiments of the invention]

The present invention is not limited to the above structure, and the pocket provided in the retainer has a tapered surface (4e) at a predetermined angle so as to open toward the outer circumference as shown in FIG.
). In this case, since the pocket is easy to mold and the inner surface of the pocket relative to the ball is flat, contact with the ball can be made relatively smooth.

Alternatively, as shown in FIG. 5(a), it may be formed by tapered surfaces 4e/4e' having different angles. In this case, it is relatively easy to process the pockets, and when the retainer is keyed on the long axis, it can be easily released from the retainer, and as in the above embodiment, the retainer's ability to restrain the balls is also improved. It is effective.

Note that the tapered surface may have three or more tapered surfaces at different angles. Furthermore, the present invention is not only used as a speed reduction device as in the above-mentioned embodiments, but also
Since the specific point changes its position from short axis to long axis to short axis, it goes without saying that this can be used as a cam device or bong device.

[Brief explanation of drawings]

The drawings are diagrams showing the present invention, and FIG. 1 is a front view of the flexible mesh power transmission 4Ii, FIG. 2 is a partially vertical side view of the flexible mesh power transmission device, and FIG. 3 is a diagram showing the bearing flexspline and Front view showing interaction with circular spline, No. 4
The figure is an enlarged view of part A in Figure 1, and Figures 5 (a) and (c2) are views showing other embodiments corresponding to Figure 4. Bearing, (4a)...Inner ring, (4b)...Outer ring, (4C)...Ball, (4d
)... Retainer, (4e)...Boken), (4f)
...Pinch part, (5) ...7 Rex spline, (6)
...Circular spline. Agent: Patent attorney Noriyuki Ken Yudo Patent attorney: Kikuo Takehana 1. Stomach boil 2.

Claims (2)

[Claims] (1) A large number of balls are interposed between an elliptical outer ring and an inner ring, and a perfectly circular retainer is provided between the outer ring and the inner ring to hold the balls, and this retainer holds each ball. A cup-shaped pocket larger than the ball is formed in this pocket, and a pincher smaller than the diameter of the ball is formed in this pocket to restrain the ball held in the pocket when the ball is at the minor axis position in the outer ring and the inner ring. An elliptical orbit rolling bearing characterized by having small parts. (2) The elliptical orbit rolling bearing according to claim 1, wherein the pocket is formed by a tapered surface having a predetermined angle or by two or more tapered surfaces having different angles.