JPH09273547A - Multiple bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bear a multiple bearing in high speed, and also improve rigidity and safety, and reduce a cost by laminating a following step ball bearing mechanism composing of a following step outer wheel which is brought in contact with the outer side of a following step steel ball at least not less than one. SOLUTION: The ball bearing mechanism 2 of a base bottom step (a first step) consists of an inner wheel 21 inserted in the rotary shaft 10A of a motor, a steel ball 22 which is brought in contact with the inner wheel 21, a retainer 33 in which the steel ball 22 is arranged in a wrapping condition, and an outer wheel 34 which is brought in contact with the outer side of the steel ball 32. When the outer wheel 24 (namely the inner wheel 31) is rotated against the stationary outer wheel 34 and the inner wheel 21 formed integratedly with the rotary shaft 10A is rotated against the outer wheel 24, the inner wheel 21 against the outer wheel 34 is rotated with the speed of the sum of both speeds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple bearing that supports a rotary shaft while a hard sphere and a bearing are in point contact with each other.

[0002]

2. Description of the Related Art As is well known, a ball bearing (ball bearing) basically comprises an inner ring 100, a hard sphere 101, a retainer 102 and an outer ring 103, and is used in a wide variety of fields.

[0003]

When such a conventional ball bearing is rotated at a high speed, problems such as grease scattering and heat generation occur, and the limit is, for example, about 13000 rpm. Therefore, if ceramics are used, the rotation speed can be increased to tens of thousands of revolutions, but there is a drawback that the manufacturing cost increases. Further, non-contact type bearings such as air bearings and magnetic bearings which are suitable for higher speed rotation have been proposed and developed, but there are problems in terms of rigidity and stability.

In view of the above-mentioned circumstances, the present invention has an object to provide a multiple bearing suitable for high speed rotation and having good rigidity and stability at low cost.

[0005]

That is, the invention according to claim 1 is such that a rigid sphere contacting an inner ring to be inserted into a rotary shaft, a retainer arranging the rigid sphere in a wrapped state, and an outer ring contacting the outer side of the rigid sphere. The outer ring as the inner ring of the next stage outside the base ball bearing mechanism consisting of, and the next-stage hard sphere arranged so as to contact the inner ring of this next stage, and the next-stage hard sphere arranged in the enclosing state. At least one or more next-stage ball bearing mechanisms, each consisting of a retainer in the next stage and an outer ring in the next stage in contact with the outside of the hard sphere in the next stage, are layered.

According to the second aspect of the present invention, the ball bearing mechanism at each stage is arranged outside the base ball bearing mechanism in a zigzag pattern alternately left and right.

[0007]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. In this embodiment, the same parts as those of the prior art are denoted by the same reference numerals, and redundant description will be avoided. FIG. 1 shows a motor 10 to which a multiple bearing 1 according to the present invention is attached. As shown in FIG. 2, this multiple bearing 1 is provided outside a base stage (first stage) ball bearing mechanism 2. The ball bearing mechanism 3 is attached in one stage, and these ball bearing mechanisms are arranged straight (in the same plane) as shown in FIG.

The base stage (first stage) ball bearing mechanism 2 has an inner ring 21 to be inserted into the rotating shaft 10A of the motor 10, a rigid sphere 22 in contact with the inner ring 21, and the rigid sphere 22 in an enclosed state. It is composed of a retainer 23 and an outer ring 24 that contacts the outside of the hard sphere 22.

In the second stage ball bearing mechanism 3, the outer ring 24 also serves as the (second stage) inner ring 31 and this (second stage).
Hard ball 3 (second stage) arranged so as to contact the inner ring 31
2 and a retainer 33 (second stage) in which the (second stage) hard sphere 32 is arranged in a holding state, and is in contact with the outside of the (second stage) hard sphere 32 (second stage). ) The outer ring 34 and the outer ring 34.

Therefore, according to the multiple bearing 1 of the first embodiment, the outermost side, that is, the outer ring 34 is fixed to the housing 10B of the motor 10, and the innermost side, that is, the inner ring 22 is outside the rotary shaft 10A. It is configured to be inserted and rotate integrally. Therefore, the outer ring 24 (that is, the inner ring 31) rotates at the rotational speed V1 with respect to the stationary outer ring 34, and the inner ring 2 that is integral with the rotating shaft 10A of the motor 10 is used.
If 1 rotates at a rotational speed V2 (relatively) with respect to its outer ring 24, the inner ring 21 with respect to the outer ring 34 is substantially V1.
It can be rotated at a speed of + V2.

As a result, the inner or inner outer ring 24 (that is, the inner ring 31) rotates 10,000 times with respect to the outer ring 34 fixed to the housing 10B of the motor 10, and the inner ring 22 inside the outer ring 24 rotates. If it rotates 10,000 times relative to the inner ring 21, the rotating shaft 10A integrated with the inner ring 21
Means that the motor 10 is rotated twice as much as the housing 10B to rotate 20,000 times. Therefore, the multiple bearing 1 can be used to support the rotary shaft 10A of 20,000 rotations.

Next, another embodiment of the present invention will be described with reference to FIG.
Will be described with reference to. In the multiple bearing 1'of the second embodiment shown in FIG. 4, two-stage ball bearing mechanisms 3 ', 4'are attached to the outside of the (base) ball bearing mechanism 2'. As shown in FIG. 3, they are arranged in two straight lines (in the same plane).

These ball bearing mechanisms 2 ', 3', 4'are
The ball bearing mechanisms 3 ′ and 4 ′ are formed to have a bilaterally symmetrical shape, but in particular, a pair of left and right hard spheres 32 and 42 and retainers 33 and 43 that enclose the hard spheres 32 and 42 are provided. .

Therefore, according to this embodiment, since the two-stage ball bearing mechanism is laminated on the base bearing mechanism 2'and used, the rotary shaft 10A is rotated at the rotational speed added to the three convenient stages. The maximum rotation speed of each bearing mechanism is V
Then, the rotating shaft 10A at a rotation speed of 3V, which is almost three times as high as this.
Can be pivotally supported, and a laterally stable supporting action can be realized.

Next, still another embodiment of the present invention will be described with reference to FIG. In the multiple bearing of the third embodiment shown in FIG. 5, four stages of ball bearing mechanisms 3 ″, 4 ″, 5 ″ and 6 ″ are attached to the outside of the (base) ball bearing mechanism 2 ″. The bearing mechanisms are alternately arranged in a zigzag pattern as shown in Fig. 3. Each of these ball bearings has a hard ball and a retainer on one side.

Therefore, according to this embodiment, since the four-stage ball bearing mechanism is used by being laminated on the base bearing mechanism 2 ", the rotational speed obtained by adding the rotational speed of each bearing mechanism five times,
For example, when each stage is rotated at the rotation speed V, the rotation shaft 10A can be pivotally supported at the rotation speed of 5V as shown in FIG.

[0017]

As described above, according to the present invention, the ball bearing mechanism is laminated in multiple layers,
Since the shaft can be supported at a rotational speed that is the sum of the rotational speeds of each of these bearing mechanisms, it is suitable for bearings of high-speed rotating shafts, and at the same time provides a bearing with good rigidity and stability at low cost. can do.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a motor using a multiple bearing according to the present invention.

FIG. 2 is a plan view showing a multiple bearing according to the first embodiment.

FIG. 3 is a sectional view of the same.

FIG. 4 is a sectional view showing a multiple bearing according to a second embodiment.

FIG. 5 is a sectional view showing a multiple bearing according to a second embodiment.

FIG. 6 is an explanatory view showing the rotation speed of the multiple bearing shown in the second embodiment.

[Explanation of symbols]

 1, 1 ', 1 "multiple bearings 2, 2', 2" ball bearing mechanism 3, 3 ', 3 "ball bearing mechanism 4', 4", 5, 5'ball bearing mechanism

Claims (2)

[Claims] 1. A base ball bearing mechanism comprising: an inner ring to be inserted into a rotating shaft; a hard sphere in contact with the inner ring; a retainer arranging the hard sphere in a wrapped state; and an outer ring in contact with the outer side of the hard sphere. , The outer ring is the inner ring of the next stage, the next stage hard sphere arranged so as to contact the inner ring of the next stage, the retainer of the next stage arranged in a state of enclosing the hard sphere of the next stage, and the hard sphere of the next stage A multiple bearing characterized in that at least one or more next-stage ball bearing mechanisms consisting of a next-stage outer ring contacting the outside of the above are laminated. 2. The multiple bearing according to claim 1, wherein the ball bearing mechanisms of respective stages are alternately arranged on the outside of the base ball bearing mechanism in a zigzag pattern.