JPH11247851A - Composite bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the rotation in an inclined manner by fitting a sintered oil retaining bearing on either or each side of an inner ring or an outer ring of single row ball bearing. SOLUTION: A cylindrical sintered oil retaining bearing 4 is fitted into a space to be formed on a side part of an outer ring 2, a ball 3 and a retainer 5. The outside diameter of the sintered oil retaining bearing 4 is equal to the inside diameter of an outer ring sleeve 6, and the inside diameter is slightly larger than the outside diameter of an inner ring 1. Thus, the sintered oil retaining bearing 4 is fixedly fitted to the inside of the outer ring sleeve 6, and a small gap(g) is formed between the bearing and the outer circumferential surface of the inner ring 1. The gap(g) for suppressing the inclination is determined by the dimensions A and B so that the inclination does not exceed the allowable range. When the outer ring 2 side or the inner ring 1 side is inclined while a single composite bearing is in operation, one end of the B side of the oil sintered retaining bearing 4 is abutted on the A side of the inner ring 1 to prevent the shaft from being further inclined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing structure, and more particularly, to a composite bearing structure in which a single-row ball bearing and a cylindrical bearing are combined.

[0002]

2. Description of the Related Art Single-row ball bearings are frequently used in bearing mechanisms for rotating shafts, such as bearings for small motors, because of their simple structure and low cost. FIG. 17 shows a partial sectional view of a single-row ball bearing. In the single row ball bearing shown in FIG. 17, when one bearing 100 is used, the outer race 101 is
2 freely tilt as shown by θ ゜. Therefore, when a rotating body (not shown) such as a hub of a spindle motor is mounted on the outer ring 101, the rotating body
In contrast to this, an unstable rotation is performed while swinging in both axial and radial directions.

Further, the outer ring 101 is fixed, and the inner ring 10
For example, when a rotating body such as a rotating shaft of a spindle motor is mounted on the rotating body 3, the rotating body also performs unstable rotation on the outer ring 101 while swinging in both axial and radial directions.

As shown in FIG. 18, in order to prevent the rotating body from swinging and rotating, the single row ball bearings 100 and 110 are connected by two.
As shown in FIG. 19, two single-row ball bearings 10 are mounted in order to further reduce rotational runout.
A spacer 120 is mounted between the pins 0 and 110, and the mounting interval between the ball bearings 100 and 110 is widened to prevent the rotating body from falling down and to obtain stable high-precision rotation.

[0005]

However, when the width of the rotating body is to be reduced in accordance with the trend of miniaturization of various devices, the dimension L in FIG. 18 and FIG.
Want to be as small as possible. Therefore, the spacer 120 cannot be interposed between the single-row ball bearings 100 and 110 as shown in FIG. C, and the minimum critical dimension for miniaturization is two single-row ball bearings as shown in FIG. Ball receiver 100,
This is a case in which 110 is used repeatedly. Further, if a minimum critical dimension is to be obtained, a specially thin double row ball receiver must be prepared. Even in the case of producing such a specially thin double-row ball bearing, the size of the two-row parallel balls is limited by the width limit which is decisive, and thus has a limit.

As a specific example of the trend toward miniaturization of equipment, a disk drive (FDD / HDD) of a magnetic storage device has recently been used.
The transformation to smaller and thinner is fast-moving, and the demand for smaller and thinner spindle motors is very strong. In order to respond to the demand for a smaller and thinner spindle motor, it is important how the width of the bearing can be reduced (thinned). In response to this requirement, at present, the above-mentioned two-row ball bearings and specially designed double-row ball bearings have been limited. For such a single-sided bearing of a spindle motor, it is desired to reduce the thickness of the motor as a single ball bearing. However, in this case, the rotational runout occurs as described above, which is not practical. Also, using two single-row ball bearings on one side of the bearing may hinder the cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described conventional disadvantages, and has as its object to use two single-row ball bearings while using one ball bearing in a bearing structure. It is an object of the present invention to provide a thin ball bearing structure which can prevent the rotation shake as in the case of the above, and is inexpensive.

[0008]

Means for Solving the Problems In order to achieve the object of the present invention as described above, the invention according to the claims of the present application provides the following means. That is, the object of the present invention is to use one single-row ball bearing, which is the minimum unit for using ball bearings, and to solve the drawback of the inner / outer ring tilting runout when using one single-row ball bearing. The oil-impregnated sintered bearings (or oil-free dry bearings, fluid bearings, etc.) are mounted on one or both sides of the inner or outer ring of a single-row ball bearing to prevent tilting and rotation.

According to the present invention, the radial load is mainly received by the ball, and when the outer / inner ring is about to swing and tilt, the sintered oil-impregnated bearing mounted on one or both sides of the inner ring or the outer ring passes through the gap. Inside the opponent
Slight contact with the outer ring to prevent tilting, and the contact mating surface is an ultra-precision finished surface because it is the inner and outer ring surfaces of the single-row ball bearing, and has a small friction loss against tilting load.

Further, all the thrust load is received by the ball. As described above, most of the radial load is received by the ball, all the thrust load is received by the ball, and the friction loss received by the sintering oil-impregnated bearing for preventing inclination is small. There is no significant effect. According to the present invention, it is possible to form a composite bearing having a function of preventing falling without significantly increasing the width dimension of the single-row ball bearing, and to provide a bearing having a minimum width.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described in detail with reference to the drawings. The basic configuration of the composite bearing according to the present invention is classified into the following two types. 1: a single-row ball bearing and a composite bearing with one (one side) sintered oil-impregnated bearing (hereinafter referred to as a single composite bearing) The details of this configuration will be described with reference to FIGS. 1 to 8. 1: A composite bearing with one single-row ball bearing and two (both sides) sintered oil-impregnated bearings (hereinafter referred to as a double composite bearing). The details of this configuration will be described with reference to FIGS.
Next, these general features will be described. -1. Single compound bearing: Since there is only one sintered oil-impregnated bearing on one side, it is advantageous in terms of production and cost, but is somewhat disadvantageous in terms of tilt accuracy over double. -2. Double composite bearing: Slightly disadvantageous in terms of production and cost due to two inclined oil-impregnated bearings on both sides, but it is more advantageous than a single with respect to inclination accuracy.

Next, the detailed configuration of each composite bearing will be described. -1. Single compound bearing As shown in FIG. 1, a single compound bearing is provided with a space on one outer side of an inner ring 1 having a width L required to keep the inclination of the shaft within an allowable range, and the width of half of the width L is reduced. The outer ring 2 is disposed, and a ball 3 is fitted into a groove provided outside the inner ring 1 and inside the outer ring 2. The ball 3 is held by a retainer 5 so as not to deviate from the ball groove. The inner ring 1 has a ball groove as described above, and the outer shape is integrally super-finished with high precision. Outside the outer ring 2, a metal outer ring sleeve 6 having a cylindrical shape having a width L is provided.
Is inlaid.

A cylindrical sintered oil-impregnated bearing 4 is fitted in a space formed on the side of the outer race 2, the ball 3, and the retainer 5. The outer diameter of the sintered oil-impregnated bearing 4 is equal to the inner diameter of the outer ring sleeve 6, and the inner diameter is slightly larger than the outer diameter of the inner ring 1. For this reason, the sintered oil-impregnated bearing 4 is fixedly fitted inside the outer ring sleeve 6 and
A small gap g is formed between the inner ring 1 and the outer peripheral surface. The gap g for suppressing the inclination is determined based on the dimensions A and B in FIG. 1 so that the inclination does not exceed the allowable range, and therefore requires extremely high precision in processing.

During the operation of the single composite bearing, if the outer ring 2 side or the inner ring 1 side is inclined, one end of the B surface of the sintered oil-impregnated bearing 4 and the A surface of the inner ring 1 come into contact, and the inclination of the shaft is further increased. It is to prevent. The magnitude of the inclination of the shaft can be determined by the size of the gap g for suppressing the inclination.
As mentioned above, this single composite bearing basically
A structure in which a gap g for suppressing inclination is provided on the inner ring 1 side,
FIGS. 3, 5, and 7 show structures having a similar structure.
Shown in The detailed structure of these will be described later.

The single composite bearing shown in FIG. 3 has a gap g for suppressing tilt and an inner ring 1 having a single composite bearing.
It is a structure provided on the side. The sintered oil-impregnated bearing 4 processed to the outer diameter C, the inner diameter B, and the width W is combined with a single row ball bearing composed of the inner ring 1, the outer ring 2, the ball 3, and the retainer 5, as shown in FIG. In addition, there is no outer ring sleeve, and the outer surface of the sintered oil-impregnated bearing 4 is attached to a mating body by bonding or fitting so as to maintain a gap g for suppressing inclination. In this embodiment, unlike the embodiment shown in FIG. 1, the outer ring sleeve 6 is not required, and the outer ring sleeve 6 can be directly incorporated into the mating body, which is advantageous in reducing the size in the radial direction.

FIG. 5 shows a single composite bearing.
This is a structure in which a single composite bearing and a gap g for suppressing inclination are provided on the inner ring 1 side. The sintered oil-impregnated bearing 4 is the inner ring 1,
Combined with a single-row ball bearing composed of the outer ring 2, the ball 3, and the retainer 5, the outer ring 2 has a stepped large-diameter portion F, and the sintered oil-impregnated bearing 4 has the stepped Large diameter F
In such a structure, the inner ring 1 and the outer ring end face are fitted or fixedly attached by bonding so as to maintain the gap g for suppressing inclination. In this embodiment, the sintered oil-impregnated bearing 4 constitutes a composite bearing fixed and integrated with the outer race 2, and has a feature that it is easy to use and handle.
It does not require an outer ring spacer, and has a feature that the radial dimension can be reduced in size and cost is advantageous. Also, the assembly accuracy is high.

The single composite bearing shown in FIG.
This is a structure in which a single composite bearing and a gap g for suppressing inclination are provided on the inner ring 1 side. The sintered oil-impregnated bearing 4 is the inner ring 1,
Combined with a single-row ball bearing composed of the outer ring 2, the ball 3, and the retainer 5, the sintered oil-impregnated bearing 4 is provided on the inner diameter portion G of the outer ring 2 to maintain a gap g for suppressing inclination at the inner ring side AB dimension. Thus, the structure is fitted or fixedly mounted with an adhesive. In this embodiment, a composite bearing in which a sintered oil-impregnated bearing 4 is fixed to and integrated with the outer ring 2 is formed on the bearing whose both the outer diameter of the inner ring 1 and the inner diameter of the outer ring 2 are processed to standard dimensions. It is easy to handle and easy to handle, and does not require an outer ring spacer, and does not require stepping of the outer ring. Also, the assembly accuracy is high.

In addition, as shown in FIG. 2, the single composite bearing is provided with a space on one outer side of the inner ring 1 having a width L necessary for keeping the inclination of the shaft within an allowable range, and is provided with a half of the width L. An outer ring 2 having a width of ????? is disposed, and a ball 3 is fitted into a ball groove provided outside the inner ring 1 and inside the outer ring 2. The ball 3 is held by a retainer 5 so as not to deviate from the ball groove. The inner ring 1 has a ball groove as described above, and the outer shape is integrally super-finished with high precision. A metal outer ring sleeve 6 having a cylindrical shape with a width L is fitted on the outer side of the outer ring 2.

A sintered oil-impregnated bearing 7 is arranged in a space formed on the side of the outer race 2, the ball 3, and the retainer 5. As shown in FIG. 2, the sintered oil-impregnated bearing 7 has an outer diameter smaller than an inner diameter of the outer ring sleeve 6 and an inner diameter equal to the outer diameter of the inner ring 1. For this reason, the sintered oil-impregnated bearing 7 is fixedly fitted to the outside of the inner ring 1, and a small gap g is formed between the sintered oil-impregnated bearing 7 and the inner peripheral surface of the outer ring 2. The gap g for suppressing the inclination is determined by the dimensions C and D in FIG. 2 so that the inclination does not exceed the allowable range, and therefore requires extremely high precision in processing.

During the operation of the single composite bearing, when the outer ring 2 or the inner ring 1 is inclined, one end of the C surface of the sintered oil-impregnated bearing 7 and the D surface of the outer ring sleeve 6 come into contact with each other. This is to prevent inclination. The magnitude of the inclination of the shaft can be determined by the size of the gap g for suppressing the inclination. As described above, this single composite bearing basically has a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side, and a structure similar to this is shown in FIGS. FIG. The detailed structure of these will be described later.

FIG. 4 shows a single composite bearing.
This is a structure in which a gap g for suppressing inclination is provided in the outer ring 2. Outer diameter C and width l to be the specified gap g for inclination suppression
The structure is such that a sintered oil-impregnated bearing 7 having dimensions is incorporated into the inner race 1 by bonding or press-fitting so as to keep a gap S at the end face of the outer race 2. The outer ring 2 is incorporated into the inner diameter E of the mating body by bonding or fitting pressure, and forms a gap g for suppressing inclination between the outer ring 2 and the mating inner diameter E. The composite bearing having these structures shown in FIGS. 3 and 4 is advantageous for reducing the size in the radial direction.

FIG. 6 shows a single composite bearing.
This is a structure in which a gap g for suppressing inclination is provided on the outer ring 2 side. In a single-row ball bearing composed of an inner ring 1, an outer ring 2, a ball 3, and a retainer 5, the outer ring 2 has a stepped large-diameter portion F, and the sintered oil-impregnated bearing 7 Large diameter F
The inner ring 1 is fitted or fixed to the inner ring 1 with an adhesive so as to maintain a gap g for suppressing inclination of the outer ring and the outer ring and to provide a gap S at the outer ring end face. This structure constitutes a composite bearing in which the sintered oil-impregnated bearing 7 is fixed and integrated with the inner ring 1, has a feature of being easy to use and handle, and does not require an outer ring spacer, and has a radial dimension. It is characterized in that it is smaller and has a cost advantage. Also, the assembly accuracy is high.

FIG. 8 shows a single composite bearing.
This is a structure in which a gap g for suppressing inclination is provided on the outer ring 2 side. In a single-row ball bearing composed of the inner ring 1, the outer ring 2, the ball 3, and the retainer 5, a gap for suppressing inclination between the inner diameter portion G of the outer ring 2 and the outer diameter portion C of the sintered oil-impregnated bearing 7. The structure is such that the sintered oil-impregnated bearing 7 is fitted into the inner race 1 or fixedly attached with an adhesive so as to generate g. This structure has a composite bearing in which the sintered oil-impregnated bearing 7 is fixed and integrated with the inner ring 1 on the bearing whose both the outer diameter of the inner ring 1 and the inner diameter of the outer ring 2 are processed to the standard size, and is easy to use and handle. Features and does not require outer ring spacers,
In addition, the outer ring is not required to be stepped, and is characterized in that it has the smallest radial dimension and is cost-effective. Also, the degree of assembly is high.

-2. Double compound bearing As shown in FIG. 9, the double compound bearing is provided with an outer ring 2 having the width L at an interval outside the inner ring 1 having a width L necessary to keep the inclination of the shaft within an allowable range. And
A ball 5 is fitted into a ball groove provided at the center of the outside of the inner ring 1 and the inside of the outer ring 2. The ball 5 is held by the retainer 5 so as not to deviate from the ball groove. The inner ring 1 has a ball groove as described above, and the outer shape is integrally super-finished with high precision.

Two semi-sintered oil-impregnated bearings 8 and 9 having a width l are fitted in spaces on both sides of the ball 3 and between the inner ring 1 and the outer ring 2. The outer diameter of the semi-sintered oil-impregnated bearings 8 and 9 is equal to the inner diameter of the outer ring 2, and the inner diameter is slightly larger than the outer diameter of the inner ring 1. For this reason, the semi-sintered oil-impregnated bearing 8,
9 is fixedly fitted inside the outer ring 2 and has a small gap g between the outer ring 2 and the inner ring 1. The gap g for suppressing the inclination is determined based on the dimensions A and B in FIG. 9 so that the inclination does not exceed the allowable range.
Therefore, processing requires very high precision.

During the operation of this double composite bearing,
When the outer ring 2 side or the inner ring 1 side is inclined, one end of the B surface of the semi-sintered oil-impregnated bearings 8 and 9 mounted on both sides abuts the A surface of the inner ring 1 to prevent the shaft from further tilting. Things. The magnitude of the inclination of the shaft is determined by the gap g
Can be determined by the size of As described above, this single composite bearing basically has a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side, and a structure similar to this is shown in FIGS. FIG. The detailed structure of these will be described later.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side. The two sintered oil-impregnated bearings 8, 9 machined to the outer diameter C, the inner diameter B, and the width L, respectively, are connected to the outer race 2 of the single row ball bearing composed of the inner ring 1, the outer ring 2, the ball 3, and the retainer 5. This is a set configuration in which a gap g for suppressing inclination is formed on the inner ring 1 side by being sandwiched and fitted into a partner body. In this case, the other body can be designed in a free shape, and at the same time, the outer ring sleeve 6 can be designed.
Can be incorporated directly into the opponent's body without the need for
This is also advantageous for reducing the size in the radial direction.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side. The two sintered oil-impregnated bearings 8 and 9 processed to the outer diameter C, the inner diameter B and the width l are respectively combined with the outer race 2 of the single-row ball bearing composed of the inner ring 1, the outer ring 2, the ball 3 and the retainer 5. The outer ring sleeve 6 is sandwiched and fitted or adhered to the inner diameter portion of the outer ring sleeve 6, so that a gap g for suppressing inclination with the outer ring sleeve 6 is formed. Although the outer diameter of the composite bearing is large, it is easy to handle and assemble because of the integrated structure.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side. Two sintered oil-impregnated bearings 8 and 9 each having an outer diameter F, an inner diameter B and a width l are processed into an outer ring 2 of a single-row ball bearing composed of an inner ring 1, an outer ring 2, a ball 3 and a retainer 5. It is fitted into the large diameter F portion from both sides so as to form a gap g on the inner ring 1 side for suppressing inclination, and has an integrated structure. In this embodiment, two sintered oil-impregnated bearings 8 and 9 are directly mounted on and integrated with the outer ring 2 without the need for an outer ring sleeve, so that it is compact and easy to use, and is advantageous for downsizing in the radial direction. .

As shown in FIG. 10, the double composite bearing is provided with an outer ring 2 having the width L by providing a space outside the inner ring 1 having a width L necessary to keep the inclination of the shaft within an allowable range. Are arranged, outside the inner ring 1 and inside the outer ring 2,
The ball 5 is fitted in a ball groove provided at the center thereof. The ball 5 is held by the retainer 5 so as not to deviate from the ball groove. The inner ring 1 has a ball groove as described above, and the outer shape is integrally super-finished with high precision.

Two semi-sintered oil-impregnated bearings 10 and 11 having a width 1 are fitted in spaces on both sides of the ball 3 and between the inner ring 1 and the outer ring 2. The outer diameter of the semi-sintered oil-impregnated bearings 10 and 11 is slightly smaller than the inner diameter of the outer ring 2, and the inner diameter is equal to the outer diameter of the inner ring 1. Therefore, the semi-sintered oil-impregnated bearings 10 and 11 are fixedly fitted to the outside of the inner ring 1, and a small gap g is formed between the semi-sintered oil-impregnated bearings 10 and 11 and the inner peripheral surface of the outer ring 1. The gap g for suppressing the inclination is determined by the dimensions C and G in FIG. 10 so that the inclination does not exceed the allowable range, and therefore requires extremely high precision in processing.

During the operation of this double composite bearing,
When the outer ring 2 side or the inner ring 1 side is inclined, one end of the C surface of the semi-sintered oil-impregnated bearings 10 and 11 mounted on both sides abuts on the G surface of the outer ring 2 to prevent further inclination of the shaft. Things. The magnitude of the inclination of the shaft can be determined by the size of the gap g for suppressing the inclination. As described above, this double composite bearing basically has a structure in which a gap g for suppressing inclination is provided on the inner ring 1 side, and a structure similar to this is shown in FIGS. This is shown in FIG. The detailed structure of these will be described later.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the outer ring 2 side. Two sintered oil-impregnated bearings 10, 11 each having an outer diameter C, an inner diameter B, and a width L, each having a clearance with the outer ring of a single-row ball bearing composed of an inner ring 1, an outer ring 2, a ball 3, and a retainer 5. This structure is such that the outer ring 2 is sandwiched between the inner ring 1 and the inner ring 1 so as to maintain S, so that a gap g for suppressing the inclination with the counterpart body is formed. In this case, handling and assembling properties are easy because they are not set but integrated as in the example of FIG. Further, the mating body can be designed in a free shape, and at the same time, the outer ring sleeve is not required and the mating body can be directly incorporated into the mating body, which is advantageous in reducing the size in the radial direction.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the outer ring side. Two sintered oil-impregnated bearings each having an outer diameter C, an inner diameter B, and a width l are formed into a gap S with an outer ring 2 of a single-row ball bearing composed of an inner ring 1, an outer ring 2, a ball 3, and a retainer 6. The inner ring 1 is fitted or adhered to the outer diameter portion of the inner ring 1 with the outer ring 2 interposed therebetween so as to maintain a gap g for suppressing inclination with the outer ring sleeve 6. Although the outer diameter of the composite bearing is large, it is easy to handle and assemble because of the integrated structure.

The double composite bearing shown in FIG.
This is a structure in which a gap g for suppressing inclination is provided on the outer ring 2 side. Outer ring 2 of a single row ball bearing comprising two sintered oil-impregnated bearings 10, 11 each having an outer diameter C, an inner diameter B, and a width l, each including an inner ring 1, an outer ring 2, a ball 3, and a retainer 5.
The outer ring portion is inserted or bonded to the inner ring 1 from both sides so as to maintain the gap S with the stepped end surface of the outer ring 2 so that the stepped large-diameter portion F surface of the outer ring 2 and the gap g for suppressing inclination are formed. It has an integrated structure. In this embodiment, since the two sintered oil-impregnated bearings 10 and 11 are directly assembled and integrated with the outer ring 2 without the need for the outer ring sleeve 6, it is compact and easy to use, which is advantageous for downsizing in the radial direction. is there.

While the present invention has been described with reference to the above-described embodiment, for example, the inner ring 2 may be applied to a solid rotation / stop shaft, or a dry bearing (ceramic-free) may be used instead of a sintered oil-impregnated bearing.・ Synthetic resin materials, other materials used as solid bearings, etc.), fluid bearing structures and magnetic bearing structures, and a seal plate (seal mechanism) attached to the composite bearing. Various modifications and applications are possible within the scope, and these modifications and applications are not excluded from the scope of the present invention.

[0037]

As described in detail above, the present invention provides
In order to use one single-row ball bearing, which is the minimum unit for bearing use, and to solve the problem of inner / outer ring tilt runout when using one single-row ball bearing, a sintered oil-impregnated bearing for preventing tilting is used. It is mounted on one or both sides of the inner or outer ring of a single-row ball bearing to prevent tilting and rotation, so that the bearing shaft can be stably and supported in the same way as when at least two conventional ball bearings are juxtaposed. In addition to being able to bear thinly in the axial direction,
Since only one ball bearing is used, it can be provided at a lower cost than a conventional bearing structure.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a single composite bearing of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the single composite bearing of the present invention.

FIG. 3 is a cross-sectional view showing a third embodiment of the single composite bearing of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the single composite bearing of the present invention.

FIG. 5 is a sectional view showing a fifth embodiment of the single composite bearing of the present invention.

FIG. 6 is a sectional view showing a sixth embodiment of the single composite bearing of the present invention.

FIG. 7 is a sectional view showing a seventh embodiment of the single composite bearing of the present invention.

FIG. 8 is a sectional view showing an eighth embodiment of the single composite bearing of the present invention.

FIG. 9 is a cross-sectional view showing a first embodiment of a double composite bearing of the present invention.

FIG. 10 is a cross-sectional view showing a second embodiment of the double composite bearing of the present invention.

FIG. 11 is a sectional view showing a third embodiment of the double composite bearing of the present invention.

FIG. 12 is a cross-sectional view showing a fourth embodiment of the double composite bearing of the present invention.

FIG. 13 is a cross-sectional view showing a fifth embodiment of the double composite bearing of the present invention.

FIG. 14 is a cross-sectional view showing a sixth embodiment of the double composite bearing of the present invention.

FIG. 15 is a cross-sectional view showing a seventh embodiment of the double composite bearing of the present invention.

FIG. 16 is a sectional view showing an eighth embodiment of the double composite bearing of the present invention.

FIG. 17 is a sectional view of a conventional ball bearing.

FIG. 18 is a cross-sectional view showing an example in which two conventional ball bearings are arranged.

FIG. 19 is a cross-sectional view showing an example in which spacers are arranged between conventional ball bearings.

[Explanation of symbols]

 g: Gap for tilt control s: Gap 1 ... Inner ring 2 ... Outer ring 3 ... Ball 4 ... Sintered oil impregnated bearing 5 ····· Retainer 6 ···· Outer ring sleeve 7 ···· Sintered oil impregnated bearing 8 ···· Semi-sintered oil impregnated bearing 9 ···· Semi-sintered oil impregnated bearing 100 ···· Single-row ball bearing 101 ... Outer ring 102 ... Ball 103 ... Inner ring 110 ... Single-row ball bearing 120 ... Spacer

Claims (16)

[Claims] 1. A composite bearing in which a single-row ball bearing and a cylindrical bearing are combined, wherein an inner ring and an outer ring which are respectively fixed to one of the opposing bodies of the bearing portion and which are coaxially arranged at relatively spaced intervals; A ball rotatably fitted in a ball groove provided on the opposing surface of the inner ring and the outer ring; and a cylindrical shape disposed at least to the side of the ball among the outer ring, the inner ring and the ball. At the same time, one of the inner surface and the outer surface is fixed to any one of the bearings of the bearing portion, and the other surface defines an allowable range in which the other ring of the bearing portion and the inner ring and the outer ring are inclined. And a friction bearing facing each other while maintaining a gap limited to a value. 2. A composite bearing in which a single-row ball bearing and a cylindrical bearing are combined, wherein an outer ring and an inner ring which are respectively fixed to one of the opposing bodies of the bearing portion and are coaxially arranged at relatively spaced intervals; A ball rotatably fitted in a ball groove provided on the opposing surface of the inner ring and the outer ring; and a cylindrical shape disposed at least to the side of the ball among the outer ring, the inner ring and the ball. At the same time, the outer surface is fixed to the bearing portion, and the inner surface is opposed to the other mating body of the bearing portion, and the friction bearing is opposed to the inner ring and the outer ring while maintaining a gap enough to limit the allowable range in which the inner ring and the outer ring are inclined to a predetermined value. A composite bearing comprising: 3. The composite bearing according to claim 2, wherein the bearing portion to which the outer surface of the friction bearing is fixed is an outer ring sleeve fitted to the outer ring. 4. The composite bearing according to claim 2, wherein the bearing portion to which the outer surface of the friction bearing is fixed is an extension of the outer race. 5. A composite bearing in which a single-row ball bearing and a cylindrical bearing are combined, wherein an outer ring and an inner ring are fixed to one of the opposing members of the bearing portion and are coaxially arranged at relatively spaced intervals. A ball rotatably fitted in a ball groove provided on the opposing surface of the inner ring and the outer ring; and a cylindrical shape disposed at least to the side of the ball among the outer ring, the inner ring and the ball. At the same time, a friction bearing whose inner surface is fixed to the bearing portion, and whose outer surface faces the other mating portion of the bearing portion, maintaining a gap enough to limit the allowable range in which the inner ring and the outer ring are inclined to a predetermined value. A composite bearing comprising: 6. The composite bearing according to claim 5, wherein the bearing portion on which the outer surface of the friction bearing faces at a distance is an outer ring sleeve fitted to the outer ring. 7. The composite bearing according to claim 5, wherein the bearing portion on which the outer surface of the friction bearing faces at an interval is an extension of the outer race. 8. A composite bearing in which a single-row ball bearing and a cylindrical bearing are combined, wherein an inner ring and an outer ring which are fixed to one of the mating members of the bearing portion and are coaxially arranged at relatively spaced intervals; A ball rotatably fitted in a ball groove provided at a center portion of the opposing surfaces of the inner ring and the outer ring; and a cylindrical member disposed at least on both sides of the outer ring, the inner ring and the ball on both sides of the ball. The outer surface is fixed to one of the mating members of the bearing portion, and the inner surface of the inner member and the other member of the bearing portion have a clearance that limits the allowable range in which the inner ring and the outer ring are inclined to a predetermined value. And a friction bearing holding and facing the composite bearing. 9. The composite bearing according to claim 8, wherein the bearing portion to which the outer surface of the friction bearing is fixed is an outer ring sleeve fitted to the outer ring. 10. The composite bearing according to claim 8, wherein the bearing portion to which the outer surface of the friction bearing is fixed is an extension of the outer race. 11. A composite bearing in which a single-row ball bearing and a cylindrical bearing are combined, comprising: an inner ring and an outer ring which are fixed to one of the opposing bodies of the bearing portion and are coaxially arranged at relatively spaced intervals; A ball rotatably fitted in a ball groove provided at a center portion of the opposing surfaces of the inner ring and the outer ring; and a cylindrical member disposed at least on both sides of the outer ring, the inner ring and the ball on both sides of the ball. The inner surface is fixed to one of the bearings of the bearing portion, and the outer surface of the bearing is limited to a predetermined value in a tolerance range in which the inner ring and the outer ring are inclined with the other partner of the bearing portion. And a friction bearing that faces the composite bearing. 12. The composite bearing according to claim 11, wherein the bearing portion on which the outer surface of the friction bearing faces at a distance is an outer ring sleeve fitted to the outer ring. 13. The composite bearing according to claim 11, wherein the bearing portion on which the outer surface of the friction bearing faces at a distance is an extension of the outer race. 14. The friction bearing according to claim 1, 2 or 5, wherein the friction bearing is a bearing oil-impregnated bearing.
A composite bearing according to claim 8 or claim 11. 15. The composite bearing according to claim 1, wherein said friction bearing is an oil-free dry bearing. 16. The composite bearing according to claim 1, wherein said friction bearing is a fluid bearing.