JPH08152021A - Submerged bearing - Google Patents

Abstract

PURPOSE: To provide a water-injectionless starting submerged bearing which is constituted in such a manner that the bearing is durable against a deviated load by a spindle and during a work to insert the spindle, the same degree of prudence as that of a conventional type is sufficient. CONSTITUTION: The outer periphery of a cylindrical resilient body 10 is covered with a metallic cylinder body 12. A plurality bearing slide pieces 14, 14... peripherally divided and axially integrally formed and rigid and abundant in wear resistance and formed of ceramic are disposed in the cylindrical resilient body 10 at equal intervals in a peripheral direction. Further, U-grooves 10b, 10b,... in an axial direction are formed in the inner periphery of the cylindrical resilient body 10 and in respective parts between the adjoining bearing slide pieces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a submersible bearing which supports a main shaft such as a pump for pumping water and can start without water injection.

[0002]

2. Description of the Related Art As an example of a submersible bearing capable of starting without water injection, a cylindrical ceramic is used as a sliding member, and the sliding member is bonded to a metal cylinder through an elastic body. . This submersible bearing has a problem that abnormal wear and cracks are likely to occur in the sliding member against an unbalanced load due to the main shaft.

Therefore, as a technique for improving the above-mentioned submersible bearing, a technique disclosed in Japanese Patent Laid-Open No. 5-126138 has been proposed. In this submersible bearing, a hard sliding piece made of a hard material such as ceramic, which is divided into a circumferential direction and an axial direction, is provided on the inner circumferential surface of a tubular cushioning material such as rubber whose outer circumference is covered with a metal shell. It is arranged. Since the hard sliding pieces are divided in both the circumferential direction and the axial direction and placed independently, the degree of freedom is increased. By changing it, it is possible to disperse and bear the load, and it is possible to obtain a bearing that is strong against an unbalanced load.

[0004]

In the technique described in the above publication, with respect to the unbalanced load of the inserted spindle,
The greater the degree of freedom of the hard sliding piece, the stronger the effect. However, ceramic is brittle and its impact force is extremely weak.When inserting the spindle into such a bearing, the hard sliding piece is also divided in the axial direction, so the tip of the spindle is the end surface of the hard sliding piece. There is a high possibility that impact force will be applied to the hard sliding piece, which may break the hard sliding piece. Therefore, when inserting and pulling out the spindle, extremely careful handling is required, and the workability is poor.

The present invention has been made in view of the circumstances of the above-mentioned technology, and is strong against an eccentric load by the main spindle, and when inserting the main spindle, the degree of caution is the same as that using a conventional ceramic. The object is to provide a submersible bearing that is sufficient.

[0006]

In order to achieve the above object, the submersible bearing of the present invention has a cylindrical elastic body whose outer periphery is covered with a metal cylindrical body, which is divided in the circumferential direction and is integrally hard in the axial direction. And a plurality of bearing sliding pieces made of ceramics with high wear resistance are arranged at equal intervals in the circumferential direction inside the cylindrical elastic body, and the inner circumference of the cylindrical elastic body is arranged. Thus, the bearing sliding piece is formed by engraving an axial groove in a space.

A bearing protection piece made of a resin having a higher elasticity than that of the ceramic is disposed in close contact with the end surface of the bearing sliding piece on at least one side where the main shaft is inserted in the axial direction. The inner diameter formed by the bearing protection piece may be the same as the inner diameter formed by the bearing sliding piece.

[0008]

[Operation] Since a groove is formed in the axial direction at the inner peripheral portion of the cylindrical elastic body in which the bearing sliding pieces are arranged at a certain distance, a cylinder is formed by the peripheral surface of the groove. The area of the free surface of the elastic body is enlarged, and the cylindrical elastic body is elastically deformed accordingly. Therefore, the cylindrical elastic body is easily elastically deformed with respect to the unbalanced load by the main shaft, and the plurality of bearing sliding pieces that receive the load can appropriately abut on the main shaft to disperse and bear the load. Moreover, the bearing sliding piece is not divided in the axial direction but is integral, and when inserting the main shaft, careful work is required when the tip end surface passes through the end of the bearing sliding piece. However, it is similar to the conventional submerged bearing using a cylindrical ceramic.

If a bearing protection piece is provided at one end of the bearing sliding piece into which the main shaft is inserted, an impact force when inserting the main shaft is applied to the bearing protection piece, and the bearing protection piece serves as a guide. The main shaft is inserted into the bearing slide piece so that no impact force is applied to the bearing slide piece.

[0010]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view orthogonal to the axial direction of the submersible bearing of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.
3 is a sectional view taken along the line BB of FIG. 1, and FIG. 4 is a view for explaining the action of the U groove formed in the cylindrical elastic body.

In the figure, the outer circumference of a cylindrical elastic body 10 made of synthetic rubber or the like is covered with a metal cylinder 12 and fixed by adhesion. Then, shallow U-shaped concave grooves 10a, 10a ... Are formed at regular intervals in the circumferential direction on the inner peripheral surface of the cylindrical elastic body 10 in the axial direction with a space therebetween, and between the concave grooves 10a, 10a. U-grooves 10b having a U-shaped cross section are formed in the axial direction. The bearing sliding pieces 14, 14 ... Are formed of a hard and wear-resistant ceramic such as silicon carbide or silicon nitride.
These bearing sliding pieces 14, 14 ... Are divided in the circumferential direction and have a width that allows them to fit into the recessed grooves 10a, 10a .. The concave arc-shaped surfaces 14a, 14a ... Are formed. The bearing sliding pieces 14, 14 ...
It is fixed to the cylindrical elastic body 10 by adhesive. In addition, at both ends of the bearing, the bearing sliding pieces 14, 1
4 is chamfered to facilitate the insertion of the main shaft 20.

In the underwater bearing having such a structure, as shown in FIG. 4, when a part of the bearing sliding piece 14 is strongly pressed by an eccentric load by the inserted main shaft 20, a part of the cylindrical elastic body 10 near the bearing sliding piece 14 is strongly pressed. Is strongly pressed and the U groove 10 near
The groove widths of b, 10b, ... Are narrowed and the shoulders thereof are raised to reduce the thickness of a part of the cylindrical elastic body 10 that is strongly pressed by the bearing sliding piece 14. At the same time, the load from the main shaft 20 is also applied to the bearing sliding pieces 14, 14 ... Provided next to the bearing sliding piece 14, and the posture thereof is appropriately changed. Thus, the cylindrical elastic body 10 is
The U-grooves 10b, 10b ... Can be easily elastically deformed by the increased area of the free surface, and the load of the main shaft 20 can be distributed by the plurality of bearing sliding pieces 14, 14 ... The position and attitude are changed.

Therefore, even if the main shaft 20 is subjected to an eccentric load, the bearing sliding pieces 14, 14 ...
4a ... Makes elastic contact with the main shaft 20, surface contact can be maintained, fluid lubrication is maintained in the lubrication state, the friction coefficient is small, and seizure etc. does not occur.

Moreover, the bearing sliding pieces 14, 14 ... Are integrated in the axial direction, and when the main shaft 20 is inserted, the main shaft 2 is inserted.
It suffices that careful work is performed when the end portion of 0 passes through the end surface of the bearing, which is the same as the conventional one using a cylindrical ceramic.

FIG. 5 is a sectional view taken along the axial plane of another embodiment of the submersible bearing of the present invention. The other embodiment shown in FIG. 5 differs from the embodiment shown in FIGS. 1 to 4 in the following points.

First, the bearing sliding pieces 24, 24 ... Are formed axially shorter than the cylindrical elastic body 10, and the recessed grooves 10a, 10a. Adhesively fixed. The bearing sliding pieces 24, 24 ... Having the same cross-sectional shape as the bearing sliding pieces 24, 24.
, And is bonded and fixed to the cylindrical elastic body 10 and the bearing sliding pieces 24, 24 ... This bearing protection piece 2
6, 26 ... Are formed of a resin having a higher elasticity than ceramics, such as polytetrafluoroethylene resin (PTFE) or carbon-containing phenol resin. And the bearing protection piece 2
6 and 26 are also provided with arcuate surfaces that are the same as the concave arcuate surfaces provided on the bearing sliding pieces 24.

In such a structure, when the main shaft 20 is inserted, an impact force from the main shaft 20 is applied to the bearing protection pieces 26, 26 ... Further, the bearing protection pieces 26, 26 ...
Acts as a guide to. Therefore, the bearing sliding pieces 24, 24
No impact force is applied to ..., There is no risk of destruction, and work is easy.

In another embodiment shown in FIG. 5,
The bearing protection pieces 26, 26, ... Are divided in the circumferential direction and arranged at intervals, but they may be cylindrical without division. The groove formed on the inner circumference of the cylindrical elastic body 10 is not limited to the U groove as in the embodiment, but may be a V groove, a U-shaped groove, a dovetail groove, or the like. Then, in another embodiment shown in FIG. 5, bearing protection pieces 26, 26 ...
However, the bearing protection pieces 26, 26 ... May be provided on at least one side into which the main shaft 20 is inserted.

[0019]

As described above, in the submersible bearing of the present invention, since the U-groove is provided on the inner periphery of the cylindrical elastic body, when a strong load is applied to the bearing sliding piece, that portion of the cylindrical elastic body is applied. Is easily elastically deformed, and the load is dispersed and carried by the plurality of bearing sliding pieces. Further, the bearing sliding piece can easily change its posture and come into surface contact with the main shaft by the easy elastic deformation of the cylindrical elastic body, and can always maintain the fluid lubrication action and have a small friction coefficient. Moreover, since the bearing sliding piece is integrated in the axial direction, the work for inserting the main shaft and the like is the same as the conventional work using the cylindrical bearing made of ceramic.

If the bearing protection piece is provided in close contact with the end surface of the bearing sliding piece, no impact force is applied to the bearing sliding piece when the main shaft is inserted, so that the insertion operation is facilitated.

[Brief description of drawings]

FIG. 1 is a sectional view of an underwater bearing of the present invention, which is orthogonal to the axial direction.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a view for explaining the action of a U groove formed in a cylindrical elastic body.

FIG. 5 is a cross-sectional view taken along a plane in the axial direction of another embodiment of the submersible bearing of the present invention.

[Explanation of symbols]

 10 Cylindrical Elastic Body 10b U-groove 12 Metal Cylindrical Body 14, 24 Bearing Sliding Piece 20 Spindle 26 Bearing Protecting Piece

Claims (2)

[Claims] 1. A plurality of bearing sliding pieces formed by coating a cylindrical elastic body with a metal tubular body and dividing it in a circumferential direction and integrally forming an axially hard and highly wear-resistant ceramic. The cylindrical elastic bodies are arranged at equal intervals in the circumferential direction at intervals inside the cylindrical elastic body, and axial grooves are formed in the inner periphery of the cylindrical elastic body where the bearing sliding pieces are spaced. A submersible bearing characterized by being installed. 2. The underwater bearing according to claim 1, wherein a bearing protection piece made of a resin richer in elasticity than the ceramic is provided on one side of the bearing sliding piece on at least one side of the axial direction where the main shaft is inserted. Placed in close contact with the end face,
An underwater bearing characterized in that an inner diameter formed by the bearing protection piece matches an inner diameter formed by the bearing sliding piece.