JPH0276927A - Ceramic bearing - Google Patents

Abstract

PURPOSE:To give wear resistance to a ceramic bearing, thereby removing the restriction on the bearing force, and to give shock resistance to the bearing by fitting a hub-ring-body to the outside of a ceramic bearing body that supports a revolving shaft and installing the outside of this hub-ring-body to a fixed body via an elastic, intermediate supporting member. CONSTITUTION:A revolving shaft 1 is inserted into a cylindrical and ceramic bearing body 2 that supports the shaft 1, and a plurality of lubricating grooves 2a are formed at the inner surface of this ceramic bearing body 2. In addition, a hub-ring-body 3 made of metal is firmly attached to the other surface of this ceramic bearing body 2 by means of silver-alloy brazing, while the outside of this hub-ring-body 3 is fixed to a fixed body 5 like a casing via elastic, intermediate supporting members 4, which are in the shape of radial spokes 4. The elastic, intermediate supporting members 4, which are in the shape of radial spokes, can absorb impulsive force, because when the intermediate, supporting members (4) are subjected to vertical and impulsive stresses, they can slightly deform themselves, maintaining a certain degree of strength.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a ceramic bearing used, for example, as a water-lubricated bearing of a hydraulic machine used underwater.

(Prior art) Ceramic bearings used in this type of water-lubricated bearings, which have already been proposed, are bearings that support rotating shafts using water or seawater as a lubricant. has low viscosity.

That is, for example, the viscosity coefficient of water at 40°C is 0.6
5X10-3NS/go, oil is 5X10-3NS
/ It's about 100%.

Therefore, the load capacity (the weight of the rotating shaft that can be supported by the pressure of the lubricating fluid in the bearing) is small, and during transient periods (such as when starting or stopping the rotating shaft, or when a sudden external force is applied to the rotating shaft)
In this case, the lubricating film is easily damaged, and for this reason, the above-mentioned water-lubricated bearings are made of materials that do not cause abnormalities immediately even if the bearing and the rotating shaft come into contact. .

In other words, the above-mentioned water-lubricated bearings usually include resin bearings and carbon bearings. Bearings made of resin are strong against impact, and because they contain water, even if they generate heat due to local contact, It can withstand enough.

On the other hand, bearings made of carbon material have characteristics such as being highly self-lubricating (carbon powder acts as a lubricant) and not causing dimensional errors unlike bearings made of resin material.

(Problem to be solved by the invention) However, both the above-mentioned resin material bearings and carbon bearings have low wear resistance (particularly when water mixed with slurry etc. is used as a lubricant). has long-term reliability and safety problems as a bearing material.

On the other hand, hard rubber bearings developed as bearings for ships can respond to foreign objects by deforming the rubber;
This is limited to cases where water as a lubricant is constantly replenished; if water supply is insufficient for some reason, not only is there a risk of immediate seizure and burnout, but also blood pressure (load per unit area) It is difficult to support a rotating shaft with a high load due to the inability to obtain a large There are also restrictions, making it difficult to design with a high degree of freedom.

The present invention has been made in view of the above-mentioned circumstances, and aims to use a T1 ceramic material that is wear-resistant and not restricted by blood pressure, and to provide a ceramic bearing that is impact-resistant. do.

[Structure of the invention]

(Means for Solving the Problems and Their Effects) The present invention includes a base metal ring inserted on the outside of a ceramic bearing body that supports a rotating shaft, and an elastic intermediate support member connected to the outside of the base metal ring. It is designed so that it can be attached to a fixed body, has wear resistance, eliminates restrictions due to surface pressure, and is impact resistant.

(Embodiment) Hereinafter, an illustrated embodiment in which the present invention is applied to an underwater bearing will be described.

1 and 2, reference numeral 1 denotes a rotating shaft held horizontally, and this rotating shaft 1 is fitted into a cylindrical ceramic bearing body 2 that supports the rotating shaft 1. A plurality of lubricating grooves 2 a are formed on the inner circumference of the bearing body 2 . Moreover, on the outside of the ceramic bearing body 2,
A metal base ring body 3 is firmly attached by silver brazing, and an elastic intermediate support member 4, such as a radial spoke, is provided on the outside of the base metal ring body 3.
For example, it is attached to a fixed body 5 such as a casing.

Therefore, although the intermediate support member 4 having elasticity like the radial spokes maintains a certain degree of strength against impact stress in the vertical direction, it can withstand the impact due to slight deformation of the intermediate support member 4 itself. Since the force can be absorbed, no impact force is applied to the ceramic bearing body 2 itself, and since the ceramic bearing body 26 has mechanical strength, the load on the rotating shaft 1 is reduced. can be fully supported. Furthermore, since the intermediate support member 4 itself maintains slight deformation even when the rotating shaft 1 bends, it also has flexibility.

On the other hand, by attaching a viscoelastic material such as lead to all or part of the intermediate support member 4, it is possible to add a large damping effect to vibrations and impact forces from the rotating shaft 1. .

In this way, the present invention makes it possible to effectively exhibit the wear resistance of the ceramic bearing body 2 itself while compensating for the low impact resistance of the ceramic bearing body 2 itself with the elastic intermediate support member 4. It has become.

Note that if the sliding portion of the rotating shaft 5 is overlaid with a superhard material such as tungsten carbide, a bearing device with mutually high wear resistance can be obtained.

Next, another embodiment of the present invention shown in FIGS. 3 and 4 has a plurality of windows 4a in the cylindrical body portion of the cylindrical intermediate member 4.
The intermediate member 4 itself is provided with elasticity to increase its impact resistance. Further, this cylindrical intermediate member 4 is made small to facilitate centering work during assembly.

On the other hand, in another embodiment of the present invention shown in FIGS. 5 and 6 (A) and (B), a plurality of outer circumferential grooves 3a are formed on the outer circumference of the base ring body 3, and each outer circumferential groove 3a Inner circumferential grooves 5a are formed in the fixed body 5 facing the fixed body 5, and intermediate members 6 are formed between the outer circumferential grooves 3a and the inner circumferential grooves 58, and are made of an elastic vibrator-like ring or an O-ring made of a metal material. The intermediate member 6 is inserted in such a way that it does not shift, thereby adding elasticity to the intermediate member 6 itself and increasing its impact resistance.
As shown in Figure (B), it is designed to have a damping effect as well as deformation due to external force.

〔Effect of the invention〕

As described above, according to the present invention, the base ring body 3 is inserted on the outside of the ceramic bearing body 2 that supports the rotating shaft 1, and the outside of the base metal ring body 3 is connected to the outside of the base metal ring body 3 via the elastic intermediate support member 4. Since it is attached to the fixed body 5 by the ceramic bearing body 2, it is not only possible to effectively exert the wear-resistant function of the ceramic bearing body 2, but also eliminate the restriction due to surface pressure, and furthermore, the function of the intermediate support member 4 having elasticity can be achieved. It also has excellent effects such as being able to effectively utilize it to improve impact resistance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the ceramic bearing of the present invention, FIG. 2 is a top side view of the same, and FIGS. 3 to 6 (A). (B) is each figure which shows the other Example of this invention. 1...Rotating shaft, 2...Ceramic bearing body, 3...
Base ring body, 4... intermediate support member, 5... fixed body. Applicant's agent Mr. Sato

Claims (1)

[Claims] A ceramic bearing characterized in that a base ring body is inserted on the outside of a ceramic bearing body that supports a rotating shaft, and the outside of the base metal ring body is attached to a fixed body via an elastic intermediate support member.