JP2004347133A - Slide bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slide bearing composed of a resin material, having the high cooling effect by a superior heat transfer characteristic, and having high allowable sliding speed and allowable bearing pressure. <P>SOLUTION: This slide bearing 1 is used for a rotary machine, and a bearing part is composed of a carbon fiber reinforced resin material molded by heating pressurizing work, by winding carbon fiber 2 coated with a thermoplastic resin in a coil shape to the axis. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sliding bearing device using a resin material, and more particularly to a sliding bearing device having a high allowable sliding speed and a high allowable surface pressure, which has good heat transfer characteristics and can remove sliding heat satisfactorily.

  Bearings made of resin or fiber reinforced resin filled with relatively short carbon fiber or glass fiber, etc., can slide dry on office machines, turbo pumps and other rotating machines due to their good lubrication performance. Widely used as bearings. These resin or fiber reinforced resin plain bearings are formed by using a resin as a base of fluorine, polyimide, polyamide, polyethylene or the like and adding a special filler thereto. These bearings are characterized by the resin material used as the base.For example, bearings using fluororesin are extremely excellent in low friction and wear resistance, non-adhesion, heat resistance, chemical resistance, and weather resistance. There is a feature. In addition, polyimide-based resin bearings are characterized by having excellent heat resistance and strength characteristics.

  As a resin bearing oriented to a high allowable sliding speed and a high allowable surface pressure, a fiber reinforced resin material formed by mixing a resin with carbon fiber, glass fiber, a solid lubricant or the like is used. It has been reported that the use limits of these bearings are 3.3 m / sec, the allowable slip speed, and 3.3 MPa / sec, the limit pv value (the product of the allowable slip speed and the allowable surface pressure), even for a bearing material based on polyimide.

  However, the resin constituting the above-mentioned bearing is a lubricant and also functions as a heat insulator. Therefore, the sliding heat with the shaft sleeve (the mating material) with which the bearing contacts does not transfer, and the resin temperature rises. If the heat resistance of the resin is not good, the resin is dissolved or thermally degraded, resulting in a low limit pv value. In addition, since the outer periphery of the cylindrical bearing is generally constrained by the metal shell, there is a problem that the heat generated by sliding with the shaft sleeve (the mating material) reduces the inner diameter of the bearing and causes sticking.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a sliding bearing made of a resin material having a high cooling effect due to good heat transfer characteristics, a high allowable sliding speed, and a high allowable surface pressure.

The sliding bearing device of the present invention is a sliding bearing used for a rotary machine, and the bearing portion is formed by winding carbon fiber coated with a thermoplastic resin in a coil shape around an axis, and performing heating and press working. It is characterized by being made of a carbon fiber reinforced resin material molded by the method described above.
Further, the allowable sliding speed of the bearing portion is more than 3.9 m / s.
A rotating machine according to the present invention is characterized by using the above-mentioned plain bearing device.

  Since the long carbon fiber having a high thermal conductivity is wound in a coil shape, sliding heat with the shaft sleeve (counterpart material) can be quickly removed. Further, the carbon fiber has an extremely low linear expansion coefficient as compared with a resin material. For this reason, even if the outer periphery of the cylindrical bearing is constrained by the metal cells, the problem that the inner diameter is reduced due to heat generated by sliding and stick is prevented is prevented, and the high allowable sliding speed and high allowable surface pressure of the bearing are reduced. Achieved.

  The sliding bearing of the present invention is obtained by winding continuous carbon fibers into a coil shape and filling the gap with a thermoplastic resin, so that high heat conductivity is obtained and a high cooling effect is obtained. At the same time, excellent characteristics such as low friction and abrasion resistance, non-adhesion, heat resistance, and chemical resistance of a resin such as PEEK or PI can be exhibited as they are. As a result, problems such as a decrease in the inner diameter due to frictional heat with the shaft sleeve, which is observed in conventional resin bearings or fiber-reinforced resin bearings, and the occurrence of sticks, are solved, and a high allowable sliding speed and allowable surface pressure are obtained.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1A shows a slide bearing device according to one embodiment of the present invention. The outer shape of the bearing of this embodiment is the same as that of a normal resin bearing. In the case of this embodiment, the inner diameter is about 75 mm, the outer diameter is about 90 mm, and the length is about 32 mm. The bearing 1 is formed by winding a resin-coated carbon fiber in a coil shape around a shaft core, and is a kind of carbon fiber reinforced resin material.

  FIG. 1B is a partially enlarged sectional view of the inside of the bearing in a section parallel to the axis. As shown in FIG. 1B, a strand-like carbon fiber 2 obtained by twisting ultra-fine carbon fibers having a thickness of about several μm is formed by being embedded in a resin 3. The resin 3 is formed by a thermoplastic resin coated around a carbon fiber, for example, PEEK (poly ether ether tetone) or PI (polyimide), which is plastically deformed and fused by heating and pressing. It is formed by solidification. That is, a long carbon fiber having a large thermal conductivity and a small coefficient of linear expansion is embedded in a thermoplastic resin having high heat resistance and high lubricity.

  Since the carbon fiber reinforced resin of the present invention is a long continuous fiber, when sliding heat is generated due to friction with the shaft sleeve of the bearing, rapid heat conduction occurs and heat is quickly released. be able to. This is different from the case where the relatively short carbon fiber or glass fiber of the prior art is mixed into the thermoplastic resin, without causing a decrease in the heat transfer coefficient due to heat transfer between different materials due to the dispersion of the reinforcing fibers. The bearing can be cooled quickly. In addition, since the linear expansion coefficient of carbon fiber is small, circumferential elongation at the time of heat generation can be suppressed. Even if the outside of the bearing is constrained by the metal shell, the inner diameter is generated by the heat generated by sliding with the shaft sleeve. And the problem of sticking is prevented.

  FIG. 2 is a diagram illustrating a use state of the plain bearing according to one embodiment of the present invention. A metal sleeve 11 such as stainless steel, which is a mating material of a bearing, is fitted around the outer periphery of the rotating shaft 10. The outer peripheral surface of the sleeve 11 slides on the inner peripheral surface of the slide bearing 1 described above. The outer periphery of the slide bearing 1 is fixed to a casing of a rotating machine via a flange portion 13 by a metal bearing case 12.

  According to the results of the dry sliding test, the sliding bearing (type D) of the above-described embodiment has obtained the following good sliding characteristics using austenitic stainless steel as a sliding partner material.

  That is, the bearing type A is a bearing made of PI (polyimide resin), and stops at a relatively low bearing sliding speed (3.9 m / s) with a large torque after 120 seconds. The bearing type B is a bearing made of PEEK (poly ether ether tetone), and stops at a relatively low bearing slip speed (3.9 m / s) immediately after starting due to a large torque. The bearing type C is a fiber reinforced resin bearing mixed with a relatively short glass fiber, and the sliding surface is melted at a relatively low bearing slip speed (3.9 m / s).

  The bearing type D is the bearing of the above embodiment, and has good characteristics exceeding the conventional usage limit, a slip speed of 13 m / sec or more, a bearing surface pressure of 0.30 MPa, and a limit PV value of 3.9 MPa / s. Have been obtained.

  FIG. 3 is a diagram showing a manufacturing process of the above-described plain bearing. A strand-shaped fine wire 2 in which long carbon fibers are coated with a PEEK-coated ultra-fine wire is wound around a bobbin 20 while applying a temperature and a pressure with a roller 21. When the roller 21 is heated and pressurized, the resin (PEEK) coating the carbon fiber has thermoplasticity, so that the resin is softened and becomes compatible with the resin of the adjacent fine wire 2. Then, after passing through the heating and pressurizing portion by the roller 21, the resin is cooled, so that the resin is solidified. Then, as shown in the enlarged cross-sectional view of FIG. 1B, a fiber-reinforced resin in which continuous long carbon fibers 1 are wrapped with a resin 2 is formed. Then, the bobbin 20 is pulled out and cut to a required size, whereby the bearing 1 is manufactured.

1A is a perspective view of a sliding bearing device according to an embodiment of the present invention, and FIG. FIG. 2 is an explanatory view of a use state of the slide bearing of FIG. 1. FIG. 2 is an explanatory view showing a manufacturing process of the plain bearing of FIG. 1.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Slide bearing 2 Carbon fiber 3 Thermoplastic resin 10 Rotating shaft 11 Sleeve 12 Bearing case 20 Bobbin 21 Roller

Claims (3)

  A sliding bearing used for a rotary machine, wherein the bearing portion is a carbon fiber reinforced resin material formed by winding carbon fiber coated with a thermoplastic resin in a coil shape around a shaft core, and molding by heating and pressing. A plain bearing device characterized by comprising:   The sliding bearing device according to claim 1, wherein an allowable sliding speed of the bearing portion exceeds 3.9m / s. A rotary machine using the slide bearing device according to claim 1.

Images