RU2377449C2 - Friction bearing - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine building, particularly to friction bearing, manufactured from non-metallic composite materials and can be used in friction couples, provided for operation as in normal conditions as in corrosive working mediums at specific pressure up to 250 MPa, sliding velocity up to 5 m/s. Friction bearing of cylindrical shape contains pressure vessel implemented for instance from glass-fibre plastic, antifrictional layer and thrust collar. Thrust collar is glued to pressure vessel and is implemented perpendicularly to longitudinal axis of bearing axis. Antifrictional layer is connected to pressure vessel through damping layer, implemented, for instance from glue film VK-3. Thrust collar is implemented from both sides by butts of pressure vessel. Thrust collar is implemented from flat plate, manufactured from coal plastic or coal glass-fibre plastic.

EFFECT: increasing of axial durability of bearing, excluding of exfoliation between antifriction and pressure layers, that increases life time and increases reliability of products operation.

4 cl, 1 dwg

Description

The invention relates to mechanical engineering, namely to sliding bearings made of non-metallic composite materials, and can be used in friction pairs designed to work both under normal conditions and in aggressive working environments with a specific pressure of up to 250 MPa, sliding speed of up to 5 m / s

A sliding bearing is known, consisting of sliding elements in the form of concave strip-like bearing shells made of polymer carbon-containing materials and a housing in the form of a bearing strip with locking edges covering the bearing shells (see Utility Model Certificate No. 25058 with priority dated January 24, 2002).

The disadvantages of this technical solution are: the ability to perceive only radial loads, the high complexity of manufacturing strip-like bearing shells, galvanic couple formed by a metal carrier strip and carbon-containing material of the liners.

A known bearing with a working surface of glued self-lubricating material containing a substrate of fiberglass material on a profiled metal surface on which a self-lubricating fibrous material is impregnated, impregnated with a reinforcing liquid polymer, pressed over the fibers under tension to adhere to the substrate. After the polymer has cured, part of the compressed fibers are removed until the self-lubricating layer is exposed (see US Patent No. 5431500, published August 26, 1992).

The disadvantages of this bearing are: its perception of only radial loads, during heating, the appearance of delamination at the interface between the metal profiled surface and the substrate of fiberglass material due to the difference in the coefficients of thermal expansion.

A sliding bearing is known, which has a cylindrical surface and consists of a power fiberglass housing and an antifriction layer made of carbon fibers impregnated with a binder (see utility model certificate No. 16615 with priority dated July 19, 2000)

The specified technical solution as the closest analogue can be taken as a prototype.

The disadvantages of the prototype are:

- the perception of only radial mechanical loads;

- the contact zone between the power housing and the antifriction layer is subjected to increased loads both from mechanical stresses on the bearing and from thermal loads (heating - cooling) due to different coefficients of thermal expansion of the materials of the housing and the antifriction layer.

The tasks to which the present invention is directed are:

- increase in axial strength of the bearing;

- the exclusion of delamination between the antifriction and power layers.

The essence of the invention is illustrated in the drawing, which shows one of the embodiments of a sliding bearing.

The sliding bearing comprises a power housing 1, which is provided at one end with a thrust shoulder 2 glued to the housing 1 perpendicular to the longitudinal axis of the bearing. On the inner side of the housing 1 is an anti-friction layer 3, connected to the housing 1 through a damping layer 4, for example, from an adhesive film VK-3.

The antifriction layer 3 is made of carbon fiber containing a carbon tape LU-P 0.2, impregnated with phenol-formaldehyde binder FFE-70.

The thrust collar 2 can be installed on both sides at the ends of the power housing, while the collar, for example, is made in the form of a ring glued to the power housing 1.

The thrust collar 2 may be in the form of a ring made of a flat carbon fiber plate or a combined material, for example carbon fiber.

A special set of accessories for machining allows the manufacture of bearings with high accuracy.

To fulfill the conditions of self-lubrication of the antifriction layer 3 and reduce the friction coefficient along the counterbody, vacuum impregnation of the sliding bearing with industrial oil can be applied.

The bearing is worn with an inner diameter on a rotating axis (not shown) with a minimum clearance, and the bearing housing 1 with a glued flange is installed in the power housing of the mechanism in which the bearing is mounted (not shown conditionally).

When the axis rotates, its cylindrical surface interacts with the inner surface of the antifriction layer 3, on the carbon fibers of which an “crushed” carbon layer forms under the axis pressure, which ensures the minimum coefficient of friction of the axis in the bearing. This is facilitated by the preliminary impregnation of the bearing with industrial oil, which, emerging from micropores, contributes to an additional decrease in the coefficient of friction.

When axial loads occur on the bearing, they act on the shoulder 2, which is fixed in the power case of the mechanism.

During the operation of the bearing heat is generated, which heats the antifriction layer 3, and then the power housing 1. Due to the difference in the coefficient of thermal expansion (KTR) of the materials of the antifriction layer 3 (KTR of unidirectional carbon fiber-based LU-P 0.2 tape along the fibers is ~ 2.5 × 10 ^-6 1 / С °) and of the power casing 1 (KTR fiberglass based on T-10 fiberglass along the warp fibers is ~ 9 × 10 ^-6 1 / С °) stresses can arise at their boundary that can "Stratify" the bearing. To eliminate stresses, a damping layer 4 is installed at the boundary of these layers, which, due to its elasticity, compensates for the deformation of adjacent layers of the bearing.

Thus, the proposed sliding bearing during operation as part of the mechanism provides:

- increase in axial strength;

- the exception of delamination between the antifriction layer 3 and the power housing 1.

In accordance with the proposed design of the plain bearing, prototypes with an inner diameter of 10 mm were manufactured.

The tests were held at the Taganrog Aviation Scientific and Technical Complex. G.M.Berieva (Taganrog). The results of the tests fully satisfy the technical requirements and confirm the functionality and reliability of the sliding bearing.

Claims (4)

1. A cylindrical plain bearing comprising a power housing made of fiberglass and an antifriction layer, characterized in that a thrust shoulder is glued to the power housing, and the thrust shoulder is perpendicular to the longitudinal axis of the bearing. 2. The sliding bearing according to claim 1, characterized in that the antifriction layer is connected to the power housing through a damping layer made, for example, of VK-3 adhesive film. 3. The sliding bearing according to claim 1, characterized in that the thrust shoulder is made on both sides at the ends of the power housing. 4. The sliding bearing according to claim 1, characterized in that the thrust shoulder is made of a flat plate made of carbon fiber or carbon fiber.

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