Composite brake shoe for a railway vehicle

Abstract

This utility model relates to brake shoes for railway vehicles operating in triboconjugation with the wheel tread. The brake shoe for a railway vehicle comprises a metal frame and a heat-conducting composite friction element with a polymer matrix of rubber vulcanizate containing dispersed fillers. To nucleate the liquid products of thermal decomposition of the polymer matrix during operation, a mixture of magnesium hydrosilicate particles in fine-fiber and lamellar forms is additionally placed into the composite polymer matrix.

Description

[0001] The utility model relates to brake shoes of railway vehicles, for example, brake shoes of passenger and freight cars, electric trains, locomotives and other rail transport, operating in tribocoupling with the rolling surface of the wheel.

[0002] An analogue of the claimed utility model is a composite brake shoe for a railway vehicle, comprising a metal frame and a heat-conducting composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed, including particles of cryptocrystalline and crystalline graphite (see B.A. Shiryaev. Production of brake shoes from composite materials for railway cars. Moscow, "Chemistry", 1982. p. 16). The essential features of the analogue "metal frame, composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed" coincide with the essential features of the claimed utility model.

[0003] The disadvantage of the analogue is the deterioration of the performance characteristics of the pad due to the increased possibility of the formation of liquid decomposition products of the polymer matrix of the composite (in the case of significant operational heating of the pad), which significantly worsen the main friction characteristics (coefficient of friction, spreadability on the counterbody) of the brake pad.

[0004] Another analogue of the claimed utility model is a composite brake shoe for a railway vehicle, including a metal frame and a composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed (see B.A. Shiryaev. Production of brake shoes from composite materials for railway cars. M., "Chemistry", 1982. p. 15). The essential features of the analogue "metal frame, composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed" coincide with the essential features of the claimed utility model.

[0005] The disadvantage of the analogue is also a decrease in the performance characteristics of the pad due to the formation of liquid products of thermal decomposition of the polymer matrix of the composite during significant operational heating.

[0006] The prototype of the claimed utility model is a railway vehicle shoe, comprising a metal frame and a composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers and free sulfur particles are placed (see patent RU 227660, IPC B61N 1 / 00, 2024). The essential features of the prototype "metal frame, composite friction element, polymer matrix of rubber vulcanizate, dispersed fillers" coincide with the essential features of the claimed utility model.

[0007] A disadvantage of the prototype is also the possibility of the formation of liquid products of the polymer matrix of the composite during significant operational heating of the pad, which worsens its performance characteristics.

[0008] The task that the claimed utility model is aimed at solving is to improve the performance characteristics of the pad.

[0009] The technical result, which the claimed utility model is aimed at obtaining, is the nucleation of liquid polymer products of thermal decomposition of the polymer matrix during the operation of the shoe.

[0010] To achieve the specified technical result in a composite brake shoe of a railway vehicle, including a metal frame and a composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed, a mixture of magnesium hydrosilicate particles in fine-fiber form with magnesium hydrosilicate particles in lamellar (layered) form is additionally placed in the polymer matrix.

[0011] The essential features of the claimed utility model “a mixture of magnesium hydrosilicate particles in fine-fiber and plate-like forms” are distinctive from the features of the prototype.

[0012] A composite brake shoe for a railway vehicle comprises a metal frame, such as a steel mesh-wire or stamped frame, and a polymer composite friction element made of a macroheterophase material (composite). The polymer composite matrix is ​​made of rubber vulcanizate, such as SKD. The matrix contains dispersed components, including a pre-fabricated mixture of fine-fiber magnesium silicate hydrous particles and lamellar magnesium silicate hydrous particles.

[0013] The claimed block can be manufactured using known methods.

[0014] A specific example of the claimed invention is a composite brake shoe for a railway vehicle, made from a polymer composite comprising a polymer matrix of SKD rubber vulcanizate. The matrix contains particles of barite concentrate, particles of technical carbon, and a pre-prepared mixture of asbestos and talc particles. The amount of talc particles in the mixture ranges from 10% to 15%.

[0015] Since fine-fiber magnesium hydrosilicate has high sorption properties, lamellar magnesium hydrosilicate promotes the crystallization of liquid polymers (nucleation), and their mutual mixture promotes contact of sorbed liquid degradation products with the nucleating agent. This prevents the release of liquid degradation products of the polymer matrix onto the friction surface, which improves the performance characteristics of the brake pad. The ratio between the forms of magnesium hydrosilicate, when the content of the fine-fiber form in the particle mixture is from 85% to 90%, is optimal. If the content of the fine-fiber form exceeds 90%, the nucleation effect is insufficient, and if it is less than 85%, an insufficient amount of liquid wear products is sorbed.

Claims

A shoe for a railway vehicle, comprising a metal frame and a heat-conducting composite friction element with a polymer matrix of rubber vulcanizate, in which dispersed fillers are placed, characterized in that a mixture of magnesium hydrosilicate particles in fine-fiber form with magnesium hydrosilicate particles in lamellar form is additionally placed in the polymer matrix.