RU2391579C1 - Friction facing - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: length of facing arc along internal surface and difference of thickness of facing on ends corresponds to ratio:

where H₂ is thickness of thick end of facing, H₁ is thickness of thin end of facing, and L is length of facing arc along internal surface.

EFFECT: improved frictional characteristics of friction pair due to optimal correspondence of facing geometry to distribution of forces and pressure in drum brake.

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Description

The invention relates to friction linings, and in particular to the linings of the drum brakes of vehicles, in particular trucks.

An analogue of the claimed invention is a friction lining, in which the ratio between the length of the arc of the lining on the inner surface and the difference in thickness of the lining on the edges is 62 ÷ 67 (see Friction and sealing products and materials. Directory-catalog. M .: TSNIITENeftekhim, 1990, p. 69). The essential features of the analogue "friction lining" coincide with the essential features of the claimed invention.

The disadvantage of the analogue is the lack of full correspondence of the lining geometry to the distribution of forces and pressures in the drum brake, which impairs the tribological characteristics of the brake friction pair.

The prototype of the claimed invention is a friction lining, in which the ratio between the length of the arc of the lining on the inner surface and the difference in thickness of the lining on the edges is 37 ÷ 41 (see Asbestos technical products. Directory-directory. M .: TSNIITENeftekhim, 1984, p. 64 -68). The essential features of the prototype "friction lining" coincide with the essential features of the claimed invention.

The disadvantage of the prototype is also the lack of full compliance with the geometry of the lining distribution of forces and pressures in the drum brake, which affects the tribological characteristics of the friction pair.

The task to which the invention is directed is to improve the tribological characteristics of the friction pair by ensuring optimal matching of the lining geometry to the distribution of forces and pressures in the drum brake.

, где H₂ - толщина толстого края накладки; H₁ - толщина тонкого края накладки; L - длина дуги накладки по внутренней поверхности.To achieve the technical result in the friction lining, the length of the lining arc along the inner surface and the difference in thickness of the lining along the edges corresponds to the ratio:

where H ₂ is the thickness of the thick edge of the lining; H ₁ is the thickness of the thin edge of the lining; L is the length of the lining arc along the inner surface.

, где H₂ - толщина толстого края накладки; H₁ - толщина тонкого края накладки; L - длина дуги накладки по внутренней поверхности» являются отличительными от признаков прототипа.The essential features of the claimed invention “the length of the lining arc on the inner surface and the difference in thickness of the lining at the edges corresponds to the ratio:

where H ₂ is the thickness of the thick edge of the lining; H ₁ is the thickness of the thin edge of the lining; L - the length of the arc lining on the inner surface ”are distinctive from the features of the prototype.

The drawing shows the claimed overlay, side view.

, где Н₂ - толщина толстого края накладки; H₁ - толщина тонкого края накладки; L - длина дуги накладки по внутренней поверхности.The friction pad is made of a polymer friction composite and is part of a cylindrical shell of variable thickness, equipped with two or three rows of rivet holes. The pad has a variable thickness H in the working area (the area corresponding to the friction contact surface during operation). For pads having side bevels 1 (shown in the drawing), the thickness H is determined with respect to the working surface 2 of the pads as the minimum H ₁ and maximum H ₂ . If the plate does not have side bevels (not shown in the drawing), then H ₁ and H _{2 are} determined for the edges of the plate. The difference between H ₂ and H ₁ determines the gradient of the thickness of the lining in the area of the working surface. The length L of the lining along the arc of the inner (non-working) surface 3 corresponds to the gradient of the thickness of the lining as 35 ÷ 36, i.e.

where H ₂ is the thickness of the thick edge of the lining; H ₁ is the thickness of the thin edge of the lining; L is the length of the lining arc along the inner surface.

.A specific example of the claimed lining is a drum brake lining of a truck having bevels, in which L≈154 mm, H ₁ ≈14.4 mm, H ₂ ≈18.7 mm.

.

The overlay can be made by known methods, for example, molding with subsequent mechanical processing.

Performing the lining with the specified coordinate characteristics when using the lining in the drum drum brake allows you to create a pressure difference (thanks to the expanding device), ensuring uniform friction and wear of the lining, the same braking torque in both directions of rotation, as well as the effect of self-reinforcement, that is, an increase in the braking effect by forces friction. As a result, tribological characteristics of the brake are improved.

Claims (1)

Friction lining, characterized in that the length of the lining arc on the inner surface and the difference in thickness of the lining on the edges corresponds to the ratio

where H ₂ is the thickness of the thick edge of the lining; H ₁ is the thickness of the thin edge of the lining; L is the length of the lining arc along the inner surface.