RU2453740C1 - Antifriction bearing - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: proposed bearing has outer and inner races, cage and solids of revolution. Note here that outer and inner diameters of cage, its length, weight, rpm, shear modulus of its material and number of solids of revolution are selected proceeding from:

where π=3.14. G is said shear modulus, d_o is cage OD, d_i - is cage ID, l is cage length, m is cage weight, ω_c is is cage rpm, and z is number of solids of revolution.

EFFECT: longer life.

Description

The invention relates to the field of mechanical engineering and can be used in aircraft, automobile and other types of engine building, in which high-speed and highly loaded rolling bearings are used.

Known ball and roller bearings, consisting of external and internal cages, a cage and rolling elements (Rolling bearings. A reference book edited by Spitsin N.A. and Strishevsky A.I. M .: Engineering, 1961).

It is known that in the loaded zone of the rolling bearing, the rolling body is unwound, and when entering the unloaded zone, the rotation of the rolling body slows down. When spinning, the rolling body hits the surface of the front baffle of the separator, trying to accelerate its rotation frequency, and when the rotation of the rolling body slows down, the rear surface of the baffle separator hits the rolling body, accelerating its movement. Thus, during the operation of the rolling bearing, there is an uneven (oscillatory) rotation of the cage around the bearing axis with an oscillation frequency equal to the product of the rotational speed by the number of rolling bodies.

An analytical study of the effect of the impact of rolling elements on the dynamics of the separator showed that with a harmonically changing disturbing force, an elastic separator, without taking into account the elasticity of other parts of the rolling bearing, will only work without resonance when the stiffness of the separator will satisfy the following inequality

where C _φ is the stiffness of the separator; J _c is the moment of inertia of the separator; ω is the circular frequency of the disturbing force, equal to the product of the separator rotation frequency by the number of rolling bodies.

Expressing C _φ through the flexibility of the separator, and J _c through its parameters (Handbook of the machine builder edited by Sorensen S.V. M .: Mashgiz, 1963), we obtain

where π = 3.14; G is the shear modulus of the separator material; d _{n is the} detecting diameter of the separator; d _n - the inner diameter of the separator; l is the length of the separator; m is the mass of the separator; ω _c is the speed of the separator; z is the number of rolling elements of bearings.

Engines of various types operate, as a rule, in a wide range of rotational speeds, at which the operation of the rolling bearing cage in the resonant mode is unacceptable. When the separator is operating in resonance mode, the operating conditions of all parts of the rolling bearing are significantly worsened, which significantly reduces their durability, and in some cases leads to fatigue damage of the separator and rolling elements, accompanied by severe consequences. The technical condition of the partitions of the seats of the roller bearings separators of aircraft engines that have been in operation confirms the operation of the separator in resonance mode.

A disadvantage of the known rolling bearing is the non-optimal choice of the outer and inner diameters of the separator, its mass, rotational speed, shear modulus of the material of which the separator is made, and the number of rolling elements, as a result of which its operation in resonant mode takes place at separate rotational frequencies of the separator.

The present invention is to increase the durability of the rolling bearing by eliminating the operation of the separator in resonance mode in the range of operating frequencies of rotation of the rolling bearing.

The task is achieved in that the outer and inner diameters of the separator, its length, mass, speed, shear modulus of the material of which the separator is made, and the number of rolling elements are selected in accordance with the ratio

,

,

where π = 3.14; G is the shear modulus of the separator material; d _n - the outer diameter of the separator; d _in - the inner diameter of the separator; l is the length of the separator; m is the mass of the separator; ω _c is the speed of the separator; z is the number of rolling elements of bearings.

If the separator parameters are not complied with the proposed ratio, the separator can operate in resonance mode in certain modes, under which the working conditions of the rolling bearing parts are significantly worsened, which reduces its durability, and in some cases leads to fatigue damage of the separator and rolling elements, accompanied by severe consequences.

Thus, the manufacture of a rolling bearing in accordance with the proposed ratio will exclude the operation of the separator in resonance mode over the entire range of operation of the rolling bearing, which will increase its durability.

Using the proposed technical solution will significantly increase the resource and reliability of high-speed and high-loaded rolling bearings, reduce the premature removal from operation and unscheduled overhaul of expensive aircraft and automobile engines on which rolling bearings are installed, which will save financial and material resources.

Claims (1)

A rolling bearing containing outer and inner bearings, a cage and rolling elements, characterized in that the outer and inner diameters of the cage, its length, mass, speed, shear modulus of the material of the cage, and the number of rolling elements are selected in accordance with the ratio :

,
where π = 3.14; G is the shear modulus of the separator material; d _n - the outer diameter of the separator; d _in - the inner diameter of the separator; l is the length of the separator; m is the mass of the separator; ω _with - the speed of the separator; z is the number of rolling elements in the bearing.