Ball bearing

Abstract

FIELD: mechanical engineering.SUBSTANCE: invention relates to the production of bearings in power engineering and engine building. A ball bearing is proposed, consisting of outer and inner rings, a separator and balls, wherein the ball has a gradient internal structure with a radially variable distribution of material density, a central cavity filled with gas, an outer annular channel located at the surface of the ball and filled with a viscous liquid, an inner annular channel located between the central cavity and the outer channel, filled with a heavy liquid, cavities with viscous liquid are installed on the separator between the balls and are rigidly connected to it.EFFECT: reliability and durability of the bearing is increased by improving the design.1 cl, 4 dwg

Description

[0001] The invention relates to the field of mechanical engineering, in particular, to the production of bearings in power engineering and engine building.

[0002] A radial ball bearing is known, comprising an inner ring, an outer ring, balls of two different diameters, alternately located in annular grooves. At the end of the fixed ring of the ball bearing, the direction of the radial load on the ball bearing is fixed. In this direction, it is necessary to increase the service life of the ball bearing in the product. This service life is increased by reducing the rigidity of the fixed ring when contacting the ball in this direction by a maximum of cosB times, where B is the central angle between the balls of the larger diameter, and by increasing the contact area of ​​the ball with the fixed ring of the ball bearing in this direction (RU Patent 2519105 C2, 2012). However, this device has limited efficiency and a low service life at high speeds.

[0003] The closest technical solution is a ball bearing consisting of outer and inner rings and hollow balls. Half of the complete set of balls is assembled with the rings with an interference fit, while the other half is assembled with a clearance. The balls assembled with an interference fit and with a clearance alternate (RU Patent 252814937, 2024). However, this device has limited efficiency at high speeds and is highly complex.

[0004] Technical result - increased reliability and durability of the bearing due to improved design.

[0005] It is achieved by the fact that in a device consisting of outer and inner rings, a separator and balls, wherein the ball has a gradient internal structure with a radially variable distribution of the material density, a central cavity filled with gas, an outer annular channel located at the surface of the ball and filled with a viscous liquid, an inner annular channel located between the central cavity and the outer channel, filled with a heavy liquid, on the separator between the balls, cavities with a viscous liquid are installed and rigidly connected to it.

[0006] The use of a gradient ball bearing structure helps dampen inertial disturbances during high-speed operation and when resonance occurs. For example, at a rotation speed of 10,000 rpm and a bore diameter of 0.5 mm, the compensating effect is determined by the formulas:

[0007]

[0008] where M тр- moment of friction force when liquid lags under high inertial loads, I ж - moment of inertia of the liquid inside the ball, m 1, m2 - masses of liquids, r1, r2 - reduced diameter of cavities with liquid, t 10 - vibration damping time by 10 times at resonance, s, Δω - change in the angular velocity of rotation of the ball over time Δt, ζ - relative damping coefficient, ω - angular velocity.

[0009] The installation of cavities on the separator provides additional operational reliability when exposed to vibration loads and torsional oscillations of variable modes. The damping effect of the cavities was determined using the following formulas:

[0010]

[0011] where ω0 is the natural frequency of torsional vibrations, k θ - torsional stiffness of the system, I сеп - moment of inertia of the separator, s кр - critical damping coefficient, ζ θ - relative damping coefficient, s θ- the actual torsional damping coefficient created by the viscous liquid in the separator cavity.

[0012] The drawing schematically shows the proposed device (Fig. 1 - sectional view of a ball bearing, Fig. 2 - sectional view of a cavity with liquid on a separator, Fig. 3 - sectional view of a rolling element, Fig. 4 - sectional view of a rolling element).

[0013] The device comprises an outer 1 and inner 2 rings, balls 3 and a separator 4 mounted on the balls 3, between the rings 1 and 2, wherein the ball has a gradient structure consisting of a central cavity 5, an outer annular channel 6 located near the surface of the ball and filled with a viscous liquid, an inner annular channel 7 located between the central cavity and the outer channel, filled with a heavy liquid, on the separator 4 between the balls 3 cavities with liquid 8 are installed and rigidly connected to it. The device operates as follows:

[0014] The central cavity of the ball, constantly filled with nitrogen, is pressurized to 2 atm. This pressurized gas effectively cushions shock and vibration loads, evenly distributing stress within the ball material and increasing its resistance to fatigue failure, extending its service life. The outer annular channel contains a viscous fluid—high-viscosity synthetic polyalphaolefin oil with a density of 800 kg / m3. 3 and a viscosity of 460 cSt, it provides viscous damping of high-frequency vibrations and inertial disturbances that occur during sudden changes in rotational speed, and also further reduces friction within the ball structure. The inner annular channel uses a heavy fluid—silicone oil with a tungsten carbide filler (60% by weight) and a density of 2000 kg / m3. 3With a viscosity of 550 cSt, this composition creates a significant gyroscopic moment, stabilizing the balls during rotation, actively counteracting torsional vibrations, and promoting efficient heat dissipation from the contact zone. Thermal expansion of the fluid in the channels is compensated for by the correct filling calculation, the low expansion coefficient of silicones, their thixotropic properties, and their high solids content.

[0015] Filling of the annular channels with liquid is calculated using the formula:

[0016]

[0017] where V is the volume of the annular channel, V зап - volume of actual filling of the annular channel, T max - maximum operating temperature, T зап - filling temperature, P цент - centrifugal pressure, ω - angular velocity, ρ - density of liquid in the annular channel, r внеш , r внут - outer and inner radius of the annular channel.

[0018] When the rotation speed changes, the fluid in channels 6 and 7 moves with a delay, creating a damping effect, in addition, when the bearing rotates, the movement of the fluid in channels 6 and 7 creates a gyroscopic moment, which can be calculated using the formula:

[0019]

[0020] where M is the gyroscopic moment acting on the rolling element (ball), ω s - angular velocity of the ball's own rotation, ω р - angular velocity of precession (rotation of the ball axis), θ - angle between the axis of proper rotation and the precession axis, for a rotation speed of 10,000 rpm, and a heavy liquid with a density of 2000 kg / m3 3 :

[0021]

[0022] F - stabilizing force, r - radius of the ball,

[0023] which stabilizes the position of balls 3 and counteracts external disturbances due to inertia. Central cavity 5 further softens impact loads, acting as an elastic element. Liquid-filled cavities 8, mounted on separator 4, actively dampen torsional vibrations, converting vibration energy into heat.

[0024] Compared with the prototype, the device effectively combines inertial, gyroscopic and viscous damping, which can significantly improve reliability, reduce vibration and increase the durability of the bearing under high-speed and high-load conditions.

[0025] Positive effect - the proposed device allows to increase the reliability and durability of the ball bearing by compensating for inertial disturbances, vibrations and torsional oscillations when operating in transient conditions at high speeds.

Claims

A ball bearing consisting of outer and inner rings, a separator and balls, characterized in that the ball has a gradient internal structure with a radially variable distribution of material density, a central cavity filled with gas, an outer annular channel located at the surface of the ball and filled with a viscous liquid, an inner annular channel located between the central cavity and the outer channel, filled with a heavy liquid, cavities with viscous liquid are installed on the separator between the balls and are rigidly connected to it.

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