RU1789798C - Bearing assembly - Google Patents

Abstract

Usage: mechanical engineering, mainly machine tool. SUMMARY OF THE INVENTION: The housing is secured in the headstock of the machine. The shaft rotates on rolling bearings having preload by means of assembly springs. Between the outer and inner rings of the front bearing assembly, spacer sleeves are installed, the ends of which are provided with corrugations. During rotation, the bearings heat up, and their inner and outer rings expand in both radial and axial directions. The spacer rings in the linear direction are able to be compressed due to the corrugations, therefore, in the radial direction, the initial radial clearance in the bearings does not change and the radial expansion is compensated by the linear. 3 ill.

Description

The invention relates to mechanical engineering, mainly to machine tool engineering, and can be used in the manufacture of high-speed spindles, surface treatment machines, for example, bearing rings.

An electrospindle for grinding is known, including a housing, a rotor with a grinding mandrel and a pulley, bearings with spacer sleeves, a preload device, which is taken as a prototype.

A drawback of this embodiment of the bearing assembly is that if the front bearings are overheated, the outer and inner rings tend to expand linearly, and since they are fixed in the axial direction, they radially expand. As a result, the permissible radial clearance is reduced, which

leads to jamming of bearings and their premature failure.

The aim of the invention is to increase the operability of the bearing assembly and to provide increased reliability of the device.

This goal is achieved in that the bearing assembly of the front bearing, consisting, for example, of duplexed bearings, is provided with spacer sleeves installed between the outer and inner bearings in axial direction with corrugations (wave-shaped folds) having between the housing and shaft seating surfaces a gap exceeding the temperature-linear displacement by no more than two times, and the stiffness of these spacer sleeves f is with the stiffness fi of the bearing assembly from pre ritelnogo tension ha ratio f 10fi. The presence of the specified gap is required (L

G

VI 00

che

Xi

U 00

to prevent wrinkles from jamming during heating or cooling after the end of the rotation of the shaft.

Figure 1 shows the proposed bearing assembly, General view; figure 2 and 3 - node I and II in figure 1.

The bearing assembly consists of a housing 1, a shaft 2 on rolling bearings 3, where in the front support between the outer and inner rings of the bearings there are laid corrugated bushings 4 and 5, at the ends of which there are wave-shaped folds (Figs. 2 and 3 are shown in enlarged view), and preload unit 6.

The proposed bearing assembly operates as follows.

The housing 1 is fixed in the headstock of the machine, the shaft 2 rotates on rolling bearings 3 having preload by means of the springs of the preload unit 6.

Between the outer and inner rings of the front bearing assembly, spacer sleeves 4 and 5 are installed, the ends of which are provided with corrugations, the design of which is shown in Figs. 2 and 3. During rotation, the bearings heat up, and their inner and outer rings expand both radially and axial direction, since the spacer rings 4 and 5 in the linear direction are able to be compressed due to the corrugations, there will be no change in the radial direction

0

5

0

5

0

the initial radial clearance in the bearings and compensation of the radial expansion due to linear, because resizing the node as a whole will go along the line of least resistance, i.e. in a linear direction.

When developing the design of the grinding wheel drive with a rotation frequency from 12000 to 18000, the bearing 4-36210E was used, and the spacer rings had the following parameters:

a) 0 90 mm; 01 89.5mm; 02 86.1 mm; Oz 84.1 mm;

t 1 mm; h 1.5 mm;

b) d 50 mm; eh 50.5 mm; da 59.8 mm; d3 61.8.MM.

Experimental studies of the proposed bearing assembly with temperature-compensating elements have shown that, compared with the prototype device, the proposed device is more reliable in operation and thereby improves the resistance of high-speed electrospindles by at least 2 times. The economic effect of the implementation of the claimed device was obtained due to a reduction in the cost of acquiring an additional number of electric spindles necessary to ensure the operation of the machines when they are replaced in the event of failure and to reduce the cost of installation and commissioning repairs.

Claims (1)

SUMMARY OF THE INVENTION A bearing assembly comprising a housing and a pair of rolling bearings installed in it and on the shaft with axial preload spacers between their inner and outer rings, characterized in that, in order to increase durability and reliability, each spacer sleeve fulfill- partially on the side of one of the ends of the corrugated in the axial direction with a diameter smaller than the diameter of the bore of the housing or larger than the diameter of the shaft, respectively, by an amount exceeding the value of their temperature displacement, and the stiffness of each sleeve is greater than or equal to the stiffness of the assembly from the preload force. Figure 2 Fig.Z