SU1585128A1 - Spindle for metal-cutting machine - Google Patents

Abstract

The invention relates to mechanical engineering and can be used in precision machine tools. The purpose of the invention is to increase the durability of the spindle of the metal cutting machine through the rational distribution of elastic axial tension in the supports. The cutting machine spindle includes a housing 1, a front 4 and a rear 5 supports, each of which includes two angular contact ball bearings, a shaft 3 and axial tension means, made in the form of spacer elements 11, 17, made in the form of a set of identical cylindrical rings. On one end surface of the ring two protrusions are evenly spaced circumferentially, on the other end surface there are two grooves symmetrically arranged between the protrusions. The spacer element 11 of the front support is installed on its inner side, the spacer element 17 of the rear support is installed between the bearings of this support. The rational distribution of elastic axial tension in the front and rear supports is ensured by the structural dimensions of the spindle. 5 il.

Description

(21) 4443972 / 31-08

(22) 20.06.88

(46) 08/15/90. Bksh. No. 30

(71) Institute of problems of reliability and durability of machines of the Academy of Sciences of the BSSR

(72) N.T. Minchen, P.A. Udavidchik, S.I. Chernykh and I.A. Kyopichenko

(53) 621.923.5 (088.8).

(56) Lizarditsin G.I. and Karaim I.P. High-speed intra-pinning spindles on rolling bearings. - Science and technology, 1979, p. 81, fig. 2.1.

(54) SPINDLE OF METAL CUTTING MACHINE

(57) The invention relates to mechanical engineering and can be used in precision machines. The purpose of the invention is to increase the durability of the spindle of the metal cutting machine through the rational distribution of elastic axial tension in the supports. The spindle of the metal-cutting machine includes a housing 1, a front 4 and a rear 5 supports, each of which includes two radial-stop ball bearings, a shaft 3, and axial tension means, made in the form of spacer elements 11 and 17, made in the form of a set of identical cylindrical rings . On one end surface of the ring two protrusions are evenly spaced circumferentially, on the other end surface there are two grooves symmetrically arranged between the protrusions. The spacer element 11 of the front support is installed on its inner side, the spacer element 17 of the rear support is installed between the bearings of this support. The rational distribution of elastic axial tension in the front and rear supports is ensured by the structural dimensions of the spindle. 5 il.

i

(L

22 9 21 1 12 1 6

m.-fog

ate

00

ate

N9 00

15

. Zhg n ost

1

The invention relates to a machine tool industry and can be used primarily in precision machine tools.

The aim of the invention is to increase the accuracy of the durability of the spindle.

FIG. Figure 1 shows the spindle of the metal-cutting machine; general view; in fig. 2 - spacer, view assembled; in fig. 3 - cylindrical ring; in fig. 4 - spacer retainer; in fig. 5 is a spindle design diagram.

The spindle of the metal-cutting machine includes a housing 1 (FIG. 1), in which the stator winding 2 is fixed, the shaft-rotor 3, angular contact ball bearings 4 and 5 fixed on the shaft 3, the inner bearings 6 of the front bearing are fixed to the shaft 7 and the intermediate ring 8, and the outer ones are installed in the cover 9 and secured therein by means of a nut 10, a spacer element 11 and a flange 12. Installing bearings 4 in the front support in a back-to-back scheme allows bearing support in both directions. The inner rings 13 of the ball bearings 5 of the rear bearing are fixed to the shaft 3 by means of a nut 14 and an intermediate ring 15 “The outer rings of these ball bearings are mounted in the cover 16 and are axially floating. To create a preliminary axial tension in the bearings 5 rear support. A spacer element 17 is installed between their outer rings. The spacer elements 11 and 17 are designed as a set of identical cylindrical rings.

18 (FIG. 2), on one of the end surfaces of which two protrusions 199 are evenly circumferentially distributed on the other end surface — two grooves 20 (FIG. 3), arranged symmetrically between the projections 19. The grooves

20 serve to fix the rings 18 one to the other. Protrusion height

19 is greater than the depth of the grooves 20 by an amount exceeding the maximum elastic deformation of the cylindrical ring 18 after it has been installed in the spacer elements 11 and 17. To lock the spacer elements 11 and 17 in the lids 9

and 16 serve two clamps 21 (Fig. 4) installed in the slots 22. Lubrication under

ten

55

51284

dog dogs 4 and 5 are made by shallow mist supplied through fitting 23 fixed in the lid 24, and cooling of housing 1 by liquid supplied through fitting 25. To lock the nut 10 in the cover 9 serves latch 26. In FIG. Figure 5 shows the design scheme of the spindle of the metal-cutting machine, where 1 is the distance between the supports 4 and 5 (span), m; a - spindle vypet,

m;

P is the cutting force, N; Rn, R3 - reactions in the supports, N.

c - P (a + 1) RnГ

R th

R3- G

Since the amount of wear of the supports is proportional to their load ™, the forces of the preliminary axial tension should be related by the relation:

Fn

F3

a + 1 a

0

five

0

0

five

0

FIJ

F3

 about sre

 f3 Sre,

n;

n;

where fl and f h are the indicators in the front and

rear supports, respectively, m;

With RZ - axial stiffness of the spacer, N / m.

From here

f l and + 1

f; - Spindle metal cutting machine works as follows.

In the process of preparing the spindle for operation with the help of the nut 14 and the wheel 15, the required amount of preliminary axial tension in the bearings 5 of the rear support is set, the tension value is equal to the difference in length of the spacer element 17 in the assembled undeformed state and the wheel 15. Thereafter taking into account the design parameters of the electric spindle (a and 1), the size of the preliminary axial tension of the bearings of the front support is determined.

f - f a + l fn - VT

After that, screw the nut 10 into the cover 9, set the axial tension g

Claims (1)

Invention Formula Spindle metal cutting machine, comprising a housing, front and rear supports, including at least two angular contact ball bearings, a shaft and axial tension means, made in the form of spacer elements, characterized in that 20 f. . 5g five where fft and f3 are tension in the front and rear support legs, respectively; distance between spindle supports, m; distance from the spindle nose to the front support, m 1 and G9 FIG. 2 18 ,,-at Figz Figm 5