SU1340921A1 - Boring bar for machining deep holes - Google Patents

Abstract

The invention of otsits to metal cutting and can be used with a deep hole boring tool. The aim of the invention is to improve the processing accuracy of deep holes by increasing the efficiency of damping vibrations and torsional vibrations. Since during the cutting process on the boring bar, acting on the JOT changing cutting forces that cause its deformation and is of elastic nature, axial and torsional oscillations of the system arise. The resulting axial vibrations are extinguished with a transversely located elastic element 9 and partially elastic elements 14. The bending and torsional vibrations are extinguished by mainly elastic elements 14 and partially elastic elements 9. 5 Il. (L F4 / city /

Description

The invention relates to the operation of metals by cutting and can be used when bore deep holes.

The aim of the invention is to improve the processing accuracy of deep holes by increasing the efficiency of damping vibrations and torsional vibrations.

FIG. 1 shows a boring bar, general view; FIG. 2 is a cross section A-A in FIG. one; FIG. 3 - VI, B in FIG. one; in fig. 4 - scheme of damped oscillations; in fig. 5 - elastic element.

Boring bar consists of two concentrically arranged pipes 1 and 2, rigidly connected to each other at one end by sleeve 3. At the free end of pipe 1, a cutting tool 4 is installed. Pipes 1 and 2 are connected along a sliding fit. On cylindrical surfaces 5 and 6 of these pipes, steps 7 and 8 are provided, which form a cavity closed on all sides, filled with an elastic element 9 of length L and thickness S 5 intended for damping axial and bending vibrations.

On the outer surface 6 of the tube 1 there are petals 10, between which petals 11 flourish, so that between the side surfaces 12 of the petals 11 and the side surfaces 13 of the petals 10, gaps are formed in which the elastic elements 14 are spaced.

The lateral surfaces of the petals and the lateral surfaces 15 of the elastic elements 14 are made in the form of a monotroped curve, which decreases along the boring axis, for example, according to the law of damped oscillations

-S- t

R

where a is the amplitude of damped oscillations;

a is the amplitude, in the beginning; the main moment of oscillation,

1 - constant value;

l is the logarithmic decrement of damping;

T is the period of damped oscillations;

t is the oscillation time.

Boring bar for machining deep holes, comprising a body made of at least two end-of-three arranged pipes rigidly connected to each other at one end, and elastic elements placed in longitudinal cavities formed on the mating surfaces

55 pipes, characterized by the fact that Borshtang works as follows: in order to increase the accuracy of the working, the boring bars are equipped with an additional oscillation element arising from the axial elastic element, and the oscillations are quenched. transversely transverse in transverse annular polypositional elastic element 9 and partially elastic elements -14.

The bending and torsional vibrations are extinguished by mainly elastic elements 14 and partially elastic element 9.

When cutting on the boring bar, there are cutting forces. As various factors influence, these forces vary dramatically in magnitude, which causes deformation of the boring elements. The deformation forces are elastic and cause the cutting element to oscillate. Fluctuations from the cutting tool are transmitted to pipe 1, which in turn, through surfaces 6 and 8, transfers them to the elastic element 9. The successor compresses c in a closed volume and damps vibrations by absorbing vibrational energy. Partially axial vibrations transferred to resilient elements 14, which, when compressed, extinguish them.

When occurring on the cutting element. 5, the torsional vibrations from the tangential component of the cutting force are transmitted to the pipe 1, then through the side surfaces 13 to the elastic elements 14, which, Q, squeeze in a closed volume, extinguish them,

Where there are oscillations, they are damped by their length, i.e. their amplitude varies along the length of the elastic element 14. A certain magnitude of the amplitude for a certain material of the elastic element corresponds to a certain size A of this element. Such an element makes it possible to carry out vibration damping in the best possible way, since this size is optimal. Since the amplitude along the length of the vibration-suppressing element decreases, so must the size A also be reduced along a monotonically decreasing curve.

five

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Formula of invention

Boring bar for machining deep holes, comprising a body made of at least two ends of three arranged pipes rigidly connected to each other at one end, and elastic elements placed in longitudinal cavities formed on the mating surfaces

31340921

These pipes are made on the pipes on the pipes, the lateral surfaces of the pipes and are bounded on all sides, and the longitudinal cavities are formed by petals that have a monotonically curving shape in cross section

the surface of the petals and elastic elements in the cross section has the shape of a monotonically decreasing curve along the boring bar axis.

eleven

13

ten

FIG 2

Buff in

/ 4 1lf 15 / I I

fuy. J

Uz

FIG. five

Compiled by S. Ber Editor N. Shvyschka Tehred M. Didyk

Order 4385/17 Circulation 974 Subscription

VNIZhSH State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab. 4./5

Production and printing company, Uzhgorod, st. Project, 4

Proofreader E.Roshko

Claims (1)

Claim A boring bar for processing deep holes, comprising a housing made of at least two concentrically arranged pipes rigidly interconnected at one end and elastic elements placed in longitudinal cavities formed on the mating surfaces of the pipes, characterized in that, in order to increase precision machining, the boring bar is equipped with an additional -elastic element mounted in the transverse annular strip, which is made on the mating surfaces of the pipes and bounded by them on all sides, and the longitudinal floor the spans are formed by petals that are made on the pipes, and the lateral surface of the petals and elastic elements in the section has the shape of a curve monotonically decreasing along the axis of the boring bar. Aa View 5 Fig.Z 1.340921 FIG. 4 FIG. 5