SU1364400A1 - Method and apparatus for boring holes - Google Patents

Abstract

The invention relates to the field of machining of metals, mainly to the finishing of holes on a multi-purpose machine with boring bars with automatic radial movement of the tool. The purpose of the invention is to increase productivity by eliminating their technological process of the probe inserted into the spindle instead of the tool. In the spindle 1 of a multi-purpose machine, a magnetostrictive boring mandrel with corus 2 and shank 3 is installed. The end of body 2 is made calibrated. On the case 2

Description

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magnetostrictive element 5 is deposited and cutter 6 is installed. The casing plays the role of a magnetic board. One lead of coil 7 is connected to housing 2 and the other to shank 3. When the calibrated part of the mandrel contacts the surface of the machined hole, the electrical circuit closes: control unit — satellite — part — mandrel body — electromagnet coil — mandrel shank — spindle — bed — block management The current supplied to the electromagnetic coil creates a magnetic field in which the nickel from which the magnetostrictive element is made, changes its dimensions by such a small amount that

The invention relates to the machining of metals, mainly to finishing machining of multipurpose machin- ers with spreading mandrels with automatic radial movement of the tool.

The purpose of the invention is to increase productivity by eliminating from the process a measuring probe inserted into the spindle instead of a tool.

FIG. Figure 1 shows schematically a device for boring holes during the preliminary boring process of holes; in fig. 2 - device when measuring a pre-bore hole; in fig. 3 - the device in the process of final processing of the hole.

In the spindle 1 of a multi-purpose machine, a magnetostriction boring mandrel with body 2 and shank 3 is installed. The end of body 2 is made calibrated. An electrically insulating gasket 4 is installed between body 2 and shank 3. Magnetostrictive element 5 is deposited on body 2 and cutter 6 is installed. Magnetic coil 7 is installed at length of magnetostrictive element 5, covered by a casing consisting of a cylinder 8 and two covers 9 and ten.

the deflection of the mandrel is practically absent. The CNC system of the machine fixes the contact by the flow of current in the circuit of the electromagnetic coil and gives the command to move the mandrel to the lowest position. Before the mandrel contacts the hole surface, while measuring the path traveled by the mandrel between two contacts. The diameter of the hole is equal to the sum of the path traveled by the mandrel and the diameter of the calibrated portion of the mandrel. The CNC system commands the control unit to supply a current of the value corresponding to the required radial displacement of the tool. Then a hole is bored. 2 sec. f-ly, 3 ill.

The casing plays the role of a magnetic circuit. One lead of coil 7 is connected to body 2, and the other to shank 3. Work piece 11 is fixed to satellite 12. Electrically insulating pad 4 is made between satellite 12 and machine table 13. One end control unit 15 is connected to satellite 12 and the other end bed 16 machine.

The method is carried out as follows.

Upon contact of the calibrated part of the mandrel with the surface of the machined hole (Fig. 2), the electrical circuit closes; control unit — satellite — part — mandrel body — electromagnetic coil — mandrel shank — spindle — bed — control unit (shown by dotted lines). The current supplied to the electromagnetic coil creates a magnetic field in which the nickel, from which the magnetostriction element is made, changes its dimensions by such a small amount that there is practically no deflection of the mandrel. The magnitude of the current I is determined by the formula

4S2l2

I B; with r 2Sa (D2- d) W (B |. + d) 1b

fW - DD

WITH

3.3-10

-five

(li

la

L) 2

- the number of turns of the electromagnetic coil;

 length of magnetostriction element, mm;

 cross-sectional area of the magnetostrictive element, mm;

- the diameter of the mandrel along the length of the magnetostrictive element, mm;

- outer diameter of the cylinder

electromagnetic coil housing, mm;

БЗ - internal diameter of the cylinder housing of the electromagnetic coil, mm; Ij - the thickness of the cover of the casing of the electromagnetic coil, mm; 1 - the length of the mandrel from the cutting element to the maximum diameter of the shank cone, mm;

B is a coefficient depending on the physical properties of the magnetostrictive material,

and the current is supplied to adjust the radial position of the cutting element through the cutting zone.

The CNC system of the machine fixes the contact through the flow of current in the circuit of the electromagnetic coil and gives the command to move the mandrel to the lowest position before the mandrel makes contact with the - hole surface, while measuring the path traveled by the mandrel between two contacts. The diameter of the hole is equal to the sum of the path traveled by the mandrel and the diameter of the calibrated portion of the mandrel. The CNC system commands the control unit to supply a current with a value corresponding to the required

to the diagonal movement of the cutter, the hole is bored.

Then

The machined hole is measured again by the mandrel.

Claims (2)

1. A method of boring holes, which includes setting the cutting element of a magnetostrictive boring mandrel to the size outside the machine, measuring a pre-machined hole 1364400 ti, installing a magnetostrictive boring mandrel in the machine spindle and adjusting the radial position of the cutting element by changing the current in the electromagnetic coil 0 mandrels, characterized in that, in order to increase productivity, a pre-machined orifice is measured by injecting current into a boring mandrel coil, the amount of current I being determined by the formula BC five one where C 0 5 (1+ 25 (Pa - d) 4Sal2 V W 5G (Ba + d) lj (D. -D |)) 3.3 ten  f: if / IT  0717 W is the number of turns of the electromagnetic coil; length of magnetostriction element, mm; cross-sectional area of the magnetostrictive element, mm2; the diameter of the mandrel along the length of the magnetostriction element, - mm: ЧS2 d D. electromagnetic cylinder casing outer diameter D, 2 - the inner diameter of the cylinder housing of the electromagnetic coil, mm; la, - thickness of the cover of the electromagnetic coil housing, mm; 1 - the length of the mandrel from the cutting element to the maximum diameter of the shank cone, mm; B - coefficient is dependent on the physical properties of the magnetostrictive material, and the current is supplied for adjusting the pit, the turning position of the cutting element through the cutting zone. 2. Device for boring from-. Versions on a multi-purpose machine, including a magnetostrictive boring mandrel, comprising a housing with an electromagnetic coil placed on it, and a shank, as well as a control unit, characterized by the fact that, to increase productivity, a shim is installed between the shank and the mandrel body, and one of the terminals of the electromagnetic coil is connected with the shank, and the other with the frame of the mandrel. sixteen Fi2.g /