SU1024192A1 - Tap - Google Patents

Abstract

A METER containing a shank and a working part within which a cylindrical bore is made, characterized in that, in order to improve the quality of the thread obtained and improve performance, the angular groove is formed along the entire length of the working part of the tap, forming an internal cavity with a cylindrical bore, the axis of which is located eccentric relative to the axis of the tap and lies in the plane of symmetry of the angular groove

Description

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The invention relates to metal working.

A known design of a tap for processing blind holes with an internal chip outlet, comprising a shank, a rod-shaped working part with a cylinder cavity inside, the cavity being an expanding inner cone that passes upward into the hole for chip chips 1.

The disadvantage of the tap is that the forming chips do not fall into the conical hole, since the bases of the chip grooves are perpendicular to the tool axis. The forming chips fall into the hole being machined and under the thread profile, which leads to breakage of the tap. The threaded part is cylindrical without backing up and a reverse cone, which leads to an increase in torque, jamming and breakage of the tool. In addition, a disadvantage is the difficulty of manufacturing due to the presence of internal obverse conical holes.

The purpose of the invention is to improve the quality of the obtained thread and improve the performance of the tap.

This goal is achieved by the fact that in the tap containing the shank and the working part within which the hole is made, and in the intake section of the working part - groove, along the entire length of the working part of the tap, an angular groove is formed, forming an internal cavity with a cylindrical hole, the axis of which is eccentric relative to the axis of the tap and lies in the plane of symmetry of the corner groove.

FIG. 1 shows the design of the tap; in fig. 2 is a section A-A in FIG. one; in fig. 3 is a scheme for forming a threaded profile with a tap.

The tap contains a shank 1 and a working part 2.

The entire length of the working part 2 is made of an angular groove CJ, forming an internal cavity with a cylindrical hole

doTB, whose ocb is located eccentrically to the axis of the tap (f is eccentricity) and lies in the plane of symmetry of the corner groove.

Thus, a plastically deforming 3 and cutting 4 areas are formed on the working part.

The tap works in the same way. The taps are reported rotation and axial movement. Alternately, the plastically deforming 3 and 4 cutting sections of the intake and calibrating parts come into play, carried out the combined process of forming a threaded profile in the hole being machined by plastic deformation (SiS3, Ss S) and

5 by chip removal (52845683).

When using the proposed tap, the quality of the threads obtained is improved, as there is a combined process of forming internal threads. Tap performance improves,

 Since the processing of difficult-to-cut materials in the event of a sharp increase in the cutting force results in elastic deformation of the cutting section 4 of a relatively thin section of the working part

5 in the opposite direction of rotation. This reduces the size of the rake angle, which increases the strength of the teeth of the cutting section 4.

Similarly, the elastic deformation of the section 3 towards the hole axis increases

0 wear resistance of the teeth of the plastically deforming section 3. The tap is easy to manufacture, since complex equipment and adjustments are not required to form a cylindrical hole and an angular groove. Varya the size of the diameter of the holes

 doTb. it is possible to provide the necessary amount of deflection of the cutting section 4 when unscrewing, as a result of which section 3 can clean up (finish operation) the formed profile. This

0 the same diameter sets the required amount of deformation to the cutting section 4 when screwing the tap into the hole being machined.

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Claims (1)

TAPER containing a shank and a working part, inside which a cylindrical hole is made, characterized in that, in order to improve the quality of the obtained thread and improve performance, an angular groove is made along the entire length of the working part of the tap, forming an internal cavity with a cylindrical hole, the axis of which is eccentrically placed relative to the axis of the tap and lies in the plane of symmetry of the angular groove A 'fi & .1