SU1516207A1 - Screw tap - Google Patents

Abstract

The invention relates to the processing of metals by pressure and can be used in the manufacture of taps to produce threads in brittle and low-ductile materials. The purpose of the invention is to improve the quality of the obtained thread. On the working part of the tap, feathers are made with teeth, on which cutting sections with a constant amount of backing along the thread profile and plastically deforming sections having a radius shape along the entire profile height are placed. Plastically deforming areas are located directly behind the cutting areas. During the direct stroke of the tap, the cutting areas of the teeth cut a helical groove in the metal, and the plastically deforming sections smooth the sides of the profile, thus playing the role of guide elements. During processing, the plastically deforming sections prevent cutting the thread profile and breaking it along the average diameter. This makes it possible to increase the accuracy of the threads produced. 3 il.

Description

The invention relates to the processing of metals by pressure and can be used in the manufacture of brooms for semi-scientific research institutes of threads in brittle and low-ductile materials.

1 (1, 1 of the invention is to increase the quality of the radiated thread by eliminating the cutting of the sides of the profile.

FIG. 1 shows a tap, general view; H2 of FIG. 2 is a section A-A in FIG. one; in fig. 3 - section BB in FIG. 2

The tap contains the working part 1 and the shank 2. On the working part of the tap are made feathers 3. Each feather in the arc section (Fig. 3) has cutting sections 4 and plastically deforming sections 5. Sections 5 have a radius shape of the lateral working surfaces along the entire height of the thread profile . Sections 5 are mixed across the width of the pen to the front cutting face 6 formed by the chip groove. The distance 1 from the middle of the plastically de-fopMnpyK: nwx sections to the front cutting to the cuff 6 is less than one third of the width of the width F.

The cutting sections 4 are made ground by the K value along the thread profile and their side cutting edges are made ground by the Kp value relative to the radial side surfaces of the plastically deforming sections 5. Moreover, the backing value Ki is constant over the entire width of the cutting areas.

LAETCHIK works as follows.

During the forward stroke, the cutting sections of the teeth of the intake cone of the tap begin to cut a helical groove in the metal. Plastically deforming sections located directly behind the front cutting edge begin to deform the lateral sides of the thread groove profile, since these sections have a width excess with respect to the side cutting edges by the RR value. Since the KP values are small (for MZ-M48 taps, they are in the range of 0.01-0.1 mm), sections 5 smooth more smoothly than plastically deform the sides of the profile, basically playing the role of a direction (L

with:

ate

05

Yu

about

lUH.x elements. Since sections 5 are located infrequently behind cutting sections 4, they prevent the profile from being cropped and broken according to the average diameter already from the first turns. Gradually move forward, the teeth of the intake cone of the tap deepen and expand the helical groove. The tooth of the gage part finally forms the thread profile. When reversed, the tap is turned out of the machined hole.

The presence of plastically deforming areas on the taps, which are located immediately behind the cutting areas, which have a constant amount of plugging, provides for regrindings of taps along the front cutting edges c. 1K) In the case of a stable production of high-quality threads, since the inevitable difference after sharpening does not affect the work of the broomsmen due to the constant amount of backing. The execution of plastically deformed sections of the markers with a radius along the entire height of the thread profile ensures that xoponiee guides them in the threaded cap, prevents the

threads on the average diameter, reduces the effort in obtaining the thread (the radius of the sides of the plastically deforming sections for each case can be obtained with the minimum necessary), reduces the roughness of the thread profile, etc.

Claims (1)

Invention Formula ten A tap containing a plastically deforming-forming section and a cutting section with a front cutting edge formed by a threading profile, both sections 15 being located on each tooth consistently across the width of the tap pen, characterized in that, in order to improve the quality of the obtained thread by eliminating the cutting of the sides of the profile, the cutting section is made with a constant amount of backing, and the plastically deforming forming section is made of a radius shape over the entire height of the profile, and e from the front cutting edge to plastically deforming the middle portion is less than one third of the width of the pen. 20 Ng FIG. f Bb ig.Z