RU1831409C - Faceted nuts production method - Google Patents

Abstract

Usage: metal forming, manufacturing techniques of polyhedral nuts. SUMMARY OF THE INVENTION: In the end surfaces of the preform, conical recesses with offset vertices are formed. The vertices of the recesses are displaced in opposite sides to each other. The outer surface of the preform is shaped in the shape of a polyhedron. The jumper formed between the two conical recesses is pierced. 7 ill.

Description

The invention relates to the processing of metals by pressure and can be used in the manufacture of parts such as polyhedral nuts by cold and hot stamping.

The purpose of the invention is to increase the durability of the heading tool.

This goal is achieved by the fact that by the method of manufacturing polyhedral nuts, including cutting a workpiece, the preliminary, final formation of the recesses under the hole with the bottom part in the shape of a cone, the design of the polyhedron and the subsequent flashing of the hole, when extruding at least one final recesses under the hole, the conical recess of the bottom the parts are made with a vertex offset relative to the axis of symmetry of the formed recess. In addition, the vertices of the cones of the recesses are offset relative to each other in a plane perpendicular to the axis of symmetry of the nut.

The displacement of the tops of the cones relative to the axis of symmetry of the formed recesses, as well as relative to each other, allows to increase the minimum thickness of the resulting bridge in the area of the tops of the cones, which leads to less hardening of the metal and, consequently, to a reduction in stamping forces (maximum local in the region of the peaks and the general) and increase tool life.

In FIG. 1 presents the workpiece; in FIG. 2 - detail after the 1st transition; in FIG. 3 - the same, after the Mth transition; in FIG. 4 - the same, after the Illth transition (the vertices of both conical recesses are displaced relative to the center of the base); in FIG. 5 is the same. after tV-ro transition; in FIG. 6 - location of the part and tool after stamping at the I-th transition; in FIG. 7 - embodiment of the part after the Illth transition (more00

with

i

H)

cx

relative to the center of the base, only one vertex of the conical recess).

At the i-th junction, blanking and chamfering are carried out on one side of the blank.

At the Pth junction, the polyhedron, recesses for the hole, and chamfers are preliminarily formed.

At the 111th transition - the final formation of the polyhedron, recesses for the hole and chamfers.

The vertices of both (or one) conical recesses are offset relative to the center of the base, and also relative to each other in a plane perpendicular to the axis of symmetry of the nut.

At the 4th transition, the hole is pierced.

The workpiece obtained at the transition is installed in the channel of the 111th operation matrix. Then, with the punch 2, resting on the ejector 3, the formation of the final recesses under the hole and the formation of the polyhedron are obtained, obtaining the workpiece 4 of the 111th operation (Fig. 6).

In this case, the conical recesses of the bottom part are extruded with a vertex 5 offset from the axis of symmetry 6 of the formed recess. This is achieved by using a punch 2 and an ejector 3 with a conical end surface, the apex of which is offset relative to the tool axis, which can be obtained both by parallel displacement of the symmetry axis of the conical surface relative to the tool symmetry axis, and by changing its angle of inclination to the tool axis. In addition, the vertices 5 of the conical surfaces are offset relative to each other in a plane perpendicular to the symmetry axis of the nut. This is achieved by turning the punch and the ejectors about their axis.

Example. The M-16 nuts were stamped according to GST 5915-70 according to the proposed method with a shift of the tops of the cones of the final recesses by 2.8 mm relative to the axis of the recesses, as well as relative to each other in a plane perpendicular to the axis

symmetry of the nut, at an angle of 180 °. Then, by replacing the punches and ejectors of the final stamping, the nuts were planted without shifting the tops of the cones. The nuts were planted on an AA 1822 machine from 10KP steel according to GOST 10702-78.

The volumes of the formed depressions by the known and proposed method are equal. Test results showed

10% increase in durability of punches and ejectors.

Using the proposed method in comparison with the prototype, in addition to increasing durability, provides the following

advantages. Creates the possibility of reducing metal when piercing the hole by increasing the volume of the final recesses. Allows to reduce the taking place due to distortion of the workpiece shape

when cutting and stamping, the ribs of the polyhedron are not uniformly filled without shifting the axis of the hole relative to the hexagon by changing the position of the punches and ejectors by rotation relative to the axes.

Formula A method for manufacturing polyhedral nuts, including cutting a workpiece, preliminary and final formation of recesses in the form of cones from the side of both end surfaces of the workpiece with the formation of a jumper, the design of the polyhedron, and also subsequent piercing of the jumper, characterized in that, in order to increase the tool life at the upset position by reducing the extrusion force, as well as at the firmware position due to the formation of the jumper

of minimum thickness, the surface of at least one recess is made in the form of a cone surface with a vertex offset from the center of the circumference of its base, with the vertices of the opposite conical recesses being displaced relative to each other in a plane perpendicular to the axis of symmetry of the nut.

Figure 1

FIG. 2

Fig.Z

FIG. 4

w

h and

Fig 5

FIG. 6