SU113850A1 - Automatic die for making wire hollow rivets - Google Patents

Description

Automatic stamps for the manufacture of hollow rivets made of wire, with the arrangement of matrices around the circumference on the swivel head are known.

However, such stamps have low productivity due to the large number of transitions in the molding of the hollow part of the rivet. In addition, the sushi is known, and the geometry in the forming part of the die and punch does not provide the necessary durability, which leads to premature tool failure.

In the described automatic stamp these deficiencies are eliminated by applying a different design of dies and punches, which consists in the fact that the working surfaces of tools (dies and punches) are made conical. At that, the angle at the apex of the cone of the die is greater than performing intermediate operations of forming the inner part of the rivet.

FIG. 1 shows a stamp in longitudinal section; in fig. 2-view B of the plan (without the upper movable part); in fig. 3-scheme of technological transitions; in fig. 4 is a section along AA in FIG. 2

The stamp has a bottom plate 1, fixedly mounted on a press table, and an upper movable plate 2, which is rigidly attached to the press ram using the shank 3. A rotary head 5 is installed on the bottom plate / column 4, around which the die 6 is placed. 1, spring-loaded punches 7 are placed, which serve to form the head in the rivets and create elastic supports in the process of forming the rivet.

To rotate the head 5 at a certain angle, a ratchet wheel 8 is fixed on it, which interacts with the ratchet 9 (dog) fixed on the slider 10. The latter is placed in the slot of the plate), where

No. 113850-2 -

makes reciprocating motion. In addition to the ratchet 9, the following elements are fixed on the slider: bracket //, stand 12, carrying a carriage 13, and a roller 14 mounted on an axle.

A plate 15 with puncheon holders 16 and punches 17 is rigidly attached to the upper plate 2; the number of the latter corresponds to the number of transitions to form a hollow rivet.

To improve the flow conditions of the metal and reduce the number of transitions during the formation of the hollow part of the rivet, the working surface of the matrix 6 is made conical with an angle of 45 °; The working surface of the punches 17 is also made conical with an apex angle of 30 ° and on the next transition 20 °.

The ratchet drive for turning the head 5, as well as the wire feeder, is driven by a wedge 18 fixed in the upper plate 2. In the slot of the wedge 18, a roller 14 slides, telling the movement of the ratchet 9 and the carriage 13.

For measuring the length of the workpiece from the rod on the top plate 2 is rigidly fixed knife 19, which interacts with the cutting sleeve 20.

The work of the stamp is as follows.

When the working stroke of the press ram down the wedge 18 slanting groove presses the roller 14 and moves the slider 10 to the left; the ratchet 9, which engages with the ratchet wheel 8, rotates the head 5 together with the dies 6 by a certain angle, for example by 30 °. At the same time, the bracket // moves the carriage 13 by a step equal to the length of the rivet blank.

After that, the sleeves 21 and 22 with balls mounted into the carriage 13 are made by jamming the wire clamp while it stops against the stop 23. Then a wire of a certain length is cut with a knife. 19 The cut piece falls into the hopper 24, and it is turned at the last time it touches the pin. 25

When the press ram is reversed up, the ram 10 together with the ratchet 9 and the bracket // returns to its original position; swivel head 5 remains stationary.

At the first transition (see Fig. 3), the workpiece 26 is loaded with a spring-loaded punch 27 into the matrix 6. At the second transition, the workpiece enters the landing head. When working down the press slide, the punch holder presses on the end of the die, which moves down with the workpiece before meeting the punch 7; the workpiece settles to form the head of the rivet, and the punch U7 flares the end of the rivet.

When the press ram moves upwards, the sleeve 28 pushes the die to the level of the bottom plate under the action of the spring and removes the rivet head from the punch 7. With further rotation of the head 5, the rivet is transferred to the third transition together with the die - intermediate operation. Here, the punch 17 presses against the flared portion of the rivet and mixes the die together with the rivet down onto the support punch 7; when the head of the rivet touches the support punch, the matrix stops the downward movement, and the punch 17 produces a rivet opening. To prevent the rivets from being pushed out of the die by the punch 17, the column 4 compresses the spring 29 with some advance until the punch 17 B enters the work. Similar work is performed by the elongated punch 17 for the final emergence of the rivet hole at the fourth transition. Due to the difference in the corners (on the matrix, the angle is 45 °, and on the punches 30 ° and 20 °) when the hole is planted, the metal flows freely upwards into the widening slit, forming a funnel with thickened walls at the top of the funnel. When the rivet is pushed out by the last punch

the matrix with the cylindrical part folds the rivet funnel into the tube and draws the thickened walls of the funnel. When the press ram is reversed up, the rivet from the ejector punch is removed by the puller. thirty

Claims (2)

1. Automatic stamping for the manufacture of hollow wire rivets with dies placed around the rotary head, characterized in that, in order to increase productivity and improve metal flow conditions, the working surfaces of the die and punches are conical. 2. The form of the stamp according to claim 1, characterized in that the angle at the apex of the cone of the die is greater than the angle at the apex of the cone of the punches which perform intermediate operations of molding the internal cavity. - 3 - № 113850 Subject invention