SU764801A1 - Automatic machine for making springs with one end bent inward - Google Patents

Description

The holder 14 is connected with a rotatable shoulder 16, hingedly fixed on the frame 1, and pressed against the finger 11 of the slider 10 by a spring 17. The high-speed shaft 7 is kinematically connected with two drive shafts 13 and 18.

At the end of the drive shaft 13 is mounted a feed roller 19, interacting with a feed roller 20 mounted on the drive shaft 18 with a spring loaded spring 21.

On the frame 1 mounted spring winding mechanism 22, which contains a special mandrel 23, a thrust pin 24 and a step foot 25.

The winding mechanism 22 is from the cutting device 26 at a distance (t) that provides for the deformation of the spring body in the process of cutting within the elastic deformation.

The cutting device 16, which has an accelerated cutting mechanism, consists of a holder 27, inside which, by means of bolts 28, a fixed mandrel-knife 29 is fixed with a helical groove 30, designed to orient the spring coil in the cut-off zone. ,,

The screw groove 30 of the mandrel-knife 29 has a rounded edge 31 and a cutting edge 32 on the last turn, which are intended to simultaneously hem the end of the coil of the previous spring and cut off the finished product.

The machine works as follows.

The wire 4 is fed into the mechanism of Yoshvivka 22 by means of the feed rollers 19 and 20, where it is formed into a spring of the required length.

This length consists of a permanently wound part 8 and a cutting part equal to the length of the finished spring. Constantly wound part 2 corresponds to the distance at which the coiling mechanism spring 22 and cutting device 26 are spaced apart from each other.

The distance is determined by pho. mule

about 560 Mp t, o

p 1C15 pr

where within elastic deformations

.bS CHZS; o

K-10

chr

, e

then we get;

like t

2.NniKS-10 min iCD LGH-ilC.

if.p is the unwinding angle;

UE wire feed speed, t is the time of cutting the finished product;

o average spring diameter;

4 ° is the maximum allowable unwinding angle;

i is the number of steps of a permanently wound part of the springs;

S - spring pitch;

K - coefficient of curvature

(С - spring index (С Do / d}

d is the diameter of the wire; I6nil is the allowable bending stress.

Before the zone, sections of the spring are constantly wound, a part of the spring passes through the screw groove 30 of the fixed mandrel-knife 29. In one turn, the rollers 19 and 20 give out the length of the wire required by the casing of the single spring. The navita spring is cut off by the movable knife 15, which under its own motion bends the remaining end of the previous spring with the help of the rounded edge 31 of the fixed mandrel-knife 29. The movement of the movable knife 15 along the section and the spring of the spring is carried out by the interaction of the impact cam 8 mounted on the high-speed shaft 7, s roller 9 slider 10, located on the carrier 12 of the drive shaft 13, the finger 11 of which moves the holder 14 of the movable knife 15. The return of the movable knife 15 is carried out by means of the spring 17.

The ratio of the speed of the high-speed shaft to the drive shaft can be taken, for example, 4, and depending on this, the impact cam 8 is calculated.

Claims (1)

1. USSR author's certificate No. 420371, cl., B 21 F 3/04, 1971.. I tj g zt zi th 11 IS