SU925543A1 - Pressure die casting injection mould - Google Patents

Description

(54) PRESS FORM FOR MOLDING UNDER PRESSURE

one

The invention relates to the field of foundry, in particular to injection molding.

A known mold comprising a fixed and sweeping plate in which a punch plate is installed, an ejector plate with knives for cutting sprues and a sprue removing device containing a slider housed in the punch plate and an inclined column cooperating with it. In the woven plate, there is a fixed insert made with a runner of the gating system. To ensure that the gate is removed from the slider and the insert in the slider, a recess is made for the casting residue, and a tilted column is installed in the pusher plate (1. When the mold is opened, the finished casting is ejected from the mold and the blades of the casting are cut off by an edge at the same time.

The disadvantage of this mold is the complexity of the device for extracting the sprue from the fixed insert.

Also known is a mold comprising a fixed half-mold and a movable one, in which a punch plate, an intermediate plate, an ejector plate with knives and ejectors for cutting and removing sprues and an insert are installed,

fixed in the plate of the punch and having a channel for the feeder gating system 2.

This mold is the closest to the invention in its technical essence and the result achieved.

The main disadvantage of it is the complexity of the device for separating the sprue, which, in addition to the fixed insert, includes a sign fixed in the intermediate plate and complication of the mold due to the presence of springs of movement of the punch plate and spring-loaded latches.

The aim of the invention is to simplify the design.

Pel is achieved by the fact that, in the proposed mold for injection molding, containing a fixed half-form and a movable one in which a punch plate, an ejector plate with knives and ejectors for cutting and removing liters and an insert fixed in the punch plate and having the channel for the runner feeder system, the channel surface for the feeder in the insert from the ejector side of the gate is made along the radius: the center of which is on the intersection line of the inner surface of the channel for the feeder, located zhennoy opposite the sprue ejector, with the outer surface of the insert, raspolol ennoy from the sprue ejector, and said radius is defined by the relation

,

where r is the channel radius for

feeder;

h is the feeder channel thickness; b is the thickness of the insert.

FIG. i depicts the proposed mold, the moment of pressing, cut; in fig. 2 - the same, the moment of removal of the casting, sprue and washer; in fig. 3 is a scheme for removing lithics when performing the surface of the insert channel along a radius; in fig. 4 shows section A-A in FIG. 3; in fig. 5 is a section BB in FIG. 3; on fng. 6 shows the removal of the gate when the surface of the channel of insertion is but tangential to the radius.

Lress-form includes fixed and movable half-form. Mobile noloform contains plate 1 of fastening, plate 2 of pushers with counter-pusher 3 and pushers 4 and 5, respectively, of sprues and washers, stop plate 6, plate 7 of punch, insert 8, base plate 9. Insert 8 and fixed inserts 10 and 11, forming the working cavity of the mold together with the liner 8. In the inserts there are channels 12 connected to the feeder and washer of the gating system, the tops of which from the side of the ejector of the sprue and the washer are made along the radius or tangential to it.

In the slab 2, knives 13 and 14 are fixed to trim the sprues and eject the casting.

The fixed half-form contains a fastening plate 15, a matrix plate 16 with an insert 17 and a sprue bushing 18.

Mold for injection molding works as follows.

After pressing in the metal and holding it, the mold is opened. The casting, the sprue 19 and the scrubbing 20 move along with the movable half-form. The hydraulic pusher of the machine (not shown), rigidly fastened to the support plate 6 and the plate of 2 ejectors, moves these plates to the right. In this case, the knives 13 and 14 carry out the ejection of the casting and the cutting of the sprue and washer, which are fixed with inserts Yu and 11.

Simultaneously with ejection of the ejector pushers 4 and b, the sprue and washer are removed from inserts 10 and I. The possibility of removing the sprue and rinsing from the inner channels of the inserts is ensured by the yuan surface of the inserts being made from the ejector side of the sprue and washer by radius or tangent as shown in fig. 3 and 6. The radius, which is equal to or greater than the insert thickness, makes it possible to turn the sprues relative to point B, thereby allowing the ejector 4 and 5 to remove them from the insertion channels. In the case of manufacturing on a tangent, the same thing happens (see Fig. 6). Under the action of its own weight, the sprues and washers fall down into the machine pan. During the return stroke of the hydraulic pusher of the ejection surface, the | PYA system of the mold is moved to the left and takes the initial

position. When this occurs, the ejector plots detach from the casting due to the fact that the signs and fixed inserts 10 and I. prevent the movement of the casting to the left. The casting falls down into the tray of the machine.

The proposed mold has a simpler design of the device for casting removal, which increases its reliability in operation and reduces the cost of manufacture. In addition, the presence of a washer

provides better castings.

Claims (2)

1. A pressure die casting mold containing a fixed half-mold and a movable one in which a punch plate is installed, an ejector plate with knives and ejectors for trimming and removing sprues and an insert fixedly mounted in the punch plate and having a channel for the gating system feeder, characterized in that, in order to simplify the construction, the channel surface for the feeder in the insert from the ejector side of the gate is made along a radius whose center is on the line of intersection of the internal surface of the channel for the feeder, located opposite the gate ejector, with a broken insert surface, located on the side of the gate ejector. 2. The mold according to claim 1, wherein the radius value is determined by the ratio , where r is the channel radius for feeder; h is the feeder channel thickness; b is the thickness of the insert. Sources of information taken into account in the examination; 1. USSR author's certificate number 583870, cl. B 22 D 17/22, 1977. 2. USSR author's certificate number 659280, cl. B 22 D 17/22, 1979. 8 16 17 FIG. f (- / noSepHi / mo Fig.Z 6-6 Fy