SU413046A1 - - Google Patents

Description

one

The invention relates to the field of plastics processing into products and is intended for the manufacture of products, for example, from caprolon, epoxy compounds and other plastics by the method of free casting.

Injection molds are known for making the method of free-pouring from polymeric materials products with holes, comprising a body and an elastic rod fixed at the base of the body, protected by a sheet material.

However, the known forms do not provide the changeover of the rod in the manufacture of products with holes of different diameters.

The purpose of the invention is to create a mold enabling the manufacture of articles with openings of different diameters.

To do this, in the proposed mold, the rod is made in the form of a set of segments pivotally connected by means of a slider equipped with a compression spring, and in order to seal the zone of contact between the rod and the base of the body and ensure uniform distributed pressure, an annular recess is made on the base of the body it is supplied with rigid and elastic rings placed in the undercut.

FIG. 1 shows the proposed form, a longitudinal section; in fig. 2 - section but

A-A in FIG. one; in fig. 3 - node of the zone of contact of the rod with the base of the body.

The described form consists of a body 1 and a pin 2, mounted on a core fixed at the base of the body, made in the form of a set of segments 3 pivotally connected by means of arms 4 with creep 5, provided with compression 6. The width of the segment is chosen so as not to interfere with it

not moving to the center of the form by an amount sufficient to remove the mark from article 1 |.

The rod is fastened on the plug with 2 nuts 7. In the lower part of the rod there is an annular recess 8 in which are placed

a rigid metal ring 9 and an elastic ring 10 sealing the zone of contact between the rod and the base of the body. Ring 9 provides for transmission through ring 10 of uniform distributed axial pressure on

the base of the corns from the segments 3. The inner diameter of the ring 9 is larger than that of the ring 10 so that the ring 9 does not interfere with the radial pressure of the segments on the ring 10. The segments are inserted into the thin foil shell 11 covering the segments between the segments and sealing the envelope ring 10 (fig. 3).

The metal ring 12 serves to set the mark on the specified diameter. To fasten the segments to the specified diameter inside

a splicing ring 13 is inserted to prevent the radial approach of the segments.

To improve the quality of sealing, the bottom of the annular cavity of the mold can be covered with a disk 14 made of a polymeric material.

The depth of the annular undercut 8 must be equal to or greater than the sum of the thicknesses of the rings 9, 10, the disk 14 and the shell AND, in order not to prevent the material from shrinking.

The order of work with the form is as follows.

Putting down the slider 5, the segments 3 are separated from the rings 10 and 12 (first putting the ring 9 on the ring 10), after which the ring 13 is inserted inside the segments. The segments 3 are wrapped with a thin foil sheath 11, bending the bottom edge under the ring 10.

When assembled, the segments are lowered inside the mold, putting the slider 5 on the stud 2, and tightening the nut 7 with the spring 6 until the minimum force is obtained that guarantees reliable sealing of the contact zone of the rod with the base of the mold. Take out the ring 13, pour the polymeric material (caprolon) in the cavity between the rod and the housing 1.

In the process of material shrinkage, the segments 3 will come closer in the radial direction, overcoming the relatively insignificant resistance of the spring 6. At the same time, rings 9 and 10, which ensure tightness at the moment of material hardening, remain at the same place, causing destruction of the casing II at the interface between the rings and the segments.

After the material has cooled down, the mold is disassembled, the core is taken out, since when the slider 5 is raised, the segments 3 freely approach each other in the radial direction until a gap is formed between them and the product. Then, after the material shrinks during cooling and the formation of a gap between the product and the housing, the product is removed from the housing 1.

Then the cycle repeats.

Subject invention

Claims (2)

1. Casting mold for free-pouring from polymer mats rials of products with openings, comprising a housing and an elastic rod fixed at the base of the housing, protected by a sheet material, characterized in that in order to ensure the retooling of the rod in the manufacture of products with different hole diameters, the rod is made in the form of a set of segments pivotally connected by rods with a slide equipped with a spring of compression. 2. A form according to claim 1, characterized in that in order to seal the zone of contact between the rod and the base of the body and provide a uniformly distributed axial pressure to the base of the body, a ring-shaped recess is made on the rod, in which rigid and elastic rings are placed. Fg4. -f (Rig.2: