SU1705107A2 - Mould for making polymer articles - Google Patents

Abstract

The invention relates to the processing of injection molded plastics and can be used in the manufacture of molds with tunnel sprues. The purpose of the invention is to improve the reliability of the operation of the mold in the aitomatmatic mode due to the guaranteed reset of the gating system. In the shank and the ejection plate, holes are made in which an additional spring-loaded ejector is placed coaxially pulling out the gate with the rim and installed with a gap relative to the latter. 2 h. apt. 3 il.

Description

The invention relates to the processing of injection molded plastics and can be used in the manufacture of injection molds with tunnel sprues, or through the improvement of the basic AOT device. St. No. 1431947.

The purpose of the invention is to increase the reliability of the operation of the mold in automatic mode due to the guaranteed reset of the gating system.

FIG. 1 shows the casting mold before the start of the run; in fig. 2 - the same, after feeding the products and resetting the products before the gating system is reset: in FIG. 3 shows the arrangement of transverse grooves in the ejector and the gating system prior to discharge.

The casting mold consists of a fixed plate 1 and a movable part, including the decorating plate 2 with slots 3, razorite gating channels 4, undercut 5, supporting plate b, ejectors 7, pressures 8 with transverse grooves 9, tunnel channels 10 and keys 11, ejector central sprue 12 with flanging 13 and shank 14. an ejector block with plates 15 and 16, an additional ejector 17 with a spring 18, a mounting plate 19, a shank 20 with a return spring 21.8 slots 3 are shown products 22, in distributing gates Alah 4 - distributing gates 23, in tunnel channels 10 - tunnel sprues 24.

Casting form works as follows.

The polymer is injected into a closed mold and held under pressure. After the end of the exposure, the fastening plate 19 carrying the movable part of the injection mold departs from the fixed plate 1. With its further withdrawal, the shank 20 reaches the stop of the injection molding machine (not shown), which will cause the ejector block with plates 15 to stop and the ejector burned into them. mi 7, 8,

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which extract the products 22 from the slots 3, and the diluting sprues 23 from the sprues canals A.

The sprue runner system 23 is retained in the decoration plate 2 due to undercut 5. At the same time, the sprue runners 24 are detached from the products 22, removed from the tunnel channels 10 and appear on the transverse grooves 9 of the pushers 8 which are kept from turning by the keys 11. The products 22 fall down, and their detachment from the ejector faces 7 and 8 is facilitated by the elastic deformation that occurs when the tunnel sprues 24 are detached. With further moving of the movable part, the end face of the ejector 17 comes into contact with the shank 14 talkivatel sprue 12 and under the influence of buried flush with the plate 15, compressing the spring 18. Thereafter the ejector 17. end to abut against the plate 15, pushes the runner system 23. otstrelivaets which then under the action of the ejector 17 and the spring 18.

After the products 22 and sprues 23 are cast, the casting form closes, and the spring 21 returns the ejector block with plates 15, 16 and ejectors 7, 8 to the initial position, and the spring 18 pushes the end of the ejector 17 out of the plate 15. After injection of the thermoplastic with the melt pressure, the ejector of the central sprue 12 is pressed up to the stop by means of a flap 13 into the supporting plate 6. Then the cycle is repeated.

An additional spring-loaded ejector imparts an axial thrust to the gating system, allowing it to be safely moved beyond the extended ejectors.

Separating the ejector of the central sprue and the additional ejector makes it possible to separate the products in time and eject the gating system and thereby ensure the separation and

raising tunnel gates from tunnel channels.

Increasing the diameter of the ejector stem of the central sprue allows it to simplify its interaction with the ejector block and to create more favorable conditions for the transfer of enhanced crying.

The arrangement of the planes of transverse grooves in pairs symmetrically with respect to the vertical axis of the injection mold leads to the fact that after removing tunnel gates from the tunnel channels, the spacing gates somewhat bend due to the displacement of the tunnel gates relative to the axes of the tunnel channels, which gives the gating system an additional elastic impulse after it is ejected from the undercut.

The arrangement of the planes of the transverse grooves in the form of a herringbone with the base facing the lower side of the injection molding mold facilitates the fall of the sprues, since it combines the action of another elastic impulse with gravity .;

FORUMAWLAH AND ISLANDS

Claims (3)

1. Casting mold for the manufacture of polymer products according to ed. St. 1431947. characterized by that. what. in order to increase the reliability of its operation in automatic mode due to the guaranteed reset of the gating system, holes are made in the shank and the ejection plate. in which there is an additional spring-loaded ejector, coaxial with the ejector of the sprues and installed with a gap relative to the latter. 2. Casting mold according to claim 1. About tl and h and y and so that the diameter of the tail section of the ejector of the central sprue is larger than the diameter of the additional ejector. 3. Casting mold according to claim 1, such that the grooves in the ejector of the sprues are arranged in pairs symmetrically relative to the vertical axis of the casting mold. 1 gpf cr ft / ha / t iOLSOAL 2 23 9 6) 1 / 8.3