RU2072304C1 - Mold for fabricating objects under high pressure - Google Patents

Abstract

FIELD: polymer molding. SUBSTANCE: invention relates to working polymer materials by molding under high pressure and may find use when manufacturing high-precision parts. Purpose of invention is to improve quality of molded objects owing to consolidation of polymer material under high pressure from the side of mobile half-mold when transferring clamping force directly into mold cavity. To achieve it, mold is provided with mobile molding members with flanges to be mounted on the mobile half-mold, and intermediate plate is made in the form of parallel plates successively installed in direction of mobile half- mold. The latter is molding half-mold with spot running channels communicated with central running channel, and also displacing, centering, and axillary half-mold. Elastic member is installed between mobile half-mold and intermediate plate connected with mobile half-mold through molding members. EFFECT: improved quality of molding. 1 dwg

Description

 The invention relates to the processing of polymeric materials by injection molding and can be used in the manufacture of high-precision products.

 The purpose of the invention is to improve the quality of injection molded products by compaction of the polymeric material at high pressure while transmitting the closing force directly to the forming cavity from the side of the movable half-mold.

 The invention is illustrated in the drawing.

 The injection mold contains a fixed half mold 1 with a central gate channel 2, a composite intermediate plate 3 made in the form of a set of parallel plates sequentially installed in the direction of the movable half mold: forming 4 with point gate channels 5 in communication with the central gate channel, pushing 6, centering 7 , auxiliary 8, flanges 9 with design marks 10, attached to the movable half-mold 11, and elastic elements 12. Design marks can be mounted on one flange. Belleville springs GOST 3057-79 can be used as elastic elements.

 Depending on the size and number of springs, the pressure in the mold cavity can be adjusted. Composite intermediate plate is made in the form of a set of plates due to the fact that it performs several functions. In the design, with spot gating channels, the plate is the design of the product. This design of the gate system is explained by the requirements for the product. The pushing plate makes a removal of a product. The presence of the centering plate is explained by the manufacturing process of the plates. The auxiliary plate interferes with the movement of the guide sleeves for the forming marks under the action of the melt pressure.

 Injection mold works as follows.

 At the first stage, the movable 11 and the stationary 1 half-molds are closed under a small force, while the metered material is injected from the material cylinder of the injection machine through the central 2 and 5 point gating channels into the forming cavities under a normal casting pressure of up to 200 MPa. After the injection has occurred, the required closing force of the half-molds is automatically set (the machine switches to injection molding mode). Then there is a movement of the flanges 9 with the design marks 10, mounted on the movable half-mold 11 until it touches the auxiliary plate 8, accompanied by compression of the elastic elements 12.

 At the same time, the forming marks 10 are moved relative to the intermediate plate 3, made in the form of a set of parallel plates, sequentially installed in the direction of the movable half-mold: making 4 with point gating channels 5, connected with the central gating channel, pushing 6, centering 7, auxiliary 8, into the forming cavity filled with the melt, creating increased pressure in the mold, thereby sealing the product. The reverse flow of the melt through the sprue channels 5 does not occur, since by the time the registration marks move into the forming cavity, the melt freezes in them. The use of movable decorating signs, mounted in several or in a common flange 9, moving in an intermediate plate made in the form of a set of parallel plates, sequentially installed in the direction of the movable half-mold: decorating with point gating channels communicating with the central gating channel, pushing and auxiliary, allows to seal the product at high pressure from the side of the moving half-mold, transferring the closing force of the injection molding machine, excluding its loss in sealing Av in the sprue portion and the punching melt point through sprues.

Claims (1)

 An injection mold for producing high-pressure products, comprising a movable half-mold, intermediate and fixed plates, an elastic element and a gating bush with a central gating channel ending with a drive, characterized in that, in order to improve the quality of the molded products by compacting the polymer material at high pressure with the sides of the movable half-mold when transferring the clamping force directly to the forming cavity, it is equipped with movable forming marks with flanges for their fastening, mounted on the movable half-mold, while the elastic element is located between the movable half-mold and the intermediate plate connected to it by design marks made in the form of parallel plates sequentially installed in the direction of the movable half-mold: decorating with point gating channels communicating with the central gating channel, pushing, centering and auxiliary.