RU2545353C1 - Production of mould for vacuum forming - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to production of moulds for vacuum forming of articles from polymer mass of preset shape of face surface and quality. In compliance with this process, article model is made. Model face surface is prepared, separation ply is applied on said face surface, framework in installed to be filled with epoxy resin. Resin solidified, epoxy frame is detached from the model. Separation ply represents a thermoplastic resilient sheet with preset surface texture and quality to cover by vacuum forming the model face surface.

EFFECT: production of face surface of preset surface texture and quality, better manufacturability, lower labour input, enhanced application.

Description

The invention relates to methods for manufacturing molds for molding by vacuum method from the polymer mass of products with the front surface of a given texture and quality.

From patent RU 2219054 C1, IPC 7 B29C 33/40, publ. December 20, 2003, there is a known method of manufacturing a mold for producing products by contact molding, which includes performing the model, preparing the front surface of the model, applying to the model a face layer of a curable polymer material based on organosilicon rubber, partial curing, laying an intermediate layer of reinforcing fabric impregnated with the aforementioned polymer material, curing, laying a layer of fiberglass material in the presence of a polyester resin, final curing and removal of the mold from the model.

The disadvantage of this method is the high complexity, due to the need for careful preparation of the front surface of the model.

The prior art is the use of wooden and synthetic blocks for the manufacture of models.

The complexity of working with wooden blocks is due to the heterogeneous structure of the tree, requiring painstaking refinement of the front surface.

Synthetic resin blocks have a homogeneous structure, which makes it easier to obtain a smooth front surface, however, such blocks are much more expensive and when they are machined, working conditions harmful to the health of the worker are created.

From patent RU 2048237 C1, IPC B22C 9/02, publ. November 20, 1995, there is a known method of manufacturing a model for molding products using the vacuum method, in which, after making a model from a wooden block, it is covered with fabric.

The advantages of the above method of manufacturing a model for molding products by the vacuum method is the reduced complexity of obtaining the front surface of the texture that simulates fabric.

The disadvantage of the above method is the limited applicability due to the inability to obtain the front surface of the model with a given texture and quality. Using this method, in particular, it is impossible to obtain a smooth surface or a surface imitating the texture of the skin ("shagreen leather") or carbon fiber ("carbon").

For the closest analogue of the claimed invention, a method of manufacturing a mold for molding articles from polymer materials by a vacuum method is adopted, see patent RU 2327564 C2, IPC B29C 51/36, 33/38, publ. 06/27/2008, in which the model is executed, the front surface of the model is prepared, the separation layer is applied to the model, the formwork is installed, the first working layer of fiberglass impregnated with heat-resistant epoxy resin is applied, and then several layers of fiberglass impregnated with ordinary epoxy resin, and after curing the resin, the epoxy form is separated from the model and, in the form obtained, holes are drilled over the entire surface area intended for vacuum molding.

The disadvantages of the closest analogue are low manufacturability, high complexity, which are due to the need for careful manual preparation of the front surface of the model, and limited applicability due to the impossibility of obtaining the surface of a given texture.

The technical result to which the invention is directed is to create a method for manufacturing a mold for molding products from polymer mass by the vacuum method, which makes it possible to obtain a front surface with a given texture and quality, characterized by increased manufacturability, reduced manufacturing complexity and expanded applicability.

The specified technical result is achieved in a method of manufacturing a mold for vacuum forming products from thermoplastic materials, in which:

- make a product model;

- prepare the front surface of the model;

- apply a separation layer to the front surface of the model;

- establish the formwork;

- fill the formwork with epoxy resin;

- after curing the resin, the epoxy form is separated from the model.

The indicated technical result is achieved in that a thermoplastic elastic sheet material with specified texture and surface quality is used as a separation layer, which is used to tighten the face of the model by vacuum molding.

For the practical implementation of the invention perform the following sequence of actions.

Cut the product model from wooden or synthetic blocks with a hand tool or on a machine. The surface of the product is made with a minus allowance equal to the thickness of the then applied layer of thermoplastic material. Additional processing of the front surface is not performed.

Using the vacuum molding method, the model is covered with a thin layer of thermoplastic elastic sheet material with the specified texture and surface quality.

As a result, the model acquires a surface with the specified texture and quality, which are determined by the texture and surface quality of the thermoplastic elastic sheet material.

In the proposed method, it is not necessary to apply an additional separation layer to the model covered with thermoplastic elastic sheet material, since its functions are performed by thermoplastic elastic sheet material. As a thermoplastic elastic sheet material, material from the group of thermoplastic elastomers can be used, for example:

- ULSO-PRENE TS (heat-resistant) manufactured by UltraSoft Plastic LLC (Moscow);

- thermoplastic elastomers butadiene-styrene DST-R, DST-RM, DST-25, DST-30, DST-50 manufactured by OJSC "Voronezhsintezkauchuk";

- thermoplastic elastomers KOPEL®.

Install the formwork. Fill the formwork with epoxy.

After curing the epoxy, the model is removed from the release elastic layer, and then the release release layer is removed from the cured epoxy form.

The products are molded into the resulting mold in the usual manner known per se.

Using the same equipment (vacuum molding machine) as for the subsequent manufacture of products for preparing the front surface, significantly simplifies, facilitates, and speeds up the manufacturing process of both the model and the mold as a whole.

The practice of using the claimed invention has confirmed its industrial applicability and the compliance of the obtained technical result with the declared one.

Claims (1)

A method of manufacturing a mold for vacuum molding of products from thermoplastic materials, in which a product model is made, the front surface of the model is prepared, a separation layer is applied to the front surface of the model, the formwork is installed, the formwork is filled with epoxy resin, and after curing the resin, the epoxy form is separated, characterized in that that as a separation layer using a thermoplastic elastic sheet material with a given texture and surface quality, which is tightened met vacuum molding the front surface of the model.