EP0919346A1

EP0919346A1 - A process for quickly preparing a mould for clay manufactured articles

Info

Publication number: EP0919346A1
Application number: EP97120587A
Authority: EP
Inventors: Giorgio Bertola
Original assignee: FOMB Officine Meccaniche Bongioanni Srl
Current assignee: FOMB Officine Meccaniche Bongioanni Srl
Priority date: 1997-11-25
Filing date: 1997-11-25
Publication date: 1999-06-02

Abstract

A quick preparation of moulds for manufacturing clay articles in which mould (9) a plaster support (11) or resin blocks (15), and said support (11) or said blocks (15) are coated with a wear-resistant material (13) such as a polymeric material reinforced with ceramic steels.

Description

The present invention refers to a process for quickly preparing moulds for manufacturing clay articles, such as tiles and the like.
It is known that the preparation of moulds to be used with presses for manufacturing clay articles is very laborious because of the nature of the material to work on and the consequent strong wear of the moulds.
Such moulds are made of steel, and the steel has to be subjected to a special heat treatment in order to maintain for a long time a surface hard and strong enough for the intended uses.
To overcome these drawbacks, at present a technique has been used in which positives of the clay article to be moulded are built on the upper and lower faces of the moulds, and then a setting resin, such as an epoxy resin or the like, is poured between said positives and through the casting formed in this way one obtains the negative of the article to be mould.
This is a remarkable improvement with respect to the above mentioned conventional technique, nevertheless the main drawback of this technique is the wear of the membrane, of rubber or similar material, that is usually interposed between the mould and the clay.
It is an object of the present invention to overcome the drawback due to the wear of the membrane interposed between the mould and the clay.
The above object of the present invention is achieved through a process as claimed in claim 1.
Further advantageous features of the invention are recited in the dependent claims.
According to a first embodiment of the invention, a plaster support or insert is formed in the mould, and such support is coated with a material having very good properties of wear-resistance, such as a polymeric material filled with ceramic steels.
According to a second embodiment of the invention, resin blocks are formed inside the mould, that are coated with the above mentioned material having very good properties of wear-resistance, and the so coated blocks are fitted in the mould and secured to the mould by proper means.
Preferably, the above mentioned material having very good properties of wear-resistance used in bothe embodiments of the invention, is a two-component compound formed by a polymeric matrix reinforced with ceramic steels.
The invention will now be disclosed with particular reference to the attached exemplary and non limiting drawings, in which:
Fig. 1 is a schematic view illustrating two positives to be fitted in a mould;
Fig. 2 is a schematic view illustrating the coupling of the two positives of Fig. 1, between which a resin will be poured;
Fig. 3 is a schematic view illustrating a half-mould in accordance with a first embodiment of the invention; and
Fig. 4 is a schematic view illustrating a half-mould in accordance with a second embodiment of the invention.
In Figures 1 and 2, numerals 1 and 3 indicate the positives of the desired manufactured articles in accordance with the above mentioned advanced prior technique.
Betwen said positives 1 and 3 a resin 5 is poured that forms, once set, the negative of the article to be manufactured.
This negative 5 is secured to the upper positive 1 by suitable fastening means, such as screws 7 o the like.
Fig. 3 shows first embodiment of the invention. According to such first embodiment, a support 11 of plaster or similar soft material is directly formed in the mould 9, and such support 11 is coated with a material 13 having very good properties of wear-resistance, such as a polymeric material reinforced with ceramic steels.
A second embodiment of the invention is illustrated in Fig. 4.
In accordance with this second embodiment, two resin blocks 15 are formed that are then coated with the above mentioned wear-resistant material 13, the blocks 15 so coated are fitted in the mould 9 and there fastened with proper fastening means 17.
As indicated above, the wear-resistant material 13 used in both embodiments is preferably a two-component product constituted by a polymeric matrix reinforced with ceramic steels.
En example of such a material is known with the trade name BELZONA 1111.

Claims

A process for quickly preparing moulds for manufacturing clay articles, characterized in that it comprises the steps of:

forming a supporto (11, 15) in said mould (1);

coating the active surface of said support (11) with a material (13) having very good properties of wear-resistance.
A process according to claim 1, characterized in that said support (11) is of plaster or other similar soft material, and is directly formed in said mould (9).
A process according to claim 1, characterized in that said support is formed by blocks (15) of resin that are fitted in the mould (9) after being coated with said wear-resistant material (13) and fastened to the mould by fasting means (17).
A process according to the preceding claims, characterized in that said materiale coating the active surface of said support is a polymeric material reinforced with ceramic steels.
A muld for manufacturing clay articles, made through the process according to any of claims 1 to 4.