|
(11) | EP 1 609 571 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
||||||||||||||||
|
|||||||||||||||||
| (54) | Ceramic liners for the pressing of tiles |
| (57) The ceramic liners for the pressing of tiles are composed of two elements: a metallic
empty case that has two extensions in the upper and lower side, and a ceramic fired
strip, which is inserted by pressure inside the metallic case, and can be manufactured
by pressing, extruding and casting. The ceramic liners for the pressing of tiles can
be fixed directly to the frame by horizontal screws that hold from behind each one
of the metallic cases, or indirectly by the same horizontal screws to a double frame,
which fits to the window of the frame by vertical screws in a step done for this purpose. |
OBJECT OF THE INNOVATION
[0001] The objects of this innovation are the ceramic liners for the pressing of tiles, as a part of the frames used in the presses for the manufacturing of tiles.
[0002] The main issues of the invention are the two components of the liners, a metallic piece and another piece made of ceramic materials.
[0003] So the invention belongs to the scope of the liners used for the pressing of tiles, which shapes the edge of the floor and wall tiles.
BACKGROUNDS
[0004] The liners are spare parts of the complete mould used in presses for ceramic industry. The upper surface and the back surface of the green tile are shaped by an upper and lower punch. The liners shape the edge of the green tile.
[0005] The liners are fixed in each cavity of the metallic frame. By the time of pressing, the lower, the upper punch and the liners meet in each window, pressing the surface, the back and the edge of the green tile in each stroke of the press.
[0006] Nowadays the liners used in the ceramic industry are metallic pieces fixed on each window of the frame closing its sides. The fixation of the liners is done by horizontal screws, through the frame or the liners; by vertical screws in the step of the frame through the liners; by magnetic means, etc. To make these liners is used steel with various metallic compositions, often with an additional thermic treatment. Despite of these kinds of treatments the liners suffer daily erosion, especially along the slot, because of the constant abrasion of the ceramic powder.
[0007] To avoid the abrasion recently it has been introduced a metallic liner with a coating of powder made of ceramic oxides or metallic carbides, through techniques of thermic projection of plasma or HVOF (High Velocity Oxygen Fuel). Nevertheless, this coating process, with very high temperatures using a high velocity flow of gas, requires the use of specialised and expensive machinery. So the production of the liners becomes more expensive and slower.
[0008] In anyway, all the liners described, both, the four liners fixed in a square frame and the one-piece liner fixed in the step of the frame, are made only in one element.
[0009] It has been developed a liner that is composed of two elements to overcome all the disadvantages described before. The first element is a metallic case and the second one is a fired piece of ceramic material that fits inside the metallic case.
[0010] The hardness of the ceramic material used to make the second element can assure a higher resistance to the abrasion. Moreover the new liners do not need a later thermic treatment like the thermical shock in the kiln, the thermic projection of plasma or the HVOF described before. Finally the special configuration of the liners allows to change only the ceramic element crushed keeping the metallic case for ages; this means an important reduction of costs in repairs and substitutions of spare parts.
DESCRIPTION OF THE INNOVATION
[0011] The proposed innovation of ceramic liners for the pressing of tiles, is characterised because of the two different elements included in each liner:
- One metallic element with the shape of an empty case that anchor the ceramic element by means of two extensions in both of the external sides.
- Another element made of ceramic material and fired that is pushed in one side of the metallic case fitting inside it with a perfect adjust of a few tenths of millimetre of tolerance. So the ceramic element will not move during the pressing.
[0012] The ceramic component of the liner is composed by a combination of ceramic materials and several metals (oxides and ceramic silicates, wolfram, chrome, iron, nickel, cobalt, titanium, aluminium, etc.). All of these components in powder became, after fired, a right strip, with the traditional shape of the four-piece liners. Whatever of the production systems suitable for the production of the ceramic pieces can be applied to the manufacturing of this fired ceramic element:
- Pressing the powder by a mould equipped with punches and liners.
- Extruding the powder mixed with water, which is pushed out through a mouthpiece that gives to the material the desired shape.
- Casting the powder mixed with water inside a porous mould that gives to the material the desired shape.
[0013] The fixation of the set of metallic case and ceramic strip can be done by two different means:
- Conventional way, in which each liner is fixed to the frame by horizontal screws. The screws anchor the metallic case from behind, through the frame.
- By a double frame. The metallic case is fixed from behind with horizontal screws to a double frame, which is adjusted to the window of the frame by vertical screws, in the step made for this purpose. Thus, it is possible to change only the ceramic element, or the set of case and ceramic strip, disassembling only the double frame.
DESCRIPTION OF THE DRAWINGS
[0014] To complete the description, and to reach a better understanding of the invention features, it is enclosed a set of drawings, in which pictures it are represented in detail the most important features of the invention, in a descriptive and non-restrictive way.
[0015] The drawing number 1 represents the frame (1), in which windows are fixed the ceramic liners for the pressing of tiles (2). It is also represented in detail the metallic case (3) and the ceramic strip (4); as well as an increased section of both elements.
[0016] The drawing number 2 represents the frame (1), in which windows are fixed a double frame (6), and one ceramic liner; as well as a detailed and increased section of the metallic case (4) and the ceramic element (2).
PREFERRED WAY TO CARRY OUT THE INVENTION
[0017] Paying attention to the mentioned drawings, we are going to describe the preferred way to carry out the invention.
[0018] The ceramic liners for the pressing of tiles (2) are adjusted to the window of the frame (1), closing the sides of the cavity. In this cavity the press shapes the pieces of floor or wall tile, through the pressure transmitted by the upper and lower punches, which are precisely adjusted to the window of the frame (1). So the liners (2) shape the edge of the tile in a little cutting surface, which suffer the constant erosion of the ceramic powder.
[0019] To improve the resistance of the liner (2) against the abrasion of the ceramic material, we have created a liner with two elements: a metallic empty case (3), and a ceramic strip (4).
[0020] There are two ways to hold the liners (2) to the frame (1), described in the drawings 1 and 2.
[0021] In the drawing 1 it is represented a liner (2) fixed to the frame (1) by horizontal screws (5) that hold each metallic case (3) from behind, from the inside of the frame. In the meanwhile, the ceramic strip (4) fits by pressure inside the metallic case (3), introduced by one of its sides.
[0022] In the drawing 2 it is represented a set of liner (2) and metallic case (3), fixed from behind to a double frame (6) through horizontal screws. The double frame (6) is anchored to the window of the frame (1) by vertical screws (7), to a step done with this purpose. The ceramic element (4) is introduced again by one side of the metallic case (3), in which fits by pressure.
[0023] We do not consider necessary to go further in the description of the invention in order to explain the scope and the advantages of the invention to an expert in this matter.
1. Ceramic liners for the pressing of tiles, characterised by each liner (2) composed of two different elements, a metallic empty case (3), which
has two extensions in its upper and lower side, and a ceramic fired strip (4), which
is inserted by pressure in the metallic case (3).
2. Ceramic liners for the pressing of tiles, accordingly with claim 1, characterised by the ceramic strip (4) manufactured by pressing.
3. Ceramic liners for the pressing of tiles, accordingly with claim 1, characterised by the ceramic strip (4) manufactured by extruding.
4. Ceramic liners for the pressing of tiles, accordingly with claim 1, characterised by the ceramic strip (4) manufactured by casting.
5. Ceramic liners for the pressing of tiles, accordingly with previous claims, characterised by liners (2) anchored to the frame (1) by horizontal screws (5), that hold form behind,
from inside the frame (1) each one of the metallic cases (3).
6. Ceramic liners for the pressing of tiles, accordingly with claim 1 to 4, characterised by metallic cases (3) fixed from behind by screws (5) to a double frame (6), which fits
to the window of the frame (1) by vertical screws (7) to a step done with this purpose.
Amended claims in accordance with Rule 86(2) EPC.
1. Ceramic liners for the pressing of tiles, consisting of two different elements, a
metallic empty casing (3) and a ceramic fired strip (4) slided into the metallic empty
casing (3) that has two grips in its upper and lower side to hold the ceramic fired
strip (4).