EP1508415A2

EP1508415A2 - Mold for ceramic tiles with strip extractor

Info

Publication number: EP1508415A2
Application number: EP04017862A
Authority: EP
Inventors: Michele Gatti; Marco Severi
Original assignee: GAPE DUE Srl
Current assignee: GAPE DUE Srl
Priority date: 2003-08-22
Filing date: 2004-07-28
Publication date: 2005-02-23
Also published as: ITMO20030237A1; EP1508415A3

Abstract

A supporting framework (7) for supporting strips (6) of a mold for ceramic tiles provided with a die (3) can be extracted, in inactive conditions, by means of a lateral (or longitudinal) extractor of the drawer-like type, which is inserted in a seat (8, 9) formed in the die and contains, in addition to the supporting framework (7), at the inlet of the seat, a transverse bar (10) for longitudinal and vertical locking, to be removed for drawer-like extraction; the supporting framework is used in ceramic factories to avoid disassembling the die (3) when it is necessary to replace worn strips (6) or to obtain different thicknesses of tiles of the same format or variations of the profile of the edges of the tile.

Description

The present invention relates to a mold for ceramic tiles with strip extractor, i.e., to a mold in which the strips, i.e. the plates that are notoriously provided as wear protection and line the walls of the cavity of the die in which the punch and/or plug for forming the tile is coupled so that it can slide vertically, can be extracted and replaced by means of an extractor without having to disassemble the mold from the press.
The background art does not comprise extractors, i.e., devices that allow to extract the strips without having to remove the die from the press, since it is not possible to use, as a work area for disassembly on site, the confined space provided between the two mold parts, therefore without having to interrupt production for a considerable time in order to disassemble the mold part and without having to use corresponding means and labor.
The need to extract the strips occurs not only when the degree of wear of their active surface requires their replacement, but also when it is necessary to shift to the production of tiles having slightly different format and/or thickness and/or edge profile or when the strips of the die are monolithic, i.e., form a frame with an inclined face; this occurs because the strips are not designed merely as wear-preventing guides for the sliding of the punch or plug therein, but are also designed to complete the profile of the edge of the tile, albeit within certain dimensional limitations, advantageously allowing to use a same mold to produce different tiles by changing only the strips.
Accordingly, the need for strip replacement can occur frequently.
This background art is susceptible of further improvements, as regards the possibility to avoid disassembling the die from the press when it is necessary to replace the strips, as occurs often due to the above described reasons.
Accordingly, the aim of the present invention is to solve the problem of finding a device that is suitable to extract the strips without disassembling the corresponding mold part or die of the press, therefore saving time, means and labor, both for molds with a single impression or die and for molds with multiple dies, taking into account the need to prevent the adoption of said device from entailing separations that compromise the stability of the mold during tile forming operations, particularly on presses with power levels on the order of thousands of tons.
The above aim is achieved by using, in the die, a strip supporting framework, which is locked therein during use, can be extracted therefrom and reinserted therein with a drawer-like motion, constitutes the extractor, and comprises at least one strip of the set of strips, usually a group of four strips fixed independently to said framework for example by means of screws, or at least one set of said strips formed monolithically, so as to form a frame that is likewise fixed to said supporting framework.
The advantages obtained by the present invention are: quick separation of the strips from the corresponding die still mounted on the press, with the possibility to immediately insert in the same die a similar drawer-like supporting framework provided with strips as a replacement of, or as an alternative to, the preceding strips; short duration of the separation operation, to the extent allowed by the need to firmly lock the supporting framework to the die in view of the value of the forces, on the order of thousands of tons; minimal downtime of the press; mold stability.
Some embodiments of the invention are shown merely by way of example in the accompanying drawings, wherein:
Figure 1 is a partial sectional view, taken along a vertical transverse plane, of a mold, for example of the type with loose powder transfer, which is mounted on the press and is provided with two impressions;
Figure 2 is a bottom view of the upper mold part, illustrating the device according to the invention and, in a lower region and in dashed lines, the transverse bar for vertical and horizontal locking of the supporting framework, with means for the horizontal locking thereof extracted from their seats;
Figure 3 is a partial and discontinuous enlarged-scale view of the upper part of the mold of Figure 1, illustrating the strip supporting frame, which can be extracted longitudinally in a drawer-like fashion from the die, i.e., laterally with respect to the mold;
Figure 4, in its right portion, is a partial sectional view of the upper mold part, taken along a longitudinal vertical plane, therefore at 90° with respect to the view of Figure 1, and its left portion illustrates in dashed lines and in an exploded view, from the right, the supporting framework that encloses the set of strips of an impression, the front edge of the die, and a plug for horizontal locking in the initial position;
Figure 5 is a partial enlarged-scale view of a part of Figure 4, illustrating the longitudinal extraction and locking device;
Figure 6 is a bottom view of the upper part of the mold in the case of four impressions, with two independently extractable strip supporting frameworks;
Figure 7 is a view, similar to Figure 6, in the case of a mold with three impressions, with two mutually independent supporting frameworks.
With reference to the figures, the reference numerals 1 and 2 respectively designate the upper and lower parts of the mold (i.e., the upper mold part and the lower mold part), for example of the type in which the powder released from the feed carriage into an impression 4 of the lower part 2 of the mold is transferred to a die 3, which is arranged above; the reference numeral 5 designates a punch that generates the exposed face of the tile; the reference numeral 6 designates strips, fixed by way of means that are not indicated, such as screws, to a supporting framework 7, which in turn is fixed to the die 3 for example by means of screws 6a. The supporting frame, for its drawer-like extraction after removing the screws, is coupled so that it can slide longitudinally on a bottom 8 and on sides 9 of a corresponding seat formed in the lower face of the die 3. The supporting framework is contained at the front by a transverse bar 10 for containment and locking, which is coupled so that it can be extracted in the seat 8 and 9 and is fixed therein for example also by means of vertical screws 11, which are embedded in corresponding recessed seats 12 and by means of longitudinal plugs 13, which are inserted in seats 14 and push simultaneously on the transverse bar 10 and on the overlying die 3 so as to straddle their parting plane, with the supporting framework 7 fixed, for example by means of screws 6a, also to the transverse bar 10; the reference numeral 15 designates two lateral slots of the supporting framework 7 for the longitudinal drawer-like sliding of said framework after removing the transverse bar 10, the screws 11 and the means, such as for example the screws 6a, for fixing said framework to the die 3. The reference numeral 16 designates lateral elements for slidingly supporting the framework 7 during extraction from, and insertion into, the die 3; the reference numeral 17 designates a pressure distribution unit, which is shaped like a cup with a perforated bottom and is inserted in a seat 18 formed in the transverse bar 10 and fastened by means of a screw 19, which constitutes the longitudinal fixing plug 13, which presses simultaneously against the surface of the die 3 (in the lower part) and of the transverse bar 10 (in the upper part) so as to straddle their asymmetric parting plane in order to distribute the longitudinal locking pressure.
In the practical embodiment, the materials, the dimensions, the constructive details, the fixing means 6a, 11, 13 and the sliding guiding means 15 and 16 may be different from the ones described herein but technically equivalent thereto without thereby abandoning the scope of the appended claims.
Moreover, although it is more convenient in the case in which the die 3 is arranged upward, the device according to the invention can also be applied in the case of a die arranged downward and for any possible type of tile mold in addition to the one described.
Finally, depending on the shape of the perimeter of the tile, the set of strips may comprise a different number of independent strips.
Moreover, the extractor can be applied to a single mold part, in particular an upper one but also a lower one.
The disclosures in Italian Patent Application No. M02003A000237 from which this application claims priority are incorporated herein by reference.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

A mold for ceramic tiles with strip extractor, comprising a set of independent or monolithic strips (6), characterized in that at least one of said strips is fixed to a supporting framework (7) that can be extracted in a drawer-like fashion from the die (3) after removing a locking system.
The mold according to claim 1, characterized in that said supporting framework (7), fixed in any manner to the die (3) during operation of the press and adapted to slide in a seat (8, 9) of said die, is provided laterally, for each side, with at least one slot (15), in which at least one lateral element (16) for supporting said supporting framework (7) is engaged, said supporting element protruding from the die (3) and entering said slot.
The mold according to one of claims 1 and 2, characterized in that at least one element for locking the working position of said supporting framework (7) to said die in at least one direction is inserted in the front longitudinal part of the seat (8, 9) of said die (3).
The mold according to claim 3, characterized in that said at least one locking element is constituted by a transverse bar (10), which is adapted to lock at least one longitudinal locking element in a longitudinal direction by longitudinal pressure against said supporting framework (7) and against said die (3).
The mold according to claim 3, characterized in that said at least one locking element is constituted by a transverse bar (10) provided with at least one vertical locking element.
The mold according to claim 4, characterized in that said at least one longitudinal locking element is constituted by a block with a cup-shaped pressure distribution element (17), which is inserted in a seat (13) formed in said transverse bar (10) and in said die (3), said pressure distribution element (17) pressing longitudinally against said transverse bar (10) and said die (3).
The mold according to claim 5, characterized in that said vertical locking is achieved by way of means (11) inserted in recessed seats (12) of said longitudinal bar (10).
The mold according to claim 1, characterized in that at least one of said supporting frameworks (7) is inserted in each die (3).