EP1132201A1

EP1132201A1 - Decorating machine for ceramic elements

Info

Publication number: EP1132201A1
Application number: EP01103486A
Authority: EP
Inventors: Francesco Schinco
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-02-15
Filing date: 2001-02-15
Publication date: 2001-09-12
Also published as: IT1315593B1; ITMO20000021A1

Abstract

A decorating machine (1) comprising shaft means (4) and sleeve means (9) rotatably supporting decorating cylinder means (12, 27), decorating means (23, 31) suitable for interacting with said decorating cylinder means (12, 27), driving means (6) for rotating said shaft means (4) and said sleeve means (9) at the same angular speed, further comprises assembly means (10, 26, 11; 30) allowing first decorating cylinder means (12) and first decorating means (23) or second decorating cylinder means (27) and second decorating means (31) to be assembled on said shaft means (4) and on said sleeve means (9).

Description

The invention relates to a decorating machine for ceramic elements with interchangeable printing devices, in particular a rotary printing machine for making printed decorations on ceramic elements, which can be easily converted in order to use different printing methods.
In prior art, different types of decorating machines are known in order to make decorations on ceramic products, using different printing methods, for example damp silk-screen machines, wherein the decorations are obtained by using a cylindrical silk-screen, pad printing machines, wherein a printing cylinder is used on which the decorating patterns to be reproduced on the surface to be decorated are impressed in relief, and flexographic machines wherein a printing cylinder is used, the decorating patterns to be reproduced on the surface to be decorated being engraved on the surface of said printing cylinder.
All these machines are not generally interchangeable therebetween: in particular a silk-screen machine cannot be used in order to make a decoration with the pad printing method, or a pad printing machine cannot be used in order to make decorations with the silk-screen method.
For this reason, the users of decorating machines have to equip themselves with more pad printing or flexographic and silk-screen machines, if they need to make decorations with methods of different types, which implies remarkable investments and an improper utilisation of the machines.
A purpose of the present invention is to provide a decorating machine that is multifunctional, i.e. that can be used to make decorations with different decorating methods.
According to the present invention, a decorating machine is provided, comprising shaft means and sleeve means, rotatably supporting decorating cylinder means, decorating means suitable for interacting with said decorating cylinder means, driving means for rotating said shaft means and said sleeve means at the same angular speed, characterized in that, it further comprises assembly means allowing first decorating cylinder means and first decorating means or second decorating cylinder means and second decorating means to be assembled on said shaft means and on said sleeve means.
In a preferred embodiment, said first decorating cylinder means comprises silk-screen decorating cylinder means and said first decorating means comprises silk-screen decorating means.
In another preferred embodiment, said second decorating cylinder means comprises flexographic decorating cylinder means and said second decorating means comprises flexographic decorating means.
Said assembly means allows the machine according to the invention to be used both in order to make decorations with silk-screen method and to make decorations with flexographic method, changing a minimum number of parts and using always the same machine framework and the same driving system. This remarkably reduces the investment costs and provides a machine having great use flexibility and which can be intensively used, minimum idle times being required for converting the machine from one printing method to another.
The invention will be described more in detail below, with reference to the enclosed drawings, which show some not restrictive, implementation examples thereof, wherein:
Figure 1 is a front view of a decorating machine according to the invention, in the working condition wherein a traditional silk-screen is used;
Figure 2 is a section along the plane II-II of the machine of Figure 1;
Figure 3 is an enlarged and broken detail of the section of Figure 2;
Figure 4 is a side view of tensioning means and paddle means used in the working condition wherein a traditional silk-screen is used;
Figure 5 is a section V-V of the view of Figure 4;
Figure 6 is a front view of a decorating machine according to the invention, in the working condition wherein a flexographic roller is used;
Figure 7 is a section along the plane VII-VII of the machine of Figure 6;
Figure 8 is an enlarged and broken detail of section of Figure 7;
Figure 9 is a side view of holding means and of doctor blade means used in the working condition wherein a flexographic roller is used;
Figure 10 is a section X-X of the view of Figure 9.
With reference to Figures 1, 2 and 3, a decorating machine 1 according to the invention is shown, equipped so as to decorate ceramic elements by using a cylindrical silk-screen 12 of a known type. The decorating machine 1 comprises a frame 2 to which a hollow cylindrical element 3 is fixed, horizontally extending above a handling system 5 of ceramic elements. The hollow cylindrical element 3 is fixed to a block 40 slidable in a vertical direction on guide means 41, so that its distance from the handling system 5 of ceramic elements can be adjusted. A rotatable shaft 4 is provided inside the hollow cylindrical element 3. Driving means 6, fixed to the block 40, drives both the shaft 4, through a first gear set 7, and a sleeve 9, through a second gear set 8. The sleeve 9 is arranged outside the hollow cylindrical element 3 and can be rotatably coupled thereto; a plate 10 having a circular shape is fixed to the sleeve 9, and in the plate 10 a hole is made, with the same centre as plate 10, through which the hollow cylindrical element 3 can pass. If components of the gear sets 8 and 9 are properly sized, the shaft 4 and the plate 10 will rotate at the same angular speed. As the ends 13 of the above-mentioned cylindrical silk-screen 12 are fixed to the shaft 4 and to the plate 10, as it will be described below, torsion of the silk cloth 14 of the silk-screen 12 is prevented, printing operations being thus optimised.
Tensioning means 11 of the silk cloth 14 of the silk-screen 12 consists of a circular crown 15, to which one of the ends 13 of the silk-screen 12 can be fixed, said circular crown 15 being connected to a hub 16 by spokes 16a; a rod 17 passes through the hub 16, said rod 17 being rotatably coupled with the hub 16, and having a threaded end 18 suitable for engaging a respective nut screw element 19 obtained on the end 4a of the shaft 4; the other end of the rod 17 is connected to a handwheel 20 allowing the threaded end 18 to be guided so as to engage the nut screw element 19, and further allowing the translation of the threaded element 18 to be axially adjusted with respect to the nut screw element 19.
The silk-screen 12 can be assembled as explained here below. Two metallic flanges 13a are arranged at the ends 13 of the silk-screen 12, said flanges 13a being respectively fixed to the plate 10 and to the circular crown 15 through blocking means 26, each of which consists of two semicircular elements mutually hinged and internally grooved. After fixing the flanges 13a of the silk-screen 12 respectively to the plate 10 and to the circular crown 15, the silk cloth 14 can be stretched. To make this operation, it is necessary to act on the handwheel 20 which controls the threaded end 18 of the rod 17, pulling the circular crown 15, fixed thereto, away from the plate 10, which is kept in its position.
The connection between the shaft 4 and the hub 16 is made through a tube means 21, interposed between them, fixed to the hub 16 by a threaded coupling 22, and having a surface which can be shapingly coupled with the grooved terminal portion 4a of the shaft 4.
With reference to Figures 4 and 5, paddle means 23 is arranged inside the cylindrical silk-screen 12 in order to provide to the glaze transferring from the inner portion of the silk-screen 12 to the surface of the ceramic elements. The paddle means 23 is supported by a tubular element 24, externally arranged with respect to the hollow cylindrical element 3, two actuators 25 being fixed to said tubular element 24, so as to allow the movement of the paddle means 23 along a vertical direction.
With reference to Figures 6 to 10, a decorating machine 1 according to the invention is shown, equipped so as to decorate ceramic elements through a flexographic printing roller 27.
Similarly to the previously described case, the decorating machine 1 comprises a frame 2 to which a hollow cylindrical element 3 is fixed, horizontally extending above a handling system 5 of ceramic elements. The hollow cylindrical element 3 is fixed to a block 40, vertically slidable on guide means 41. A rotatable shaft 4 is provided inside the hollow cylindrical element 3. Driving means 6, fixed to the frame 2, drives both the shaft 4, through a gear set 7, and a sleeve 9, through a second gear set 8. Holding means 30 suitable for holding in a proper working position a flexographic printing roller 27 comprises pressing means 28, a rod 17 rotatably coupled thereto, having a threaded end 18, suitable to engage a corresponding nut screw element 19 obtained at the end 4a of the shaft 4; the other end of the rod 17 is connected to a handwheel 20 which allows, acting on the threaded end 18, the pressing means 28 to be held in its working condition.
The connection between the holding'means 30 and the shaft 4 is obtained by shapingly coupling respective grooves.
In order to equip the machine 1 so as to change from a working condition with a silk-screen 12 to a different working condition with a flexographic printing roller 27 the following actions can be done.
After acting on the handwheel 20 so as to release the tension on the silk cloth 14 of the silk-screen 12, the blocking means 26 is removed and the silk-screen 12 is drawn out. Furthermore, the tubular element 24 is pulled out and consequently the paddle means 23 fixed thereto is removed.
Then the plate 10 is disassembled from the sleeve 9 through the removal of the fixing screws 10a; no other elements have to be inserted for mounting the flexographic printing roller 27 since its metallic ends 27a abut directly against the sleeve 9. The tensioning means 11 is substituted by the holding means 30, since the flexographic printing roller 27 is rigid and does not require any tensioning as the silk-screen 12 does. The above mentioned holding means 30 block the roller 27, by pressing it against the sleeve 9, thus holding the roller 27 in its working position.
Since, usually, the flexographic printing roller 27 has a smaller diameter than the silk-screen 12, the block 40 is translated downwards along a vertical direction, sliding on the guide means 41, until it reaches the proper distance from the handling system 5 of ceramic elements. The support means 29, suitable for supporting doctor blade means 31, are then positioned, by fixing said support means 29 to the frame 2 externally to the flexographic printing roller 27.

Claims

Decorating machine, comprising shaft means (4) and sleeve means (9) rotatably supporting decorating cylinder means (12, 27), decorating means (23, 31) suitable for interacting with said decorating cylinder means (12, 27), driving means (6) for rotating said shaft means (4) and said sleeve means (9) at the same angular speed, characterized in that, it further comprises assembly means (10, 26, 11; 30) allowing first decorating cylinder means (12) and first decorating means (23) or second decorating cylinder means (27) and second decorating means (31) to be assembled on said shaft means (4) and on said sleeve means (9).
Decorating machine according to claim 1, wherein said shaft means (4) and said sleeve means (9) are rotatably coupled with a hollow cylindrical element (3) horizontally extending from the frame (2) of said decorating machine (1).
Decorating machine according to claim 2, wherein said hollow cylindrical element (3) is fixed to a block (40) slidable along a vertical direction on guide means (41).
Decorating machine according to any of preceding claims, wherein said assembly means comprises plate means (10) to which one end (13) of said first decorating cylinder means (12) is fixed and tensioning means (11) of said first decorating cylinder means (12).
Decorating machine according, to claim 4, wherein said plate means (10) is fixed to said sleeve means (9).
Decorating machine according, to claim 4, wherein said tensioning means (11) comprises a circular crown (15) to which one end (13) of said first decorating cylinder means (12) is fixed.
Decorating machine according to claim 6, wherein said circular crown (15) is connected to a hub (16) through spokes (16a).
Decorating machine according to claim 7, wherein a rod (17) passing through said hub (16) is rotatably coupled to said hub (16), said rod (17) having a threaded end (18) suitable for engaging a corresponding nut screw element (19) obtained at one end of said shaft means (4).
Decorating machine according to any of preceding claims, wherein said shaft means (4) is connected to said hub (16) through tube means (21) interposed therebetween.
Machine according to claim 9, wherein said shaft means (4) is coupled with said tube means (21) through anti-rotation means (4a).
Decorating machine according to any of preceding claims, wherein said first decorating means comprises paddle means (23) supported by a tubular element (24) arranged externally to said hollow cylindrical element (3).
Decorating machine according to claim 11, wherein at least one actuator (25) is fixed to said tubular element (24), said at least one actuator (25) being suitable to actuate in a vertical direction said paddle means (23).
Decorating machine according to any of preceding claims, wherein said first decorating cylinder means comprises silk-screen decorating cylinder means (12).
Decorating machine according to any of preceding claims, wherein said first decorating means comprises flexographic decorating means (23).
Decorating machine according to any of claims 1 to 12, wherein said second decorating cylinder means comprises flexographic decorating cylinder means (27).
Decorating machine according to any of claims 1 to 12, or 15, wherein said second decorating means comprises flexographic decorating means (31).
Decorating machine according to any of claims 1 to 12, or 15, or 16, wherein said assembly means comprises holding means (30) suitable for holding said second decorating cylinder means (27) in the proper working position.
Decorating machine according to claim 17, wherein said holding means (30) comprises pressing means (28) acting on said second decorating cylinder means (27).
Decorating machine according to claim 17, or 18, wherein said holding means (30) and said shaft means (4) are connected through said anti-rotation means (4a).
Decorating machine according to claim 16, wherein said flexographic decorating means comprises doctor blade means (31).