CN113524398A

CN113524398A - Press with exhaust system

Info

Publication number: CN113524398A
Application number: CN202110399246.0A
Authority: CN
Inventors: 佛朗哥·戈齐; 卡尔米内·圣乔瓦尼; 欧斯塔基奥·塔拉斯科
Original assignee: System Ceramics Co Ltd
Current assignee: System Ceramics Co Ltd; System Ceramics SpA
Priority date: 2020-04-14
Filing date: 2021-04-14
Publication date: 2021-10-22
Also published as: EP3895864A1; IT202000007861A1

Abstract

A press for granular or powdered material, comprising: an upper plate (11) and a lower plate (12) movable towards and away from each other between a loading position, in which both plates are located at a greater distance, and a pressing position, in which both plates are located at a shorter distance; a conveyor belt (13) movable along a path, having at least one movable stretch (14) parallel to the longitudinal direction (X) and arranged between the two plates (11, 12); two side walls (21, 22) arranged parallel to the longitudinal direction (X) so as to laterally define, with the two plates (11, 12), a pressing compartment (V). At least one of the side walls (21) has a plurality of through holes (210) which place the pressing compartment (V) in communication with the outside environment.

Description

Press with exhaust system

Technical Field

The invention relates to a press for granular or powdery material. In particular, the present invention relates to a press for realising ceramic tiles or slabs.

Background

For some time, presses designed by the applicant have been available on the market, which are particularly effective for pressing large ceramic plates up to the 1800 x 3600mm specification.

The press comprises an upper plate and a lower plate which are movable towards each other to press a layer of ceramic material in granular or powder form. The ceramic material is fed into the pressing space comprised between the two panels by means of a conveyor belt which performs a path provided with at least one movable stretch arranged between the two panels. The press also comprises two side walls, arranged parallel to the direction of advance of the conveyor belt, which laterally enclose the pressing space.

The ceramic material is deposited in the form of a layer on a conveyor belt and is brought by the conveyor belt into the press space between the two plate elements. Once the layer of ceramic material has reached a determined position with respect to the two plates, the conveyor belt is stopped and the plates are moved towards each other to press the layer.

The pressing of the layer is essentially a gradual compression of the ceramic material, which reduces the spaces between the granules or particles and, in the case of granules in the form of hollow particles obtained by atomization, crushes the granules themselves. It is very important that a large amount of air diffused in the ceramic material is likely to flow outside the material itself, preventing it from collecting inside the pressed plate and forming empty spaces. In fact, once the pressure exerted by the plates has ceased, such empty spaces can expand and cause the rupture of the pressed plates. In the case where it remains trapped in the pressed board without causing its cracking, it may expand during the firing step, however resulting in cracking of the board.

At present, in order to enable the evacuation of air from the pressed material, the pressing cycle, in particular the compression step of the layers and the release step of the panels, is carried out relatively slowly in a gradual manner. Obviously, this leads to an increase in production time.

Disclosure of Invention

The object of the present invention is to provide a press which is capable of improving the characteristics of currently available presses.

The main advantage of the press according to the invention is that it enables a much more efficient evacuation of air during the pressing of the material than is currently required.

Drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of an embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

fig. 1 shows a schematic partial view of a section of a first embodiment of a press according to the invention, taken in a plane perpendicular to the horizontal longitudinal direction X;

fig. 2 shows a schematic partial view of a section of a second embodiment of the press according to the invention, taken on a plane perpendicular to the horizontal longitudinal direction X;

fig. 3 shows a schematic partial view of a section of a third embodiment of the press according to the invention, taken on a plane perpendicular to the horizontal longitudinal direction X;

fig. 4, 5 and 6 show views from above of the embodiments of fig. 1, 2 and 3, respectively.

Detailed Description

The pressing apparatus of the present invention comprises: a lower plate 12 provided with a pressing surface facing upward; and an upper plate 11 provided with a pressing surface facing downward. The two pressing surfaces have a rectangular contour in plan view, the sides of which are arranged parallel to the longitudinal direction X and the transverse direction Y.

The two plates are activated to move closer and further away from each other, thereby performing pressing of the deposited layer L in the form of a layer of ceramic material.

The upper plate 11 can be provided, at the bottom, with a shaped element F, directly or indirectly associated with the pressing surface, configured to define a containing profile on the layer L. However, the presence of the shaped element F is not essential.

The device also comprises a conveyor belt 13 having a movable stretch 14 provided with an upwardly facing support surface. The movable extension 14 is at least partially disposed between the upper plate 11 and the lower plate 12. The conveyor belt 13 and its movable stretch 14 are therefore arranged above the lower panel 12 and below the upper panel 11. The movable portion 14 of the conveyor belt 13 is movable along the longitudinal direction X to feed the layer L of material to be pressed into the space comprised between the two

plate members

11, 12. The layer L to be pressed is deposited upstream of the two plates on the conveyor belt 13, using means known to those skilled in the art and not shown in detail. The conveyor belt 13 is activated by rollers arranged with respect to the path to be followed, in a manner known in the art.

The pressing device may be equipped with an upper belt 18 provided with a movable stretch arranged at least partially between the conveyor belt 13 and the upper panel 11. In this case, the forming element F is applied to the upper belt 18. The active part of the upper belt is movable along the longitudinal direction X according to the active stretch 14 of the conveyor belt 13. At least for the stretches arranged at the

plates

11, 12, and partly upstream and downstream thereof, both active portions are parallel to the longitudinal direction X. The upper belt is also activated by rollers arranged with respect to the path to be followed, in a manner known in the art.

The lower plate 12 and the upper plate 11 define integrally a pressing compartment V in which the pressing of the load L is carried out.

The upper plate 11 and the lower plate 12 are movable towards and away from each other between a loading position, in which the two plates are located at a greater distance, and a pressing position, in which the two plates are located at a shorter distance.

When the

plates

11, 12 are in the loading position, the layer L can be fed to the pressing compartment V by means of the conveyor belt 13. The upper belt, if present, moves in synchronism with the conveyor belt 13, bringing any shaped elements F into a central position for pressing. To press the load L, the plate is moved towards the pressing position and a gradual compression of the layer L is performed. Preferably, but not necessarily, the upper plate 11 remains fixed, while the lower plate 12 is movable.

The two

side walls

21, 22 are arranged parallel to the longitudinal direction X so as to laterally define, together with the two

plates

11, 12, a pressing compartment V. The pressing compartment is thus delimited at the top and bottom by the two

plates

11, 12 and at the sides by the two

side walls

21, 22. The two side walls are arranged substantially vertically and adjacent to the sides of the

plate members

11, 12.

The

side walls

21, 22 have a stabilizing and/or reinforcing function with respect to the structure of the press. For example, in a preferred embodiment, the press comprises a plurality of ribs, i.e. flat annular elements, which are arranged parallel to each other in a vertical plane. The ribs are aligned along the longitudinal direction X so that the respective openings are also aligned along the longitudinal direction X to define, as a whole, a tubular space within which the

plate members

11, 12 are housed. In this way, the ribs support the pressure exerted by the

plates

11, 12. In this embodiment of the press, the

side walls

21, 22 are connected to the ribs and help to support and/or constrain the ribs to each other.

The

side walls

21, 22, close to the side surfaces of the

plates

11, 12, limit or practically prevent a sufficient air flow in the transverse direction at the outlet from the pressing compartment V, in fact enabling the air flow to be discharged only through the inlet and outlet regions of the press. For example, each side wall is in the form of a plate having a height, measured along a vertical direction, greater than the distance separating the pressing surfaces of the

plates

11, 12 in the loading position, and a length, measured along a horizontal direction parallel to the longitudinal direction X, greater than or equal to the length of the pressing compartment V.

In the embodiment shown in figures 1, 2 and 3, the upper plate 11 is preferably, but not exclusively, provided with a projecting profile 11a on each side. The

side walls

21, 22 are alongside the projecting profile 11a of the upper panel and are kept at a distance from the upper panel 11 so as to define a lateral space C substantially comprised between the pressing compartment V and each

side wall

21, 22. However, the presence of the protruding profile 11a is not necessary, since it is possible to arrange the upper plate 11 with substantially smooth sides adjacent to the

side walls

21, 22.

Advantageously, at least one of the side walls 21 has a plurality of through holes 210 which place the pressing compartment V in communication with the external environment. Due to the presence of the through holes 210, the air ejected from the material during the compression step does not saturate the pressing compartment V, i.e. it does not increase the pressure inside the pressing compartment V, but can be vented to the external environment. This means that there are substantially no empty spaces or air pockets in the pressed board.

In the embodiment shown, the through hole 210 faces a lateral space C, which in turn communicates with the pressing compartment V.

The through hole 210 may be provided with protruding mouth portions 211 protruding from the

respective side walls

21, 22 towards the pressing compartment V. Preferably, but not necessarily, the mouth 211 is open near or at least partially inside the pressing compartment V. For example, in the embodiment shown, the mouth 211 projects towards the pressing compartment V above and beyond the lateral edge 15 associated with the conveyor belt 13, as will be described in more detail below.

Preferably, but not necessarily, the through holes 210 may be connected to a collection manifold, for example a single duct, which also enables the particles and/or granules dragged by the air leaving the pressing compartment V to be collected through a respective connecting duct 212. Furthermore, the through holes 210 or possible manifolds may be connected to a suction circuit to further facilitate the evacuation of the air ejected from the layer of ceramic material during the compression step.

In the embodiment shown, the conveyor belt 13 comprises two lateral edges 15 parallel to the longitudinal direction X and projecting from the conveyor belt 13 by a predetermined height. Such a side edge is described in publication WO 2017149484. Preferably, the side edges are made of an elastically deformable material.

The side edges 15 have the function of preventing particles or parts of the layer L from escaping from the pressing compartment V and being deposited in undesired areas. In the movable stretch 14 of the conveyor belt 13, the side edges 15 project upwards to the side of the pressing compartment V. The side edges 15 may, for example, be arranged in the lateral regions of the conveyor belt 13. During the pressing step, the side edges 15 are compressed between the plates, elastically deformed and laterally closing the pressing compartment V.

To facilitate the discharge of air, the side edge 15 is provided with a plurality of through holes 150. Also in the pressing position of the

panels

11, 12, in which the side edges 15 are in contact with the upper panel 11, such through holes 150 maintain a communication channel between the pressing compartment V and the outside, to enable the evacuation of air.

In the embodiment shown, the through hole 150 maintains a communication channel between the pressing compartment V, the lateral space C and the through hole 210. Preferably, the advancement cycle of the conveyor belt 13 is controlled so that the conveyor belt 13 stops for the pressing step at a position where the through hole 150 of the side edge 15 is aligned with the through hole 210 of the

side wall

21, 22. This aligned position promotes the outflow of air from the pressing compartment V.

Claims

1. A press for granular or powdered material, comprising: an upper plate (11) and a lower plate (12) movable towards and away from each other between a loading position in which the upper and lower plates are at a greater distance and a pressing position in which the upper and lower plates are at a shorter distance; -a conveyor belt (13) movable along a path, having at least one movable stretch (14) parallel to the longitudinal direction (X) and arranged between the upper plate (11) and the lower plate (12); two side walls (21, 22) arranged parallel to the longitudinal direction (X) so as to laterally define, with the upper and lower panels (11, 12), a pressing compartment (V): characterized in that at least said lateral wall (21) has a plurality of through holes (210) which place said pressing compartment (V) in communication with the external environment.

2. The press according to claim 1, wherein the through hole (210) is connected to a collection manifold.

3. The press according to claim 1, wherein the through hole (210) is connected to a suction circuit.

4. Press according to claim 1, wherein said through holes (210) are provided with exit portions (211) that protrude from the respective side wall (21, 22) towards the pressing compartment (V).

5. Press according to claim 1, wherein the upper plate (11) is provided with a projecting profile (11a) on each side; said side walls (21, 22) being alongside said protruding profile (11a) of said upper panel and spaced apart from said upper panel (11) by a distance such as to define and include a lateral space (C) between said pressing compartment (V) and each of said side walls (21, 22).

6. Press according to claim 1, wherein the conveyor belt (13) comprises two side edges (15) parallel to the longitudinal direction (X) and projecting at a predetermined height from the conveyor belt (13), wherein the side edges (15) are provided with a plurality of through holes (150).

7. The press according to claim 6, wherein the conveyor belt (13) advances according to an advancement cycle having a stop step during pressing at a position where the through holes (150) of the side edges (15) are aligned with the through holes (210) of the side walls (21, 22) of the pressing compartment (V).