FR2517295A1 - PROCESS AND PLANT FOR COOKING CERAMIC MATERIALS - Google Patents

Abstract

THE INVENTION CONCERNS THE COOKING OF SERIAL CERAMIC ARTICLES WITH CONTINUOUS CIRCULATION OF TRANSPORT PLATES INTENDED TO SUPPORT THE ARTICLES ALONG A CLOSED CIRCUIT THROUGH THE COOKING OVEN, WITH LOADING STATIONS 11, 11 AND UNLOADING 12, 12 TRANSPORT PLATES; PROVIDED FOR A T CONVEYOR DEFINING THE CLOSED CIRCUIT, CONSISTING AT LEAST IN PART OF PAIRS OF LATERALLY SPACED BELTS, WITH MEANS OF TRANSFER 4 OF THE PLATES BETWEEN TRUNKS OF THE CONVEYOR.

Description

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  4 l. Method and installation for firing ceramic materials

  at________________________________________________________

  Processes are known for manufacturing ceramic articles in series, comprising a firing operation intended to completely remove the water retained in the clay components used to convert them into the corresponding anhydrous compounds.

  used, for reasons of energy savings, in part

  particularly with regard to their consumption when they are started up, most often operate continuously in

  installations for the production of ceramic materials.

  On the contrary, the operations carried out upstream and / or downstream of the oven, such as the shaping and the preparation of the raw shapes for cooking, or the evacuation of the articles of series after their cooking, their storage and their packaging, are operations that are only performed

  during working hours, and therefore intermittently

  attempted. This is why, in installations for the production of ceramic articles, we have proposed and used

  temporary storage systems, which allow the storage

  emulation of the raw forms obtained during the shaping stage and their continuous routing towards the ovens or, conversely, the continuity of unloading of the articles from the baking ovens and their storage, even during periods of inactivity upstream and downstream facilities, periods which depend on interruptions

  of operation, voluntary or not, of said installations

tions.

  With particular regard to the arti-

  ceramic plate keys, which will be conveniently called

  subsequently tiled, such storage systems

  may include specially designed carts

  such as those described in other applications for

same applicant's patents.

  -2- During the baking treatment in an oven, the raw forms of the tiles, which are brought in their uncooked state (molded, extruded, etc.) are transported through the oven in more or less numerous groups on "trays" or transport plates provided for this purpose, the role of which is to preserve the conformation of the raw forms

by preventing their deformation.

  In the cases envisaged above of interruptions of the installations located upstream and downstream of the ovens, said transport plates, as well as the tiles which they transport, are unloaded on the trolleys

  temporary storage mentioned, where they are left for

  throughout the duration of the interruption, so that they

  are removed from the active cycle of the process.

  Thus the continuity of the treatment cycle in the oven during such periods requires that a large quantity of transport plates is available for the continuous supply of new loads of tiles to be treated to the oven, this availability.

  having to take into account the possible extension of the inactivity

  tivity of certain parts of the installation Of course, such significant availability of transport plates

  entails costly investments.

  Consequently, the need for trolleys for the temporary storage of the raw forms also increases, the capacity of these being completely saturated by the accumulation of transport plates during said interruptions. This increase in the requirements for storage trolleys causes an additional increase in

investment costs.

  Another disadvantage of the use, during said interruptions, of a large number of transport plates is the increase in energy consumption due to their heating during the baking treatment.

in the oven.

  A first object of the invention is to provide _ 3 _ a method and an installation for firing ceramic materials, in particular ceramic tiles, which allow the treatment cycle to be carried out continuously regardless of the duration periods of interruption of the process upstream or downstream of the baking treatment station, and which significantly reduces the

needs for transport plates.

  Another object of the invention is to provide a method and an installation for firing ceramic materials which make it possible to produce substantial

  energy savings during the processing cycle

  seriously. Another object of the invention is to provide an installation for firing ceramic materials which can also absorb certain imbalances in the operation of the device, due to the possibilities

accidental interruption.

  A significant object of the invention is to

  propose an installation for cooking such materials

  ramics implying lower investment costs, not only because of a reduced need for plates of

  transport, but also in temporary storage trolleys

  porary. To this end, a first aspect of the invention relates to a process for firing series ceramic articles, characterized in that raw forms to be treated are brought to a furnace on transport plates, said plates transport being arranged to be conveyed continuously along a closed circuit path, said transport plates are passed, transporting

  cooked items, through at least one unloading station

  automatic management of the articles, said ar-

  said transport plates (\ to at least one automatic loading station to load the raw forms to be processed there, and pass them again

  said transport plates through said oven.

  Another aspect and the invention relates to a

  installation for firing ceramic materials,

  nant a furnace-treatment, said ceramic materials being transported and conveyed on a plurality of transport plates, characterized in that it (_J

  includes an apparatus arranged to continuously move the

  said transport plates along a closed circuit path also passing through said oven, and means, the

  along the closed circuit route, for charging and discharging

  manage the ceramic material transport plates.

  The invention is better understood on reading

  of the following description of a pre-

  fairy but not limiting in which reference is made to the accompanying drawings, in which

  Figure l is a schematic top view of the ins-

tallation according to the invention,

  Figure 2 is a side elevational view shown

  schematically both the installation of Figure 1, observ-

  from the side of the loading and unloading means

gement,

  FIG. 3 represents the means for loading the plates

  transport according to the invention, observed transversely

  in the direction of movement of the plates,

  Figure 4 is a top view of the means of trans-

  fert between the various parts of the conveyor according to the

  vention, Figure 5 is a side elevational view schematically showing the means of Figure 4 during their pickup movement of the transport plates, Figure 6 is a top view illustrating the rotary movement of the transfer means of Figures 4 and 5 , and

  Figures 7 and 8 schematically illustrate the mold

  transfer means for depositing the plates

  transport on an adjacent part of the conveyor.

  With reference to the drawings, the reference numeral 1 designates a baking oven to which the process of the invention -5- can be applied, and which can be incorporated into an installation according to the invention Although it can be applied to any type conventional oven commonly used, the invention applies preferably to ur, folur single cooking, one or more channels, in which are provided a plurality of chambers or cooking channels, which can be arranged side by side or superimposed, through which roller conveyors bring ceramic articles of manufacture,

  hereinafter called carraux, for purposes of illustration.

  The installation of the invention firstly comprises an apparatus intended to permanently move transport plates along a closed circuit through the furnace 1, and feeds it and successively evacuates all the channels of an furnace multichannel, according to a program

  predetermined or by command as we will see later.

  The apparatus for moving the plates along the closed circuit comprises a conveyor T connecting, along a path outside the oven, the oven outlet 2 to the inlet of the oven 3, via a number of stations

  treatment, as will be seen in more detail later.

  rement. The conveyor T, although it may be of the belt conveyor or roller conveyor type, preferably comprises, according to an advantageous embodiment of the invention, pairs of laterally spaced belts, such pairs of belts being driven and suitably supported by pulleys mounted in the frame of the apparatus The transport plates are supported by the respective pairs of belts so that their lateral parts project beyond the two belts. The apparatus for moving the transport plates comprises, according to the invention, between different sections of the conveyor having between them an angle or a change in level 4 of means for transferring the

  transport plates between said different sections.

  -6- Such transfer means, shown schematically in Figures 4 to 8, include a fork 5 rotatably mounted around a vertical hinge 6 The movement

  rotation is ensured by drive means 7.

  The fork 5 is integral with a sleeve 8 cooperating with an upright 9 of the frame of the device. Drive means (not shown) move the sleeve 8 along the upright 9, to impart to the

  fork 5 a vertical translational movement.

  The transverse dimension or spacing of

  the fork 5 is provided so as to allow cooperation

  tion of the fork with the pair of covo- belts

  yage of the sections between which the transfer takes place, the fork being able to move in translation up or down, through the spaces between the pairs of belts or outside of them, to cooperate with said parts of the transport plates that protrude at

the outside of the belts.

  With reference to FIGS. 5 to 8 in particular,

  the succession of movements illustrated includes the movement

  cement to the top of the fork 5, which cooperates with the projecting lateral parts of the transport plates arriving on the section P of the conveyor and picks up these by lifting them above the plane of the conveyor Then the fork rotates 900 to become parallel to the next section R of the conveyor, and is then moved down During the downward movement of the fork 5, the transport plates are recovered and retained by the end portion of the section R of the conveyor passing between the arms of the fork, allowing them to move

along the preset route.

  Advantageously, the end part of at least one of the sections between which the means of

  transfer 4 operate, in the embodiment shown

  felt here, the end part of the section R, is designed in the form of a mobile end part 10 -7 - which is arranged to move vertically, so

  to obtain more flexible cooperation with the fork 5.

  Conventional drive means (not shown) are provided to control the movements of said movable arm, for example by acting on a sleeve

  secured to arm 10 and guided along an upright identi-

  than that described for the translational movement of the fork 5, to allow the relative movements between the fork and the movable arm and return said arm to its position aligned with the remaining part of the section R.

  In the embodiment of the installation according to the

  vention shown in Figures 1 and 2, two of these means of trans-

  ferts are shown respectively between sections P and R and between sections R and S of the conveyor It is clear that there can

  have several places where the presence of such means of trans-

  fert is necessary, depending on each specific route that a

  conveyor according to the invention must be able to follow.

  In particular, the transfer means 4 described above are also used at the input 3

  and at the outlet 2 of the multichannel oven 1 (but not shown

  felt on the drawings), arranged to allow the char-

  handling and unloading of the supporting transport plates

  both the tiles from the various superimposed levels

from the oven.

  Along the path of the closed circuit of the transport plates, and in particular on the section R of the conveyor, means 11 are provided for loading the tiles to be treated on the transport plates, and means 12 for respectively discharging the cooked tiles. Transport plates Advantageously, more than one of these respective loading and unloading means can be used, operating alternately or as back-up during interruptions due to operating incidents or during maintenance, etc. In this case, as shown in the figures, it is possible to insert the auxiliary loading means 11 'and the auxiliary unloading means 12' into the closed circuit of transport plates by placing them on bypass sections U of the conveyor The means loading 11, for example, are described in more detail with reference to Figure 3 As shown in this figure, the tiles to be treated 13, arriving on a conveyor device feed eur E also comprising a pair of belts, are placed at the loading station above a support element 14 which can be moved up and down by suitable means, such as for example a cam (not shown). When it is moved upwards, the support element 14 lifts the pane at the level of the upper surface of the loading plates 15 brought on the

  conveyor T to the loading station 11 A rack

  1st 16, driven for example by a chain, itself driven by a toothed wheel coupled to a motor, is provided to move the tiles to be treated supported by the support element 14 to transfer them to the

plates 15.

  Of course the movements of the conveyor T at the loading station 11, of the conveyor E, of

  the support element 14 and the rack 16 are conve-

  quite synchronized, for example thanks to a photocell control, to ensure the sequence

described in an appropriate order.

  The unloading station includes unloading means 12 and is designed exactly in the same way as the loading means 11 described above, except that the rack is arranged in a location symmetrical to that of the loading means 11, so as to ensure, during its active stroke, the transfer of the cooked tiles from the transport plates 15 to an identical support element 14 associated with a belt conveyor F intended for conveying the tiles

17295

  -9- cooked to storage stations provided for this purpose Advantageously, the apparatus intended to move the transport plates 15 according to the invention comprises, on the path of the closed circuit of the transport plates, a buffer storage station capable of absorbing imbalances due to accidental interruptions of the device and ensuring continuity of supply for the transport plates loaded with tiles to be treated

to the treatment furnace.

  Advantageously, the buffer storage device 17 comprises a tunnel chamber 19 in which is placed an auxiliary conveyor with an endless chain 18 connected to a plurality of containers each comprising several shelves intended to receive a substantial number of transport plates loaded with their tiles to be treated In the event of breakdowns or interruptions on the conveyor T, this

  storage unit is put into service and, by moving

  cement of the chain conveyor 18, can ensure the conti-

  supply of transport plates and tiles to be treated from the outlet of the tunnel chamber 19 to the section in operation of the conveyor T or then to a branch section of the conveyor (not shown) to route them to the oven 1 Depending on the size of the storage unit and according to its capacity, it will be able to cope with longer or shorter periods of interruption of the main conveyor T. Advantageously, the tunnel chamber 19 of the storage unit 17 is connected by a toy 20, to the oven 1, so as to convey the exhaust gases

  hot from oven 1 to storage unit 17.

  Thus the tunnel chamber 19 of the storage unit 17 also acts as a drying device intended to preheat and dry the tiles to be treated before

  their introduction into the oven 1 For a description

  - More detailed description of a possible embodiment of the storage and drying unit 17 usable in the present device, reference may be made to the Italian patent.

No 951 790.

  Of course, as indicated above, it is possible to provide, on the closed circuit path,

  transport according to the invention, several storage units.

  We can clearly see from the description

  above how the process, design and function-

  nement of the installation of the invention are implemented, and what are the advantages Thus thanks to the continuous recycling of the transport plates a quite smaller quantity of these is necessary, in particular when the installation operates at times of the day o the preparation devices located upstream of the baking oven and the storage units located downstream of it are not in service as well as an entirely smaller quantity of storage media, in the measure where are the tiles

  which are stored and no longer the transport plates.

  On the other hand, the continuous recycling of transport plates, unlike previous installations

  o they were immobilized for storage during the

  so-called interruptions, prevents these from being completely cooled down to room temperature, which allows

  energy savings for their successful heating cycles

  as they pass through the baking oven 1.

  Note that the above description

  relates to a preferred embodiment of the method and of the installation according to the invention, and that all the possible variants conceivable by those skilled in the art are included

in the context of the invention.

  By way of example, the means for transferring the transport plates may include, instead of the fork described,

  a curved conveyor part having the appropriate radius of curvature

  prayed and arranged to cause displacement in vertical translation

  wedge, in order to connect the various sections of the conveyor between them

  which transfer is to be carried out.

11 -

Claims (9)

  1 Process for firing series ceramic articles, characterized in that raw forms to be treated are brought to a furnace on transport plates, said transport plates being arranged to be conveyed continuously along a closed circuit path, said transport plates are passed, transporting   cooked articles, through at least one unloading station   automatic management of the articles, said ar-   said transport plates are brought to at least one automatic loading station to load the raw forms to be processed there, and said passages are passed again   transport plates through said oven.   2 Method according to claim 1, characterized in that the transport plates are passed, on their closed circuit path, through a buffer storage station arranged to continuously bring said transport plates, transporting raw forms to be treated , towards   said oven in the event of interruptions in said circuit.   3 Installation for cooking ceramic materials   mics, comprising a treatment furnace (1), said ceramic materials being transported and conveyed on a plurality of transport plates, characterized in that it comprises an apparatus arranged for continuously moving said transport plates along a path in closed circuit also passing through said furnace, and means, along the closed circuit path, for loading and unloading the plates for transporting ceramic materials.   4 Installation according to claim 3, charac-   characterized in that the apparatus arranged for moving said transport plates comprises a conveyor (T) comprising, over at least part of its length, pairs of conveyor belts laterally spaced from one another. Installation according to claim 4, 5 - 12 characterized in that the apparatus designed to move the transport plates further comprises means <4) for transferring said plates between sections of said conveyor arranged in different directions or at different levels l 'from one another, said transfer means comprising a fork element (5) arranged to be driven in rotation about a vertical axis (6) and in translation (8,9) along said axis to pick up or deposit on said sections of the conveyor said plates transport.   6 Installation according to claim 5, charac-   characterized in that the sections (PRS) of the conveyor arranged in directions or at different levels one of   the other include said pairs of conveyor belts   laterally spaced apart, said fork element being arranged to be inserted with said pairs of belts during its alternating movements in translation 7 Device according to claim 5 or 6   characterized in that said transfer means includes   There is also, on at least one of said sections of the conveyor, a movable end arm (10) arranged to cooperate with said fork (5) by a displacement in   translation with respect to it.   8 Device according to any one of the claims   cations 3 to 7, characterized in that said means of loading (11) and unloading (12) of said ceramic materials each comprise a conveying device <E) of the articles, a support element cooperating with said conveyor being arranged to pick up said articles and put them in an adjacent and coplanar position relative to said transport plates supplied on said c 1 nvyeor, and rack means (16) arranged to transfer said articles to   from the support element towards the said transfer plates.   9 Installation according to claim 8, charac-   characterized in that said conveying apparatus comprises a pair of laterally spaced conveying belts 13 - one from the other, and in which said support element is movable vertically under the action of a cam, in the space separating said pair of belts, for lifting the articles from said belts when it is moving upwards, and depositing said articles on said   belts when moving down.   Installation according to any of   Claims 3 to 9, characterized in that it comprises   in addition, along said closed circuit, a buffer storage unit (17) arranged to continuously convey to said furnace said transport plates, transporting said ceramic articles, in the event of interruption on along said conveyor.   Installation according to claim 10, charac-   characterized in that the buffer storage unit (17) comprises a tunnel chamber (19) inside which is provided an endless auxiliary conveyor (18) supporting a plurality of containers arranged to receive a certain quantity of the plates transport, transporting ceramic articles, and for conveying them towards the exit of said chamber in tunnel in order to bring them towards said oven.   12 Installation according to any of   Claims 3 to 11, characterized in that it comprises   in addition, along said closed circuit, between said loading means and said oven, a drying unit arranged to preheat and dry the raw forms of the articles to be treated, said drying unit being swept by the exhaust gases from said supplied oven. by piping link (20).   13 Installation according to claim 12, characterized in that said storage unit and said   drying units are one and the same unit.