ES2946749T3 - Device for supplying at least one pulverulent substance, particularly for ceramic part forming presses - Google Patents

Abstract

Device for supplying at least one pulverulent substance, particularly for ceramic part shaping presses, with progressive discharge or supply means of the pulverulent substance to the alveoli of the lower female mold (19), comprising a frame (1) or frame external support perimeter for one or more receptacles (2) which have an upper mouth (4) with a substantially rectangular area, a lower mouth (5) whose surface area is smaller than that of the mouth (4), a truncated-pyramidal shape inverted, and a height greater than the thickness or height of the frame (1). Said receptacle (2) or receptacles can be removable and movable horizontally to be located in different positions inside the frame (1), which incorporates hooking plates (6) movable and fixable in different positions for this purpose. And procedure for the operation of said device in a press for forming ceramic pieces.

Description

DESCRIPTION

Device for supplying at least one pulverulent substance, particularly for ceramic part forming presses

Technical field of the invention

The present invention falls within the technical field of devices for the supply and distribution of pulverulent substances for the manufacture of flat ceramic articles such as wall tiles and paving tiles that require the forming of the raw material that composes them in presses.

Background of the invention

In the manufacture of flat ceramic articles, such as tiles, slabs and tiles, it is common to use forming presses that include a lower bed and an upper press traverse, penetrating molds made up of two half-molds, an upper male one provided with a plurality of upper compaction punches, and another lower female with a matrix of housings or alveoli, also provided with a plurality of lower compaction punches, in which a raw or semi-processed pulverulent substance is placed, such as earth or clay, for example. from which, through the pressing action of the punches, compacted pieces of a material called biscuit are formed, from that moment on, which are subsequently subjected to further treatments, such as glazing, decoration and firing to obtain flat ceramic articles. corresponding finishes.

For the production of the compacted pieces, the most homogeneous possible load of the pulverulent substance is required in the cavities of the matrix in order to obtain a pressed body with a density with the least possible variations, since this later affects the quality of the article. matching ceramic finish. In industrial practice it is very difficult to achieve a completely homogeneous charge in all the alveoli of the matrix of the female mould.

In a stage prior to compaction and molding, the pulverulent substance is stored externally and it must be supplied and distributed uniformly on the matrix provided with accommodations or receiving cells (alveoli) of the female molds of the press.

For this, a filling hopper of the device for supplying and distributing the pulverulent substance is usually used, which comprises at least one mobile carriage or conveyor provided with a supporting frame and various crossbars or projections to serve as support and move on the mold matrix. what is usually called a grill (due to its similarity with said utensil), and various elements that are used in the process of manufacturing and obtaining the cake, such as, for example, and additionally, one or more scrapers, combs or blades that serve as elements dragging excess pulverulent substance that may remain on the surface of the female mould, and/or a pusher that, in an anterior position with respect to the grid with respect to a direction of advancement, moves a previously shaped biscuit horizontally by pushing, out of the area of the alveoli in which it has been pressed, leaving the latter free to receive a new charge of powdery substance.

The aforementioned grid essentially consists of a perimeter frame in whose internal area there is a grid of various shapes (parallel lines, grids...) with substantially the same or less height or thickness than that of said perimeter frame. This grill is incorporated into the mobile cart or transporter at the top and by various means of fitting or connection, generally by means of clamps or claws in the shape of an inverted "U", in such a way that the grill is held by gravity and movably fixed to the frame. carrier.

In a first stage of manufacturing, the grid and the conveyor carriage are positioned horizontally and superiorly in an area immediately before the location of the first of the alveoli of the matrix of the female mould, and in said position the powdery substance stored externally is deposited. and loaded on the grill; the lower part of the grill is completely supported and flush with the upper surface of the matrix of the female mould, with a finish or elements generally flat or preferably in the shape of an inverted "L" on the bottom, called scrapers among others. denominations, made of a resistant material and suitable to withstand abrasion and friction inevitably derived from friction and sliding between surfaces in direct contact.

In a second stage, the conveyor carriage begins its displacement and horizontal advance in one direction towards and over the location of all the alveoli of the matrix of the female mould, in such a way that it positions the grid completely on said alveoli, whose compaction punch The bottom is in a raised position and flush with the die surface of the female mold. Once said position has been reached by the grid and its load of pulverulent substance, the lower compaction punch descends allowing the entry by gravity of the pulverulent substance into the corresponding alveoli.

In a third stage, and once the load has been supplied to the alveoli, the conveyor carriage begins a backward horizontal movement to its initial position, during which the excess pulverulent substance deposited in the previous phase on the alveoli is removed by dragging and protruding from its upper edge.

Said stage ends with the arrival of the transporter car and the grid to the initial starting position in the first stage.

The supply and distribution of the pulverulent substance is carried out by dragging the mobile carriage or transporter that moves the loaded grid to the matrix of the mold and the mere action of gravity on said substance that is deposited in a single phase and in a uniform way. joint over the entire surface of all the alveoli, and a subsequent dragging and sweeping movement of the mobile carriage over the matrix of the mold.

This determines that the load and the distribution of the pulverulent substance throughout the alveolus is of an irregular density and homogeneity, since at present it presents irregularities in the same alveolus, as a consequence of the different quantity and density of the pulverulent substance in a given point differs from that of another point, depending on the amount and density of substance that in the previous process of loading the rack from external storage and in the first stage has been disposed on said rack, and the fact that the transfer to the alveoli occurs in blocks and units of time over all the alveoli and over the entire surface.

DE 27 30 881 A1 discloses a coupling system that simply allows the assembly of a single element in a predefined fixed position.

IT 1238782 B comprises a receiving element that is detachable and cannot be moved inside the external perimeter support. This prior art document does not disclose that the receiving element is higher than the thickness or height of the external perimeter support. Nor does it disclose the coupling plates described.

JP 2000 20202816 A discloses a device of at least one powdered substance according to the preamble of claim 1, which however does not comprise coupling plates of a receiving element.

Description of the invention

The object of the present invention is to facilitate assembly in a variety of sizes, overcoming the drawbacks of the state of the art detailed above, by means of a device for supplying at least one pulverulent substance, particularly for ceramic part shaping presses, according to with claim 1, which dispenses with the conventional grill and replaces it with means that allow a progressive supply and gradual distribution of the pulverulent substance by means of a continuous flow by curtain in the alveoli throughout the aforementioned second stage and with the additional difference of that instead of what is referred to with the conventional procedure in said second stage, according to the invention, the lower compaction punches are in a rest position from the beginning of the second stage, leaving the alveoli exposed to receive the powdery substance according to and from the moment the conveyor carriage and the device object of the invention begin to advance in the second stage, and during the entire phase of its horizontal movement.

With all this, a practical advantage is obtained derived from said progressive, gradual and successive loading of the cavity of the alveoli, which produces a greater homogeneity of the density of the pulverulent substance that remains deposited in them in a more uniform and controlled way. , with a better result of the subsequent compaction to which said substance will be subjected.

Brief description of the figures

Aspects and embodiments of the invention are described below on the basis of schematic drawings, in which

Figure 1 is a top perspective view of the device object of the invention;

Figure 2 is a top plan view and side elevations of the device object of the invention; Figure 3 is a top perspective view of the progressive discharge means comprising the device object of the invention and an explosion of some parts thereof;

Figure 4 is a top perspective view of the frame or external perimeter support frame of the device object of the invention, of various elements that it comprises, and an explosion of some parts thereof;

Figure 5 is a top perspective view of the device object of the invention and of a pusher comprising in one of its embodiments in a position before it with respect to a direction of advance (A);

Figure 6 is a schematic section in side elevation of a press for forming ceramic pieces in which the device object of the invention is positioned in the first manufacturing stage;

In these figures there are references that identify the following elements:

forward direction

1 frame

2 receptacle

3 longitudinal linear strips

4 upper mouth of the receptacle

5 lower mouth of receptacle

6 hook plates for the receptacle

7 outer ribs of receptacle

8 means of locking and unlocking the hooking plates

9 pusher

10 scratching posts

11 Longitudinal linear scraper inside the frame

12 plate

13 closing or lid elements

14 grooves in the upper mouth of the receptacle

15 through element to immobilize the strips

16 claws or clamps

17 hopper filling device

18 upper male mold

19 lower female mold

20 press bench

21 press traverse

22 housing, cells, alveoli

23 longitudinal linear element of the free end of the pusher

Modes of carrying out the invention

The device object of the invention is intended to be used in presses for shaping ceramic pieces that comprise at least one mobile carriage or transporter provided with a supporting frame and several crosspieces or projections to serve as support and move the lower female mold on the matrix ( 19); the device itself object of the present invention and other additional elements.

The device for supplying at least one pulverulent substance, particularly presses for forming ceramic pieces whose embodiment is shown in figure 1, comprises a frame (1) or external perimeter frame that serves as a support inside for different elements, which are used in the process of manufacturing and obtaining the cake, such as, for example, and additionally, one or more scrapers, combs or blades that serve as drag elements for excess powdery substance that may remain on the surface of the lower female mold (19), and/or or a pusher that is in an anterior position with respect to the grid with respect to a direction of advance (A) of the device during its operation in the forming press.

Inside said frame (1) there are, among other things, progressive discharge means for at least one pulverulent substance, configured in one or more receptacles (2), four in the embodiment shown in Figure 1, which They have an upper mouth (4) with a substantially rectangular area, a lower mouth (5) whose surface area is smaller than that of the mouth (4), an inverted truncated pyramidal shape, and a height greater than the thickness or height of the frame ( 1).

Said receptacle (2) or receptacles are removable according to the embodiment shown in the figures.

For this, the receptacle has connection means such as external ribs on its lower external part, in correspondence with grooves on hooking plates (6) arranged inside the frame (1).

Said hooking plates (6) in turn can have means for locking and unlocking their position and are horizontally movable on the inside of the frame (1) in order to be able to locate the receptacle (2) in different positions and enable, for For example, the use and parallel adjustment of several receptacles with different mouth sizes (4).

The frame (1) includes coupling means to an external conveyor element that moves the device object of the invention in the forming press, which can be configured as shown in figures 1 and 2 in the form of claws or shaped clamps. of inverted "U" in various locations on said exterior of said frame (1).

Likewise, and according to the embodiment shown in figure 4, the frame (1) internally includes hooking plates (6) for the receptacle (2), additional fastening means for scraping elements (11) arranged inside the frame ( 1) and in a position behind the receptacle or receptacles in a direction of advance (A), to reinforce the sweeping and elimination of excess pulverulent substance during the operation procedure of the device in the forming press, as well as upper closing or lid elements (13) intended to prevent unwanted or accidental entry of pulverulent substance into certain areas of the device object of the invention.

The device object of the invention, the embodiment of which is shown in figure 3, may comprise one or more longitudinal strips (3) in the mouth (4) of the receptacle (2), which are removably fixed in respective grooves (14) made in the upper ends of the mouthpiece (4), and contribute to a better distribution of the powdery substance inside the receptacle (2).

In turn, said strips (3) can be immobilized with each other by means of a through element (15) that interconnects them with each other and immobilizes them in the body of the receptacle by means of threaded fastening elements that fix the through element (15) on the outside of the receptacle. the sides of the mouth (4) of the receptacle (2), to avoid the accidental exit of the strips (3) from the grooves (14) and also keep them equidistant from each other in their central area, for which the through element, in turn, can incorporate intermediate separator elements with a larger section or diameter than the ones. through connection holes, in such a way that they maintain the strips (3) in the same position relative to each other despite the forces that may affect them during the operation procedure of the device in the forming press.

The device object of the invention according to the embodiment shown in Figure 3, incorporates at the lower mouth (5) of the receptacle (2) scraper perimeter elements (10), some or all of which have a section in the shape of " L" inverted or "V"; they comprise a material capable of supporting friction and fulfill the purpose of adjusting and closing the perimeter of said mouth (5) with the surface of the lower female mold (19); Said scrapers (10) comprise a plate (12) that is preferably removable to facilitate replacement due to wear, to which the aforementioned material capable of withstanding friction is solidly fixed, said material including, for example, polymers.

In the embodiment illustrated in figure 5, the device object of the invention comprises a pusher element (9) with a depth equal to or greater than that of the frame (1), located on the outside of said frame (1) and in a forward position with with respect to a direction of advance (A).

Said pusher (9) presents frontally at its free end at least one longitudinal linear element (23) whose purpose is to successively move the compacted pieces or biscuit already shaped out of the forming press, once every third stage of operation of the object device is finished. of the invention in the forming press, for which, once said third stage is finished, the lower compaction punches ascend to expose said compacted pieces or biscuit during an initial phase of the second stage, and then descend for the forming press. phase of supply and distribution of pulverulent substance to the alveoli (22) that takes place during said second stage in a progressive manner as the device advances over each part of the cavity of the alveoli (22).

Finally, the device object of the invention whose embodiment is shown in figure 6 is fed from a filling hopper (17) that pours on it from an external storage at least one pulverulent substance, and once loaded on the device, This begins its advance in a forming press that includes a lower bed (20) and an upper traverse (21) of the press, penetrating molds made up of two half-molds, one upper male (18) provided with a plurality of compaction punches. upper, and another lower female (19) with a matrix of housings or alveoli (22), also provided with a plurality of lower compaction punches, in which the device object of the invention supplies and distributes at least one pulverulent substance, to from which, by means of the subsequent pressing action of the punches, compacted pieces of the material called biscuit are formed, which are subsequently subjected to treatments such as glazing, decoration and firing to obtain finished ceramic articles.

According to what can be seen from the foregoing, the present invention overcomes the drawbacks of the previously mentioned state of the art and provides an evolutive alternative through an improved device.

Claims (14)

1. Device for supplying at least one pulverulent substance, particularly for ceramic part forming presses, of the type comprising at least one frame (1) or an external perimeter support frame comprising - Means for progressive discharge of at least one pulverulent substance; - in which the means for progressive discharge of at least one pulverulent substance comprise at least one receiving element (2) with an upper mouth (4) and a lower mouth (5); - in which the upper mouth (4) and the lower mouth (5) of the receiving element (2) have a substantially rectangular area; - in which the upper mouth (4) of the receiving element (2) has a greater surface area than that of the lower mouth (5); - in which the receiving element (2) has a height between 40 and 150 mm and is higher than the thickness or height of the frame (1); - in which the receiving element (2) has a shape that is substantially an inverted frustoconical shape; characterized because - the receiving element (2) is removable and immobilizable inside the frame (1) or the external perimeter support frame, - In the internal part of the frame (1) or in the external perimeter support frame, there are some coupling plates (6) for the receiving element (2), - the coupling plates (6) for the receiving element (2) have grooves (14) corresponding to ribs (7) on the outside of the receiving element (2), - The coupling plates (6) for the receiving element (2) can move horizontally and include locking means and unlocking means (8) for fixing them at any point in the horizontal zone in which they move. Device according to claim 1, characterized in that the upper mouth (4) of the receiving element (2) comprises one or more longitudinal linear strips (3) that are removable and immobilizable in the upper mouth (4) of the receiving element (2). , the removable strip(s) (3) are fixed by means of slots (14) in extreme positions of the upper mouth (4) of the receiving element (2), the removable strips (3) are immobilized by means of a through element (15) that connects said strip or strips with lateral elements of the upper mouth (4) of the receiving element (2), the mouth (5) of the receiving element (2) includes below perimeter scraping elements (10) that comprise a material capable of withstanding friction, at least one perimeter scraper element (10) comprising a plate (12). Device according to claim 2, characterized in that a material capable of withstanding friction is integrally fixed to the plate (12). Device according to claims 2 or 3, characterized in that at least one material comprising The perimeter element or elements of the scraper (10) is a polymer. Device according to claim 4, characterized in that the scraper element or elements (10) are removable. Device according to claim 5, characterized in that the scraping element or elements (10) comprise openings corresponding to other openings in the mouth (5) of the receiving element (2) for its connection and fixing by means of through elements (15), in particularly screws or rivets. Device according to any of the preceding claims, characterized in that it comprises a pusher element (9) having the same depth or a greater depth than the entire device, arranged on the outside of the frame (1) and in an anterior position with respect to the direction of advance (A) that presents a linear longitudinal element (23) in front of its free end. Device according to any of the preceding claims, characterized in that the receiving element (2) comprises at least one linear longitudinal scraper element (11) arranged inside the frame (1) in a position posterior to the receiving element (2) with respect to to a forward direction (A). Device according to claim 8, characterized in that the longitudinal scraper element (11) is removable and immobilizable inside the frame (1). Device according to any of the preceding claims, characterized in that at least a part of the interior area of the frame (1) comprises one or more closing or lid elements (13). Device according to claim 10, characterized in that the closure element or elements or cover (13) are removable. Device according to claims 10 or 11, characterized in that the closing element or elements (13) comprise one or more plates. 13. Device according to claim 12, characterized in that the plate or plates have a section in the shape of an "L". 14. Procedure for the operation of a device according to any of the previous claims in a ceramic part forming press, comprising a first stage in which a conveyor carriage is positioned horizontally and superiorly in an area immediately prior to the location of the first one. of the alveoli (22) of the die of the female mould, and in said position an externally stored pulverulent substance is deposited and loaded onto the pulverulent substance supply and distribution device; In a second stage, the conveyor carriage begins its displacement and horizontal advance towards and over the location of the alveoli (22) of the matrix of the female mold, in such a way that it gradually and successively positions the device for supplying the pulverulent substance on different parts. of said alveoli (22), and a third stage, in which the conveyor carriage begins a backward horizontal movement to its initial position, during which the excess powdery substance deposited in the previous phase on the surface is removed by dragging. the alveoli (22) and protruding from its upper edge; Said stage ends with the arrival of the conveyor carriage and the device for supplying and distributing the pulverulent substance to the initial starting position in the first stage, characterized in that the lower compaction punch or punches of the press are in a lowered position at least from the phase of the second stage immediately ^{prior to the first superimposition of the mouth (5) of the receptacle (2) or} receptacles on it or the alveoli (22), in such a way that the entry and distribution of the pulverulent substance in the corresponding alveoli (22) progressively, gradually and successively due to the combined effect of gravity and the horizontal displacement of advance of the supply device, and a supply of said pulverulent substance by means of a constant flow by curtain.