NL2002993C2 - Clay preform production apparatus, used for making bricks, includes hollow punch for forming cavity in clay in moulds and felt covered means for holding preforms during punching - Google Patents

Abstract

At least one hollow punch is used to form a cavity in the clay and has two open ends. A retaining means covered with felt is used to hold the preform during punching. The apparatus comprises a conveyor (2) with mould tools (3) joined together, each tool containing one or more moulds (16) containing one mould cavity; a means (4, 5, 7, 8) for adding a deformable clay to the moulds; and a means for discharging the preforms removed from the moulds. An independent claim is also included for a method for punching a clay preform using the above punch device positioned above the clay moulds.

Description

DEVICE AND METHOD FOR MANUFACTURING CLAY MATERIALS AND PUNCH DEVICES THEREFOR

The present invention relates to a device for manufacturing clay bricks for the brick industry, comprising a circular conveyor joined from mold container parts, wherein each mold container part comprises one or more mold containers with a mold cavity, means for inserting the mold cavities into the mold cavities. applying moldable trays of deformable clay, and means for removing moldings discharged from the mold trays.

The invention furthermore relates to a punching device for removing clay from a green brick, as well as to a method for manufacturing green brick from clay.

From an environmental, energy-technical and cost-technical point of view, efforts are made in all branches of industry to save materials, including the brick industry.

The brick industry can be subdivided into so-called extruder presses, in which clay is extruded, and so-called mold bake presses.

Strand presses produce a kind of clay sausage, which is then cut to the desired stone size. ' Such extruders have the advantage that the mold through which the clay is pressed can relatively easily be provided with a shape such that punctures will be present in the final brick, which results in a material saving. However, because the clay is pressed through the mold like a sausage, the outer surface of the stone, among other things, has been exposed to shear stresses which adversely affect the aesthetic aspects of such a stone.

In so-called mold container presses, to which the present invention relates, moldable clay is pressed into - usually 2 sanded-in - mold cavities of mold containers. The broth formed in the mold container is then unloaded to be dried and baked. The advantage of such mold baking presses is that the aesthetic aspects are improved. Moreover, with mold baking presses, there is the possibility to machine so-called 'hand-molded' stones, which show visual similarity to stones produced in the old-fashioned manual manner. Material saving with mold container presses has, however, to date been limited to arranging protrusions, so-called 'frogs' in the mold containers, as a result of which less clay is required to fill the mold container.

It is desirable to achieve a further saving of material with mold baking presses, so that bricks can be manufactured that require less clay and yet have the aesthetic advantages of bricks manufactured with a mold baking press.

It is an object of the present invention to provide an apparatus and method for manufacturing green bricks from clay for the brick industry with which it is possible to remove clay from a green brick.

The said object has been achieved with the device for manufacturing green bricks for the brick industry according to the present invention, comprising: - a circular conveyor, which is joined from mold container parts, wherein each mold container part comprises one or more mold containers, each with a mold cavity; - means for arranging deformable clay in the mold cavities of the mold containers; and - means for discharging green bricks discharged from the mold containers; Wherein the device further comprises two parts movable relative to each other; - the first part comprising at least one hollow punching member for providing a recess in the clay, wherein the hollow punching member comprises open ends on both sides; - the second part comprising restraining means which are adapted to stop the broth when punching the clay from the broth; and - wherein the restraining means are covered with felt. The restraining means are covered with felt. By covering the contact surface of the retaining means with the clay of the broth with felt, the adhesion of the clay 10 to the retaining means is reduced.

Because the device comprises two parts that are movable relative to each other, clay can be punched out of the green bricks while the desired brick shape is retained. While the first part punches a recess in the clay with a punching member, the second part stops the brigade from which the clay is punched by means of retaining means. As a result, the shape of the green brick is retained, and in particular the green brick is prevented from deforming as a result of shear forces between the punching member and the clay when the punching member moves out of the clay. Without retaining means, this would often result in protruding shapes along the circumference of the punched holes.

Because the punching member is a hollow body with open ends on both sides, in particular a hollow tube, the punching member is able to pass through punched-out clay. Such a hollow punching member is therefore capable of punching recesses from the green bricks in the limited cycle time of a mold container press - which is usually about two seconds per stroke. Because the hollow punching member comprises open ends on both sides, it is possible to dispense with alternative measures to remove the clay from the punching member. Clay included in the punching member can be pushed out of the punching member by means of such a alternative measure, for example by means of a piston on the mold container side. To prevent the clay from falling on the green bricks present in the mold container, however, a time-consuming intermediate step must be carried out. A first possibility comprises temporarily positioning a collecting device under the punching member 5 for collecting the clay punched out of the green bricks. A second possibility comprises moving the punching member above a collecting device for collecting the clay punched out of the green bricks.

Both of the aforementioned options require an intermediate step that cannot be realized in the cycle time of an operational forming container press, and would therefore delay the cycle time, which is undesirable. In addition, the aforementioned options require additional installation space for displacing either the punching member or the collecting device. Moreover, due to its complexity, the required mechanical construction will require more maintenance than the device according to the present invention, and will also consume energy when moving the punch member or the collecting device between each pressing stroke.

Although any cross-section is conceivable, curved shapes without corners have the advantage that clay can be removed from it more easily, which simplifies cleaning operations.

If the punching member were not of hollow design, it would displace the clay at the location of the punching member when it is pressed into the green brigade, whereby a recess in the green brigade is also made. However, the use of such a non-hollow member, which acts as a displacer, requires a very accurate dosage of the clay in the mold container, and is therefore undesirable.

It is noted that the recess can comprise both a full bore of the green brick and a blind hole therein. The clay that is taken out of the green brick results in a saving of materials, which is desirable from an environmental, energy and cost point of view.

Moreover, because the surface area exposed to the warm air in the drying chamber is increased, the green bricks can be dried in a short drying time or possibly at a lower temperature.

According to a preferred embodiment, the device further comprises at least one spring arranged between the first and second part which is adapted to press the retaining means against the mold container when the punching member is at least partially in the mold container.

That is, the punching member is at least partially in a volume enclosed by the mold container, also called mold cavity. This mold cavity of the mold container is intended for receiving and shaping a mold. Because the spring presses the retaining means against the mold container while the punching member removes clay from the mold, the mold cavity of the mold container is delimited at the top by the retaining means, whereby the form of the mold is retained when the clay is taken out.

According to a further preferred embodiment, the device further comprises a frame comprising two parts that are movable relative to each other, wherein the frame is mountable above the mold container in which one or more molds are accommodated, that the frame with the movable parts is relative to the mold container. is movable, the punching member arranged on the first part being movable at least partially in the mold container 30 for punching clay from a molder received in the mold container.

6

Movable in the mold container means that the punching member is movable into the mold cavity of the mold container in which the mold is formed.

According to a further preferred embodiment, the retaining means comprise a plate which is provided with at least one opening through which the punching member can be moved. Because the punching member can move through the plate, clay can be taken out of the blank, while the plate holds the blank around the punching member.

According to a still further preferred embodiment, the device is further provided with supply means for supplying fluid to the felt. The adhesion of clay to the retaining means can be further reduced by moistening the felt layer with a fluid, such as for example oil, in particular biodegradable oil, but also mineral oil. The felt layer moistened with oil prevents sticking of the clay to the plate.

According to a still further preferred embodiment, the mold container is provided with at least one air supply opening.

These air supply openings are arranged in the bottom of the mold cavity in order to prevent a vacuum arising during removal of the clay from the molding, which prevents removal or at least counteracts removal. The openings are therefore located at the locations where the recesses are made in the green bricks, i.e. in line with the stroke of the punching member. In addition, an additional air supply opening can be provided near the edge of the mold container to facilitate the release of the mold from the mold container.

By designing the bottom of the mold containers from an at least slightly elastic material, for example rubber, the punching member can be pressed firmly into the bottom, thereby forming a complete bore in the mold.

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According to a still further preferred embodiment, the punching member is hydraulically or pneumatically driven, which has the advantage that a preset force can be exerted at the lowest point. This is much more difficult to achieve with a purely mechanical drive.

According to a still further preferred embodiment, the hollow punching member is received at its end remote from the mold container side in a collecting body, on which clay passed through the hollow punching member can be collected. The punching member in each case removes a portion of clay from a molding, so that in the case of a hollow tubular punching member cylindrical pieces of clay will be present in the punching member. When the punch member is filled with new clay from the mold container side, cylindrical pieces of clay already present in the punch member are pushed through until they leave the punch member at the end remote from the mold container side. The clay is collected on the collecting body near this end and then discharged for reuse.

According to a still further preferred embodiment, the collecting body is at least partially plate-shaped, and the open end of the hollow punching element remote from the mold container side is received in the plate-shaped collecting body, wherein furthermore a discharge device is provided for discharging clay collected thereon from the plate-shaped collecting body. The discharge device comprises, for example, one or more plates driven via a conveyor, which move the clay collected on the collecting body away from the collecting body.

The open end of the hollow punching member is preferably received at least substantially seamlessly in the plate-shaped receiving body.

The present invention furthermore relates to a device for taking clay out of a broth, comprising two parts movable relative to each other, 8 wherein the first part comprises at least one hollow punching member with open ends on both sides, the punching member serving providing a recess in the clay, and wherein the second part comprises restraining means which are adapted to stop the green brigade when punching the clay from the green brigade, and wherein the restraining means are covered with felt.

In a preferred embodiment of the punching device, the two parts which are movable relative to each other are accommodated in a frame which can be fitted above a mold container in which one or more moldings are accommodated.

In a further preferred embodiment of the punching device, the mold container is part of a device for manufacturing green bricks for the brick industry.

The present invention furthermore relates to a method for punching clay from a molding, comprising the following steps: - placing a molding out of one of more moldable clay into mold cavities of molding trays for taking out a device from the molding from clay as described above; - displacing the first part in the direction of the mold container in which the mold is received, which first part comprises at least one hollow punching member with open ends on both sides, wherein the punching member is pressed into the clay of the molding contained in the mold container; - moving the punching member out of the clay of the broth, wherein the punching member removes clay that has been punched out of the broth; - wherein the second part with retaining means restrains the clay of the green broth accommodated in the mold cavity of the mold container when the punching member is moved out of the clay; and - wherein the restraining means are covered with felt.

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In a preferred embodiment of the method, the punched-out clay is pushed through successive punching movements of the punching member through the hollow punching member until the open end remote from the mold container side leaves the punching member. New clay is punched out every subsequent punching movement. This pushes the clay already present in the punching member, which has been punched out during previous punching movements, further until it is pushed out of the punching member.

In a further preferred embodiment of the method, the clay leaving the punching member at the open end remote from the mold surface is collected on a collecting body.

In a still further preferred embodiment of the method, the clay collected on the collecting body is discharged through a discharge device.

In the following description, preferred embodiments of the present invention are further explained with reference to the drawing, in which:

Figure 1: a perspective view of a device 20 for manufacturing green bricks from the clay industry;

Figure 2: a perspective view of a device for punching recesses in green bricks;

Figure 3: a cross-sectional view of a part of the punching device shown in Figure 2;

Figure 4: a side view of the punching device shown in Figure 2;

Figure 5: a side view of a part of the punching device shown in Figure 4 in a first position; Figure 6: a side view of a part of the punching device shown in Figure 4 in a further position;

Figure 7: a side view of a part of the punching device shown in Figure 4 in a still further position; 10

Figure 8: a side view of a part of the punching device shown in Figure 4 in a still further position;

Figure 9 is a side view of a part of the punching device shown in Figure 4 in a still further position; Figure 10: a side view of a part of the punching device shown in Figure 4 in a still further position;

Figure 11: a cut-away perspective detail view of a mold container;

Figure 12A: a cross-sectional view of a felt retaining plate in a first embodiment; and

Figure 12B: a cross-sectional view of a retaining plate with felt in a second embodiment.

The device 1 for manufacturing green bricks for the brick industry comprises a chain conveyor 2, also referred to as molding tape. This chain conveyor 2 is composed of a large number of connected mold container parts 3 which in each case comprise a number of mold containers 16. Figures 1 and 2 show a so-called '16-bin mold belt', which means that the mold tray parts 3 are each provided with sixteen mold trays 16. Each mold tray 16 comprises a mold cavity 23 (Fig. 11) in which clay can be received around a molding 18 to shape. The mold container parts 3 are coupled to each other and are provided with rollers 15 that can be rotated over beams 14 so as to form together the chain - or belt - of the chain conveyor 2 - or mold belt. The chain is driven by one of the sprockets 13 or by both sprockets 13 (for clarity only the right-hand sprocket is shown in Figure 1). The conveying direction of the chain conveyor is counterclockwise in the illustrated embodiment of Figure 1 (P - in Figure 1). A conveyor turning clockwise is of course also possible.

Placed above the mold containers 16 is a clay reservoir 4 which is constantly kept in motion by a stirrer 5 which is driven by the motor 6. Clay 11 is supplied to the reservoir 4 by a circular conveyor 7. From the reservoir 4 the clay is supplied. introduced into the mold container 16 and subsequently pressed by a pressing device 8, which is pivotable about an axis 9. Also, by means of means (not shown), the excess of clay is wiped out.

The device 1 comprises a further conveyor 10 with which depositing plates 11 are supplied. The conveyor 10 also ensures that a depositing plate 11 is placed on top of each passing mold container part 3. The depositing plates 12 remain pressed against the respective mold container parts 3 by a retaining mechanism 12 as they pass through the left-hand sprocket (not shown) on the discharge side of the device. After turning the mold container part 3, the green bricks 18 still lie on the plates 11. An (not shown) pressing mechanism 15 presses the green bricks 18 from the mold trays 16 per mold container part 3. The green bricks 18 here remain on the plates 11 after they have been released from the mold containers 16. The plates 11 with the green bricks 18 thereon are then discharged for further treatment, such as drying and baking.

Figure 2 shows a perspective view of a punching device 19 for punching recesses 46 into bricks 18, which is arranged at the location of the frame shown in Figure 1.

The punching device 19 comprises a frame 24 which is adjustable in height direction H 25 and which comprises two parts 20, 22 which are movable relative to each other and which are connected to the frame 24 by means of beams 26. The first part 20 comprises a part 28 open at the top with a U-profile which is built up from a bottom plate 30 and upright walls 32. Furthermore, the first part 20 comprises a punching member 34 in the form of a hollow tube with both sides open ends. The second part 22 is connected to the first part 20 by means of bars 36 which act as a straight guide. A compression spring 38 is arranged around the bars 36 which pushes the 12 retaining plate 40 of the second part 22 away from the first part 20. In the retaining plate 40, openings 42 are provided through which the punching member connected to the first part 20 is movable. Furthermore, the retaining plate 40 is provided with a felt layer which reduces adhesion of the clay of the broth 18 to the retaining plate 40.

In Fig. 2 the direction of transport of the forming belt is indicated by arrow P1, with on the left-hand side in Fig. 2 greenings 18 being shown which have already been moved underneath the punching device 19 and are therefore provided with recesses 46.

In the punching device 2, each time a layer of clay is punched from a green brigade 18. This punched-out layer of clay is each time received as a part of clay 48 in the punching member 34. When the punching member 34 is filled from the mold container side with new clay, pieces of clay 48 already present in the punching member 34 are passed through the hollow punching member 34 with on both sides pushed open ends, as can be seen in figures 2 and 3.

The punching device 19 of Fig. 2 further comprises a discharge device 60 consisting of a shaft 62 on which sprockets 64 are arranged. The chain wheels 64 drive a conveyor 66 with plates 68 for discharging clay collected on the bottom plate 30 (Figure 2).

Figure 4 shows that the punching device 19 is driven by a crank mechanism 70 which comprises arms 72 which are adjustable in length. By varying the length of the arms 72, the starting position of the stroke of the punching device 19 can be adjusted. In this way, the punching device 19 can be adjusted to the desired stone thickness, such as, for example, 'Walloon format' or 'Thick format' stones, without having to adjust the length of the stroke. It is therefore not necessary to adjust the arm of the crank mechanism 70.

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With reference to figures 5-10, it will now be further explained how the punching device 19 functions. In Fig. 5, the punching device 19 is located above the mold container 16 in which a mold 18 is received.

When the punching device 19 is moved in the direction of the mold container 16 (indicated by the arrow), the retaining plate 40 with its felt layer 44 is pressed against the mold container 16 and the mold 18 received therein (Fig. 6).

When the punching device 19 is then further pushed downwards, the punching members 34 move through the openings 42 of the retaining plate 40 (Fig. 7). The punching members 34 are pushed into the clay of the blank 18 that is located in the mold cavity 23 of the mold container 16, the punching members 34 punching away a portion of the clay. The spring 38 is compressed when the second part 22 of the punching device 19 bears against the mold container 16 and the first part 20 of the punching device 19 is moved further down.

Then, when the first part 20 and the second part 22 of the punching device 19 move apart again (Fig. 8), the punching members 34 move out of the shaping 18. The clay 48 punched out by the punching members 34 is taken out along with the punching members 34 the green brigade 18, whereby recesses 46 are formed in the green brigade 18. By providing air supply openings 56 in the bottom part of the mold container 16, which is formed by the stamping member 54, 25, a vacuum is prevented when the clay 48 is pulled out of the mold 18 and prevents the clay from being taken out. It is noted that the air supply openings in figures 5-10 are only shown schematically as a channel, while in figure 11 they are shown as cross-forming.

When the punching members 34 are moved out of the green brigade 18, the spring 38 provides sufficient downward pressure in the direction 14 of the green container 16 on the retaining plate 40 that the clay of the green brigade 18 is retained.

When the punching members 34 have been completely removed from the blank 18, the distance between the second part 22 and the first part 20 of the punching device 19 is such that the spring 38 no longer presses the retaining plate 40 on the mold container 16 and together with the entire punching device 19 is moved away from the mold container 16 in the upward direction (Figure 10).

In the cut-away perspective view of a mold container 16 it can clearly be seen that a stamping member 54 forms the bottom of the mold cavity 23 of the mold container 16. In this bottom, air supply openings 56 are provided at the locations where the hollow punching members 34 will make the recesses 46 in the brigade 18, in order to prevent a vacuum from arising when the extracted clay 48 with the punching members 34 from the cavity 23 with the brigade 18 moves.

Figures 12A and 12B show two embodiments in which the felt 44 can be mounted on the retaining plate 40. In both embodiments, the felt extends at least locally through the retaining plate 40, so that it can be moistened from the top with supply means 50 for supplying a fluid 52, such as oil. The felt 44 wetted on the upper side of the retaining plate 40 will become soaked and so will also wet the felt 44 on the underside of the retaining plate 40, which reduces the sticking of clay.

The embodiments described above, although showing preferred embodiments of the invention, are only intended to illustrate the present invention and not to limit the description of the invention in any way. In particular, it is noted that the person skilled in the art can combine technical measures of the different embodiments. The scope of the invention is therefore solely determined by the following claims.

Claims (18)

An apparatus for manufacturing clay bricks for the brick industry, comprising: 5. a circular conveyor, which is joined from mold container parts, wherein each mold container part comprises one or more mold containers with a mold cavity in each case; - means for arranging deformable clay in the mold cavities of the mold containers; and 10. means for discharging green bricks discharged from the mold containers; - wherein the device further comprises two parts movable relative to each other; - the first part comprising at least one hollow punching member for providing a recess in the clay, the hollow punching member having open ends on both sides; - the second part comprising retaining means which are adapted to stop the broth when punching the clay from the broth; and - wherein the restraining means are covered with felt. 2. Device as claimed in claim 1, further comprising at least one spring 25 arranged between the first and second part which is adapted to press the retaining means against the mold container when the punching member is at least partially in the mold container. 3. Device as claimed in claim 1 or 2, further comprising: - a frame comprising two parts movable relative to each other; - wherein the frame is mountable above the mold container in which one or more green bricks are accommodated such that the frame with the movable parts is movable relative to the mold container, wherein the punching element arranged on the first part is at least partially displaceable in the mold container is for punching clay from a molding included in the mold container. Device as claimed in any of the foregoing claims, wherein the retaining means comprise a plate which is provided with at least one opening through which the punching member can be moved. 5. Device as claimed in any of the foregoing claims, wherein the device is further provided with supply means for supplying fluid to the felt. 6. Device as claimed in any of the foregoing claims, wherein the mold container is provided with at least one air supply opening. Device as claimed in any of the foregoing claims, wherein the punching member is hydraulically or pneumatically driven. 25 Device as claimed in any of the foregoing claims, wherein the hollow punching member is received at its end remote from the mold container side in a collecting body, on which clay passed through the hollow punching member can be collected. 30 Device as claimed in claim 8, wherein: - the collecting body is at least partially plate-shaped; and - the end of the hollow punching member remote from the mold container side is received in the plate-shaped collecting body; and - wherein furthermore a discharge device is provided for discharging clay collected thereon from the plate-shaped collecting body. 10. Device for taking clay out of a broth, comprising: 10. two parts movable relative to each other; - the first part comprising at least one hollow punching member for providing a recess in the clay, the hollow punching member having open ends on both sides; 15. the second part comprising restraining means which are adapted to stop the broth when punching the clay from the broth; and - wherein the restraining means are covered with felt. 11. Punching device as claimed in claim 10, wherein the two parts that are movable relative to each other are received in a frame that can be applied above a mold container in which one or more molds are accommodated. 12. Punching device as claimed in claim 11, wherein the mold container is part of a device for manufacturing green bricks for the brick industry. 13. Punching device according to one of claims 10-12, 30 for use in a device according to one of claims 1-9. 8 14. Method for punching clay from a broth, comprising the steps of: - placing bricks formed from one of more malleable clay in mold cavities of mold containers, a device for taking clay out of the broth according to one of the claims 10-13; - moving the first part in the direction of the mold container in which the green bristle is accommodated, which first part comprises at least one hollow punching member with open ends on both sides, wherein the punching member is pressed into the clay of the green broth accommodated in the molding container; - moving the punching member out of the clay of the broth, wherein the punching member removes clay that has been punched out of the broth; 15. wherein the second part with restraining means restrains the clay of the green broth received in the mold cavity of the mold container when the punching member is moved out of the clay; and - wherein the restraining means are covered with felt. Method according to claim 14, wherein the punched-out clay is pushed through successive punching movements of the punching member through the hollow punching member until the open end remote from the mold container leaves the punching member. 25 A method according to claim 15, wherein the clay leaving the punching member at the open end remote from the mold container is collected on a collecting body. 17. Method as claimed in claim 16, wherein the clay collected on the collecting body is discharged by a discharge device. A method according to any of claims 14-17, wherein a device according to any of claims 1-13 is used.