Apparatus for producing soft-mud bricks and filling chamber for clay in such an apparatus

Abstract

 The apparatus (1) comprises a plane mould table with a number of mould cavities extending through the mould table, which mould table is reciprocally displaceable in its plane by means of means (13), a filling chamber (4) for clay above the mould table at a filling position for the mould cavities, an abutment for the mould table below the latter at the filling position, which abutment closes the mould cavities downwardly in the filling position, a pressing-out device (6) above the mould table at a pressing-out position for the mould cavities, and a conveyor (7) below the mould table at said pressing-out position, the mould table containing at least two parallel rows of mould cavities, a pressing-out position being provided with a pressing-out device (6) and conveyor (7) on each side of the filling position, whereby each row of mould cavities has its own pressing-out position, and whereby one row of mould cavities is in its pressing-out position while another row is in its filling position, the filling chamber (4) being longitudinal to cover the entire row of mould cavities in the filling position.

Description

[0001] The present invention relates to an apparatus for the manufacture of soft-mud bricks, comprising a plane mould table with a number of mould cavities extending through the mould table, which mould table is reciprocally displaceable in its plane, a filling chamber for clay above the mould table at a filling position for the mould cavities, an abutment for the mould table below the latter at the filling position, which abutment closes the mould cavities downwardly, a pressing-out device above the mould table at a pressing-out position for the mould cavities, and a conveyor below the mould table at said pressing-out position.

[0002] The manufacture of bricks of the above type is made with clay having a high water content, and the clay therefore has a very soft consistency during moulding of the clay into clay lumps shaped like bricks. When the clay lumps have been shaped into bricks, they can thus keep their shape when they are placed on their long, narrow surface, whereas they cannot be handled manually as the clay does not have sufficient strength to withstand the pressure from the fingers.

[0003] Bricks with a structure and surface like those of handmade bricks are in high demand. This is why it is desired to be able to manufacture such bricks in automated plants so that the bricks can be manufactured at an advantageous price.

[0004] In a known apparatus of the type mentioned in the introduction, the mould table contains one or two mould cavities and can be displaced from a filling position to a pressing-out position by horizontal reciprocal displacement to one side of the filling chamber where a pressing-out mechanism has been arranged. However, this known apparatus has a relatively limited capacity and is designed for special jobs, not for large-scale production of standard bricks. The mould cavities are placed within a small area, and the filling chamber uses two counter-rotating vertical screws for pressing the clay down towards the mould cavities in the filling position.

[0005] Another apparatus is known in which the mould table is a carrousel that turns continuously from a filling section to a pressing-out mechanism and onwards for renewed filling. This apparatus has a larger capacity, but one disadvantage is that the pressing-out mechanism must be synchronised with the turning mould table and accompany it during the pressing-out, which complicates the design and also reduces the manufacturing rate. Also in this apparatus, the filling position is concentrated within a small area, and the filling chamber applies a single vertical rotor with inclined projecting plates, which screw the clay down towards the mould table in the filling position.

[0006] Other known apparatuses include, for example, apparatuses from the firm De-Boer, where a basic module of mould boxes with a number of mould cavities is fastened to an endless conveyor chain. Above the chain a filling system is arranged for filling clay into the moulds, which have a movable bottom used for pressing the moulded bricks out of the mould. The filling system may consist of a container with clay, which is pressed down through the container and out through nozzles by several parallel, vertical rotors and cut into suitable lumps. These apparatuses often use sprinkling with dry sand to facilitate emptying of the moulds and ensure that the bricks do not stick to conveyors, etc. The resulting bricks are therefore sand-faced, which is not to the taste of the consumers in the Nordic countries, among others.

[0007] Further, EP 0 523 286 A1 describes an apparatus for the manufacture of ceramic tiles by high-pressure pressing. The apparatus comprises a press with a vertically movable cross-member carrying on its lower surface the upper part of a mould tool, and two carriages arranged on opposite sides of the cross-member and provided with identical lower mould parts, which carriages are moved alternately towards a pressing position from respective emptying positions located symmetrically about the pressing position. The lower mould parts are filled by means of filling hoppers arranged on both sides of the press and provided with valve means so that the lower mould parts are filled while the carriages move from the respective emptying positions to the pressing position.

[0008] As mentioned, this is an apparatus for the manufacture of ceramic tiles by high-pressure pressing, and the apparatus is unsuitable for the manufacture of soft-mud bricks. This is due to the fact, among others, that the mould cavities do not extend through the mould, since soft-mud bricks will be practically impossible to remove from the mould as these bricks have a very soft consistency, as mentioned above.

[0009] The object of the invention is to provide a highcapacity apparatus that can manufacture soft-mud bricks similar to hand-made bricks in terms of both appearance and physical properties, and a filling chamber suitable for use in such an apparatus.

[0010] The apparatus according to the invention is characterized in that the mould table contains at least two parallel rows of mould cavities, that there is a pressing-out position with a pressing-out device and conveyor on each side of the filling position, whereby each row of mould cavities has its own pressing-out position, and whereby one row of mould cavities is in its pressing-out position while another row is in its filling position, and that the filling chamber is longitudinal to cover the entire row of mould cavities in the filling position.

[0011] An apparatus according to the invention allows simultaneous filling and emptying of moulds, as, when the mould table is displaced to one side to the pressing-out or emptying position for one row of moulds, it has at the same time conducted another row of moulds to the filling position below the filling chamber. This provides an advantageous continuous work process for the apparatus and provides for high capacity.

[0012] According to a preferred embodiment, the apparatus is characterized in that, as distribution means, the filling chamber has a roller driven to rotate and extending in parallel with the mould cavity rows. This ensures even distribution of clay in the filling chamber over the entire length of the mould cavity rows.

[0013] According to a particularly preferred embodiment, the apparatus is characterized in that the distribution means comprises two rollers extending in parallel beside each other with a roller nip between them, which two rollers are driven in mutually opposite directions of rotation. Two rollers of this type ensure to an even higher degree than just one roller that the clay in the filling chamber is evenly distributed over the entire length of the mould cavity rows.

[0014] Furthermore, according to a preferred embodiment, an apparatus with or without distribution means as mentioned above is characterized in having reciprocating movable pressing means for pressing the clay down towards the mould cavities in the filling position. Such pressing means ensures that the mould cavities are rapidly filled with a suitable amount of clay.

[0015] According to a particularly preferred embodiment, the apparatus is characterized in that the pressing means is constituted by the roller or rollers, which are movable upwards and downwards. The roller or rollers may thus have the double function of both distribution means and pressing means, which reduces the number of parts for the apparatus in an advantageous manner.

[0016] If necessary or desired, the apparatus may be characterized in having two parallel pairs of rotating rollers, one pair arranged above the other, the upper pair being stationary and the lower pair being movable upwards and downwards.

[0017] According to another embodiment, the apparatus is characterized in that the pressing means comprises swingable members with a pressing surface facing the mould cavities in their filling position.

[0018] The invention also relates to a filling chamber in an apparatus for the manufacture of soft-mud bricks, which apparatus has a row of mould cavities.

[0019] The filling chamber according to the invention is characterized in having distribution means in the filling chamber, comprising a roller driven to rotate and extending in parallel with the mould cavity row, which roller is furthermore movable upwards and downwards for pressing the clay down towards the mould cavities.

[0020] This design provides a particularly simple design of the filling chamber as the roller acts both as a distribution means and pressing means for dispensing clay.

[0021] The invention will now be described in further detail below with reference to the drawing, in which

Fig. 1 is a top view of a mould table,

Fig. 2 is a side view of an apparatus according to the invention with movable rollers

Fig. 3 is a partial end view of the apparatus according to Fig. 2,

Fig. 4 is a partial cross-sectional view of the apparatus according to Fig. 2,

Fig. 5 is a longitudinal cross-sectional view of part of the apparatus according to Fig. 2,

Fig. 6 is a side view corresponding to that of Fig. 2, but of an apparatus of an alternative design with swingable members instead of movable rollers,

Fig. 7 is an end view of the apparatus according to Fig. 6,

Fig. 8 is a partial cross-sectional view of the apparatus according to Fig. 6, and

Fig. 9 is a cross-sectional view of a smoothingscraping arrangement.

[0022] The apparatus according to the invention for the manufacture of soft-mud bricks is generally designated 1. The apparatus 1 comprises a mould table 2, which is a rectangular plate with two, possibly double or multiple rows of through-going, preferably rectangular mould cavities 3. The entire mould table 2 is displaceable in the transverse direction, for example by means of a hydraulic cylinder 13, which can displace the mould table 2 in its plane. The mould table 2 thus has two end positions, in which one and the other row of mould cavities 3, respectively, has a filling position where the row of mould cavities 3 is located directly below a filling chamber 4 for filling of the mould cavities 3 with clay, and a pressing-out position where the row is displaced a maximum distance from the filling position so that the mould cavities 3 are each in a pressing-out position below a pressing-out mechanism 6.

[0023] Above the mould table 2 a filling chamber 4 for clay is arranged, which chamber extends over the entire length of a row of mould cavities 3. The filling chamber 4 receives clay from a store through a conveyor 14 connected to a flange 14' at the top of the filling chamber 4, and the filling chamber 4 is provided with means for distributing the clay and for filling mould cavities 3 in the mould table 2, which forms the bottom of the filling chamber 4 when these mould cavities 3 are in the filling position.

[0024] Under the mould table 2, at the filling position below the filling chamber 4, an abutment 5 is arranged for forming the bottom of the mould cavities 3 during the filling. According to a preferred embodiment, the abutment 5 is provided with small through holes opposite to the mould cavities 3 in the filling position to permit drainage of surplus water from the clay in the mould cavities 3. Means may suitably also be provided for displacement and pressing of the abutment 5 up against the mould table 2 during filling of the mould cavities 3, and displacement away from the mould table 2 to facilitate the sideways removal of the mould table 2.

[0025] At the pressing-out positions, pressing-out means 6 (see Fig. 6) is provided, which means comprises pressing shoes 16 actuated, for example, by means of a hydraulic cylinder 17, but of course other forms of actuation may be used, for example pneumatic actuation or actuation by means of an electromagnetic or mechanical actuator. According to a preferred embodiment, the pressing-out means 6 is hinged at the top and controlled as illustrated in Fig. 3, so that the pressing-out means 6 is adjusted according to the current position of the mould table, the pressing-out means 6 being connected with an adjustable end stop 6' which the mould table 2 hits at its maximum sideways displacement to the pressing-out position. The pressing-out means 6 is pulled by a spring 6a towards an adjustable resting abutment 6b, which defines a resting position. The pressing surface itself can suitably be constituted by a replaceable plate of a wear-resistant material, which plate has an extent corresponding to, but slightly smaller than the mould cavity 3. Alternatively, the pressing-out means may be firmly mounted, as shown in Figs. 7 and 8, without the possibility of sideways movement.

[0026] After being pressed out, the lumps of clay provided by the pressing out and shaped like the mould cavities 3 are transported away on a conveyor 7 and on to a star wheel 18, where they are raised on to a side surface before they are transported onwards for further processing, including firing. This transport and further processing take place in a manner known per se.

[0027] The filling chamber 4 for clay extends over the entire length of a row of mould cavities 3, and in the examples shown, distribution means is provided in the filling chamber 4, the distribution means being constituted by two rollers 8 driven to rotate in opposite directions and extending in parallel with the mould cavity rows 3. The rollers are driven by hydraulic engines or electromotors 21 by direct shaft connection at the ends of the rollers. In the embodiment shown in Figs. 2-5, the rollers 8 are movable upwards and downwards so that in addition to being distribution means they can act as pressing means by downward movement for filling of the mould cavities 3 in their filling position. The movement in a direction at right angles to the rotational axis of the roller or rollers can be obtained as shown in Fig. 5 by the rollers 8 being journalled in panels 31, which slide in guideways 32 at the ends of the filling chamber so that the rollers 8 can be moved transversely to the rotational axis by means of actuating means, such as hydraulic cylinders 20, an electromotor or any other suitable actuating means.

[0028] The conveyor connected with the filling chamber 4 may comprise a pugging means 22, for example in the form of two worms that can provide some of the pressure in the filling chamber 4.

[0029] According to an alternative embodiment of the pressing means, seen in Fig. 8, this pressing means may comprise members 9 swingable between two positions a,b and having a pressing surface 10 facing the mould cavities in their filling position. In the example, the swingable members 9 are provided with an inclined, preferably roof ridge-shaped sliding-off surface 11 on their surface opposite to the pressing surface 10. With such a sliding-off surface 11, the return movement of the swingable members 9 against the clay in the filling chamber 4 will be substantially easier. The swinging movement may be actuated by a hydraulic cylinder 23, which, via an arm 24, turns a shaft 25 on which the swingable members 9 are mounted.

[0030] Right up against the filling chamber 4, at the upper side of the mould table on both sides of the filling chamber 4, a scraping-smoothing arrangement 26 may be provided for scraping away surplus clay mass so that the clay in the mould cavities gets an even and smooth surface. The scraping-smoothing arrangement 26 comprises a row of inclined smoothing shoes 27, and a scraper 28 on either side. The scraping-smoothing arrangement 26 may also be provided with a water supply so that water is supplied between the smoothing shoes 27 towards the upper surface of the mould table 2.

[0031] As outlined in Fig. 8, the abutment 5 for the mould table 2 at the filling position for the mould cavities 3 may comprise part areas 29 that, connected with longitudinal rods 30, can be raised above the plane of the abutment and lowered to flush with this plane, means, not shown, also being provided for controlled raising and lowering of the rods 30 and thus the part areas 29 so that they are raised during the filling of the mould cavities 3 and lowered during the displacement of the mould table. This allows the manufacture of bricks with a depression, a so-called mortar pocket, which saves upwards of 10-15 per cent of the clay and thus also provides bricks with a correspondingly lower mass.

[0032] The work cycle of the apparatus is as follows: clay from a store is supplied to the filling chamber 4 by means of the conveyor 14. Under the filling chamber 4, the mould table 2 is displaced alternately to either side of the filling chamber 4. When a row of mould cavities 3 is located in the filling position below the filling chamber 4, rollers 8 are moved towards the mould cavities 3, thus building up a larger pressure in the clay mass between the rollers 8 and the mould cavities 3, and the mould cavities 3 are filled with clay, the abutment 5 arranged below the mould table 2 forming the bottom of the mould cavities 3 in the filling position. When the row of mould cavities 3 is filled, the abutment 5 and any part areas 29 are lowered, and the mould table 2 is displaced sideways away from the filling chamber 4 and the underlying abutment 5, so that the row of filled mould cavities 3 reaches its pressing-out position, where there is no bottom under the mould cavities 3, while the other row of empty mould cavities 3 reaches the filling position below the filling chamber 4. In the pressing-out position, the shaped clay mass is pressed out by the pressing-out means 6 on to the conveyor 7, which transports the lumps of clay to the star wheel 18 as described above. At the same time, the abutment 5 and any part areas below the other row of mould cavities 3 are raised, whereupon the abovementioned work cycle is repeated.

Claims

1. An apparatus (1) for the manufacture of soft-mud bricks, comprising a plane mould table (2) with a number of mould cavities (3) extending through the mould table (2), which mould table (2) is reciprocally displaceable in its plane, a filling chamber (4) for clay above the mould table (2) at a filling position for the mould cavities (3), an abutment (5) for the mould table (2) below the latter at the filling position, which abutment (5) closes the mould cavities (3) downwardly in the filling position, a pressing-out device (6) above the mould table (2) at a pressing-out position for the mould cavities (3), and a conveyor (7) below the mould table (2) at said pressing-out position characterized in that the mould table (2) contains at least two parallel rows of mould cavities (3), that there is a pressing-out position with a pressing-out device (6) and conveyor (7) on each side of the filling position, whereby each row of mould cavities (3) has its own pressing-out position, and whereby one row of mould cavities (3) is in its pressing-out position while another row is in its filling position, and that the filling chamber (4) is elongated to cover the entire row of mould cavities (3) in the filling position.

2. An apparatus according to claim 1, characterized in that, as distribution means, the filling chamber has a roller (8) driven to rotate and extending in parallel with the mould cavity rows (3).

3. An apparatus according to claim 2, characterized in that the distribution means comprises two rollers (8) extending in parallel beside each other with a roller nip between them, which two rollers (8) are driven in mutually opposite directions of rotation.

4. An apparatus according to claims 1-3, characterized in having reciprocating movable pressing means for pressing the clay down towards the mould cavities (3) in the filling position.

5. An apparatus according to claim 2 or 3 in combination with claim 4, characterized in that the pressing means is constituted by the roller (8) or rollers (8), which are movable upwards and downwards.

6. An apparatus according to claim 5, characterized in having two parallel pairs of rotating rollers, one pair arranged above the other, the upper pair being stationary and the lower pair being movable upwards and downwards.

7. An apparatus according to claim 4, characterized in that the pressing means comprises swingable members (9) with a pressing surface (10) facing the mould cavities (3) in their filling position.

8. An apparatus according to claim 7, characterized in that the swingable members (9) are provided with an inclined, preferably roof ridge-shaped sliding-off surface (11) on their surface opposite to the pressing surface (10).

9. An apparatus according to claims 1-8, characterized in that the abutment (5) for the mould table (2) at the filling position for the mould cavities (3) comprises part areas that can be raised above the plane of the abutment and lowered to flush with this plane, means being provided for controlled raising and lowering of these part areas so that they are raised during the filling of the mould cavities (3) and lowered during the displacement of the mould table (2).

10. An apparatus according to claims 1-9, characterized in that a row of mould cavities is constituted by a group comprising two or more part rows of mould cavities.

11. A filling chamber for clay in an apparatus for the manufacture of soft-mud bricks with a row of mould cavities (3), characterized in having distribution means in the filling chamber (4), comprising a roller (8) driven to rotate and extending in parallel with the mould cavity row (3), which roller (8) is furthermore movable upwards and downwards for pressing the clay down towards the mould cavities.

12. A filling chamber according to claim 11 characterized in that the distribution means comprises two rollers (8) extending in parallel beside each other with a roller nip between them, which two rollers (8) are driven in mutually opposite directions of rotation, and both are movable upwards and downwards.

13. A filling chamber according to claim 12, characterized in having two parallel pairs of rotating rollers, one pair arranged above the other, the upper pair being stationary and the lower pair being movable upwards and downwards.

Drawing