EP1536933B1 - Moulding insert for moulding machines - Google Patents

Abstract

The invention relates to the production of multi-layered concrete moulded bodies in a moulding machine comprising a moulding insert having a plurality of mould cavities. Relief structures are arranged in the lateral walls of the mould cavities and are dimensioned in such a way that projections formed on the moulded body when the filled concrete material is compacted engage in the relief structures, thereby creating sufficient retaining force for compensating the net weight of the moulded body and enabling the moulded bodied to be extracted from the mould cavities as a result of additional demoulding forces and causing elastic deformation of the projections without any material being cut off from the projections.

Description

The invention relates to a mold insert for molding machines for the production of compacted moldings.

Such mold inserts are especially in use devices for the production of concrete blocks and form together with a mold frame a vibrating mold. The mold cavities of the mold insert placed on a vibrating table are filled with concrete mass and closed at the top by pressure stamps. By vibrating the vibrating table, the concrete mass is compacted so much that the subsequently removed from the mold insert damp conglomerates remain dimensionally stable and can be stored for final drying and curing.

1. a) Einlagenfertigern, welche die Formsteine auf einer auch beim Rüttelvorgang zwischen Rütteltisch und Formeinsatz befindlichen Zwischenplatten belassen, beim Entformen den Formeinsatz von der Zwischenplatte abheben und die eine Lage von Formsteinen samt der Zwischenplatte zur Zwischenlagerung verwenden, wobei typischerweise mehrere Einheiten mit je einer Platte und einer Lage Formsteine aufeinander gestapelt sind.
2. b) Mehrlagenfertigern, bei welchen mehrere Lagen von Formsteinen ohne Zwischenplatten aufeinander abgelegt werden. Hierzu müssen die Formsteine in den Formnestern auch nach Abheben des Formeinsatzes von dem Rütteltisch oder gegebenenfalls von einer Zwischenplatte in den Formnestern gehalten und zur Ablage aus den Formnestern ausgedrückt werden.

For such intermediate storage a distinction is made between

1. a) insert finishers, which leave the bricks on a between the vibrating and forming insert between the intermediate plates, during demoulding the mold insert from the intermediate plate and use a layer of molded bricks together with the intermediate plate for intermediate storage, typically several units, each with a plate and a layer of shaped stones are stacked on top of each other.
2. b) multi-layer finishers, in which several layers of molded bricks are placed on each other without intermediate plates. For this purpose, the stones in the mold cavities even after lifting the mold insert of the vibrating table or optionally of an intermediate plate in held the mold cavities and expressed for storage from the mold cavities.

An apparatus for the production of concrete blocks in multi-layer production (multi-layer production), for example, in US-A-4 545 754 described where it is stated that in the intermediate step in which the mold insert is lifted with the compacted molded bricks from the Rüttelunterlage, the bricks are held solely by friction and adhesion to the side walls of the mold cavity.

A mold insert for use in molding machines for the production of concrete blocks, according to the preamble of claim 1 is made DE-U-296 11484 known.

The invention has for its object to provide an advantageous mold insert for multi-layer production.

The invention is described in claim 1. The dependent claims contain advantageous refinements and developments of the invention.

In the mold insert according to the invention, on the one hand, the compacted bodies are intended to be inherently dimensionally stable in accordance with the objective of compaction and therefore in the mold insert counteracting the self-balancing force (as well as acceleration or inertial forces possibly occurring during a movement of the mold insert with the compacted moldings) can be held positively. On the other hand, the z. B. from the DE-A-44 43 475 or the DE-A-197 47 770 known property of compacted concrete moldings to be still elastic in the wet state, made advantageous use. Both properties known per se are advantageously combined in such a way that the positive engagement between recesses in the relief structure in the walls of the mold cavity and protrusions produced in these depressions on compartments of lateral surfaces of the molded body is dimensioned so large that, on the one hand, a (consisting of volume and Material resulting) own weight of the molding excess force is required down to the molding of the molding, which is applied by a vertical movement of the mold insert relative to the compression device also used for compacting in a simple manner, but on the other hand, the positive engagement is limited so that the in the recesses of the relief structure engaging projections on the side walls of the shaped body are not sheared in the forced removal and / or that there are no residues left in the relief structure substantially above the normal level of conventional mold inserts having flat walls. The relief structure also allows in particular the use of mold inserts with hardened walls with very little material adhesion to the concrete mass of the molding.

The relief has as support surfaces on which are supported projections of the side surfaces of the compacted molded body, holding flanks, which are inclined obliquely to the interior of the mold cavity down. The angle of these holding surfaces against the vertical is preferably at most 30 °, so that in the forced removal of a sliding of the projections along the retaining flanks with gradual lateral deformation of the material of the shaped body, preferably within the range of elastic deformation takes place. A small permanent deformation of the projections on the side surfaces of the shaped body is not critical, since the function of these projections to keep the shaped body against its weight in the mold insert, omitted after the molding.

The weight of the molded article depends not only on the volume but also on the density of the material, which typically does not vary significantly, so that the weight of the compacted molded article can be considered substantially known. When estimating the required holding force, it must additionally be taken into account that in the case of multi-layer finishers, the mold insert with the compacted moldings is typically moved vertically and possibly also horizontally after compression and acceleration forces occur here which may not yet cause the moldings to fall out of the mold insert. With regard to the deformability of the wet molded article after compression, depending on the extent of the compression, higher scattering may result, which may affect the holding force and the maximum elastic deformability. advantageously, Therefore, the depth of the relief structure can be designed for high rigidity with low elastic deformability and the entire holding surface of all retaining flanks for low rigidity with easy deformability of the compacted wet molded body in the context of expected scattering.

Advantageous for the relief depth of the relief structure proves to be a depth of a maximum of 1.5 mm, in particular of a maximum of 0.8 mm. The minimum depth is advantageously 0.2 mm. In order to obtain a sufficient holding force on the sum of the holding surfaces of all holding flanks, the cumulative Erstrekkung all holding flanks in wall-parallel horizontal direction is at least equal to the circumference of the shaped body, preferably at least equal to twice this circumference. The relief structure can advantageously have successively multiple retaining flanks in the vertical direction which are separated by sections of the relief structure which do not apply holding forces.

In an advantageous embodiment, the relief structure contains concave and / or convex curvatures with a radius of curvature that is large, preferably at least 5 times that of the relief depth. Concave and / or convex curvatures can form a wave-like profile immediately following each other.

The relief structure may advantageously comprise elongated, preferably substantially horizontal grooves, in particular with a constant cross section. For polygonal floor plans, such grooves advantageously extend over more than half the distance between two adjacent corners. The retaining flanks of the relief structure are preferably present at opposite with respect to the volume of gravity of the mold cavity wall surfaces and / or in rotationally symmetrical arrangement about a vertical center axis of the mold cavity.

The terms of the depressions in the relief structure and projections on the side walls are in principle also used in permutation, but relate vividly to a preferred embodiment in which the mold cavity, preferably in the upper edge region, has at least one prismatic section with vertical wall surfaces without relief structure and the relief structure recedes behind the continuation surfaces of this prismatic section.

The relief structure is advantageously predominantly, in particular formed to at least 60% in the lower half of the vertical extent of the mold cavity. According to a development, it can be provided that the clear cross section of the mold cavity widens downwards in the course of the relief structure.

Fig. 1

eine Schrägansicht von oben in einen Formeinsatz,

Fig. 2

einen mit dem Formeinsatz nach Fig. 1 hergestellten Formstein,

Fig. 3

ein Schnittbild entlang A - A von Fig. 1,

Fig. 4

einen vergrößerten Ausschnitt aus Fig. 3,

Fig. 5

einen Ausschnitt entsprechend Fig. 4 mit alternativer Reliefform,

Fig. 6

eine Ansicht entsprechend Fig. 3 mit erhabenem Relief.

The invention is illustrated below with reference to preferred embodiments with reference to the figures still in detail. Showing:

Fig. 1

an oblique view from above into a mold insert,

Fig. 2

a molded block produced with the mold insert according to FIG. 1,

Fig. 3

a sectional view along A - A of Fig. 1,

Fig. 4

an enlarged detail of Fig. 3,

Fig. 5

a section corresponding to FIG. 4 with an alternative relief shape,

Fig. 6

a view corresponding to FIG. 3 with raised relief.

In Fig. 1, a mold insert or a section of such a mold insert FE is sketched with a plurality of mold cavities FN with a view from obliquely above into the mold cavities. The mold cavities are in the example sketched approximately rectangular and bounded by side or partition walls WS. The mold cavities are open at the top for filling non-compacted concrete mass and for inserting pressure plates tightly closed with the contour of the mold cavities, which are loaded by a load or otherwise pressed down into the mold cavities. The mold insert is placed in operation on a vibrating table, optionally with the interposition of an intermediate plate and pressed by means of a not shown in the figure with the mold frame down. The vibrating table is stimulated by shock vibration or vibration vibration vibrating vibrations, which are transmitted to the filled concrete material and under the action of stress by the pressure device, the concrete material in a short time so high density that the resulting molded blocks are still moist, but dimensionally stable.

In multi-layer production, the mold insert is placed on a tray, for example a pallet as a first layer or on existing layers after completion of the compaction process while maintaining the relative position of mold insert and printing device. Here, either the pallet instead of the vibrating table under the mold insert or the mold insert including printing plates can be moved sideways over the pallet. By lifting the mold insert the blocks are expressed by the not raised with printing plates of the printing device down from the mold cavities and stored on the shelf or an existing layer of molded bricks for drying and curing.

In the mold insert sketched in FIG. 1, it can be seen that the wall surfaces of the walls WS delimiting the mold cavities are provided with relief structures RS, which in the example shown are found both on wall surfaces NWL extending in the longitudinal direction LR and on wall surfaces NWQ extending in the transverse direction QR. The relief structures have in the preferred embodiment outlined in the form of elongated horizontally extending grooves, which, possibly with interruption, claim the majority of the wall surface in the horizontal direction. In the vertical direction, several such horizontal grooves follow each other. The relief structures RS extend in the example sketched over more than half the height of the side wall surfaces. In the side wall surfaces wells AA are provided to form spacers on the side surfaces of molded bricks.

FIG. 2 shows an oblique view of a concrete block produced in a mold cavity FN of the mold insert FE according to FIG. 1, on the side surfaces of which both spacers AH and counter-relief structures GR are complementary structures to the relief structures RS and the recesses AA in the wall surfaces NWL, NWQ of FIG Formnestes have arisen. The edges at the transition from the side wall surfaces to the top surface of the concrete block of FIG. 2 are chamfered by known shaping of the used printing plates.

In FIG. 3, a horizontal view is partially sketched into a mold cavity cut open along a vertical sectional plane along A - A of FIG. 1. The relief structure RS is located predominantly in the lower half of the edge surface NWL and takes in the example sketched more than half the height of the wall surface. In the horizontal direction, the relief structure is interrupted by a recess AA for a spacer. The two substructures each have the length RL, wherein the total longitudinal extent of the relief structure with 2RL is preferably greater than half the longitudinal extent NL of the mold cavity. A pressure plate DP z. B. loaded with a load pressure device is placed after filling the mold cavity on this.

The relief structures consist of horizontal grooves NU, which, as can be seen more clearly from the enlarged detail in FIG. 4, are curved concavely away from the interior of the mold cavity. The grooves have in the example sketched a uniform curvature with a radius of curvature, which is large against the relief depth RT of the relief structure. A compacted molded block body produced in the mold cavity is positively connected to the relief structures with its side surfaces and thus kept in the mold cavity even after removal of the supporting vibrating table, wherein the holding forces absorbing the weight force are applied to holding surfaces HF which pass through the respective lower regions of the individual grooves are formed with down to the mold cavity extending surface tangents, whereas partial surfaces of the relief structure with vertical or with downwardly directed away from the mold cavity surface tangent not contribute to the holding forces. The entire holding force which becomes effective for a shaped body in a mold cavity is composed of the sum of the partial forces applied to all these holding surfaces HF. Due to the long extent in the horizontal direction and the multiple succession in the vertical direction of the grooves of the relief structures results even at low relief depth RT a weight of the molding body compensating holding force.

The holding force applied by the holding surfaces HF is limited by the fact that the molded body is still elastically deformable even after compression and along the holding surfaces HF under lateral compression down can be moved. However, the relief structures are dimensioned so that only the weight of the molded body is not sufficient to deform the molded body so far that the protruding in the relief structures projections of the molded body overcome the relief along the support surfaces down. On the other hand, the relief structures are dimensioned so that a deformation of the shaped body is possible by using a force higher than its own weight in at least the extent without shearing the engaging into the relief structures protrusions of the molded body, that these projections overcome the relief structures down and the molding can be expressed in the mold cavity.

The relief depth RT is advantageously at most 1.5 mm, preferably at most 0.8 mm, in particular at most 0.5 mm. The minimum depth RT of the relief structures is advantageously 0.1 mm, preferably 0.2 mm, in particular 0.3 mm. In the example outlined, a uniform relief depth is assumed for all grooves, which is preferred but not mandatory.

5, an embodiment of a relief structure is sketched, in which the relief structure shows convex curvatures NX towards the interior of the mold cavity. The mode of action is analogous to the relief structure according to FIG. 4.

In the illustrations according to FIGS. 1 and 3, the mold cavity has a prismatic profile in an upper region with unstructured vertical wall surfaces and a cross-section which remains constant in the vertical direction. In FIG. 3, the relief structure RS in the wall surface NWR is set back against the vertical extension of this prismatic section AP, whereby the corresponding prismatic upper section of the shaped body does not undergo any deformation through the relief when it is molded downward. In another embodiment, as outlined in Fig. 6, the relief structure RSX against the vertical extension of the prism surfaces of the section AP to be raised to the interior of the mold cavity. In the version according to FIG. 6, it should be noted that the printing plate, which typically has a gap of approximately 0.5 mm to the wall of the mold cavity, can be moved past the relief structure if necessary for molding.

The depth of the recesses AA for the formation of spacer elements on the side walls of the molding is typically substantially greater than the relief depth RT. These recesses are open at the bottom, so that the spacing element AH formed on the shaped body undergoes no compressive deformation when the shaped body is shaped out of the mold cavity.

The relief structures recognizable in FIG. 1 only on one longitudinal and one transverse surface of the mold cavity are advantageously formed at least on two opposite wall surfaces or preferably on all wall surfaces. The holding forces can thereby occur uniformly on the one hand and be distributed on the other to a plurality of holding surfaces with low relief depth.

The invention is not limited to the described embodiments. In particular, a variety of possibilities from combinations of the described shapes or other, non-linear substructures are possible for the shape of the relief structure. The substructures can also be smaller and / or more spatially separated.

Claims (12)

1. Mould insert (FE) with one or more mould nests (FN) for insertion in moulding machines for the production of concrete blocks as compacted mouldings (FS) and for depositing them in a multi-layer arrangement, the apparatus containing pressure devices for pushing the compacted mouldings out of the mould insert downwards, and there being provided on the walls of the mould nest retention means which ensure that the compacted moulding is held in the mould nest until it is pushed out, characterized in that the walls of the mould nest have as retention means relief structures with depressions which possess holding flanks (HF) descending downwards towards the middle of the mould nest, the relief (RS) being co-ordinated with the volume of the mould nest and with the material of the moulding such that, on the one hand, the dead weight of the moulding is not sufficient to remove the latter from the mould nest and, on the other hand, the moulding can be removed from the mould nest under the influence of the pressure devices, without the shearing off of the projections (GR) on side faces of the moulding which penetrate into depressions of the relief.
2. Mould insert according to Claim 1, characterized in that the relief depth (RT) of the relief structures (RS) is less than 1.5 mm, preferably less than 0.8 mm.
3. Mould insert according to Claim 1 or 2, characterized in that the holding flanks (HF) are strip-shaped and run at least predominantly horizontally.
4. Mould insert according to one of Claims 1 to 3, characterized in that holding flanks are multiply arranged in succession in a vertical direction.
5. Mould insert according to one of Claims 1 to 4, characterized in that the cumulative length of the holding flanks (HF) is greater than the circumference of a moulding (FS) capable of being produced in the mould nest (FN), preferably greater than twice the circumference of the moulding.
6. Mould insert according to one of Claims 1 to 5, characterized in that holding flanks are formed on at least two wall faces of the mould nest which lie opposite one another with respect to the centre of gravity of the moulding.
7. Mould insert according to one of Claims 1 to 6, characterized in that the relief structure contains grooves (NU, NX) of concavely and/or convexly curved cross section.
8. Mould insert according to one of Claims 1 to 7, characterized in that the wall of the mould nest contains a prismatic wall portion, and the relief (RS) is set back relative to the wall faces of the prismatic portion.
9. Mould insert according to one of Claims 1 to 8, characterized in that the relief is formed predominantly in the lower half of the vertical extent of the walls of the mould nest.
10. Mould insert according to one of Claims 1 to 9, characterized in that the clear cross section of the mould nest widens downwards along the vertical run of the relief structure.
11. Mould insert according to one of Claims 1 to 10, characterized in that, in the walls of the mould nest, additional depressions (AA) are introduced for spacer elements (AH) which are to be integrally formed on the moulding and which have a greater depth than the relief structure and are open downwards.
12. Mould insert according to one of Claims 1 to 11, characterized in that the surfaces of the walls (NWL, NWQ) of the mould nests are hardened.

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