FI76513C - GLIDGJUTMASKIN FOER FRAMSTAELLNING AV BETONGELEMENT. - Google Patents

Description

7651 3

The present invention relates to a sliding casting machine according to the preamble of claim 1.

It is already known to manufacture hollow-core slab elements using feed screws and guide tubes at their ends. Generally, these machines run on a casting platform supported by impellers and have a nozzle portion around the screws and guide tubes that shapes the shape of the cavity. The machine uses either vibration or compaction or a combination of these to compact the concrete.

Typical of these machines is that they use rigid concrete and the element is so solid immediately after casting that it remains in shape on the casting base without support. However, known methods and devices have various shortcomings and disadvantages. Thus, shaping and compacting a rigid concrete mass into a shape other than the discharge end of the screws requires intense pressure, vibration, or compaction, or a combination thereof. For this reason, the power used to form the element is very high compared to the result obtained. The extra power used causes wear on the screws and the shaping parts of the elements, and for this reason expensive materials have to be used and the service life of the parts is short.

DE patent publication 1 080 916 describes the injection molding of ceramic substances in which the product to be pressed in the form of a rod is formed by deformable disc springs in a nozzle.

DE-A-597 391, on the other hand, describes a device with which an rod-like product can be injection-molded. It uses a bullet-shaped shaping member that can be moved back and forth in the axial direction. Since it is a nozzle, the gap after the movable shaping member tapers.

It is an object of the present invention to provide a sliding casting machine which can avoid the above-mentioned disadvantages.

The machine according to the invention operates by means of feed screws, which provide sufficient casting pressure to the concrete body to be poured in order to cause the concrete to compact. In terms of better flow and compaction of the concrete, the invention uses a continuously expanding and curving groove, which controls the concrete flow and gives the element the desired appearance.

More specifically, the machine according to the invention is mainly characterized by what is set forth in the characterizing part of claim 1.

The machine according to the invention can be used for the production of concrete elements by sliding casting using a very rigid concrete mass. The invention is particularly well suited for the production of concrete hollow core slab elements, but the invention can also be used for the production of large concrete pieces by the sliding casting method. In addition, the invention makes it possible to produce even lighter and higher hollow core slabs and other sliding casting profiles and to use lightened hollow shapes in low hollow core slabs, whereby the number of expensive feed screw units and wearing parts per corresponding profile width is reduced.

The invention will now be considered by means of exemplary embodiments according to the accompanying drawings.

Figure 1 shows a side sectional view of one embodiment of a machine according to the invention.

Figure 2 shows a top view of another embodiment.

Figures 3 and 3a show a side and top view of a third embodiment.

Fig. M is a plan view of a fourth embodiment.

3 7651 3

Figure 5 is a plan view of a fifth embodiment.

Figure 1 shows a machine according to the invention, which moves continuously on wheels 6 and in which the concrete is fed by utilizing the feed screws 3. The feed screw 3 creates a pressure in the closed state of the sliding casting machine, which causes the concrete to compact to some extent. However, the actual compaction of the concrete is achieved by a frictional compaction method in which the concrete is subjected to internally deformable motion. Under pressure, the compacting frictional working of the concrete is effected by a reciprocating concrete flow channel. In terms of good flow and element design, the concrete flow channel is always somewhat widening towards the end. As the sliding casting machine moves forward, the curved channel shapes the concrete back and forth in a direction transverse to the direction of travel of the sliding casting machine, whereby the pressurized, even very rigid concrete is made to compact reliably.

Figure 2 shows a solution model of the invention with which it is possible to produce large cross-sections of concrete from rigid concrete by a sliding casting method. In order to enhance the compaction, the simultaneous reciprocating movement of the sides in the direction of the sliding direction of the side edges 7 is used.

In Figures 3 and 3a, the invention has been applied to the sliding casting of hollow core slabs from rigid concrete. The machine comprises a concrete hopper 2, from which the concrete flows to the feed screw 3. The feed screw and can be one or more depending on the profile to be manufactured. The extensions of the feed screws 3 are hollow mandrels 8. The hollow mandrels 8 are shaped to the desired size and shape. In the height direction, in the width direction in one direction or in all directions, the hollow mandrel 8 may be larger or smaller than the feed screws 3. According to the invention, the hollow mandrel 8 is shaped in such a way that, when the concrete flows at the mandrel 8, the concrete is caused to move back and forth transversely to the direction of travel. Transverse displacements result in a frictional compaction seal rubbing into the concrete mass.

11 7651 3

The cavity mandrels 8 are shaped in such a way that the flow channel of the concrete is always somewhat expandable, and in addition, when going towards the end of the channel, the reciprocating curvature of the channel is less compared to the initial end. In addition, a reciprocating movement in the direction of the sliding casting of the mandrel parts can be used to enhance the compaction. The extension of the hollow mandrel 8 may additionally be a damping mandrel 9.

Figure 4 shows the sliding casting principle according to the invention, according to which a reciprocating concrete flow channel is utilized. The curvature of the channel is achieved by using a flexible tube 10 as a cavity mandrel 10 as an extension of the feed screw 3. The curvature of the hollow mandrel portion is achieved by using an axis of asymmetry 11 formed inside the hollow mandrel portion 10, which is moved back and forth with respect to the longitudinal direction or rotated about its axis in synchronism. The reciprocating motion has the advantage that the concrete flow channel is caused to curve only in the desired direction, i.e. in the horizontal direction, e.g. The axis of asymmetry 11 is shaped so that the curvature of the hollow mandrel 10 is less towards the end.

In Fig. 5, a reciprocating concrete flow channel according to the invention is provided by short, hollow mandrel sections 12 articulated to each other behind the feed screws 3, which are moved in a direction transverse to the direction of travel by an asymmetry axis 11 inside the mandrel sections 12. The concrete-modifying compaction of the curvature of the concrete flow channel can also be enhanced by the reciprocating synchronization of the hollow mandrels with longitudinal movement while the axis of asymmetry 11 remains in place.

Claims (5)

5 7651 3 A sliding casting machine for the production of concrete cavity elements, movable relative to the casting platform, comprising - a hopper (2) or the like, - at least one feeder (3), in particular a feed screw, for applying pressure to the concrete to be poured, - mold edges (7) one cavity mandrel (4, 8-11) for providing a cavity in the feed direction to the element to be manufactured, characterized in that each cavity mandrel (4, 8-11) is shaped in the feed direction so as to have a curved surface so that adjacent cavity mandrels (4, 8-11) or cavity mandrels (4 , 8 - 11) and the formwork edges (7) form at least one reciprocating channel or gap which expands towards the discharge end due to the reciprocating movement, in which the concrete is subjected to a frictional movement transverse to the feed direction. Sliding casting machine according to Claim 1, characterized in that each hollow mandrel (8 to 11) is an extension of its own feed screw (3). Sliding casting machine according to Claim 1, characterized in that the hollow mandrel consists of a jacket (10) of flexible material, the curvature of which can be varied inside the jacket (10) by means of a movable asymmetry axis (11) (Fig. 4). 6 7651 3 Sliding casting machine according to claim 1, characterized in that the hollow mandrel consists of successively articulated mandrel parts (12), the curvature of the mandrel being variable by means of a movable axis of asymmetry (11) passing through all the mandrel parts (12) (Fig. 5). Sliding casting machine according to Claim 1, characterized in that the curvature decreases as it moves towards the discharge end. 7 76513