FI119050B - Method and apparatus for casting concrete products - Google Patents

Abstract

A method and an apparatus for casting concrete products with a substantially horizontal slipforming process, the concrete mass in said method being fed by means of at least one feed element (2) through a limited cross section (11, 7, 8) for forming the concrete product, whereby the feed elements (2) are brought to a dual-frequency longitudinal reciprocal motion for compacting the concrete mass.

Description

119050

METHOD AND EQUIPMENT FOR MOLDING CONCRETE PRODUCTS

The invention relates to the casting of concrete products by substantially horizontal sliding casting, in which the concrete mass is pressurized by at least one feed screw.

More particularly, the invention relates to the movement of a feed screw and / or cavity forming member during casting.

When casting with conventional extruder and slipformer sliding machines, the casting mold consists of a casting base and casting edges and an upper surface 10 which form the cross-section of the article to be molded to the desired shape and size. As the casting machine advances, the casting edges and the upper surface, and, if necessary, the elements forming one or more cavities in the casting product, carry out the compacting movement of the casting mass. The finished product remains on the casting surface to dry. Because the final cast slab remains in the final form lying on the substrate, the known solutions require a high degree of rigidity in known solutions.

The rigid concrete mass used in the prior art results in heavy wear of the sliding machine wear parts, such as feed screws and cavity forming members, which necessitates relatively frequent replacement of these wear parts.

20 When replacing consumables, the production process must also be interrupted by the · · · casting process during that exchange. Rigid concrete mass also causes • · ·. · · ·. high speed mechanical wear and fast-wear • · ·: '. com. loss of compaction power, such as upper surface, side and hollow core rotators and screws ··. "*.

r \ * 25 ···

Sliding casting techniques for making hollow core slabs and solid slabs are generally: V: known. For example, FI80845 describes a method and device (for casting a hollow slab. The described sealing method is based on the reciprocating motion of the hollow sleeve.:. Simultaneously with the reciprocal length movement. # wobble does not achieve sufficient concrete sealing in high cavities.

• · 119050 2

FI 85350 discloses a sealing method in which the wedge surfaces are moved in the downstream and opposite direction with respect to one another. However, the effect of the wedge surfaces on the compaction of the concrete remains very small, since the wedge surfaces have to be slanting in relation to the flow of the concrete, thereby reducing the property of reducing or widening the concrete compaction area. On deep wedges, concrete flow is prevented.

EP 1 033 213 discloses a solution for generating a reciprocating sealing movement of a feeder of an extruder-type sliding machine, in which the amplitude and frequency of the sealing movement can be adjusted. DE 2 225 413 discloses 10 sliding machines in which the mass is fed into a sliding mold and compacted by a reciprocating part, the part of which is adjustable in frequency and amplitude.

In known extruder-type sliding machines, the feed screw and hollow-tune reciprocating motion are 5 to 50 mm long and the reciprocating motion frequency is 1 to 10 Hz.

15

The present invention provides a sliding casting machine of simple construction, comprising a dual-frequency compaction process which provides a better than usual compaction result with less component wear.

... 20 In this context, the dual-frequency compression method refers to a · · ♦ compaction method where the mass is compacted simultaneously at two different frequencies.

More particularly, the process according to the invention is characterized by what is stated in the characterizing part of claim 1 and the invention; * * *. 25 equipment, as set forth in the characterizing part of claim 4.

»··: ': *; The invention will now be described in more detail by way of example with reference to the following figure ♦, where:. Fig. 1 schematically shows a sliding casting machine according to the invention.

· * ·· 30 • · »··

The main components of the sliding machine shown in Figure 1 are the pulp container 1, feed screw 2, ··· feed screw actuators 3,4 and 5, hollow core 6, side edges 7, trowel 8, trowel actuator 9, surface leveling plate 10, casting motor 11, and • · 119050 3 Feed screw trough 13. The apparatus shown in the figure is for casting hollow slabs or beams.

In the casting machine shown in Figure 1, a rigid concrete mass is fed from 5 pulp containers 1 to one or more feed screws 2. Each feed screw 2 is disposed in a trough 13 which, at the beginning of the feed screw, guides the concrete mass to the feed screw. The feed screws 2 extrude the concrete mass under pressure into a limited cross-section formed by the base 11, side plates 7 and trowel 8, which defines the outer dimensions of the product to be cast. The rotation movement caused by the concrete mass extrusion 10 of the feed screws 2 is effected by a rotary movement actuator 3. After the feed screws 2, cavity cores 6, which form cavities in the product to be cast, are inserted after casting the cavities.

The casting machine moves along the casting surface by the reaction force 15 exerted by the feed screws 2, which is further enhanced or resisted by the drive motor 12 connected to the casting wheels.

The product to be cast is compacted by the reciprocating movement of the feed screws 2 and the hollow cores 6, and by the sealing traverse of the side plates 7 and the trowel 8 which, in the case of the trowel 20, is achieved by trowel actuators 9. Trowel 8 * · ·. ·: ·, The following surface leveling plate 10 smoothes the top surface of the final product.

The return movement of the feed screws 2 and the hollow cores 6 is dual-frequency, which movement is achieved by the long-motion actuator 5 and the short-motion actuator 4.

. ***. 25 In this case, during one long reciprocating movement of the actuator 5, the actuator ·· * 4 performs several reciprocal movements. Thus, the sealing member assembly formed by the feed screws 2 and the hollow cores 6: V performs several short reciprocating movements • ·:: simultaneously, this sealing member assembly performs one long reciprocating motion.

In the solution of the invention, the short reciprocating motion is preferably between 0.2 and 4 mm and the frequency is preferably between 15 and 50 Hz. The length and frequency of the long forward movement of the solution of the invention according to the invention are substantially equal to that of known solutions, i.e., 5 to 40 mm in length and 1 to 10 Hz in frequency.

Such a dual-frequency sealing movement of the invention results in short movement for 5: • effective machining of the concrete mass, whereby the concrete mass is already partially compacted by the portion of the feed screw; can be omitted, for long motion: • providing a sealing event over the entire length of the cavity inch, and • enhancing the supply of concrete mass to a maximum cross-section pressure of 15.

The combination of long and short movement also allows for a lower feed screw pitch due to enhanced concrete mass feeding and sealing, which results in a higher casting machine casting speed and at the same time a lower feed screw relative wear.

The solution according to the invention is not limited only to the method and apparatus for casting concrete products with cavities, as shown in the example in the figure, but can also be applied to, for example, casting solid solid tiles • t · '... · 25. In this case, the cavity forming members are removed from the casting apparatus, and only the feed dots / nuts are moved back and forth by the dual-frequency * · \ V sealing movement of the invention.

The solution of the invention may also be implemented in a fixed casting station, wherein: the casting apparatus is located in a fixed casting station but the casting base moves relative to the casting station. In this case, the moving casting unit moves the finished product out of the fixed *** · ....: casting station and the finished product remains lying on the casting base.

Claims (9)

Method for casting concrete products by substantially horizontal sliding molding, in which method concrete mass is measured with at least one feed member (2) through a limited cross-section (11, 7, 8) to form a concrete product, characterized in that the feed means (2) is placed in a two-frequency longitudinal pendulum movement for sealing the concrete mass. Process according to claim 1, characterized in that the cast product is a concrete product having at least one hollow concrete product, in which, in addition to the feeding means (2), a hollow forming member (6) is placed in a two frequency longitudinal pendulum movement. 3. A method according to claim 1 or 2, characterized in that the length of the choroidal pendulum movement's pendulum movement is 0.2-4 mm and frequency is 15-50 Hz, and the length of its long pendulum motion is 5-40 mm and frequency is 1- 10 Hz. Apparatus for casting concrete products by substantially horizontal sliding molding, which apparatus comprises at least one feeding means (2) for feeding concrete mass through a limited cross-section (11, 7, 8) to form a concrete product characterized by , that the apparatus comprises means (4, 5) for • · ·. *; ·, Insertion of the feed means (2) into a two-frequency longitudinal pendulum movement for sealing. of the concrete mass. • · • «v ··· • · • · ··· r. ( Apparatus according to claim 4, characterized in that the apparatus comprises means; * * * j (6) for forming at least one heel space in the concrete product to be molded, which means (**) are provided together with the feeding means (2) in a two-frequency longitudinal direction: Y: pendulum movement. • · ··· • · · · * ·· Apparatus according to claim 4 or 5, characterized in that the length of ····. * * ·. And the frequency of its long pendulum motion is 5-40 mm and frequency is 1-10 Hz. · «·· • · 119050 Apparatus according to any one of claims 4-6, characterized in that the feeding means is a feeding screw (2). Apparatus according to any of claims 4-7, characterized in that the apparatus 5 comprises means (12) for moving the apparatus along a casting base (11) during the casting. 9. Apparatus according to any of claims 4-7, characterized in that the apparatus comprises a fixed casting station and movable casting substrates. • · · • · · · ♦ ··· • · · · 1 · * · · · · · · 1 · • · · · · · · · · · · · · 1 ··· • · • 1 • a · · · «1 · • · * ·· • · · · ··· • · · ** · 1 • · * · • · · · · · · · · 1