EP-4735707-A1 - CONCRETE PUMP

EP4735707A1EP 4735707 A1EP4735707 A1EP 4735707A1EP-4735707-A1

Abstract

A concrete pump comprising a pre-filling container, a delivery pipe (17) and a pump device (29) for delivering liquid concrete from the pre-filling container through the delivery pipe (17). Unlike the pre-filling containers in conventional concrete pumps, the pre-filling container is in the form of a pre-filling shaft (16) and not a pre-filling funnel.

Inventors

STREBLE, Benedikt
HÄFNER, Jens

Assignees

Putzmeister Engineering GmbH

Dates

Publication Date: 20260506
Application Date: 20240626

Claims (15)

1. Concrete pump, comprising a pre-filling container, a conveyor line (17) and a pumping device (29) for conveying liquid concrete from the pre-filling container along the conveyor line (17), wherein the pre-filling container is designed as a pre-filling shaft (16).
2. Concrete pump according to claim 1, wherein the concrete pump is designed to produce concrete structures by 3D printing, wherein a metering pump is arranged in the delivery line, and wherein an outlet end of the delivery line (17) is designed as a print head (37).
3. Concrete pump according to claim 1 or 2, wherein a filling cross-section (44) of the pre-filling shaft (16) is no more than 50%, preferably no more than 30%, more preferably no more than 10% larger than a suction cross-section (45) of the pre-filling shaft (16).
4. Concrete pump according to one of claims 1 to 3, wherein a wall (46) of the pre-filling shaft (16) arranged between the filling cross-section (44) and the suction cross-section (45) is aligned such that the angle included with the vertical is less than 16°, preferably less than 8°, more preferably less than 4°.
5. Concrete pump according to one of claims 1 to 4, comprising a sieve (35) with which the liquid concrete is sieved before entering the pre-filling shaft (16).
6. Concrete pump according to claim 5, wherein the pre-filling shaft (16) has an upper end edge (34) on which the sieve (35) rests.
7. Concrete pump according to one of claims 1 to 6, wherein the wall (46) of the pre-filling shaft (16) consists of a rigid material in a lower portion of the pre-filling shaft (16) and of an elastic material (57) in an upper portion of the pre-filling shaft (16).
8. Concrete pump according to one of claims 1 to 7, comprising an agitator (50, 55, 56) for setting liquid concrete contained in the pre-filling shaft (16) in motion.
9. Concrete pump according to claim 8, wherein the agitator (50, 55, 56) has a smaller distance to a distal end (49) of the pre-filling shaft (16) than to a proximal end (48) of the pre-filling shaft.
10. Concrete pump according to claim 8 or 9, wherein the agitator (50, 55, 56) has a stirring blade (53) and wherein the stirring blade (53) is provided with an opening (61).
11. Concrete pump according to one of claims 78 to 10, comprising a first agitator (55) and a second agitator (56), wherein the agitators (55, 56) are arranged on two sides of a longitudinal center plane (54) of the pre-filling shaft (16).
12. Concrete pump according to one of claims 8 to 11, wherein the distance between the stirring blades (53) of the first agitator (55) and the stirring blades (56) of the second agitator (56) is smaller, preferably at least 20% smaller, more preferably at least 40% smaller than the radial span spanned by the stirring blades (53) of an agitator (55, 56).
13. Concrete pump according to one of claims 1 to 12, wherein the pre-filling shaft (16) has a smaller width at the distal end (49) of the pre-filling shaft (16) than at the proximal end (48) of the pre-filling shaft (16).
14. Concrete pump according to one of claims 1 to 13, wherein the pre-filling shaft (16) has a volume between 200 l and 700 l, preferably a volume between 300 l and 600 l.
15. Concrete pump according to one of claims 1 to 14, wherein the pre-filling shaft (16) is designed as an insert (60) which is designed to be inserted into a pre-filling funnel (59) of a concrete pump.

Description

concrete pump The invention relates to a concrete pump. Various applications use liquid concrete which has a higher viscosity than previously used. These include, for example, 3D printing processes which produce a concrete structure without the shape of the concrete structure being predetermined by formwork. During 3D printing, the liquid concrete is conveyed in such a way that it emerges from the outlet end of a conveyor line in the form of a strand with a predetermined cross-section. When it emerges from the conveyor line, the liquid concrete has a consistency such that the cross-section of the strand is retained when the strand is placed on a surface. It has been shown that problems arise when liquid concrete with high viscosity is pumped with a conventional concrete pump. The invention is based on the object of presenting a concrete pump which avoids these disadvantages. The object is achieved with the features of the independent claims. Advantageous embodiments are specified in the subclaims. A concrete pump according to the invention comprises a pre-filling container, a delivery line and a pumping device for conveying liquid concrete from the pre-filling container along the delivery line. The pre-filling container is designed as a pre-filling shaft, which distinguishes the invention from conventional concrete pumps in which the pre-filling container is designed as a pre-filling funnel. In conventional concrete pumps, which are used to pump liquid concrete with a lower viscosity, the pre-filling tank is designed as a pre-filling funnel. The funnel shape allows The pre-filling container must have a large volume and a large filling opening, which allows the liquid concrete to be easily filled in. The inclined funnel surfaces concentrate the liquid concrete in a narrower area at the lower end of the pre-filling container, so that it can be easily sucked in by the pumping device of the concrete pump. In contrast, the invention proposes designing the pre-filling container as a pre-filling shaft so that the liquid concrete can move essentially vertically downwards between the filling opening and the area of the pre-filling container into which it is sucked in by the pumping device. By avoiding a strong spatial constriction between the upper end and the lower end of the pre-filling container, the liquid concrete moves essentially parallel to gravity, thereby reducing the risk of the liquid concrete sticking to the wall of the pre-filling container. It is undesirable for liquid concrete to stick to the wall of the pre-filling container because it dries quickly and then no longer has the desired consistency. If such liquid concrete were to subsequently get into the conveyor line, this could result in the conveyor process being disrupted and being unable to continue. Through the pre-filling shaft according to the invention, the liquid concrete that was first filled into the pre-filling shaft is first sucked in with the pump device (first in first out, FI FO). This prevents partial quantities of the liquid concrete from remaining in the pre-filling shaft for too long. In conventional pre-filling tanks, the filling cross-section is significantly larger than the suction cross-section. The filling cross-section and suction cross-section refer to the horizontal cross-section of the pre-filling tank in two different height positions, assuming that the concrete pump is standing on a level surface. The lower height position The height position at which the suction cross-section is located corresponds to the uppermost area from which liquid concrete is sucked in, which normally corresponds to the upper end of an inlet opening of the pumping device. The upper height position at which the filling cross-section is located corresponds to the height position up to which the pre-filling container can be filled before it overflows. The pre-filling shaft according to the invention is preferably designed in such a way that the filling cross-section is no more than 50%, preferably no more than 30%, more preferably no more than 10% larger than the suction cross-section. This information refers to the surface area of the area covered by the filling cross-section or the suction cross-section. Embodiments are possible in which the filling cross-section is no larger than the suction cross-section or in which the filling cross-section is smaller than the suction cross-section. Such a ratio between the filling cross-section and the suction cross-section ensures that the liquid concrete moves essentially downwards in the pre-filling shaft and that no major constriction in the horizontal direction is required. A conventional pre-filling funnel is essentially limited by inclined wall surfaces through which the liquid concrete is horizontally collected on its way downwards from the large filling cross-section to the small suction cross-section. The pre-filling shaft according to the invention offers the advantage that such inclined wall su