SYSTEM FOR MANUFACTURING MORTAR-BASED ELEMENTS

Abstract

A system implements a manufacturing method of construction elements including hydraulic binder and aggregates. The system includes a mixing device adapted to mix a dry mortar composition including hydraulic binders and aggregates with water, to form a wet mortar, an outlet, a pumping device adapted to pump and convey the wet mortar towards the outlet, and at least one sensor adapted to measure on-line at least two physical properties of the wet mortar on its way from the mixing device to the outlet, the physical properties including viscosity and at least one of flow and density.

Claims

1. A system for implementing a manufacturing method of construction elements comprising hydraulic binder and aggregates, said system comprising: a mixing device adapted to mix a dry mortar composition comprising hydraulic binders and aggregates with water, to form a wet mortar, an outlet, a pumping device adapted to pump and convey said wet mortar towards said outlet, and at least one sensor adapted to measure on-line at least two physical properties of said wet mortar on its way from said mixing device to said outlet, said physical properties including viscosity and at least one of flow and density.

2. The system according to claim 1, further comprising a non-transitory computer-readable storage media configured to store said at least two physical properties of the wet mortar.

3. The system according to claim 1, wherein the sensor is configured to simultaneously measure the viscosity and at least one of flow and density of the wet mortar.

4. The system according to claim 3, wherein the sensor is of the Coriolis type.

5. The system according to claim 4, wherein the Coriolis type sensor comprises a measuring tube configured to conduct the wet mortar and simultaneously measure the density, the flow, the viscosity and the temperature of the wet mortar.

6. The system according to claim 5, wherein the Coriolis type sensor comprises exactly one measuring tube.

7. The system according to claim 1, further comprising a first controller configured to adjust a ratio between the water and the dry mortar depending on value of at least one of said at least two physical properties.

8. The system according to claim 7, further comprising a water supply and means for adjusting a dosage of mixing water, wherein the first controller is configured to control said means for adjusting the dosage of mixing water.

9. The system according to claim 8, wherein the means for adjusting the dosage of mixing water comprise a valve and a flowmeter.

10. The system according to claim 7, wherein the manufacturing method is a 3-D printing method, said system further comprising a computer-controlled printer having a head comprising said outlet, which is adapted to deposit a layer of mortar on a previous layer of mortar.

11. The system according to claim 10, further comprising the following additional devices: a second controller configured to control the printer, and a central main controller configured to control at least one from the first and second controllers.

12. The system according to claim 7, wherein the first controller is configured to control the pumping device.

13. The system according to claim 11, wherein at least one of the first controller, the second controller, and the central main controller is a programmable logic controller.

14. The system according to claim 1, further comprising a dry mortar storage and a dosing device.

15. The system according to claim 11, wherein the first controller, the second controller, and the central main controller are programmable logic controllers.

Description

[0064] The invention will now be described in more detail by reference to the non-limiting example system shown in FIG. 1.

[0065] FIG. 1 shows an example system according to the invention.

[0066] The system of FIG. 1 is a 3-D printing system comprising a printer having a printer head 20 adapted to extrude wet mortar through a nozzle so as to deposit a layer of wet mortar 11 on a previous mortar layer 12, and to manufacture a construction element 10. The printer is for example an industrial robot or a gantry and the wet mortar may be conveyed to the head through a hose.

[0067] The construction element 10 can be for example a wall, a bridge element, a decorative element, a complex formwork for casting concrete etc.

[0068] The wet mortar is produced by mixing a dry mortar composition with water in a mixing device 40. Mixing is done with a certain mixing ratio.

[0069] The dry mortar composition is stored in a silo 80. Alternatively, the system may comprise several silos or containers containing each of the components of the dry mortar composition, as well as means for mixing the appropriate amounts of each component in order to obtain the desired dry mortar composition.

[0070] The dry mortar composition comprises for example Portland cement, siliceous aggregates, limestone filler, rheology modifiers, additives and fibers.

[0071] Water is stored in a water supply 71, and the dosage of water (impacting the mixing ratio) is adjusted through means 72 comprising for example a valve and a flowmeter. The wet mortar is continuously pumped through a pumping device 50, which is for example a pump, such as a screw pump. The wet mortar is pumped and conveyed towards the printer head 20, and on its way from the mixing device 40 to the printer head 20, at least one of its physical properties is measured on-line by a sensor 30. The measurement is made preferably close to the mixing device.

[0072] The sensor 30 is for example a sensor of the Coriolis type, which is able to measure simultaneously the density, the flow, the viscosity and the temperature of the wet mortar. The system may also comprise another sensor 31 able to measure other properties, for example the pressure.

[0073] The system shown in FIG. 1 is controlled through several controllers. These controllers preferably comprise processors for receiving instructions and/or data and for generating machine instructions executable by other controllers or by specific devices. These controllers can be programmable logic controllers (PLC).

[0074] A central main controller 90 is configured to receive model data specifying a 3D model of the construction element 10 to be printed. These model data are typically stored in a computer-readable storage media 92. The central main controller 90 can be controlled by a controller 91 that may be manually controlled by a user, for example to start or stop the system or to adjust the printing speed. At least one of controllers 90 and 91 comprises an interface, such as a GUI.

[0075] The central main controller 90 is also configured to control the first controller 60 and the second controller 21, for example by generating machine instructions executable by these controllers. These instructions are for example instructions to change the printing speed and/or the height or the width of the layers, according to the model data or the instructions given by the user.

[0076] The second controller 21 controls the printer head 20. It is configured to receive instructions from the central main controller 90 and to generate machine instructions so as to control for example the position and the speed of the printer head 20.

[0077] The first controller 60 controls the system for controlling and adjusting the physical properties of the wet mortar by adjusting the mixing ratio. It is configured to receive data from sensors 30 and 31 and adjust in consequence the flow of mixing water and therefore the mixing ratio by generating instructions executable by the means 72.

[0078] The first controller 60 typically compares in real time the measured value, for example of the viscosity of the wet mortar, with a predetermined range to calculate a control deviation and if needed adjust the water dosage (and therefore the mixing ratio), by adjusting the flow of water.

[0079] The first controller 60 may also generate instructions executable by the pumping device 50, in order for example to adjust the pumping speed according to the desired printing speed.

[0080] The first controller 60 may also generate instructions executable by a third controller 100 that can control the dosage of the dry mortar, for example the flow of the dry mortar. The third controller 100 may also control the mixing of the individual components of the dry mortar.