JP2020116831A - Cement slurry discharging device - Google Patents

Abstract

To provide a cement slurry discharging device useful for producing a three-dimensional molded body as designed without imposing excessive work load at a construction site.SOLUTION: A discharging device of this invention which is for discharging cement slurry having a hydraulic property comprises: a device main part; a first container detachably attached to the device main part and storing a cement-containing liquid that contains cement, water, inorganic acid, and a thickener; a second container detachably attached to the device main part and storing an alkaline liquid; a mixer that mixes the cement-containing liquid and the alkaline liquid to obtain the cement slurry; first transfer means that transfers the cement-containing liquid in the first container to the mixer; second transfer means that transfers the alkaline liquid in the second container to the mixer; and a discharge port that discharges the cement slurry from the mixer.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a cement slurry discharging device.

In recent years, a technique for producing a three-dimensional object using a molding material such as metal, resin, or cement has been drawing attention. For example, Patent Document 1 discloses a cement composition applied to an additional manufacturing apparatus (3D printer) and a method for manufacturing a cementitious hardened body using the cement composition.

JP, 2017-24979, A

There are the following problems in using a cement slurry having hydraulic properties as a modeling material to manufacture a three-dimensional model with an additional manufacturing apparatus. That is, the three-dimensional molded object made of the cement hardened body is constructed by sequentially stacking the cement slurries discharged from the nozzle of the additional manufacturing apparatus. Therefore, in order to manufacture a three-dimensional molded article as designed, it is required that the cement slurry after discharge is hardened within a short time and reaches the strength at which it is not crushed by the weight of the newly laminated cement slurry. On the other hand, if a cement slurry that hardens in a short time is prepared and used each time at the construction site, the burden on the construction site will be great and the spread of the technology will be hindered.

The present disclosure has been made in view of the above problems, and an object of the present invention is to provide a discharge device for a cement slurry that is useful for producing a three-dimensional object as designed without imposing an excessive burden on a construction site. And

A discharge device according to one aspect of the present disclosure is for discharging a cement slurry having hydraulic properties, and is provided detachably with respect to a device main body and the device main body, and includes cement, water, and an inorganic material. A first container for containing a cement-containing liquid containing an acid and a thickening agent, a second container detachably provided for the apparatus main body and containing an alkaline solution, a cement-containing liquid and an alkaline solution A mixer for obtaining a cement slurry by mixing with, a first transfer means for transferring the cement-containing liquid in the first container to the mixer, and a first for transferring the alkaline solution in the second container to the mixer. The second transfer means and the discharge port for discharging the cement slurry from the mixer are provided.

According to the above discharging device, in the state where the cement-containing liquid and the alkaline solution are separately stored in the first and second containers, the hydration reaction of cement does not proceed, and both are mixed in the mixer. This allows the hydration reaction of cement to proceed. Therefore, the hardening rate of the cement due to the hydration reaction can be easily set appropriately according to the size of the three-dimensional object, the laminating method, and the like, and the three-dimensional object can be sufficiently manufactured as designed. Moreover, since the first and second containers are detachably attached to the apparatus main body, the load on the construction site can be sufficiently reduced. For example, if a cement-containing liquid or an alkaline solution is prepared in a well-equipped manufacturing factory and the container containing this is delivered to the construction site, the replacement work with a container with a low remaining amount can be easily performed. ..

The viscosity of the cement-containing liquid is preferably a non-Newtonian fluid from the viewpoint of suppressing the deformation of the cement slurry due to its own weight after discharge and achieving good fluidity during discharge of the cement slurry. That is, the viscosity of the cement-containing liquid measured at a temperature of 20° C. and a shear rate of 10 s ⁻¹ is, for example, ^{1 to} 20 Pa·s, and is measured at a temperature of 20° C. and a shear rate of 0.1 s ^−1. The viscosity of the cement-containing liquid is, for example, 50 to 500 Pa·s.

The volume of the first container and the second container may be appropriately set according to the amount of the cement-containing liquid and the alkaline solution contained in these containers, and the volume of the first container is 100 parts by volume, The volume of the second container is, for example, 1 to 40 parts by volume.

The configurations of the first and second transfer means may be adapted to suit the scale of the discharge device (for example, the discharge amount per unit time). When the discharge device has a relatively large scale (for example, the volume of the first container: 1 to 1000 L), the first and second transfer means may include a pump. That is, the first transfer means includes a first flow path from the first container to the mixer, and a first pump provided in the middle of the first flow path, and the second transfer means is A second flow path from the second container to the mixer, and a second pump provided in the middle of the second flow path may be included. On the other hand, when the discharge device has a relatively small size (for example, the volume of the first container: 0.01 to 1 L), the first and second transfer means can be configured to include a piston. That is, the first transfer means is a first piston that slides against the inner surface of the first container, and a first piston that transfers the cement-containing liquid extruded from the first container by the first piston to the mixer. And a second transfer means for mixing the second piston that slides with respect to the inner surface of the second container and the alkaline solution that is extruded from the second container by the second piston. It can be configured to include a second flow path for transferring to a container.

The discharge device may further include a drive mechanism for moving the discharge port in the horizontal direction and the vertical direction. By adopting such a configuration, the discharge device can be used as an additional manufacturing device (3D printer), and a three-dimensional molded object made of a cement hardened product can be manufactured.

According to the present disclosure, there is provided a cement slurry discharge device useful for producing a three-dimensional object as designed without imposing an excessive burden on the construction site.

FIG. 1 is a front view schematically showing a first embodiment of a discharge device according to the present disclosure. FIG. 2 is a sectional view schematically showing a second embodiment of the ejection device according to the present disclosure.

Hereinafter, a plurality of embodiments of the present disclosure will be described. It should be noted that the same components will be denoted by the same reference symbols for the sake of convenience and will not be described repeatedly.

<First embodiment>
FIG. 1 is a front view schematically showing the ejection device according to the first embodiment. The discharge device 10 shown in this figure is for discharging a cement slurry having hydraulic properties. The discharge device 10 is of a relatively large scale, and the discharge amount of cement slurry per unit time is, for example, about 0.3 to 10 L/min.

The discharge device 10 transfers a first container 1 containing a cement-containing liquid, a second container 2 containing an alkaline solution, a mixer 3 for mixing the cement-containing liquid and the alkaline solution, and a cement slurry. The hose 5 and the nozzle 7 provided at the tip of the hose 5 are provided. Cement slurry is prepared by mixing the cement-containing liquid and the alkaline solution in the mixer 3, and the cement slurry is discharged from the nozzle 7. Hereinafter, each component of the ejection device 10 will be described.

The first container 1 contains a cement-containing liquid. The first container 1 is supported by the main body 8 of the apparatus and is detachably attached to the frame 8a. Therefore, the cement-containing liquid is prepared in a well-equipped manufacturing factory, and another first container 1 containing the same is delivered to the construction site, so that the first container 1 with less remaining is replaced. Work can be performed easily. The first container 1 has an opening/closing valve 1v at the bottom, and a hose 1a is connected to the opening/closing valve 1v.

The second container 2 contains an alkaline solution. The second container 2 is supported by the apparatus main body 8 and is detachably attached to the frame 8b. Therefore, by preparing an alkaline solution in a well-equipped manufacturing factory and delivering another second container 2 containing this to the construction site, replacement work with a second container with less remaining Can be done easily. The second container 2 has an opening/closing valve 2v at the bottom, and a hose 2a is connected to the opening/closing valve 2v.

The capacities of the first container 1 and the second container 2 may be appropriately set according to the amounts of the cement-containing liquid and the alkaline solution contained in these containers. Assuming that the amount of the cement-containing liquid used for preparing the cement slurry is 100 parts by volume, the amount of the alkaline solution used is, for example, about 1 to 40 parts by volume, so the volume of the second container 2 is the first container. It may be sufficiently smaller than the capacity of 1. That is, assuming that the volume of the first container 1 is 100 parts by volume, the volume of the second container 2 may be, for example, 1 to 40 parts by volume, and the lower limit value is 1.2 parts by volume or 1.4 volumes. Parts, and the upper limit may be 38 parts by volume or 37 parts by volume. The capacity of the first container 1 is, for example, 1 to 1000 L, the lower limit value may be 2 L or 4 L, and the upper limit value may be 900 L or 800 L. The capacity of the second container 2 is, for example, 0.01 to 400 L or more, the lower limit value may be 0.012 L or 0.015 L, and the upper limit value may be 380 L or 370 L.

The discharge device 10 comprises a first transfer means for transferring the cement-containing liquid from the first container 1 to the mixer 3, and a second transfer means for transferring the alkaline solution from the second container 2 to the mixer 3. Prepare In the present embodiment, the first transfer means includes a hose 1a (first flow path) connected from the first container 1 to the mixer 3 and a first pump 1b provided in the middle of the hose 1a. Is configured. In the present embodiment, the second transfer means includes a hose 2a (second flow path) connected from the second container 2 to the mixer 3 and a second pump 2b provided in the middle of the hose 2a. Is configured.

The first pump 1b can be appropriately selected according to the viscosity of the cement-containing liquid, the liquid-feeding speed of the cement-containing liquid, the pressure loss due to the cement-containing liquid, and the like. For example, a snake pump, a squeeze pump, a blanker pump, etc. You can Since the first pump 1b is intended for a cement-containing liquid (a liquid containing powder and particles), it is preferable to adopt a snake pump or a squeeze pump. The second pump 2b can be appropriately selected depending on the viscosity of the alkaline solution, the liquid feeding speed of the alkaline solution, the pressure loss due to the alkaline solution, and the like, and may be, for example, a snake pump, a squeeze pump, a blanker pump, or the like.

The mixer 3 is composed of a front chamber 3a that receives a cement-containing liquid and an alkaline solution from different inlets, and a static mixer 3b that is provided on the downstream side of the front chamber 3a. The static mixer 3b does not require power and has an effect of energy saving. The mixer 3 may be any one as long as it can mix the cement-containing liquid and the alkaline solution sufficiently uniformly, and is composed of, for example, a tank containing the cement-containing liquid and the alkaline solution, and a propeller for stirring the liquid in the tank. It may be one that is done.

The hose 5 is for transferring the cement slurry from the mixer 3 to the nozzle 7. The flow of cement slurry in the hose 5 is due to the discharge pressure of the pumps 1b and 2b. When the discharge pressure of the pumps 1b and 2b is insufficient, a pump (for example, a squeeze pump) may be arranged in the middle of the hose 5.

The nozzle 7 is for discharging the cement slurry. By moving the nozzle 7 in the horizontal direction and the vertical direction while discharging the cement slurry from the nozzle 7, it is possible to manufacture a three-dimensional molded object made of a hardened cement material. The shape of the discharge port 7a of the nozzle 7 may be appropriately set depending on the viscosity and the discharge speed of the cement slurry, the mode of the three-dimensional model, and the like. The ejection device 10 may further include a drive mechanism (not shown) that moves the nozzle 7 in the horizontal direction and the vertical direction. By adopting such a configuration, the ejection device 10 can be used as an additional manufacturing device (3D printer).

According to the discharge device 10 of the present embodiment, when the cement-containing liquid and the alkaline solution are contained in separate containers, the hydration reaction of cement does not proceed, and both are mixed in the mixer 3. The cement hydration reaction can proceed. Therefore, the hardening rate of the cement due to the hydration reaction can be easily set appropriately according to the size of the three-dimensional object, the laminating method, and the like, and the three-dimensional object can be sufficiently manufactured as designed. Hereinafter, the cement-containing liquid, the alkaline solution and the cement slurry will be described.

(Cement-containing liquid)
The cement-containing liquid contains cement, water, an inorganic acid and a thickener. The cement-containing liquid becomes a cement slurry having hydraulicity when the alkaline solution is mixed.

The cement is not particularly limited, but may be, for example, ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, moderate heat Portland cement, low heat Portland cement, blast furnace cement, fly ash cement, silica fume cement, alumina cement, etc. .. Cement can be used individually by 1 type or in combination of 2 or more types.

The water is not particularly limited, but tap water, distilled water, deionized water, or the like can be used, for example. The content of water is preferably 20 to 100 parts by mass, more preferably 25 to 90 parts by mass, and further preferably 30 to 80 parts by mass with respect to 100 parts by mass of cement.

The inorganic acid preferably contains metaphosphoric acid, phosphorous acid, phosphoric acid, or phosphonic acid. As the inorganic acid containing metaphosphoric acid, phosphorous acid, phosphoric acid, or phosphonic acid, for example, diphosphorus pentoxide, diphosphoric acid, triphosphoric acid, aminotrimethylenephosphonic acid, 2-aminoethylphosphonic acid, 1- Hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetramethylenephosphonic acid, tetramethylenediaminetetramethylenephosphonic acid, hexamethylenediaminetetramethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid, phosphonobutanetricarboxylic acid, N-(phosphonomethyl)imino It may be diacetic acid, 2-carboxyethylphosphonic acid, 2-hydroxyphosphonocarboxylic acid or the like. The inorganic acids may be used alone or in combination of two or more. The content of the inorganic acid is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, further preferably 0.1 to 10 parts by mass, and particularly preferably 0 to 100 parts by mass of cement. 3 to 10 parts by mass.

The thickener preferably contains xanthan gum, diutan gum, starch ether, guar gum, polyacrylamide, carrageenan gum, agar, and clay mineral type bentonite. The thickeners may be used alone or in combination of two or more. In addition, the above-mentioned thickener may be used in combination with a cellulose-based, protein-based, latex-based, or water-soluble polymer-based thickener.

The cement-containing liquid may contain aggregate, ink, pigment, dispersant, setting modifier, expansion material, shrinkage reducing agent, gypsum, defoaming agent, etc., in addition to cement, water, inorganic acid and thickener. Good.

As the aggregate, fine aggregate, coarse aggregate and the like can be used. The fine aggregate is not particularly limited, and river sand, land sand, sea sand, crushed sand, silica sand, hard blast furnace slag fine aggregate, blast furnace slag fine aggregate, copper slag fine aggregate, electric furnace oxidized slag fine aggregate, etc. are used. can do. The coarse aggregate is not particularly limited, and gravel, crushed stone, blast furnace slag coarse aggregate, electric furnace oxidized slag coarse aggregate, and the like can be used. In addition, as specified in JIS A 0203:2014 “Concrete terminology”, fine aggregate is an aggregate that passes through a 10 mm mesh sieve all the way through a 5 mm mesh sieve by 85% or more by mass, and a coarse aggregate is It is an aggregate that retains 85% or more by mass on a 5 mm mesh sieve. When the cement-containing liquid contains only fine aggregate as the aggregate, the content of the aggregate in the cement-containing liquid is, for example, 70% by mass or less based on the total mass of the cement and the aggregate, and 65% by mass. Or less or 60% by mass or less. When the cement-containing liquid contains fine aggregate and coarse aggregate as the aggregate, the content of the aggregate in the cement-containing liquid is, for example, 90% by mass or less based on the total mass of the cement and the aggregate, It may be 87% by mass or less or 85% by mass or less. The content ratio of the fine aggregate in the aggregate is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and further preferably 40 to 55% by mass.

The viscosity of the cement-containing liquid is preferably a non-Newtonian fluid from the viewpoint of suppressing the deformation of the cement slurry after discharge due to its own weight and achieving good fluidity during discharge of the cement slurry. That is, the viscosity of the cement-containing liquid measured under the conditions of a temperature of 20° C. and a shear rate of 10 s ⁻¹ is, for example, ^{1 to} 20 Pa·s or more, and the lower limit value may be 2 Pa·s or 3 Pa·s, The upper limit may be 15 Pa·s or 10 Pa·s. The viscosity of the cement-containing liquid measured under the conditions of a temperature of 20° C. and a shear rate of 0.1 s ⁻¹ is, for example, 50 to 500 Pa·s, and the lower limit value may be 60 Pa·s or 70 Pa·s, and the upper limit. The value may be 480 Pa·s or 470 Pa·s. The viscosity of the cement-containing liquid can be adjusted, for example, by adjusting the water-cement ratio or the blending amount of the thickener.

(Alkaline solution)
The alkaline solution is not particularly limited as long as it has a pH of more than 7 and 14 or less, but a solution having a pH of 9 or more and 14 or less is preferable. The alkaline solution may be, for example, a solution containing sodium hydroxide, amine, alkanolamine, sodium orthosilicate, lithium hydroxide, aminomethylpropanol, calcium hydroxide or the like.

The viscosity of the alkaline solution is not particularly limited, and for example, the viscosity of the alkaline solution measured at a temperature of 20° C. and a shear rate of 10 s ⁻¹ is, for example, 0.5 to 3 mPa·s, and the lower limit value is 0. It may be 0.6 mPa·s or 0.7 mPa·s, and the upper limit may be 2.8 mPa·s or 2.7 mPa·s.

(Cement slurry)
The pot life of the cement slurry discharged from the mixer 3 is adjusted by changing the water-cement ratio of the cement-containing liquid and the alkaline solution, the dissolved mass of the alkaline solution, the type of solute, the amount of gypsum, the concentration of the inorganic acid, etc. can do. The pot life may be, for example, 30 seconds to 300 minutes, the lower limit value may be 40 seconds or 60 seconds, and the upper limit value may be 250 minutes or 200 minutes.

The cement slurry may contain a coloring component in addition to the cement-containing liquid and the alkaline solution. Examples of the coloring component include paint and pigment. The coloring component may be added in any step until the cement slurry is obtained. For example, the coloring component may be contained in the cement-containing liquid or the alkaline solution, or may be directly added to the mixer 3. From the viewpoint of preparing a sufficiently uniformly colored cement slurry in the mixer 3, it is preferable that the cement-containing liquid, which is used in a larger amount than the alkaline solution, contains a coloring component in advance.

<Second embodiment>
FIG. 2 is a cross-sectional view schematically showing the ejection device according to the second embodiment. The discharge device 20 shown in this figure is smaller than the discharge device 10 according to the first embodiment, and the discharge amount of cement slurry per unit time is, for example, about 0.01 to 1 L/min. ..

The discharge device 20 includes a first container 11 containing a cement-containing liquid, a second container 12 containing an alkaline solution, a mixer 13 for mixing the cement-containing liquid and the alkaline solution, and an outlet of the mixer 13. And a nozzle 17 provided in the. A cement slurry is prepared by mixing the cement-containing liquid and the alkaline solution in the mixer 13, and the cement slurry is discharged from the nozzle 17. The discharge device 20 has a device body 18 in which the first container 11 and the second container 12 are detachably provided, and the device body 18 is horizontally and vertically moved by a drive mechanism (not shown). Moving. Since the discharge device 20 does not need a hose that connects the mixer 13 and the nozzle 17, it has an advantage that material loss can be sufficiently reduced.

Hereinafter, the configuration of the ejection device 20 will be described mainly regarding differences from the ejection device 10.

The volume of the first container 11 is, for example, 0.01 to 1 L or more, the lower limit value may be 0.02 L or 0.04 L, and the upper limit value may be 0.9 L or 0.8 L. The capacity of the second container 12 is, for example, 0.001 to 0.4 L or more, the lower limit value may be 0.0012 L or 0.0015 L, and the upper limit value may be 0.38 L or 0.37 L. ..

The discharge device 20 has a first transfer means for transferring the cement-containing liquid from the first container 11 to the mixer 13, and a second transfer means for transferring the alkaline solution from the second container 12 to the mixer 13. Prepare In the present embodiment, the first transfer means includes a first piston 11a that slides on the inner surface of the first container 11 and a cement-containing liquid that is extruded from the first container 11 by the first piston 11a. It is configured by a hose 11b (first flow path) that is transferred to the mixer 13. In the present embodiment, the second transfer means mixes the second piston 12a that slides with respect to the inner surface of the second container 12 and the alkaline solution extruded from the second container 12 by the second piston 12a. It is constituted by a hose 12b (second flow path) which is transferred to the container 13.

The first piston 11a is configured to be driven by power such as manual, electric, hydraulic, or pneumatic (blanger), so that the transfer amount of the cement-containing liquid to the mixer 3 can be adjusted. The second piston 12a is driven by power such as manual, electric, hydraulic, or pneumatic (blanger), and is configured to adjust the transfer amount of the alkaline solution to the mixer 13. The first piston 11a and the second piston 12a may be configured by one axis (the shaft 11c and the shaft 12c are integrally formed), or may be configured by two axes (the shaft 11c and the shaft 12c are independent from each other. Formed). In the case of the uniaxial construction, the moving distances of the first piston 11a and the second piston 12a are the same, so the mixing ratio of the two liquids is determined by the cross-sectional area of the containers 11 and 12. On the other hand, in the case of being constituted by two axes, the composition ratio of the two liquids can be arbitrarily set by controlling both independently.

1, 11... First container, 1a, 11b... Hose (first flow path), 1b... First pump, 2, 12... Second container, 2a, 12b... Hose (second flow path) 2b... Second pump, 3, 13... Mixer, 3a... Anterior chamber, 3b... Static mixer, 5... Hose, 7, 17... Nozzle, 7a... Discharge port, 8, 18... Device body, 11a... 1st piston, 12a... 2nd piston

Claims (9)

A cement slurry discharge device having hydraulic properties,
The device body,
A first container that is provided detachably with respect to the apparatus main body, and that holds a cement-containing liquid containing cement, water, an inorganic acid, and a thickener,
A second container that is detachably attached to the apparatus main body and stores an alkaline solution,
A mixer for mixing the cement-containing liquid and the alkaline solution to obtain the cement slurry,
A first transfer means for transferring the cement-containing liquid in the first container to the mixer;
Second transfer means for transferring the alkaline solution in the second container to the mixer;
A discharge port for discharging the cement slurry from the mixer,
An apparatus for discharging cement slurry, comprising: The discharge device for cement slurry according to claim 1, wherein the cement-containing liquid has a viscosity of ^{1 to} 20 Pa·s measured at a temperature of 20°C and a shear rate of 10 s ^-1 . The cement slurry discharging device according to claim 1 or 2, wherein the cement-containing liquid has a viscosity of 50 to 500 Pa·s measured at a temperature of 20°C and a shear rate of 0.1 s ^-1 . The cement slurry discharging device according to claim 1, wherein the volume of the first container is 100 parts by volume, and the volume of the second container is 1 to 40 parts by volume. The first transfer means includes a first flow path from the first container to the mixer, and a first pump provided in the middle of the first flow path,
The second transfer means includes a second flow path from the second container to the mixer, and a second pump provided in the middle of the second flow path. 4. The cement slurry discharging device according to any one of 4 above. The cement slurry discharging device according to claim 5, wherein the volume of the first container is 1 to 1000 L. The first transfer means is a mixer that mixes the first piston that slides against the inner surface of the first container and the cement-containing liquid extruded from the first container by the first piston. And a first flow path to transfer to,
The second transfer means, a second piston sliding against the inner surface of the second container, and the alkaline solution extruded from the second container by the second piston to the mixer. The discharge device of the cement slurry according to any one of claims 1 to 4, further comprising a second flow path to be transferred. The cement slurry discharging device according to claim 7, wherein the volume of the first container is 0.01 to 1 L. The discharge device of the cement slurry according to claim 1, further comprising a drive mechanism that moves the discharge port in a horizontal direction and a vertical direction.

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