JP2017185537A - Kneading mechanism, molding device and manufacturing method of foam mixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a kneading mechanism, a molding device and a manufacturing method of a foam mixture capable of shortening time up to providing the foam mixture excellent in fluidity.SOLUTION: A plurality of air supply ports 70 are formed in an agitation blade 24 for agitating a particulate aggregate and an additive in an agitation tank 20. An air supply mechanism 64 comprises a humidification mechanism 72 in an air flow passage 68, and air humidified by the humidification mechanism 72 is supplied in the agitation tank 20 from the air supply ports 70. The air supply ports 70 are formed in a part facing to the frame inside of a frame body 24A of the agitation blade 24.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a kneading mechanism, a molding apparatus, and a method for producing a foamed mixture.

  There is a method of obtaining a foamed mixture by putting a particulate aggregate, a water-soluble binder and water in a stirring tank and stirring them (for example, see Patent Document 1).

Japanese Patent No. 4428385 JP2013-180300A

  However, in such a technique, it takes a relatively long time to obtain a foam mixture having good fluidity. In addition, there is a technology that attempts to promote sand agitation by blowing air from a push rod inserted into a filling nozzle of the agitation tank (see, for example, Reference 2). Is limited by the position and number of the filling nozzles and contributes only to the stirring of the sand in the vicinity of the filling nozzles.

  In view of the above facts, an object of the present invention is to obtain a kneading mechanism, a molding apparatus, and a method for producing a foamed mixture that can shorten the time required to obtain a foamed mixture having good fluidity.

  The kneading mechanism according to the first aspect of the present invention includes a stirring tank for storing the particulate aggregate and the additive, a stirring blade for stirring the particulate aggregate and the additive in the stirring tank, and the stirring blade. And an air supply mechanism capable of supplying air from the air supply port into the agitation tank.

  According to the said structure, the particulate aggregate and additive stored in the stirring tank are stirred by the stirring blade. Here, an air supply port is formed in the stirring blade, and the air supply mechanism can supply air from the air supply port into the stirring tank. Then, when air is supplied into the agitation tank from the air supply port while the particulate aggregate and additive are being agitated by the agitating blade, air is efficiently included in the particulate aggregate and additive. Therefore, compared with the case where air is not supplied from a stirring blade, a foaming mixture with good fluidity can be obtained with short stirring.

  A kneading mechanism according to a second aspect of the present invention is the kneading mechanism according to the first aspect, wherein the air flow path of the air supply mechanism is provided with a humidifying mechanism for humidifying the air supplied into the agitation tank. ing.

  According to the said structure, the humidification mechanism provided in the air flow path of the air supply mechanism humidifies the air supplied in a stirring tank. Then, when the air is supplied from the air supply port into the stirring tank while the particulate aggregate and the additive are being stirred by the stirring blade, the mixture of the particulate aggregate and the additive is added to the air. Moisture will be supplied. For this reason, for example, even in an environment where the initial moisture ratio of the mixture in the stirring tank is suppressed and the mixture being stirred is easily dried, the drying of the mixture is suppressed without replenishing water separately. Therefore, foaming proceeds stably.

  A kneading mechanism according to a third aspect of the present invention is the kneading mechanism according to the first or second aspect, wherein the stirring blade is attached to the frame body having a hollow cross section and the frame body. And an air supply port formed at a portion of the frame that faces the inner side of the frame.

  According to the above configuration, since the stirring blade includes the frame body and the net portion disposed inside the frame, at the time of stirring, the mixture of the particulate aggregate passing through the frame inside of the frame body and the additive is added. Air can be included in the mixture by being finely divided by the net. Here, since the air supply port is formed at the part facing the inner side of the frame having a hollow cross-section, air is blown into the mixture that passes through the inner side of the frame, so that the mixture being stirred Air can be contained more efficiently.

  According to a fourth aspect of the present invention, there is provided a kneading mechanism according to the first or second aspect, wherein the stirring blade is a frame having a hollow cross section attached to a rotating shaft that rotates in a predetermined rotational direction. And a net portion that is attached to the frame body and disposed inside the frame body, and the frame body has a side opposite to a side on which the frame body rotates when the rotation shaft rotates. The air supply port is formed at a portion facing the surface.

  According to the above configuration, since the stirring blade includes the frame body and the net portion disposed inside the frame, at the time of stirring, the mixture of the particulate aggregate passing through the frame inside of the frame body and the additive is added. Air can be included in the mixture by being finely divided by the net. Here, the frame having a hollow cross-section is attached to a rotating shaft that rotates in a predetermined rotation direction, and the frame has a portion that faces away from the side on which the frame rotates when the rotating shaft rotates. An air supply port is formed. For this reason, at the time of stirring by the stirring blade, turbulent flow is generated in a region opposite to the side on which the frame body rotates and air is blown into the region where such turbulent flow is generated. Air can be efficiently contained.

  A kneading mechanism according to a fifth aspect of the present invention is the kneading mechanism according to any one of the first to fourth aspects, wherein the axis is set along the vertical direction and the stirring blade is attached to the lower end. A rotating shaft that is rotatably arranged about its own axis, a tube that passes through the inside of the rotating shaft and distributes air supplied from the air supply port into the stirring tank, and an upper end of the rotating shaft And a joint portion connected to the rotary shaft via a bearing disposed on the outer peripheral side of the upper end portion of the rotary shaft, and the tube is disposed at a lower portion and a side of the joint portion. It arrange | positions in the state which penetrated the said joint part through the part, and is supported by the side part of the said joint part.

  According to the said structure, the rotating shaft with which the stirring blade was attached to the lower end part is arrange | positioned so that rotation around the own axis line is possible, and the joint part which covers the upper end part of a rotating shaft from upper direction is the upper end of a rotating shaft. It is connected to the rotating shaft via a bearing arranged on the outer peripheral side of the part. For this reason, even if the rotating shaft rotates around its own axis, the joint portion does not rotate. In addition, the tube that circulates the air supplied from the air supply port into the agitation tank passes through the inside of the rotating shaft, but the tube passes through the joint part through the lower part and the side part of the joint part. Since it is supported by the side part of the joint part, the position where the joint part supports the tube is maintained even if the tube rotates together with the rotating shaft. Thereby, it can prevent that a tube becomes entangled at the time of rotation of a rotating shaft.

  A kneading mechanism according to a sixth aspect of the present invention is the configuration according to any one of the first to fifth aspects, wherein a pressure sensor is disposed in the air flow passage of the air supply mechanism.

  According to the above configuration, when the air supply port is clogged, the detected value of the pressure sensor becomes higher than when the air supply port is not clogged. Can be detected.

  A kneading mechanism according to a seventh aspect of the present invention is the configuration according to any one of the first to sixth aspects, wherein the diameter of the air supply port is set to 0.1 mm to 0.3 mm. .

  According to the above configuration, the pressure loss can be suppressed by making the diameter of the air supply port 0.1 mm or more, and the air can be blown out favorably, and the diameter of the air supply port is 0.3 mm or less. Thus, it is possible to prevent or suppress the particulate aggregate from entering the air flow passage from the air supply port when the stirring blade is moved upward from the stirring tank after stirring.

  The molding apparatus of the present invention described in claim 8 is a mold in which a mold molding space is formed by one mold and the other mold, and a filling port is formed through an upper wall portion disposed on the upper side. A filling port penetratingly formed at the bottom of the stirring tank, the stirring tank being capable of stirring the particulate aggregate and additive in the stirring tank by the stirring blade, and the filling port The kneading mechanism according to any one of claims 1 to 7, wherein the kneading mechanism is disposed so as to be movable between the second position which is directly above the filling port and the first position. A filling port closing mechanism that closes the filling port of the stirring tank in a state; a material supply unit that supplies particulate aggregate and additive to the stirring tank disposed in the first position; and the second A pressing mechanism that presses the contents of the agitation tank in a state of being placed at a position from above.

  According to the above configuration, in the state where the agitation tank is disposed at the first position, the filling port at the bottom of the agitation tank is closed by the filling port closing mechanism, and the particulate aggregate and additive are supplied from the material supply unit to the agitation tank. Supplied. Then, when air is supplied from the air supply port into the stirring tank while the particulate aggregate and the additive in the stirring tank are stirred by the stirring blade, the particulate aggregate and the additive are efficiently contained. Air can be contained in the foamed mixture, and a foamed mixture having good fluidity can be obtained by stirring for a short time. On the other hand, in the state where the stirring tank is disposed at the second position where the filling port of the stirring tank is directly above the filling port of the upper wall portion of the mold, the foamed mixture as the contents of the stirring tank is moved upward by the pressing mechanism. Is pressed from. Thereby, after passing through the filling port and the filling port, the foamed mixture is filled into a mold making space formed by one mold and the other mold and solidified to form a mold.

  According to a ninth aspect of the present invention, there is provided a method for producing a foamed mixture of the present invention, a stirring tank, a stirring blade that stirs the contents of the stirring tank, and an air supply port formed in the stirring blade. An air supply mechanism capable of supplying air into a stirring tank, and a method for producing a foamed mixture, wherein the particulate aggregate, the water-soluble binder, the foaming agent and water are contained in the stirring tank. Air is supplied from the air supply port into the agitation tank by the air supply mechanism while being agitated by the agitation blades.

  According to the above configuration, the particulate aggregate, the water-soluble binder, the foaming agent, and water are stirred in the stirring tank by the air supply mechanism from the air supply port formed in the stirring blade. Supply air to As a result, air can be efficiently contained in the mixture of the particulate aggregate, the water-soluble binder, the foaming agent and the water, so that the stirring can be performed in a short time compared to the case where the air is not supplied from the stirring blade. A foam mixture having good fluidity can be obtained.

  A method for producing a foamed mixture according to a tenth aspect of the present invention is the method according to the ninth aspect, wherein the air supply mechanism humidifies the air and then sends the air from the air supply port into the stirring tank. To supply.

  According to the above configuration, humidified air is supplied from the air supply port into the stirring tank. For this reason, for example, even in an environment where the initial moisture ratio of the mixture in the stirring tank is suppressed and the mixture being stirred is easily dried, the drying of the mixture is suppressed without replenishing water separately. Therefore, foaming proceeds stably.

  As described above, according to the present invention, there is an excellent effect that the time required to obtain a foamed mixture having good fluidity can be shortened.

It is a schematic front view which shows the molding apparatus which concerns on one Embodiment of this invention. It is a schematic block diagram which shows typically a part of kneading | mixing mechanism which is a part of molding apparatus of FIG. It is a schematic block diagram which shows a kinematic viscosity measuring apparatus by a front view. It is a graph which shows the result of having extracted sand during kneading and measuring it. FIG. 4A shows the result of kinematic viscosity measurement. FIG. 4B shows the result of moisture measurement. It is a figure which shows the flow of experiment. It is a figure which shows the principal part of a modification. FIG. 6A shows a front view. FIG. 6B is a schematic plan view of the frame.

  A molding apparatus equipped with a kneading mechanism according to an embodiment of the present invention and a method for producing a foamed mixture will be described with reference to FIGS. FIG. 1 shows a schematic front view of a molding apparatus 10 according to the present embodiment.

(Overall configuration of molding equipment)
First, the overall configuration of the molding apparatus 10 shown in FIG. 1 will be outlined.

  The molding apparatus 10 has a kneading mechanism 12 on the right side of the apparatus. The kneading mechanism 12 includes a stirring tank 20 (also referred to as “kneading tank”) that stores sand and additives as particulate aggregates, and stirs the contents (sand and additives) in the stirring tank 20. A stirring blade 24 (also referred to as “kneading blade”) is provided as a stirring blade. A plurality of filling ports 22 are formed through the bottom 20B of the stirring tank 20 in a container shape, and a filling port closing mechanism 26 that can close the filling port 22 is provided below the stirring tank 20 in the figure. It has been. The kneading mechanism 12 includes a use position (position shown in FIG. 1) where the stirring blade 24 is positioned inside the stirring tank 20, and a retreat position (not shown) where the stirring blade 24 is retracted upward from the inside of the stirring tank 20. , And a kneading blade moving mechanism 28 that moves between them (in the direction of arrow Y).

  The molding apparatus 10 also includes a horizontal movement mechanism 32 for moving the stirring tank 20 of the kneading mechanism 12 along the frame portion 30 extending in the apparatus left-right direction (in the direction of the arrow X). The horizontal movement mechanism 32 is a kneading position as the first position on the lower side of the stirring blade 24 (the same position as the position shown in FIG. 1) with the stirring blade 24 in the retracted position. ) And a filling position (not shown) as a second position on the left side of the apparatus with respect to the kneading position. The kneading position is set to a position where the sand and additives in the stirring tank 20 can be stirred by the stirring blade 24, and both the filling positions are between the mold 40 and the pressing mechanism 16 described later. Set to position.

  The molding apparatus 10 has a mold mechanism 14 on the left side of the apparatus and on the lower side of the apparatus with respect to the kneading mechanism 12. The mold mechanism 14 includes a mold 40 for forming the foamed mixture kneaded by the kneading mechanism 12 into a predetermined shape. Further, a pressing mechanism 16 (filling mechanism) is provided immediately above the mold mechanism 14 and in the upper part of the apparatus. The pressing mechanism 16 presses the foamed mixture, which is the content of the stirring tank 20 in a state where the stirring tank 20 is disposed at the filling position (not shown), from above, and from the filling port 22 of the stirring tank 20. The mold 40 is configured to be filled (injected) with the foamed mixture. Further, a mold extrusion mechanism 18 (upper mold extrusion mechanism) is provided on the left side of the stirring tank 20 on the apparatus upper side with respect to the mold mechanism 14 and on the apparatus lower side with respect to the pressing mechanism 16. The mold extrusion mechanism 18 is a mechanism for taking out the mold from the mold 40 by opening the mold 40 in conjunction with the mold mechanism 14. Further, in this embodiment, the mold extrusion mechanism 18 is connected to the stirring tank 20 via the connecting portion 19 in the apparatus left-right direction, and can be moved together with the stirring tank 20 in the apparatus left-right direction.

(Outline of each mechanism)
Next, each mechanism will be outlined.

  In the mold mechanism 14, the mold 40 forms a mold making space with an upper mold 42 as one mold and a lower mold 44 as the other mold. That is, the mold 40 in the present embodiment is a horizontal split mold. The lower mold 44 is attached to the upper surface of the lifting frame 14A. The elevating frame 14A can be moved up and down along guide rods 14C erected in the vertical direction of the apparatus at the four corners of the machine base 14B, and the piston rod of the cylinder 14D installed upward on the lower side of the elevating frame 14A. 14D1. That is, the elevating frame 14A is raised and lowered according to the expansion and contraction of the piston rod 14D1 of the cylinder 14D. On the other hand, the upper die 42 is disposed immediately above the lower die 44 and is supported by a support mechanism portion 14E attached to the guide rod 14C. Further, a filling port 46 is formed through the upper wall portion 42A of the upper mold 42 (the upper wall portion disposed on the upper side of the mold 40).

  The pressing mechanism 16 provided in the upper part of the apparatus just above the mold mechanism 14 is provided in the ceiling part 30A of the frame part 30 and includes a piston 16A. A plurality of exhaust holes (not shown) are formed through the piston 16A. The piston 16A is connected to the lower end side of the piston rod 16B1 of the downward cylinder 16B, and moves up and down by the operation of the cylinder 16B.

  The mold extrusion mechanism 18 provided on the apparatus left side of the stirring tank 20 on the lower side of the apparatus with respect to the pressing mechanism 16 includes a mold extrusion member 18A. A plurality of mold extruding pins are formed in the mold extruding member 18A, and these mold extruding pins can be inserted into a filling port 46 formed in the upper mold 42. The mold extruding member 18A is connected to the lower end side of the piston rod 18B1 of the downward cylinder 18B, and moves up and down by the operation of the cylinder 18B.

  A horizontal movement mechanism 32 for moving the agitation tank 20 and the mold pushing mechanism 18 in the left-right direction of the apparatus includes a guide part 32A extending in the left-right direction of the apparatus in the frame part 30, and a traveling carriage capable of traveling along the guide part 32A. (Not shown). That is, the horizontal movement mechanism 32 moves the stirring tank 20 and the mold extrusion mechanism 18 as the traveling carriage travels (moves) along the guide portion 32A. In addition, the frame part 30 is being fixed to the upper end part of the guide rod 14C mentioned above. Further, the filling position (not shown) of the stirring tank 20 is a position where the filling port 22 of the stirring tank 20 is directly above the filling port 46 of the upper mold 42. Further, in the drawing, a state where the mold pushing mechanism 18 is disposed at a position retracted from right above the mold 40 to the left side of the apparatus is indicated by a two-dot chain line.

  The kneading mechanism 12 includes the stirring tank 20 as described above. The agitation tank 20 includes a cylindrical portion 20A having the vertical direction as the central axis direction, and a bottom portion 20B that is fixed to the lower end of the cylindrical portion 20A and closes the lower end side opening of the cylindrical portion 20A. In the present embodiment, the volume of the stirring tank 20 is set to be considerably larger than the volume of the mold making space of the mold 40. Further, a lid 48 can be disposed in the upper end side opening of the cylindrical portion 20A.

  In addition, the kneading mechanism 12 includes a kneading blade operating mechanism 50 for operating the stirring blade 24 on the ceiling portion 30 </ b> A side of the frame portion 30. The kneading blade operating mechanism 50 includes a rotating shaft 52 for rotating the stirring blade 24. The rotating shaft 52 is disposed so as to be rotatable about its own axis, and the output shaft of the motor 50M is provided via the driving force transmitting portion 50B. It is the composition connected to. That is, the kneading mechanism 12 moves the contents of the stirring tank 20 by operating the motor 50M in a state where the stirring tank 20 is disposed at the kneading position (the same position as the position of the stirring tank 20 shown in FIG. 1). The stirring blade 24 is kneaded. Note that the axis of the rotation shaft 52 is set along the vertical direction. The rotating shaft 52 includes a blade-side rotating shaft 52C connected to the stirring blade 24, a driving-side rotating shaft 52A that receives the driving force transmitted by the driving force transmitting unit 50B, a blade-side rotating shaft 52C, and a driving-side rotating shaft 52A. And a connecting portion 52B for connecting the two.

  The kneading blade moving mechanism 28 includes a downward-facing cylinder 28A and a lifting platform 28B that moves up and down according to the operation of the cylinder 28A. The elevator base 28B rotatably supports the drive-side rotary shaft 52A via the bearing portion 28C, and supports the lid 48 and the motor 50M via other members. Accordingly, the stirring blade 24, the lid 48, and the motor 50M are moved up and down in accordance with the operation of the cylinder 28A.

  The filling port closing mechanism 26 provided on the lower side of the kneading blade operating mechanism 50 is provided with the same number of stop pins 26A (plugs) as the number of filling ports 22 for closing the filling port 22 of the bottom 20B of the stirring tank 20. ing. The retaining pin 26A protrudes upward from the horizontally disposed base plate 26B. The base plate 26B is attached to the upper end of the piston rod 26C1 of the upward cylinder 26C, and moves up and down by the operation of the cylinder 26C. The filling port closing mechanism 26 stops the filling port 22 of the stirring tank 20 in a state where the stirring tank 20 is disposed at the kneading position (the same position as the position of the stirring tank 20 shown in FIG. 1). It is possible to close with. Note that the cylinder 26C of the filling port closing mechanism 26 is supported by the frame portion 30 via a member.

(Detailed explanation of kneading mechanism)
Next, the kneading mechanism 12 will be further described with reference to FIG. FIG. 2 shows a part of the kneading mechanism 12 in a schematic schematic configuration diagram.

  As shown in FIG. 2, the kneading mechanism 12 has sand and additives (water-soluble) in the stirring tank 20 in a state where the stirring tank 20 is disposed at the kneading position (position of the stirring tank 20 shown in FIG. 2). A material supply unit 54 for supplying a binder, a foaming agent, and water) is provided. The material supply unit 54 includes a sand supply unit 56, a binder supply unit 58, a foaming agent supply unit 60, and a water supply unit 62.

  The sand supply unit 56 includes a sand supply device 56A (blocked and illustrated) capable of storing sand and supplying sand, and a sand throwing chute 56B that receives the sand supplied by the sand supply device 56A. The sand supply device 56A includes an open / close gate (not shown) so that the amount of sand supplied can be adjusted. Further, the sand throwing chute 56 </ b> B is inclined, and the lower end portion thereof is disposed inside the upper end opening portion of the stirring tank 20.

  For example, dredged sand, alumina sand, olivine sand, chromite sand, zircon sand, mullite sand, and other artificial sand (so-called artificial aggregate) can be applied to the sand as the particulate aggregate. .

  The binder supply unit 58 includes a binder supply device 58A (blocked and illustrated) that stores the water-soluble binder and supplies the water-soluble binder with a pump, and includes a binder flow passage 58B connected to the binder supply device 58A. Further, a valve device 58 </ b> C attached to the downstream end of the binder flow passage 58 </ b> B is installed in the lid 48 in the binder supply unit 58. The valve device 58C includes a valve (not shown) for opening and closing the downstream passage of the binder flow passage 58B, and an opening / closing mechanism (not shown) for opening and closing the valve. A supply port 58 </ b> D constituting the downstream end portion of the binder supply unit 58 is disposed on the upper side of the stirring tank 20 and is directed to the inside of the stirring tank 20.

  The foaming agent supply unit 60 includes a foaming agent supply device 60A (blocked and illustrated) that stores the liquid foaming agent and supplies the foaming agent with a pump, and is connected to the foaming agent supply device 60A. 60B is provided. In the present embodiment, a surfactant is added to the liquid foaming agent stored in the foaming agent supply device 60A. Further, the foaming agent supply section 60 is provided with a valve device 60C attached to the downstream end of the foaming agent flow passage 60B. The valve device 60C includes a valve (not shown) for opening and closing the downstream passage of the foaming agent flow passage 60B, and an opening / closing mechanism (not shown) for opening and closing the valve. A supply port 60 </ b> D constituting the downstream end portion of the foaming agent supply unit 60 is disposed on the upper side of the stirring tank 20 and is directed to the inside of the stirring tank 20.

  The water supply unit 62 includes a water supply device 62A (blocked and illustrated) that stores water and supplies water with a pump, and also includes a water flow passage 62B connected to the water supply device 62A. In the water supply unit 62, a valve device 62C attached to the downstream end of the water flow passage 62B is installed on the lid 48. The valve device 62C includes a valve (not shown) for opening and closing the downstream passage of the water passage 62B, and an opening / closing mechanism (not shown) for opening and closing the valve. A supply port 62 </ b> D constituting the downstream end of the water supply unit 62 is disposed on the upper side of the stirring tank 20 and is directed to the inside of the stirring tank 20.

  On the other hand, the stirring blade 24 is attached to the lower end portion of the rotating shaft 52, that is, the lower end portion of the blade-side rotating shaft 52C, and includes a frame body 24A having a hollow cross section and a rectangular frame shape, and attached to the frame body 24A. A net 24B is provided inside the frame 24A. The mesh portion 24B of the stirring blade 24 is provided in the entire region inside the frame of the frame body 24A, and is formed of a wire and has a lattice-like coarse mesh. Further, the frame body 24A of the stirring blade 24 includes an upper frame portion 24A1 that constitutes an upper portion thereof and extends in the lateral direction, a lower frame portion 24A2 that is disposed in parallel with the upper frame portion 24A1, an upper frame portion 24A1, and a lower frame portion 24A1. A pair of side frame portions 24A3 arranged in parallel with each other by connecting the frame portions 24A2. The upper frame portion 24A1, the lower frame portion 24A2, and the side frame portion 24A3 have a rectangular cross-sectional shape that is orthogonal to each axis.

  A plurality of (for example, a total of 20) air supply ports 70 are formed in a portion 24I of the stirring blade 24 facing the inner side of the frame body 24A, as shown in the partially enlarged view. In the present embodiment, as an example, the air supply port 70 is set at a portion on both sides of the lower frame portion 24A2 and a lower portion of the side frame portion 24A3. The diameter of the air supply port 70 is set to 0.1 mm to 0.3 mm. These air supply ports 70 constitute a part of the air supply mechanism 64.

  The air supply mechanism 64 includes a compressor 66 (illustrated in a block form) shown at the right end in the drawing for supplying air, and is connected to the compressor 66 so as to circulate air from a connection portion with the compressor 66 to the air supply port 70. Air flow passage 68 is provided. Thereby, the air supply mechanism 64 can supply air from the air supply port 70 into the stirring tank 20. In addition, the pressure of the air supplied in the stirring tank 20 shall be 0.1 MPa-0.5 MPa as an example in this embodiment. The air flow path 68 of the air supply mechanism 64 connects the first tube 74 that connects the compressor 66 and the water tank 76, the water tank 76, the water tank 76, and the frame body 24 </ b> A and passes through the inside of the rotary shaft 52. The two tubes 78 and the frame body 24A are formed.

  Water 90 is stored in the water tank 76, the downstream end of the first tube 74 is disposed in the water 90, and the upstream end of the second tube 78 is the top plate portion 76 </ b> A ( That is, it is disposed above the water 90). With the arrangement configuration of the first tube 74, the water tank 76, and the second tube 78, the air supplied into the agitation tank 20 is humidified (humidification by water aeration). In other words, the air flow path 68 of the air supply mechanism 64 is provided with a humidifying mechanism 72 including a water tank 76. In addition, the humidity of the air supplied in the stirring tank 20 is 50%-100% as an example in this embodiment.

  The second tube 78 is attached to the joint portion 92 on the upper side of the drive side rotation shaft 52A. The joint portion 92 covers the upper end portion of the rotating shaft 52, that is, the upper end portion of the driving side rotating shaft 52A from the upper side, and, as shown in the enlarged partial view, the upper end portion of the driving side rotating shaft 52A (the rotating shaft 52). It is connected to the drive side rotating shaft 52A (rotating shaft 52) via a bearing 94 disposed on the outer peripheral side. Thereby, even if the rotating shaft 52 rotates, the joint part 92 does not rotate. The second tube 78 is arranged in a state of passing through the joint portion 92 through the lower hole portion and the side hole portion of the joint portion 92 and supported by the side portion of the joint portion 92.

  Further, a valve device 96 is disposed in the air flow passage 68 (passage formed by the first tube 74 as an example in the present embodiment). The valve device 96 includes a valve (not shown) for opening and closing a predetermined part of the air flow passage 68 and an opening / closing mechanism (not shown) for opening and closing the valve. Further, a pressure sensor 98 is disposed in the air flow passage 68 (passage formed by the second tube 78 as an example in the present embodiment). The pressure sensor 98 measures the pressure in a predetermined space in the air flow path 68.

(Mold molding)
Next, an outline of molding of a sand mold (sand core) by the molding apparatus 10 (see FIG. 1) of the present embodiment will be outlined.

  First, the agitation tank 20 is arranged at the kneading position (position shown in FIG. 2), and the filling port 22 of the bottom 20B of the agitation tank 20 is closed by the stop pin 26A of the filling port closing mechanism 26 (see FIG. 1). . Sand, a water-soluble binder, a foaming agent, and water are respectively supplied from the material supply unit 54 to the stirring tank 20 disposed in the kneading position (position shown in FIG. 2). Then, while the mixture a (sand, water-soluble binder, foaming agent and water) in the stirring tank 20 is stirred by the stirring blade 24, air is supplied from the air supply port 70 into the stirring tank 20 by the air supply mechanism 64. Is done. Thereby, a foaming mixture is obtained.

  On the other hand, in the mold 40 shown in FIG. 1, the upper mold 42 and the lower mold 44 are combined and arranged at a predetermined height position (not shown) by raising the lower mold 44 by the operation of the cylinder 14D. Further, it is heated to about 250 ° C.

  On the other hand, as for the stirring tank 20, the stop pin 26A is pulled out from the filling port 22 of the bottom part 20B. Further, the stirring blade 24 is retracted upward from the inside of the stirring tank 20 by the kneading blade moving mechanism 28 and the lid 48 is also retracted upward. Next, the stirring tank 20 and the mold pushing mechanism 18 are slid to the left in the figure by the horizontal movement mechanism 32, and the filling port 22 of the stirring tank 20 is directly above the filling port 46 of the upper wall portion 42A of the upper mold 42. The stirring tank 20 is arranged at a position (filling position).

  In this state, when the foaming mixture as the contents of the stirring tank 20 is pressed from above by the piston 16A of the pressing mechanism 16, the foaming mixture passes through the filling port 22 of the stirring tank 20 and the filling port 46 of the upper mold 42. After passing through, the mold making space formed by the upper mold 42 and the lower mold 44 is filled (pressed and injected). Then, the foamed mixture is dried and solidified by the heat of the heated mold 40, and the mold is formed.

  Next, the stirring tank 20 and the mold extrusion mechanism 18 are slid to the right side in the drawing by the horizontal movement mechanism 32, the stirring tank 20 is returned to the kneading position, and the mold extrusion mechanism 18 is disposed immediately above the upper mold 42. Is done. In the stirring tank 20 returned to the kneading position, as shown in FIG. 2, a stop pin 26A is inserted into the filling port 22 of the bottom 20B, and sand, a water-soluble binder, a foaming agent, water, and water are supplied from the material supply unit 54. Are additionally supplied (supplemented). Then, while the mixture a in the agitation tank 20 is agitated by the agitation blade 24, air is supplied from the air supply port 70 into the agitation tank 20 by the air supply mechanism 64 to produce a foam mixture for the next mold making. The On the other hand, in the filling port 46 of the upper mold 42 shown in FIG. 1, the mold formed by inserting the mold extruding pin of the mold extruding member 18 </ b> A of the mold extruding mechanism 18 and lowering the lower mold 44. Is taken out.

(Production method of foaming mixture and action / effect of kneading mechanism)
Next, the method for producing the foamed mixture will be described with reference to FIG. 2, and the operation and effect of the kneading mechanism 12 will be described.

  In the method for producing a foamed mixture according to the present embodiment, sand, a water-soluble binder, a foaming agent, and water are stirred in the stirring tank 20 by the air supply mechanism 64 from the air supply port 70 in the stirring tank 20. Supply air to Thereby, air can be efficiently contained in the mixture a of sand, water-soluble binder, foaming agent and water, and air can be uniformly dispersed by the rotation of the stirring blade 24. Therefore, in the case of this embodiment, compared with the case where air is not supplied from the stirring blade 24, the foaming mixture with favorable fluidity | liquidity can be obtained by stirring for a short time.

  Further, in the kneading mechanism 12 of the present embodiment, the stirring blade 24 includes the frame body 24A and the net portion 24B disposed inside the frame, so that during stirring, the stirring blade 24 passes through the inside of the frame body 24A. The mixture a can be finely divided by the mesh portion 24B so that air is included in the mixture a. Here, since the air supply port 70 is formed at a portion facing the inner side of the frame body 24A having a hollow cross section, air is blown into the mixture a that passes through the inner side of the frame body 24A. Air can be more efficiently contained in the mixture a.

  In the present embodiment, the air supply mechanism 64 humidifies the air with the humidification mechanism 72 and then supplies the air from the air supply port 70 into the agitation tank 20. For this reason, for example, even in an environment where the initial moisture ratio of the mixture a in the stirring tank 20 is suppressed and the mixture a being stirred is easily dried, the mixture a is not replenished. Therefore, foaming proceeds stably.

  FIG. 4 shows the results of kinematic viscosity measurement when humidified air is supplied from the air supply port into the stirring tank and when non-humidified air is supplied from the air supply port into the stirring tank. 4 (A)) and a graph comparing water measurement results (FIG. 4B) are shown. 4 (A) and 4 (B), the horizontal axis indicates how many times the additional kneading is performed (details will be described later), and the vertical axis in FIG. 4 (A) indicates kinematic viscosity measurement. The vertical axis of FIG. 4B shows the result of moisture measurement. In addition, 0 on the horizontal axis indicates extraction after the initial kneading (described later). In the graph of FIG. 4A, a white triangle mark indicates a case where air humidified to 100% humidity is supplied, and a white circle mark indicates a case where air which is not humidified is supplied. In the graph of FIG. 4B, a black triangle indicates a case where air humidified to 100% humidity is supplied, and a black circle indicates a case where air which is not humidified is supplied.

  The experimental method whose measurement results are shown in FIG. 4 will be described. First, the flow of the experiment will be described with reference to FIG. In this experiment, first, about 5 kg (details will be described later) of materials (sand, water-soluble binder, foaming agent and water) are charged (S1), and initial kneading (stirring) is performed for 420 seconds (S2). Next, 3.1 kg of a mixture composed of sand or the like is extracted (S3), and kinematic viscosity measurement and moisture measurement are performed on the extracted mixture (S4). The kinematic viscosity measurement will be described later. Next, 3.1 kg of a mixture composed of sand or the like (that is, sand, water-soluble binder, foaming agent and water) is replenished (S5), and additional kneading (stirring) is performed for 45 seconds (S6). Thereafter, the process returns to S3, and S3 to S6 are repeated five times.

  In this experiment, ESPAR # 90 (manufactured by Yamakawa Sangyo Co., Ltd.) is used as sand, No. 3 water glass is used as a water-soluble binder, and Adeka Hope YES-25 (manufactured by ADEKA Co., Ltd.) is applied as a foaming agent. The initial input amount of sand is 5 kg. The water-soluble binder is supplied at 0.65 wt% with respect to the sand, the foaming agent is supplied at 0.03 wt% with respect to the sand, and the water is supplied at 3.20 wt% with respect to the sand. The air flow rate of air supplied from the air supply port is 8 L / min. In addition, in the case of humidifying air, two water tanks having a water volume of 5 L (a tank corresponding to the water tank 76 in FIG. 2) are provided in the air flow passage, and the air passing through these two water tanks (in other words, The air passed through the water tank twice) was supplied from the air supply port. In addition, the external temperature at the time of this experiment is 6-8 degreeC, and humidity is 23%.

  Next, a method for measuring kinematic viscosity will be outlined with reference to FIG. FIG. 3 shows a measuring device 80 used for kinematic viscosity measurement.

  The measuring device 80 includes a cylindrical member 82 disposed so that the central axis is in the vertical direction with an inner diameter of 50 mm, and a columnar weight 84 that pushes the measurement target mixture b placed in the cylindrical member 82 from above. And a base plate 86 that is horizontally disposed to support the lower end opening 82A of the cylindrical member 82. The base plate 86 is formed with a small-diameter hole portion 86 </ b> A at a portion corresponding to the central portion of the lower end opening portion 82 </ b> A of the cylindrical member 82.

  At the time of measurement, the mixture b is put in the cylindrical member 82, and thereafter, a weight 84 is placed on the mixture b, and the mixture b is pushed from above by the weight 84. Then, it is measured how many seconds the mixture b passes between the two upper and lower points set in advance in the cylindrical member 82.

  As shown in FIG. 4B, when non-humidified air was supplied from the air supply port into the agitation tank (in the case of a black circle), the water ratio (%) in the mixture gradually decreased. . On the other hand, when 100% humidified air is supplied from the air supply port into the stirring tank (in the case of a black triangle), the water ratio (%) in the mixture is 2.90%. It was within the range of plus or minus 0.05%.

  In addition, as shown in FIG. 4A, when non-humidified air is supplied from the air supply port into the agitation tank (in the case of a white circle), the kinematic viscosity measurement value is obtained each time the number of times is increased. Tended to gradually increase (kneading state gradually deteriorated). On the other hand, when 100% humidified air is supplied from the air supply port into the stirring tank (in the case of white triangles), the measured value of kinematic viscosity is stable (kneading state) Is stable).

  Returning to FIG. 2, the operation and effect of the kneading mechanism 12 will be described. In the present embodiment, the rotating shaft 52 having the stirring blade 24 attached to the lower end portion is disposed so as to be rotatable around its own axis, and rotates. The joint portion 92 that covers the upper end portion of the shaft 52 from above is connected to the rotating shaft 52 via a bearing 94 disposed on the outer peripheral side of the upper end portion of the rotating shaft 52. For this reason, even if the rotating shaft 52 rotates around its own axis, the joint portion 92 does not rotate. The second tube 78 for circulating the air supplied from the air supply port 70 into the stirring tank 20 passes through the inside of the rotating shaft 52, but the second tube 78 passes through the lower part and the side part of the joint part 92. Therefore, even if the second tube 78 rotates with the rotating shaft 52, the joint portion 92 supports the second tube 78 even if the second tube 78 rotates together with the rotating shaft 52. Is maintained. Thereby, it is possible to prevent the second tube 78 from being entangled when the rotation shaft 52 rotates.

  In the present embodiment, a pressure sensor 98 is disposed in the air flow path 68 of the air supply mechanism 64. For this reason, when the air supply port 70 is clogged, the detection value of the pressure sensor 98 is higher than when the air supply port 70 is not clogged. Can be detected automatically.

  In the present embodiment, the diameter of the air supply port 70 is set to 0.1 mm to 0.3 mm. By reducing the diameter of the air supply port 70 to 0.1 mm or more, pressure loss can be suppressed and air can be blown out well, and by setting the diameter of the air supply port 70 to 0.3 mm or less. It is possible to prevent or suppress sand from entering the air flow path 68 from the air supply port 70 when the stirring blade 24 is moved upward from the stirring tank 20 after stirring.

  As described above, according to the present embodiment, the time required to obtain a foamed mixture having good fluidity can be shortened.

(Modification of the embodiment)
Next, a modification of the above embodiment will be described with reference to FIG. The principal part of the modification of the said embodiment is shown by FIG. FIG. 6A shows a front view of the main part of the modification, and FIG. 6B shows a schematic plan view of the frame. As shown in these drawings, this modified example is different from the above-described embodiment in that a frame body 100A is provided instead of the frame body 24A (see FIG. 2) of the above-described embodiment. Other configurations are the same as those in the above embodiment. In addition, about the component similar to the said embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The stirring blade 100 as the stirring blade shown in FIG. 6 (A) and FIG. 6 (B) is the above embodiment except that the frame body 100A is provided instead of the frame body 24A (see FIG. 2) of the above embodiment. The configuration is the same as that of the stirring blade 24. The frame 100A is attached to the lower end of the rotating shaft 52 that rotates in a predetermined rotation direction (see the arrow 52R in FIG. 6B), that is, the lower end of the blade-side rotating shaft 52C, and has a hollow cross section and a rectangular frame shape. Is formed. As shown in FIG. 6A, the frame body 100A includes an upper frame portion 100A1, a lower frame portion 100A2, and a pair of side frame portions 100A3, similarly to the frame body 24A (see FIG. 2) of the above embodiment. The upper frame portion 100A1, the lower frame portion 100A2, and the side frame portion 100A3 have a rectangular cross-sectional shape orthogonal to each axis. A mesh portion 24B is attached to the frame body 100A in the same manner as the frame body 24A (see FIG. 2) of the above embodiment.

  As shown in FIGS. 6A and 6B, the frame 100A has a side on which the frame 100A rotates when the rotary shaft 52 rotates (see an arrow 100R in FIG. 6B). A plurality of air supply ports 102 are formed in a portion facing the opposite side. In other words, the air supply port 102 is formed so that air blows out on the opposite side to the rotation direction 52R of the rotation shaft 52 (see FIG. 6B). In FIG. 6B, the direction of air blowing from the air supply port 102 is indicated by an arrow 102B. In the present embodiment, as an example, the air supply port 102 is set in a portion on both sides of the pair of side frame portions 100A3 and the lower frame portion 100A2 shown in FIG. The diameter of the air supply port 102 is set similarly to the diameter of the air supply port 70 (see FIG. 2) of the above embodiment.

  According to this modification, substantially the same operations and effects as those of the first embodiment described above can be obtained. Further, in this modified example, during stirring by the stirring blade 100, a turbulent flow is generated in a region opposite to the side on which the frame body 100A shown in FIG. Since air is blown into a region where turbulent flow is generated, air can be more efficiently contained in the mixture a (see FIG. 6A).

(Supplementary explanation of the embodiment)
In the above-described embodiment, the air flow path 68 of the air supply mechanism 64 shown in FIG. 2 is provided with a humidifying mechanism 72 that humidifies the air supplied into the stirring tank 20. The air is supplied from the air supply port 70 into the stirring tank 20 after being humidified, for example, when the kneading mechanism operates in a humid environment or when the lid of the stirring tank is highly sealed, Alternatively, the air supply mechanism does not have to be equipped with a humidifying mechanism and is not humidified when water is replenished during stirring or when the initial moisture ratio of the mixture in the stirring tank is set high. May be fed into a stirred tank.

  In addition, the method of humidifying the air supplied into the stirring tank may be a method other than the above-described embodiment, such as heating evaporation diffusing, ultrasonic humidification, water spraying, or the like.

  In the above-described embodiment, the stirring blades 24 and 100 as the stirring blades are provided with the frame bodies 24A and 100A and the mesh portion 24B. However, the stirring blades may be other types such as a propeller type stirring blade. The stirring blade may be used.

  Moreover, in the said embodiment, although the pressure sensor 98 is arrange | positioned in the air flow path 68, the structure which arrange | positions a flow meter instead of a pressure sensor may be sufficient. By arranging the flow meter, the clogged state of the air supply port can be detected as in the pressure sensor. Moreover, although these structures are preferable, the structure which neither a pressure sensor nor a flow meter arrange | positions to an air flow path can be taken.

  Moreover, in the said embodiment, the diameter of the air supply ports 70 and 102 is set to 0.1 mm-0.3 mm, and such a structure is preferable, but the diameter of an air supply port is not necessarily limited to said setting. It is not something. That is, the diameter and number of air supply ports can be appropriately set depending on the particle diameter of sand, the amount of sand particles, the type of binder, and the like.

  Moreover, in the said embodiment, although the metal mold | die 40 shown by FIG. 1 is a horizontal split metal mold | die, as a modification of the said embodiment, a metal mold | die is made into a vertical split metal mold | die, and one type | mold is used. The mold may be a mold in which a mold making space is formed by the other mold and a filling port is formed through an upper wall portion disposed on the upper side of the mold.

  In addition, the said embodiment and the above-mentioned some modification can be implemented combining suitably.

  Although an example of the present invention has been described above, the present invention is not limited to the above, and it is needless to say that various modifications can be made without departing from the spirit of the present invention. .

DESCRIPTION OF SYMBOLS 10 Molding apparatus 12 Kneading mechanism 16 Pressing mechanism 20 Stirring tank 22 Filling port 24 Stirring blade (stirring blade)
24A Frame 24B Net 26 Filling port closing mechanism 40 Mold 42 Upper mold (one mold)
42A Upper wall 44 Lower mold (the other mold)
46 Filling port 52 Rotating shaft 54 Material supply unit 64 Air supply mechanism 68 Air flow passage 70 Air supply port 72 Humidification mechanism 78 Second tube (tube)
92 Joint 98 Pressure sensor 100 Stirring blade (stirring blade)
100A Frame 102 Air supply port

Claims (10)

An agitation tank for storing particulate aggregate and additives;
Stirring blades for stirring the particulate aggregate and additives in the stirring tank;
An air supply mechanism in which an air supply port is formed in the stirring blade, and air can be supplied from the air supply port into the stirring tank;
A kneading mechanism.   The kneading mechanism according to claim 1, wherein a humidifying mechanism that humidifies air supplied into the agitation tank is provided in an air flow path of the air supply mechanism.   The stirring blade includes a frame body having a hollow cross section and a net portion attached to the frame body and disposed inside the frame body, and the air at a portion facing the frame inside of the frame body. The kneading mechanism according to claim 1 or 2, wherein a supply port is formed.   The stirring blade includes a frame having a hollow cross-section attached to a rotating shaft that rotates in a predetermined rotation direction, and a net portion that is attached to the frame and disposed inside the frame. The kneading mechanism according to claim 1, wherein the air supply port is formed in a portion of the frame that faces away from the side on which the frame rotates when the rotating shaft rotates. . An axis is set along the vertical direction and the stirring blade is attached to the lower end, and a rotating shaft arranged to be rotatable around its own axis,
A tube through which the air supplied from the air supply port into the stirring tank passes through the inside of the rotating shaft;
Covering the upper end of the rotating shaft from above, and a joint portion connected to the rotating shaft via a bearing disposed on the outer peripheral side of the upper end of the rotating shaft;
Have
The tube according to any one of claims 1 to 4, wherein the tube is disposed in a state of passing through the joint portion through a lower portion and a side portion of the joint portion and supported by the side portion of the joint portion. The kneading mechanism described.   The kneading mechanism according to any one of claims 1 to 5, wherein a pressure sensor is disposed in an air flow path of the air supply mechanism.   The kneading mechanism according to any one of claims 1 to 6, wherein a diameter of the air supply port is set to 0.1 mm to 0.3 mm. A mold having a mold making space formed by one mold and the other mold, and a filling port penetratingly formed in an upper wall portion disposed on the upper side,
A filling port is formed through the bottom of the agitation tank, the agitation tank is capable of agitating the particulate aggregate and additive in the agitation tank by the agitation blade, and the filling port is covered by the cover. The kneading mechanism according to any one of claims 1 to 7, wherein the kneading mechanism is disposed so as to be movable between a second position directly above the filling port,
A filling port closing mechanism for closing the filling port of the stirring tank in a state of being arranged at the first position;
A material supply unit for supplying particulate aggregate and additive to the stirring tank in a state of being arranged at the first position;
A pressing mechanism that presses the contents of the agitation tank in the second position from above,
Molding device having. An agitation tank, an agitation blade for agitating the contents of the agitation tank, an air supply mechanism in which an air supply port is formed in the agitation blade and capable of supplying air from the air supply port into the agitation tank; A method for producing a foamed mixture using
A foam mixture in which air is supplied from the air supply port into the stirring tank by the air supply mechanism while stirring the particulate aggregate, the water-soluble binder, the foaming agent, and water in the stirring tank by the stirring blade. Manufacturing method.   The said air supply mechanism is a manufacturing method of the foaming mixture of Claim 9 which humidifies air and supplies the said air in the said stirring tank from the said air supply port.