JP7545129B2 - Ingot Casting Equipment - Google Patents

Description

The present invention relates to an ingot casting device for casting ingots of precious metals such as gold and silver.

Conventionally, there is known a technique for melting and casting precious metals such as gold and silver (see, for example, Patent Document 1). Patent Document 1 discloses a technique for melting granular precious metal in an environment of an inert gas such as nitrogen or argon, and then cooling and solidifying it into a metal ingot.

Special Publication No. 2014-509948

In the technology described in Patent Document 1, the heating furnace is opened when replacing the mold material, and therefore, after the mold material is heated to melt the precious metal, the furnace must be evacuated and an inert gas must be injected each time the mold material is replaced. In other words, the time required to cast many metal ingots is long, and there is a demand for improved casting efficiency. Therefore, the present disclosure aims to solve the above-mentioned problems.

Below, we explain the means to solve the above problems.

The ingot casting device according to the present invention is an ingot casting device including a chamber having a hollow main body and a lid capable of closing the main body, a turntable provided at the bottom of the chamber, a rotation mechanism for rotating the turntable, a heating mechanism provided in the chamber, and at least one cooling mechanism provided at a location different from the heating mechanism in a plan view, and the turntable is formed with a plurality of placement sections in which mold materials containing metal granules can be placed, and the positions of the plurality of placement sections can be changed by the rotation mechanism rotating the turntable, and the heating mechanism heats one of the mold materials to melt the granules contained in one of the mold materials into molten metal, and the cooling mechanism cools the other mold materials to solidify the molten metal contained in the other mold materials into metal ingots, all at the same time.

In the ingot casting device according to the present invention, the heating mechanism is provided above the turntable in the chamber, and a heating and lifting mechanism is provided below the turntable at the same location as the heating mechanism in a plan view, and it is preferable that the heating process by the heating mechanism is performed in a state in which the heating and lifting mechanism lifts one of the mold materials.

In addition, in the ingot casting device according to the present invention, it is preferable that the heating mechanism includes a heating coil, the mold material is formed of a conductor, and the heating and lifting mechanism lifts one of the mold materials inside the heating coil, and then applies a voltage to the heating coil to inductively heat the one of the mold materials to perform the heat treatment.

In addition, in the ingot casting device according to the present invention, it is preferable that the cooling mechanism is a cooling and lifting mechanism provided below the turntable, and that the cooling process is performed while the cooling and lifting mechanism lifts the other mold materials.

In addition, in the ingot casting device according to the present invention, it is preferable that the cooling lifting mechanism includes a metal cooling plate and a cooling path formed inside the cooling plate, and that the cooling process is performed by circulating cooling water through the cooling path while the cooling lifting mechanism lifts the other mold material via the cooling plate.

In addition, in the ingot casting device according to the present invention, it is preferable that the cooling and lifting mechanism includes an upper cooling section fixed above the cooling plate, and when the cooling and lifting mechanism lifts the other mold material via the cooling plate, the other mold material is sandwiched between the cooling plate and the upper cooling section.

In addition, in the ingot casting device according to the present invention, it is preferable that a cooling passage is formed inside the upper cooling section, and the cooling process is performed by circulating cooling water through the cooling passage while the other mold material is sandwiched between the cooling plate and the upper cooling section.

The ingot casting device of the present invention can cast a large number of metal ingots with a single inert gas injection operation, thereby improving casting efficiency.

In addition, the ingot casting device according to the present invention can suppress the thermal effects on the turntable caused by the mold material heated by the heating mechanism.

In addition, the ingot casting device according to the present invention can suppress the effects of heat from the heating mechanism.

In addition, the ingot casting device according to the present invention can improve the cooling efficiency of the mold material using the cooling mechanism.

In addition, the ingot casting device according to the present invention uses cooling water in the cooling mechanism, which can further improve the cooling efficiency of the mold material.

In addition, with the ingot casting device according to the present invention, the cooling efficiency of the mold material by the cooling mechanism can be improved by sandwiching the other mold material between the cooling plate and the upper cooling section.

In addition, with the ingot casting device according to the present invention, the cooling efficiency of the mold material can be further improved by circulating cooling water through the upper cooling section.

FIG. FIG. FIG. FIG. 4 is a plan view showing a state in which a mold material is placed on the turntable. Cross-sectional view taken along line XX in FIG. 4. FIG. FIG. 4 is a cross-sectional view showing a second heating step and a first cooling step. FIG. FIG. 11 is a cross-sectional view showing a second heating step and a first cooling step in an ingot casting apparatus according to a first modified example. FIG. 11 is a cross-sectional view showing a second heating step and a first cooling step in an ingot casting apparatus according to a second modified example.

The following describes an ingot casting device (hereinafter, simply referred to as "casting device") 1 according to one embodiment of the present invention, using Figures 1 to 5. The casting device 1 is used for the purpose of producing metal ingots by melting granular material of precious metal (e.g., gold, silver, etc.) called "shot," then cooling and solidifying it.

When the casting device 1 is used, multiple mold materials M (up to six in this embodiment) are placed inside the chamber 3 with granular material contained in recesses Mr formed in each mold material M. The mold materials M are then heated to melt the granular material, and the mold materials M are then cooled to produce a metal ingot.

As shown in Figures 1 to 5, the casting device 1 includes as its components a housing 2, a chamber 3, a turntable 4, a rotation mechanism 42, a heating mechanism 5, a heating lifting mechanism 52, and a cooling lifting mechanism 6. The casting device 1 is also connected to a vacuum pump and an inert gas injection cylinder (not shown). Each component will be described below in order. In this embodiment, the lower right side in Figure 1 will be described as the front of the casting device 1, and the upper right side in Figure 1 will be described as the right side of the casting device 1.

The housing 2 constitutes the outer shape of the casting device 1 and houses each of the components of the casting device 1. On the right side of the top surface of the housing 2, an operation unit 2a is provided for a user to control various operations of the casting device 1 (reducing pressure in the chamber 3 and injecting inert gas, rotating the turntable 4 by the rotation mechanism 42, heating the mold material M by the heating mechanism 5, driving the heating and lifting mechanism 52, cooling the mold material M by the cooling and lifting mechanism 6, etc.). When the user operates the operation unit 2a, various operations of the casting device 1 are controlled via a control device not shown.

A chamber 3 is provided on the top surface of the housing 2. The chamber 3 comprises a hollow main body 31 and a lid 32 that can close the main body 31. The lid 32 is attached to the housing 2 via a hinge 33 so that it can rotate up and down. The lid 32 is provided with a window 32a made of a transparent plate so that the inside of the chamber 3 can be seen when the main body 31 is closed.

A disk-shaped turntable 4 with a vertical rotation axis is provided at the bottom of the chamber 3. The turntable 4 is made of a heat-resistant material, for example, a laminate of glass fiber sheets bound with a binder. A rotation mechanism 42 that rotates the turntable 4 is housed below the main body 31 inside the housing 2. As shown in FIG. 5, the rotation mechanism 42 is fixed to the underside of the bottom of the main body 31.

As shown in Figures 2 and 3, the turntable 4 has six openings 4a that penetrate the turntable 4 at angles of 60 degrees each. The inner edge of each opening 4a is provided with a placement section 41 in which the mold material M can be placed. The placement section 41 is made of heat-resistant ceramic. Note that the number of openings 4a (placement sections 41) formed in the turntable 4 is not limited to six, and can be any other number.

The rotation mechanism 42 is composed of a motor support part 43, a motor 44, and a shaft member 45. The motor support part 43 is fixed to the underside of the center part of the main body part 31 and supports the motor 44. The motor 44 rotates the shaft member 45 under the control of the control device. The turntable 4 is fixed to the shaft member 45, and the rotation of the shaft member 45 rotates the turntable 4 clockwise in a plan view (see the arrow in Figure 2). In this way, the rotation mechanism 42 rotates the turntable 4, thereby changing the positions of the six arrangement parts 41.

A heating coil 51 is provided as the heating mechanism 5 on the right side of the inner surface of the chamber 3. The heating coil 51 is provided above the turntable 4 and is arranged so that the winding direction is approximately horizontal. A voltage is applied to the heating coil 51 under the control of a control device. The heating coil 51 is a tubular member made of copper with a hollow interior, and it is possible to circulate cooling water inside.

As shown in Figures 3 and 5, a heating lifting mechanism 52 is provided below the turntable 4 in the same location as the heating coil 51 in a plan view. The heating lifting mechanism 52 is composed of a cylinder support part 53, a heating lifting cylinder 54, a heating rod 55, a block support member 56, and a lifting block 57.

The cylinder support 53 is fixed to the underside of the main body 31 below the heating coil 51, and supports the heating lift cylinder 54, which is an air cylinder. The heating lift cylinder 54 moves the heating rod 55 up and down under the control of the control device. A heat-resistant ceramic lift block 57 is fixed to the upper end of the heating rod 55 via a block support member 56. When the heating lift cylinder 54 is driven, the lift block 57 rises as shown in FIG. 6. At this time, the upper surface of the lift block 57 passes through the opening 4a of the turntable 4 and is displaced above the turntable 4.

In the casting device 1 according to this embodiment, the mold material M is made of a conductive carbon material. As shown in Figs. 6 and 7, the heating and lifting mechanism 52 raises the mold material M inside the heating coil 51, and then applies a voltage to the heating coil 51 as shown by the arrow C in Figs. 6 and 7. In this way, in the casting device 1, the mold material M is induction-heated by the heating coil 51, thereby performing a heat treatment.

As described above, in the casting device 1 according to this embodiment, the mold material M is heated by induction heating using the heating coil 51. This makes it possible to suppress the temperature rise of the heating mechanism 5, thereby suppressing the effects of heat from the heating mechanism 5. Note that the casting device 1 can also be configured to heat the mold material M using other methods, such as heating with an electric heater.

As described above, in the casting device 1 according to this embodiment, the heat treatment is performed while the mold material M is elevated by the heating and lifting mechanism 52. This allows the mold material M to be heated at a location away from the turntable 4, thereby suppressing the thermal effect of the mold material M heated by the heating mechanism 5 on the turntable 4.

A cooling lifting mechanism 6 (first cooling lifting mechanism 6A) is provided on the underside of the chamber 3 at a position displaced 60 degrees clockwise from the heating lifting mechanism 52. In addition, a cooling lifting mechanism 6 (second cooling lifting mechanism 6B) is provided on the underside of the chamber 3 at a position displaced 60 degrees clockwise from the first cooling lifting mechanism 6A. In this embodiment, the first cooling lifting mechanism 6A and the second cooling lifting mechanism 6B have the same configuration, so the first cooling lifting mechanism 6A will be described below.

The cooling lifting mechanism 6 is composed of a cylinder support part 61, a cooling lifting cylinder 62, a cooling rod 63, a cooling block 64, and a cooling plate 65. The cylinder support part 61 is fixed to the underside of the main body part 31, and supports the cooling lifting cylinder 62, which is an air cylinder. The cooling lifting cylinder 62 moves the cooling rod 63 up and down under the control of a control device. The cooling plate 65, which is a copper plate, is fixed to the upper end of the cooling rod 63 via the cooling block 64.

A cooling path 64a is formed inside the cooling block 64. A cooling path 65a is formed inside the cooling plate 65. The cooling paths 64a and 65a are connected to each other and to a pipe P. As shown in Figures 7 and 8, cooling water W is supplied from the pipe P, and the cooling water W flows inside the cooling block 64 and the cooling plate 65.

When the cooling lift cylinder 62 is driven, the cooling plate 65 is raised as shown in Figures 7 and 8. At this time, the upper surface of the cooling plate 65 passes through the opening 4a of the turntable 4 and is displaced slightly above the turntable 4. In this embodiment, the cooling lift mechanism 6 circulates cooling water W inside the cooling plate 65, and then raises the cooling plate 65 in contact with the mold material M as shown in Figures 7 and 8. In this way, in the casting device 1, the cooling process is performed by circulating cooling water W through the cooling plate 65.

As described above, in the casting device 1 according to this embodiment, the cooling water W is circulated through the cooling plate 65 to cool the mold material M, thereby improving the cooling efficiency of the cooling lift mechanism 6 for the mold material M. Note that the casting device 1 can also be configured to cool the mold material M using other methods, such as cooling with cooling air.

As described above, in the casting device 1 according to this embodiment, the cooling process is performed with the mold material M elevated by the cooling lifting mechanism 6. This allows the cooling plate 65 to be in close contact with the mold material M, improving the efficiency of cooling the mold material M by the cooling lifting mechanism 6.

In this embodiment, two cooling lifting mechanisms 6 are provided so that one mold material M is subjected to the cooling process twice, but the casting device 1 only needs to be equipped with at least one cooling mechanism, and the number is not limited. In other words, the casting device 1 can be equipped with one or three or more cooling mechanisms (up to five in this embodiment).

Next, the procedure for using the casting device 1 according to this embodiment will be described with reference to Figures 1 to 8. Below, we will explain the case of producing a metal ingot using six mold materials M, which is the maximum number that can be used with the casting device 1.

First, metal particles are placed in the recesses Mr formed in each mold material M and then the recesses Mr are covered, and each mold material M is placed in the six placement sections 41 as shown in FIG. 4. After that, the lid 32 of the chamber 3 is closed to seal the main body 31, and the chamber 3 is evacuated and an inert gas is injected.

The mold material M described in this embodiment has six recesses Mr formed in each piece, as shown in FIG. 4. Therefore, as shown in FIG. 4, the casting device 1 can produce up to 36 metal ingots in one casting process.

In the casting device 1 according to this embodiment, it is also possible to change the size and number of recesses Mr formed in the mold material M depending on the size (weight) of the metal ingot to be produced. For example, if two recesses Mr are formed in one mold material M, the casting device 1 can produce up to 12 metal ingots in one casting process.

In the casting device 1 according to this embodiment, the turntable 4 rotates clockwise in a plan view, so the mold material M is heat-treated counterclockwise. In FIG. 4, the mold material M that is first heat-treated is the first mold material M1, and the mold materials M2 to M6 are heat-treated in the counterclockwise direction.

Next, as shown in FIG. 6, the heating lift cylinder 54 is driven to raise the first mold material M1 to the inside of the heating coil 51 on the upper surface of the lift block 57, and a voltage is applied to the heating coil 51. This causes the first mold material M1 to be induction heated by the heating coil 51, thereby performing a heating process and melting the granular material in the first mold material M1 (first heating step).

Then, the heating lifting cylinder 54 is driven to lower the first mold material M1 onto the top surface of the turntable 4. Furthermore, the rotation mechanism 42 is driven to rotate the turntable 4 by 60 degrees clockwise in a plan view. As a result, the first mold material M1 is positioned in the same position as the first cooling lifting mechanism 6A, and the second mold material M2 is positioned in the same position as the heating coil 51 and heating lifting mechanism 52.

Next, as shown in FIG. 7, the heating lift cylinder 54 is driven to raise the second mold material M2 to the inside of the heating coil 51 on the upper surface of the lift block 57, and a voltage is applied to the heating coil 51. This causes the second mold material M2 to be induction heated by the heating coil 51, thereby performing a heating process, and melts the granular material in the second mold material M2 (second heating process).

At the same time as the second heating step, as shown in FIG. 7, in the first cooling lifting mechanism 6A, the cooling plate 65 is raised against the first mold material M1 while cooling water W is circulating inside the cooling plate 65. This causes the first cooling process to be performed by circulating the cooling water W through the cooling plate 65, and the molten metal in the first mold material M1 is solidified (first cooling step).

In this way, in the casting device 1, the heating process in the heating mechanism 5 and the cooling process in the cooling lifting mechanism 6 (first cooling lifting mechanism 6A and second cooling lifting mechanism 6B) can be performed simultaneously. Furthermore, the turntable 4 is rotated 60 degrees to simultaneously heat the third mold material M3 in the heating mechanism 5, cool the second mold material M2 a first time in the first cooling lifting mechanism 6A, and cool the first mold material M1 a second time in the second cooling lifting mechanism 6B (third heating process and second cooling process).

Similarly, the turntable 4 is rotated 60 degrees at a time to perform the fourth heating step and the third cooling step, the fifth heating step and the fourth cooling step, and the sixth heating step and the fifth cooling step. Thereafter, as shown in FIG. 8, when the sixth mold material M6 is positioned in the same position as the first cooling and lifting mechanism 6A, the first mold material M1 is positioned in the same position as the heating coil 51 and the heating and lifting mechanism 52, so that during the sixth cooling step, only the sixth mold material M6 is cooled in the first cooling and lifting mechanism 6A. After the sixth mold material M6 has been sufficiently cooled in the first cooling and lifting mechanism 6A, the lid 32 of the chamber 3 is opened, and the mold material M and the 36 metal ingots are removed.

As described above, in the casting device 1 according to this embodiment, the heating mechanism 5 heats one mold material M, thereby enabling a heating process in which the granular material contained in the one mold material M is melted into molten metal, and the cooling and lifting mechanism 6 cools the other mold material M, thereby enabling a cooling process in which the molten metal contained in the other mold material M is solidified into a metal ingot, all at the same time.

This allows a large number of metal ingots to be cast with a single vacuum and injecting of inert gas into the chamber 3. In other words, the number of times that the chamber 3 needs to be vacuumed and the inert gas needs to be injected relative to the number of metal ingots to be produced can be reduced, improving the efficiency of casting metal ingots.

In addition, in the casting device 1, the heating process for one mold material M and the cooling process for another mold material M are performed simultaneously, so that the processes required for casting metal ingots can be carried out in parallel, improving the efficiency of casting metal ingots. In other words, it is possible to shorten the time required to cast a large number of metal ingots.

Next, a casting device according to a first modified example of the present invention will be described with reference to FIG. 9. The casting device described after this modified example has a configuration in which an upper cooling section 70 has been added to the configuration of the casting device 1 according to the above embodiment. That is, the configuration of the subsequent casting devices is the same as that of the casting device 1 except for the upper cooling section 70, so the same components as those of the casting device 1 are given the same reference numerals and detailed descriptions are omitted, and the configuration of the upper cooling section 70 will be mainly described.

Figure 9 is a cross-sectional view showing the second heating step and the first cooling step (corresponding to Figure 7 in the above embodiment) in the ingot casting device according to this modified example. As shown in Figure 9, the upper cooling section 70 is configured to include a fixing member 71, a support member 72, and an upper cooling plate 73.

The fixing member 71 is a rod-shaped member fixed to the inner wall of the main body 31 of the chamber 3. A support member 72 extending toward the center of the main body 31 is fixed to the upper part of the fixing member 71. An upper cooling plate 73, which is a copper plate with a ceramic heat insulating plate on the underside, is connected to the lower part of the support member 72 via a swivel bolt.

As shown in FIG. 9, the upper cooling plate 73 is disposed above the first cooling lifting mechanism 6A. As a result, when the first cooling lifting mechanism 6A lifts the first mold material M1 via the cooling plate 65, the first mold material M1 is sandwiched between the cooling plate 65 and the upper cooling plate 73 of the upper cooling section 70.

In this modified example, by configuring as described above, the cooling process is performed with the upper cooling plate 73 in contact with the upper surface of the mold material M. This promotes cooling by heat conduction from the upper surface of the mold material M to the upper cooling plate 73. In other words, with the casting device of this modified example, by sandwiching the mold material M between the cooling plate 65 and the upper cooling section 70, the cooling efficiency of the mold material M by the first cooling lifting mechanism 6A can be improved.

Next, a casting device according to a second modified example of the present invention will be described with reference to Figure 10. The configuration of the casting device described after this modified example is the same as that of the casting device 1, except for the upper cooling section 170. Therefore, the same components as those of the casting device 1 are given the same reference numerals and detailed descriptions are omitted, and the configuration of the upper cooling section 170 will be mainly described.

Figure 10 is a cross-sectional view showing the second heating step and the first cooling step in the ingot casting device according to this modified example. As shown in Figure 10, the upper cooling section 170 is configured to include a fixing member 171, a support member 172, an upper cooling plate 173, and a pipe 174.

The fixing member 171 is a rod-shaped member fixed to the inner wall of the main body 31 of the chamber 3. A support member 172 extending toward the center of the main body 31 is fixed to the upper part of the fixing member 171. An upper cooling plate 173, which is a copper plate member, is connected to the lower part of the support member 172 via a swivel bolt. A cooling passage 173a is formed inside the upper cooling plate 173, which is connected to an external cooling pump by piping 174.

As shown in FIG. 10, the upper cooling plate 173 is disposed above the first cooling lifting mechanism 6A. As a result, when the first cooling lifting mechanism 6A lifts the first mold material M1 via the cooling plate 65, the first mold material M1 is sandwiched between the cooling plate 65 and the upper cooling plate 173 of the upper cooling section 170.

In this modified example, by configuring as described above, the upper cooling plate 173 is abutted against the upper surface of the mold material M during the cooling process, and cooling water is circulated through the cooling passage 173a while the cooling process is being carried out. This further promotes cooling by heat conduction from the upper surface of the mold material M to the upper cooling plate 173. In other words, according to the casting device of this modified example, by circulating cooling water through the upper cooling plate 173 while the mold material M is sandwiched between the cooling plate 65 and the upper cooling section 170, the cooling efficiency of the mold material M by the first cooling lifting mechanism 6A can be further improved.

1 Casting equipment (ingot casting equipment)
2 Housing 2a Operation unit
3 Chamber 4 Turntable
4a Opening 5 Heating mechanism
6 Cooling lifting mechanism (cooling mechanism)
6A First cooling and lifting mechanism 6B Second cooling and lifting mechanism
31 Main body 32 Lid
32a Window portion 33 Hinge
41 Placement unit 42 Rotation mechanism
43 Motor support portion 44 Motor
45 Shaft member
51 heating coil 52 heating lifting mechanism
53 Cylinder support portion 54 Heating lift cylinder
55 Heating rod 56 Block support member
57 Lifting block
61 Cylinder support portion 62 Cooling lift cylinder
63 Cooling rod 64 Cooling block
64a Cooling path 65 Cooling plate
65a Cooling path
70 Upper cooling portion 71 Fixing member
72 Support member 73 Upper cooling plate
170 Upper cooling portion 171 Fixing member
172 Support member 173 Upper cooling plate
173a Cooling passage 174 Piping
M shape material M1 to M6 1st shape material to 6th shape material
Mr Concave W Cooling water
P Piping

Claims (7)

A chamber including a hollow main body and a lid capable of closing the main body;
A turntable provided at a lower portion within the chamber;
A rotation mechanism that rotates the turntable;
A heating mechanism provided in the chamber;
At least one cooling mechanism provided at a location different from the heating mechanism in a plan view,
The turntable is formed with a plurality of placement sections in which a mold material containing metal particles can be placed,
the rotation mechanism rotates the turntable to vary the positions of the plurality of arrangement units;
This ingot casting device enables simultaneous performance of a heating process in which the granular material contained in one of the mold materials is melted into molten metal by the heating mechanism heating one of the mold materials, and a cooling process in which the molten metal contained in the other mold material is solidified into a metal ingot by the cooling mechanism cooling the other mold material. the heating mechanism is provided above the turntable within the chamber,
A heating and lifting mechanism is provided below the turntable at the same location as the heating mechanism in a plan view;
2. The ingot casting device according to claim 1, wherein the heating mechanism performs the heat treatment while the heating and elevating mechanism elevates one of the mold members. the heating mechanism includes a heating coil;
The mold material is made of a conductive material,
3. The ingot casting apparatus according to claim 2, wherein the heating and lifting mechanism raises the one mold material inside the heating coil and applies a voltage to the heating coil to inductively heat the one mold material, thereby performing a heat treatment. The cooling mechanism is a cooling lifting mechanism provided under the turntable,
The ingot casting device according to claim 1 , wherein the cooling and lifting mechanism performs the cooling process in a state in which the other mold material is elevated. The ingot casting device according to claim 4, wherein the cooling lifting mechanism includes a metal cooling plate and a cooling path formed inside the cooling plate, and performs a cooling process by circulating cooling water through the cooling path while the cooling lifting mechanism lifts the other mold material via the cooling plate. the cooling lifting mechanism includes an upper cooling part fixed above the cooling plate,
6. The ingot casting device according to claim 5, wherein when the cooling lifting mechanism lifts the other mold material via the cooling plate, the other mold material is sandwiched between the cooling plate and the upper cooling section. 7. An ingot casting apparatus as described in claim 6, wherein a cooling passage is formed inside the upper cooling section, and cooling treatment is performed by circulating cooling water through the cooling passage while the other mold material is sandwiched between the cooling plate and the upper cooling section.

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