Take pot heating device

Abstract

The present invention provides a ladle heating device that further shortens the ladle heating time and enables more uniform heating of the ladle. [Solution] The ladle heating device 1 includes a heater section 4 having a vertical heater 10. The vertical heater 10 includes a first winding section 31 and a second winding section 32. The first winding section 31 and the second winding section 32 generate heat electrically and can be arranged in a state that extends vertically within the hot water storage space F of the ladle P. The first winding section 31 is located below the first winding section 31 and has a greater heat generation per unit length than the first winding section 31.

Description

Technical Field

[0001] The present invention relates to a ladle heating device for heating a ladle.

Background Art

[0002] As a ladle heating device, the one described in Japanese Patent Application Laid-Open No. 2015-213921 (Patent Document 1) is known. This ladle heating device heats a ladle. The ladle has a bottomed and upwardly open container-shaped ladle body and a hot water outlet connected to the ladle body. The ladle receives and stores molten metal, which is a liquid metal, in the ladle body, and transfers the molten metal from the hot water outlet to the pouring target. In a casting factory, the ladle receives, that is, receives hot molten metal from a melting furnace or a forehearth, transports the molten metal to the casting site, injects, that is, pours the molten metal into a mold or the like, or transfers the molten metal into another ladle for pouring or a molten metal holding furnace. When the temperature of the ladle is low, the heat of the received molten metal is taken away by the ladle, and the temperature of the molten metal decreases, leading to a deterioration in the quality of the molten metal. Therefore, the ladle heating device heats the ladle before receiving hot molten metal to preheat and keep warm the ladle. This ladle heating device includes a lid portion that closes the opening of the ladle and an electric resistance heating heater that is attached to the lid portion and heats the inside of the ladle. The electric resistance heating heaters are provided in three, equally spaced in the circumferential direction, and each extending downward.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the ladle heating device described above, three electric resistance heaters extending downward from the lid are arranged at equal intervals in the circumferential direction, so there is room for improvement in shortening the heating time, and in particular the bottom of the ladle body and the spout are more difficult to heat than other parts.

[0005] The main objective of the present invention is to provide a ladle heating device that further shortens the ladle heating time. Another main objective of the present invention is to provide a ladle heating device that enables more uniform heating of the ladle. [Means for solving the problem]

[0006] This specification discloses a ladle heating device. This ladle heating device may include a heater section having a vertical heater. The vertical heater may include a vertical heating element. The vertical heating element is electrically heated and may be positioned to extend vertically within the hot water storage space of the ladle. The amount of heat generated per unit length in the vertical heating element may increase stepwise or continuously as it goes downwards. Furthermore, the ladle heating device may include a heater section having a vertical heater. The vertical heater may include a vertical heating element. The vertical heating element generates heat electrically and can be arranged in a manner that extends vertically within the hot water storage space of the ladle. It may include a first vertical heating element and a second vertical heating element located below the first vertical heating element, which has a greater heat output per unit length than the first vertical heating element. Furthermore, the ladle heating device may include a heater section comprising a vertical heater having a vertical heating element and a lower heater having a lower heating element. The vertical heating element is electrically heated and may be positioned to extend vertically within the hot water storage space of the ladle. The lower heating element is electrically heated and may be positioned within the hot water storage space. The lower heater may be held below the vertical heater. Furthermore, the ladle heating device may also include a heater section having a vertical heater and a fan section having a fan. The vertical heater may have a vertical heating element. The vertical heating element is electrically heated and may be positioned to extend vertically within the hot water storage space of the ladle. The fan may generate airflow within the hot water storage space by rotating. [Effects of the Invention]

[0007] The main effect of the present invention is to provide a ladle heating device that further shortens the ladle heating time. Another main effect of the present invention is to provide a ladle heating device that enables more uniform heating of the ladle. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic cross-sectional view of the ladle heating device and ladle according to the present invention. [Figure 2] This is a top view of Figure 1. [Figure 3] Figure 1 is a schematic cross-sectional view of the fan section in the ladle heating device. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the present invention and modifications thereof will be described with reference to the drawings as appropriate. Furthermore, the present invention is not limited to the following embodiments and modifications.

[0010] Figure 1 is a schematic cross-sectional view of the ladle heating device 1 and ladle P according to the said configuration. Figure 2 is a top view of Figure 1. The ladle P has a ladle body M and a spout E. The ladle body M has a molten metal storage space F and a bottom B. The molten metal storage space F is open upwards and can store molten metal, i.e., it can store molten metal. The bottom B is the lower wall of the ladle body M and is located below the molten metal storage space F. The outlet E protrudes outward from the ladle body M. The outlet E is cylindrical. The internal space of the outlet E is connected to the molten metal storage space F. For the sake of explanation, the direction in which the outlet E protrudes is assumed to be to the right. Also, the direction of the bottom B when viewed from the molten metal storage space F is assumed to be downward. Furthermore, the direction perpendicular to the plane of Figure 1 towards the viewer is assumed to be the forward direction, and the direction perpendicular to the plane of Figure 1 towards the viewer is assumed to be the backward direction. Various directions may be appropriately changed depending on at least one of the installation and operation conditions of the components or parts. The molten metal may be molten aluminum, molten zinc or other non-ferrous metals, or molten iron or other metals.

[0011] The ladle heating device 1 comprises a lid 2, a heater 4, a terminal cover 5, and a fan 6.

[0012] The lid portion 2 is a disc-shaped component made of insulating material. The lid portion 2 is positioned on the upper side of the ladle body M and covers the upper side of the hot water storage space F. Furthermore, the material of lid 2 is not limited to thermal insulation. Also, the shape of lid 2 is not limited to a disc shape. The materials and shapes of other components and parts can also be changed in various ways.

[0013] The heater unit 4 has a plurality (3) of vertical heaters 10 and a plurality (3) of lower heaters 12.

[0014] Since each vertical heater 10 is similar to the others except for its arrangement, unless otherwise specified, only one vertical heater 10 is described. The vertical heater 10 is a radiant heater and includes a coil section 20, a wiring section 22, and an overheating thermocouple 24. However, the vertical heater 10 is not limited to a radiant heater. The coil part 20 has a core part 30, a first winding part 31 as a first longitudinal heating part, and a second winding part 32 as a second longitudinal heating part. The first winding part 31 and the second winding part 32 constitute the longitudinal heating part. The core part 30 is a rod-shaped member made of a heat insulating material and extends vertically. The first winding part 31 is a conducting wire wound around approximately two-thirds of the upper part of the core part 30. The second winding part 32 is a conducting wire wound around approximately one-third of the lower part of the core part 30. The number of turns per unit length of the conducting wire, that is, the turn density, in the second winding part 32 is larger than the turn density in the first winding part 31. The turn density in the coil part 20 is in two steps where it becomes larger in the lower stage. The first winding part 31 and the second winding part 32 are a series of conducting wires. The first winding part 31 and the second winding part 32 generate heat when energized. The amount of heat generated per unit length, that is, the heat generation density, in the second winding part 32 is larger than the heat generation density of the first winding part 31. The amount of heat generated per unit length in the second winding part 32 as the second longitudinal heating part is larger than the amount of heat generated per unit length in the first winding part 31 as the first longitudinal heating part. If at least one of the first winding part 31 and the second winding part 32 is made of, for example, a chromel-based alloy, it can generate heat up to 1100°C. Thereby, in addition to heat transfer by air, radiation heating by infrared rays becomes possible, and mainly the inner surface of the cooking pot P can be heated. This also holds true for other heating parts. Incidentally, the vertical lengths of the first winding part 31 and the second winding part 32 can be changed in various ways. Also, the turn density in the coil part 20 may be in one step, that is, constant as a whole, or may be in three steps or more, or may be a continuous step where it gradually becomes larger as going downward. The change in the heat generation density may be implemented by other means than the change in the turn density, such as the change in the resistance value based on the change in the width of the plate-shaped heating element.

[0015] The wiring part 22 has a cylindrical part 34 and a wire part 35. The cylindrical part 34 is a cylindrical member made of a heat insulating material and extends vertically. The cylindrical part 34 is held by the lid part 2 and penetrates the lid part 2. A core part 30 is arranged below the cylindrical part 34. The cylindrical part 34 holds the core part 30. The wire part 35 includes a plurality (three) of wires. The wire part 35 is connected to the first winding part 31. The wire part 35 supplies power to the first winding part 31 and the second winding part 32. The wire part 35 passes through the cylindrical part 34 and is connected to a power supply part (not shown). The over-temperature thermocouple 24 can detect the temperature of the coil part 20 and is connected to a control part (not shown) in order to suppress a situation where the heat generation of the coil part 20 becomes excessive, resulting in over-temperature, and adverse effects such as disconnection or deformation occur in the vertical heater 10. When the temperature of the coil part 20 reaches a predetermined threshold value or higher, the control part stops the power supply to the coil part 20.

[0016] Each vertical heater 10 is arranged at equal intervals in the circumferential direction around a virtual central axis extending vertically in the lid part 2. Each vertical heater 10 heats the inner surface of the cooking pot P and heats the hot water storage space F by the heat generation in the first winding part 31 and the second winding part 32. A part of each vertical heater 10 (here, the rightmost vertical heater 10 in FIG. 2) is arranged adjacent to the hot water outlet E. With such an arrangement, the hot water outlet E is sufficiently heated. In addition, the arrangement of each vertical heater 10 may be variously changed, such as being at unequal intervals in the circumferential direction. The arrangements of other members and parts can also be variously changed in the same way. Also, in order to heat the hot water outlet E more sufficiently, the vertical heater 10 adjacent to the hot water outlet E may have a winding part with a large winding number density at the upper part close to the hot water outlet E and a winding part with a small winding number density at the lower part, or may have a winding part with a multi-step or steplessly increasing winding number density from the lower part to the upper part, or may have a winding part with an increasing winding number density as the distance from the hot water outlet E is closer.

[0017] In addition, since each lower heater 12 is the same as each other except for the arrangement, one lower heater 12 will be described unless otherwise specified. The lower heater 12 is the same as the coil section 20 of the vertical heater 10, except for its arrangement and winding density. The first end of the lower heater 12 is connected to the lower end of the vertical heater 10, and the second end of the lower heater 12 is connected to the lower end of the vertical heater 10 that is circumferentially adjacent to the vertical heater 10 to which the first end of the lower heater 12 is connected. The lower heater 12 is held at the bottom of each of the pair of vertical heaters 10. The lower heater 12 is horizontal. The three lower heaters 12 are arranged in a triangular shape when viewed from above to below. The winding density of the winding portion of the lower heater 12 is constant overall. The winding portion of the lower heater 12 is a type of heating element of the lower heater 12, and is a type of lower heating element. Electrically, the winding section of one lower heater 12 is connected to the first winding section 31 and the second winding section 32 of one vertical heater 10. In other words, three sets of "L"-shaped vertical heaters 10 and lower heaters 12 are arranged. Each lower heater 10 heats the bottom B of the ladle P and the hot water storage space F by generating heat in its winding section. Furthermore, the winding density of the lower heater 12 may be varied in stages. At least one of the mechanical and electrical arrangements of the lower heater 12 relative to the vertical heater 10 may be different from those described above. Some or all of the lower heater 12 does not have to be horizontal. The lower heating element may be something other than a winding.

[0018] The terminal cover 5 is shown by a dashed line in Figures 1 and 2 and covers the top and radially outward of the cylindrical portion 34 of the vertical heater 10. The terminal cover 5 is split in half and is attached to the lid portion 2. Furthermore, the terminal cover 5 does not have to be split in half, and it can be attached to parts other than the lid 2.

[0019] Figure 3 is a schematic cross-sectional view of the fan section 6. The fan unit 6 comprises a motor 40, a shaft 42, a bearing unit 44, a plurality (two) of fans 46, and a fan cover 48. The fan unit 6 is positioned radially inward of each vertical heater 10 when viewed from above to below. The motor 40 comprises a motor body 50 and a motor shaft 52, and rotates the motor shaft 52 around its virtual central axis. The motor shaft 52 extends vertically. The motor 40 is connected to a power supply (not shown). The power supply for the motor 40 may be separate from or shared with the power supply for the heater unit 4. The shaft 42 is a rod-shaped member that extends vertically. The shaft 42 is integrally connected to the motor shaft 52 and rotates together with the motor shaft 52 around its own virtual central axis. The bearing section 44 has a cylindrical section 54 and a plurality (two) of bearings 56. The cylindrical section 54 extends vertically and passes through the center of the lid section 2 vertically. The motor shaft 52 and shaft body 42 are arranged radially inward of the cylindrical section 54. Each bearing 56 rotatably holds the shaft body 42 and is arranged vertically. The bearing section 44 is held by the lid section 2.

[0020] Each fan 46 is made of ceramic and generates airflow, or wind, through rotation. Each fan 46 is positioned vertically at the lower part of the shaft 42. Each fan 46 is integrally mounted with the shaft 42. Furthermore, the number of fans 46 may be one or three or more. If multiple fans 46 are provided, they may be of different types, such that some types differ from others.

[0021] The fan cover 48 is a cylindrical member made of metal and extends vertically. A lower opening 57 is provided at the lower end of the fan cover 48, which opens downwards. The lower opening 57 is located at the bottom of the hot water storage space F. The shaft 42 and the fan 46 are positioned radially inward of the fan cover 48. The fan cover 48 surrounds the shaft 42 and the fan 46. The fan cover 48 is held in place by the lid portion 2 via the bearing portion 44. The fan cover 48 has multiple (three) upper openings 58 at the top adjacent to the lid portion 2. Each upper opening 58 extends vertically and circumferentially, and is arranged at equal intervals in the circumferential direction. Furthermore, the fan cover 48 may be directly held by the lid portion 2. The lower opening 57 may be located at the lower part of the fan cover 48 other than the lower end, or it may open in a direction other than downward, such as a radial opening, or there may be multiple openings. Also, the upper opening 58 may be omitted, or there may be one or two openings, or four or more openings. Moreover, the upper opening 58 may be located at the upper part of the fan cover 48 that is not adjacent to the lid portion 2, or it may be spaced unevenly in the circumferential direction. Furthermore, at least one of the shapes and sizes of some of the multiple upper openings 58 may differ from those of the other upper openings 58.

[0022] An example of the operation of such a ladle heating device 1 is described below. The user places the lid portion 2 of the ladle heating device 1 on top of the ladle P to preheat the ladle P. The lid portion 2 is positioned on the upper side of the ladle body M, and the protrusions of the heater portion 4 from the lid portion 2 and the protrusions of the fan portion 6 from the lid portion 2 are positioned inside the ladle body M, i.e., within the hot water storage space F. The second winding portion 32 of the heater portion 4, which has a denser winding density, and each lower heater 12 are adjacent to the bottom B of the ladle body M.

[0023] The user turns on the power to the heater unit 4, causing it to heat up, and also turns on the power to the motor 40, generating airflow through the rotation of the shafts 42 of each fan 46 within the hot water storage space F, thereby starting to heat the ladle P. Furthermore, the presence and degree of heat generation from the heater unit 4, and the presence and strength of airflow from each fan 46, depending on the elapsed time since the start of heating, may be controlled in various ways by the control unit. The control unit here may be the same as the control unit for the overheating thermocouple 24, or it may be a separate unit.

[0024] Due to the arrangement of the second winding section 32 and each lower heater 12, the heater section 4 generates more heat in the lower part of the hot water storage space F compared to the upper part. Therefore, compared to the case where the second winding section 32 and each lower heater 12 are absent, that is, when a high-temperature area is significantly generated at the top of the hot water storage space F due to convection, the large uneven distribution of heat to the top of the hot water storage space F is mitigated, and the bottom B of the ladle P is heated more sufficiently.

[0025] Furthermore, the uneven distribution of heat in the hot water storage space F is mitigated by the airflow from the fan unit 6, which moves the heat from the upper part of the storage space F to the lower part. That is, each fan 46 blows the relatively hot air that remains in the upper part of the hot water storage space F of the ladle P to the bottom B below. In addition, the fan unit 6 is equipped with a fan cover 48 that covers each fan 46, and the fan cover 48 has upper openings 58 that open in the upper part of the storage space F, and lower openings 57 that open in the lower part of the storage space F. Therefore, the airflow from each fan 46 descends radially inward from the upper openings 58, exits to the bottom of the storage space F from the lower openings 57, rises radially outward from the fan cover 48, and heads towards the upper openings 58. Thus, airflow in the storage space F that is more suitable for mitigating the uneven distribution of heat is generated. In particular, since the air is blown onto the bottom B, the bottom B is sufficiently heated, and sufficient temperature maintenance is achieved in the lower part of the storage space F.

[0026] The user completes the preheating of the ladle P by turning off the power to the heater unit 4 and the fan unit 6 once the ladle P has been heated to a predetermined level or higher. The heating to a predetermined level or higher may be determined by a temperature sensor (not shown) that indicates the temperature of the ladle P or an adjacent area has reached a predetermined temperature, or by the elapsed time since the start of heating, or by other methods. The user then pours molten metal into the ladle P, and with the molten metal in the storage space F, moves to the desired location or transfers the molten metal to the target from the outlet E. The ladle P is sufficiently preheated before receiving the molten metal. Therefore, the deterioration of the quality of the molten metal is suppressed. Furthermore, the preheating of the ladle P is performed by a heater unit 4 that generates heat electrically. Therefore, it is more energy-efficient and environmentally friendly compared to preheating with a gas burner.

[0027] The ladle heating device 1 described above provides the following effects. In other words, the ladle heating device 1 includes a heater section 4 having a vertical heater 10. The vertical heater 10 includes a first winding section 31 and a second winding section 32. The first winding section 31 and the second winding section 32 generate heat electrically and can be arranged to extend vertically within the hot water storage space F of the ladle P. The amount of heat generated per unit length in the first winding section 31 and the second winding section 32 increases in stages as you go downwards. Furthermore, the ladle heating device 1 includes a heater section 4 having a vertical heater 10. The vertical heater 10 includes a first winding section 31 and a second winding section 32. The first winding section 31 and the second winding section 32 generate heat electrically and can be arranged in a state that extends vertically within the hot water storage space F of the ladle P. The first winding section 31 is located below the first winding section 31 and has a greater heat generation per unit length than the first winding section 31. Therefore, the lower part of the hot water storage space F is heated more efficiently than the upper part, suppressing temperature unevenness within the storage space F. In addition, the entire ladle P, including the lower part, heats up more quickly, further shortening the heating time of the ladle P. Consequently, the ladle heating device 1 can quickly and efficiently heat the ladle P to suppress the deterioration of the molten metal quality.

[0028] Furthermore, the ladle heating device 1 includes a heater section 4 having a vertical heater 10 with a first winding section 31 and a second winding section 32, and a lower heater 12 with a lower winding section. The first winding section 31 and the second winding section 32 generate heat electrically and can be arranged in a state that extends vertically within the hot water storage space F of the ladle P. The lower winding section generates heat electrically and can be arranged within the hot water storage space F. The lower heater 12 is held below the vertical heater 10. Therefore, the lower heater 12 heats the lower part of the hot water storage space F more efficiently than the upper part, suppressing temperature unevenness within the hot water storage space F. In addition, the entire ladle P, including the lower part, heats up more quickly, further shortening the heating time of the ladle P. Consequently, the ladle heating device 1 can quickly and efficiently heat the ladle P to suppress deterioration of the molten metal quality.

[0029] Furthermore, if, in addition to providing the lower heater 12, the amount of heat generated per unit length in the first winding section 31 and the second winding section 32 is increased in stages as it goes downwards, the lower part of the hot water storage space F will be heated more sufficiently. Furthermore, if the lower heater 12 is provided, and the first winding section 31 and the second winding section 32 are configured to consist of the first winding section 31 and the second winding section 32 which is located below the first winding section 31 and has a greater heat output per unit length than the first winding section 31, then the lower part of the hot water storage space F will be heated more sufficiently.

[0030] Furthermore, the same number of lower heaters 12 are provided as the number of vertical heaters 10, with one lower heater 12 electrically connected to each vertical heater 10. Therefore, the electrical connection of the lower heater 12 is made simpler.

[0031] In addition, the ladle heating device 1 comprises a heater section 4 having a vertical heater 10 and a fan section 6 having a fan 46. The vertical heater 10 comprises a first winding section 31 and a second winding section 32. The first winding section 31 and the second winding section 32 generate heat electrically and can be arranged to extend vertically within the hot water storage space F of the ladle P. The fan 46 generates airflow within the hot water storage space F by rotating. Therefore, the airflow generated by the fan 46 suppresses temperature unevenness in the hot water storage space F. In addition, the airflow generated by the fan 46 allows the entire ladle P, including the lower part, to heat up more quickly, further shortening the heating time of the ladle P. Consequently, the ladle heating device 1 can quickly and efficiently heat the ladle P to suppress the deterioration of the molten metal quality.

[0032] Furthermore, the fan unit 6 has multiple fans 46. Therefore, even within the limited hot water storage space F, the airflow is increased, and the uneven distribution of temperature within the hot water storage space F is further suppressed. Furthermore, the fan unit 6 has a fan cover 48 surrounding the fan 46. The fan cover 48 can be positioned to extend vertically within the hot water storage space F, and has a lower opening 57 at its lower end. In addition, the fan cover 48 has upper openings 58 at its upper end. Therefore, the airflow in the hot water storage space F is such that hotter air from the upper part of the hot water storage space F1 enters the fan cover 48 through the upper openings 58, and hotter air is blown downwards through the lower openings 57, making it more suitable for suppressing temperature unevenness. In addition, multiple vertical heaters 10 are provided. The fan unit 6 is positioned between each vertical heater 10. Therefore, each vertical heater 10 and the fan unit 6 are more efficiently positioned to suppress the uneven distribution of air temperature within the hot water storage space F. [Explanation of symbols]

[0033] 1...Ladle heating device 4. Heater section 6. Fan Club 10. Vertical heater 12. Lower heater 31. First winding section 32. Second winding section 46 ··fan 48 ··Fan cover 57. Lower opening 58. Upper opening F... Hot water storage space P... Ladle.

Claims

1. It is equipped with a heater section that has a vertical heater, The aforementioned vertical heater is equipped with a vertical heating element, The aforementioned vertical heating element generates heat electrically and can be positioned to extend vertically within the hot water storage space of the ladle. The amount of heat generated per unit length in the aforementioned vertical heating section increases gradually or continuously as you move downwards. A ladle heating device characterized by the following features.

2. It is equipped with a heater section that has a vertical heater, The aforementioned vertical heater is equipped with a vertical heating element, The aforementioned vertical heating element is It generates heat through electricity, It can be positioned in a state that extends vertically within the hot water storage space of the ladle. It has a first vertical heating element and a second vertical heating element located below the first vertical heating element, which has a greater heat output per unit length than the first vertical heating element. A ladle heating device characterized by the following features.

3. It comprises a heater section having a vertical heater with a vertical heating element and a lower heater with a lower heating element. The aforementioned vertical heating element generates heat electrically and can be positioned to extend vertically within the hot water storage space of the ladle. The aforementioned lower heating element generates heat electrically and can be placed within the hot water storage space. The lower heater is held below the vertical heater. A ladle heating device characterized by the following features.

4. The amount of heat generated per unit length in the aforementioned vertical heating section increases gradually or continuously as you move downwards. The ladle heating device according to feature 3.

5. The vertical heating section comprises a first vertical heating section and a second vertical heating section located below the first vertical heating section, which has a greater heat output per unit length than the first vertical heating section. The ladle heating device according to feature 3.

6. The lower heaters are provided in the same number as the vertical heaters. One lower heater is electrically connected to one vertical heater. The ladle heating device according to feature 3.

7. It comprises a heater section having a vertical heater and a fan section having a fan. The aforementioned vertical heater is equipped with a vertical heating element, The aforementioned vertical heating element generates heat electrically and can be positioned to extend vertically within the hot water storage space of the ladle. The fan, through its rotation, creates airflow within the hot water storage space. A ladle heating device characterized by the following features.

8. The fan section has a plurality of fans. The ladle heating device according to feature 7.

9. The fan section has a fan cover that surrounds the fan. The aforementioned fan cover is It can be arranged in a state that extends vertically within the hot water storage space, The lower part has a lower opening. The ladle heating device according to feature 7.

10. The fan cover has an upper opening at its top. The ladle heating device according to feature 9.

11. Multiple vertical heaters are provided. The fan unit is positioned between each of the vertical heaters. The ladle heating device according to feature 7.

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