阅读说明：本技术 感应加热装置 (Induction heating device ) 是由 山本胜也 只野英显 松永和久 岩丸阳介 于 2020-03-02 设计创作，主要内容包括：本发明提供一种感应加热装置。该感应加热装置包括：按压部,其设置为以自上侧与感应加热线圈接触的方式自板构件沿着径向延伸；以及紧固构件,其配置于板构件的下部,利用紧固力经由按压部自上侧向下方按压感应加热线圈。(The invention provides an induction heating device. The induction heating apparatus includes: a pressing portion provided to extend from the plate member in a radial direction so as to contact the induction heating coil from an upper side; and a fastening member disposed below the plate member, and pressing the induction heating coil from the upper side to the lower side via the pressing portion by a fastening force.)

1. An induction heating apparatus, wherein,

the induction heating apparatus includes:

a furnace body into which a metal material is introduced;

an induction heating coil wound around an outer periphery of the furnace body;

a plurality of yokes arranged along the outer periphery of the induction heating coil;

a plate member that sandwiches the yoke from both sides in the circumferential direction;

a pressing portion provided on at least one of the plate members and extending from the plate member in a radial direction so as to contact the induction heating coil from an upper side; and

and a fastening member disposed at a lower portion of the plate member, and pressing the induction heating coil from an upper side to a lower side via the pressing portion by a fastening force.

2. The induction heating apparatus according to claim 1,

the induction heating apparatus further comprises a support member disposed at a lower side of the furnace body,

the plate member is fixed at a lower portion of the plate member with respect to the support member using the fastening member.

3. The induction heating apparatus according to claim 2,

the fastening member is configured to be disposed so as to straddle the lower portion of the plate member and the support member, and fasten and fix the lower portion of the plate member to the support member,

the pressing portion is configured to press the induction heating coil from an upper side to a lower side by a fastening force generated by the fastening member.

4. The induction heating apparatus according to claim 3,

the fastening means includes: a bolt part having a head connected to a lower portion of the plate member and a leg penetrating the support member; a nut portion that is screwed to the leg portion of the bolt portion that extends below the support member; and a spring member provided between a lower surface of the support member and the nut portion.

5. The induction heating apparatus according to any one of claims 2 to 4,

the fastening member is exposed below the supporting member.

6. The induction heating apparatus according to claim 1,

the pressing portion and the plate member are arranged in an inverted L shape such that the pressing portion extends in a radial direction from an upper end of the plate member extending in a vertical direction.

7. The induction heating apparatus according to claim 1,

the pressing portion is provided integrally with the plate member.

Technical Field

The present invention relates to an induction heating device, and more particularly to an induction heating device including a plurality of yokes arranged along an outer periphery of an induction heating coil wound around an outer periphery of a furnace body.

Background

Conventionally, there is known an induction heating device including a plurality of yokes arranged along an outer periphery of an induction heating coil wound around an outer periphery of a furnace body. Such an induction heating device is disclosed in, for example, japanese patent laid-open No. 8-189776.

Japanese patent application laid-open No. 8-189776 discloses an induction furnace (induction heating apparatus) including a crucible (furnace body) made of refractory, an induction heating coil wound around the outer periphery of the crucible, and a plurality of yokes arranged along the outer periphery of the induction heating coil. In the induction furnace described in japanese patent application laid-open No. 8-189776, the movement of the induction heating coil to the outer periphery is restricted by a yoke arranged along the outer periphery of the induction heating coil. In the induction furnace described in japanese patent application laid-open No. 8-189776, a gap is formed above the induction heating coil, and it is considered that the upward movement of the induction heating coil is not restricted.

Here, it is considered that, in a conventional induction heating apparatus as described in japanese patent application laid-open No. 8-189776, a movement restricting member for restricting upward movement of the induction heating coil is disposed above the induction heating coil. In this case, the movement restricting member itself needs to be fixed to the induction heating apparatus. Further, although not described in japanese patent application laid-open No. 8-189776, a relatively large-sized induction heating device is used in a conventional induction heating device such as that described in japanese patent application laid-open No. 8-189776 in order to increase the amount of metal melted by an induction heating coil (in order to improve productivity). For example, a relatively large induction heating apparatus having a height several times as large as the height of the worker is used.

Therefore, in the case where the movement restricting member is provided above the induction heating coil in the relatively large conventional induction heating device, an operator needs to perform work on the movement restricting member in order to perform work on the relatively large induction heating device, for example, during maintenance of the induction heating device. Therefore, there are the following problems: the position where the work is performed on the movement restricting member is a relatively high position where it is difficult for the worker to reach directly from the installation surface of the induction heating device, and therefore, the workability is lowered when performing the work on the member pressing the induction heating coil downward from the upper side.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an induction heating device capable of suppressing a reduction in workability when performing an operation of pressing a member of an induction heating coil downward from an upper side.

Means for solving the problems

In order to achieve the above object, an induction heating apparatus according to an aspect of the present invention includes: a furnace body into which a metal material is introduced; an induction heating coil wound around the outer periphery of the furnace body; a plurality of yokes arranged along the outer periphery of the induction heating coil; a plate member that sandwiches the yoke from both sides in the circumferential direction; a pressing portion provided on at least one of the plate members and extending from the plate member in a radial direction so as to contact the induction heating coil from an upper side; and a fastening member disposed below the plate member, and pressing the induction heating coil from the upper side to the lower side via the pressing portion by a fastening force.

In the induction heating apparatus according to an aspect of the present invention, as described above, the induction heating apparatus includes: a pressing portion provided to extend from the plate member in a radial direction so as to contact the induction heating coil from an upper side; and a fastening member disposed below the plate member, and pressing the induction heating coil from the upper side to the lower side via the pressing portion by a fastening force. Thus, since the fastening member that presses the induction heating coil from the upper side downward via the pressing portion by the fastening force is disposed at the lower portion of the plate member, the worker can perform the fastening operation of the fastening member at the lower portion of the induction heating device and perform the fixing operation of the member (pressing portion) that presses the induction heating coil from the upper side downward via the plate member with respect to the induction heating device. As a result, the position at which the work of pressing the member (pressing portion) of the induction heating coil downward from the upper side is performed is a relatively low position that is easily reached by the operator directly from the installation surface of the apparatus, and therefore, when the work of pressing the member of the induction heating coil downward from the upper side is performed, the reduction in workability can be suppressed.

In the induction heating apparatus according to the above aspect, it is preferable that the induction heating apparatus further includes a support member disposed on a lower side of the furnace body, and the plate member is fixed to the support member at a lower portion of the plate member using a fastening member. With this configuration, the plate member is fixed to the support member disposed below the furnace body using the fastening member at the lower portion of the plate member, and therefore, the fastening position of the fastening member can be reliably disposed at the lower portion of the induction heating apparatus. As a result, the worker can reliably perform the work on the fastening member at the lower portion of the induction heating device. Further, a pressing force for pressing the induction heating coil downward from above can be generated by a fastening force of the fastening member to the support member.

In this case, it is preferable that the fastening member is disposed so as to straddle the lower portion of the plate member and the support member, and fastens and fixes the lower portion of the plate member to the support member, and the pressing portion is configured to press the induction heating coil from the upper side to the lower side by a fastening force generated by the fastening member. With this configuration, since the fastening member is disposed so as to straddle the lower portion of the plate member and the support member, even when the lower portion of the plate member does not reach the support member, the lower portion of the plate member and the support member can be fastened and fixed by the fastening member.

In the above-described structure in which the pressing portion presses the induction heating coil from the upper side downward by a fastening force generated by the fastening member, the fastening member preferably includes: a bolt part, the head part of which is connected with the lower part of the plate member and the leg part of which penetrates through the supporting member; a nut portion that is screwed to a leg portion of the bolt portion that penetrates below the support member; and a spring member provided between the lower surface of the support member and the nut portion. Here, when the plurality of pressing portions, the plurality of plate members, the plurality of yokes, and the plurality of fastening members are provided along the circumferential direction of the induction heating coil, the height position of the induction heating coil pressed by the pressing portions, the height position of the yokes, the length of the plate members, and the like may not be uniform (there may be variations in accuracy). Therefore, with the above-described configuration, the above-described variations in accuracy can be absorbed by the expansion and contraction of the spring member provided between the lower surface of the support member and the nut portion. As a result, the pressing force generated by the fastening member can be prevented from becoming uneven in the circumferential direction of the induction heating coil due to the above-described variation in accuracy.

In the above-described structure in which the plate member is fixed to the support member using the fastening member at the lower portion of the plate member, the fastening member is preferably exposed below the support member. With this configuration, the worker can reach the fastening member below the support member where the fastening member is exposed. As a result, as compared with the case where the fastening member is not exposed below the support member, when the work of pressing the member of the induction heating coil downward from the upper side is performed, the reduction in workability can be further suppressed.

In the induction heating apparatus according to the above aspect, the pressing portion and the plate member are preferably arranged in a substantially inverted L shape such that the pressing portion extends in a radial direction from an upper end portion of the plate member extending in the vertical direction. Here, in the induction heating apparatus, a castable refractory (refractory concrete) is generally disposed above the induction heating coil and above a plurality of yokes disposed along the outer periphery of the induction heating coil. The castable refractory is replaced at predetermined intervals due to the aged deterioration accompanying the use of the apparatus. In contrast, when the portion where the castable refractory is disposed is relatively flat, a preformed castable refractory (molded castable refractory) is used, and when the portion where the castable refractory is disposed has undulations, a castable refractory (castable refractory) that requires the steps of removing, pouring, and drying each time the castable refractory is replaced is used. Therefore, with this configuration, the pressing portion and the plate member are arranged in a substantially inverted L shape, and therefore the pressing portion does not protrude upward from the plate member. That is, the upper sides of the plate member and the pressing portion are relatively flat. As a result, the molded castable refractory can be used on the upper side of the plate member with the yoke sandwiched from both sides in the circumferential direction, and therefore, the time required for replacing the castable refractory (that is, the time (downtime) for which the apparatus cannot be used) can be shortened as compared with the case where the castable refractory needs to be used in a step of disassembling, pouring, and drying each time the castable refractory needs to be replaced.

In the induction heating apparatus according to the above aspect, the pressing portion is preferably provided integrally with the plate member. With this configuration, the number of components can be reduced and the device structure can be simplified as compared with the case where the pressing portion is provided as a separate member from the plate member.

Drawings

Fig. 1 is a perspective cross-sectional view of an induction heating apparatus according to an embodiment of the present invention.

Fig. 2 is a plan view of an induction heating apparatus according to an embodiment of the present invention.

Fig. 3 is a side sectional view of an induction heating apparatus according to an embodiment of the present invention.

Fig. 4 is a perspective sectional view showing a detailed structure of a yoke support plate of an induction heating apparatus according to an embodiment of the present invention.

Detailed Description

Hereinafter, embodiments embodying the present invention will be described based on the drawings.

The structure of an induction heating apparatus 100 according to an embodiment of the present invention will be described with reference to fig. 1 to 4.

As shown in fig. 1, the induction heating apparatus 100 includes a furnace body 1, a heat insulating member 2, an induction heating coil 3, a yoke 4, a yoke support plate (japanese: iron equivalent て plate) 5, a cooling water circulation pipe 6, a hearth member 7, an upper refractory member 8, and an outer frame member 9. The induction heating apparatus 100 is an apparatus for heating the metal material 10 charged into the furnace body 1 by induction heating using the induction heating coil 3 to melt the metal material 10. The yoke support plate 5 is an example of a "plate member" in the claims. Further, the hearth member 7 is an example of the "support member" of the claims.

As shown in fig. 2, the furnace body 1, the heat insulating member 2, the induction heating coil 3, and the yoke 4 are arranged in this order from the radially inner side toward the radially outer side when viewed from the upper side of the induction heating apparatus 100. In the following description, the vertical direction of the induction heating apparatus 100 is defined as the Z direction, the radial direction of the induction heating apparatus 100 is defined as the R direction, and the circumferential direction of the induction heating apparatus 100 is defined as the C direction. The upper side (upper side) is defined as the Z1 direction (Z1 side), the lower side (lower side) is defined as the Z2 direction (Z2 side), the radially inner side is defined as the R1 side, and the radially outer side (outer peripheral side) is defined as the R2 side.

As shown in fig. 1, the furnace body 1 is configured as a cup-shaped container having an opening at the upper side (Z1 side), and the metal material 10 can be poured into the inside. The furnace body 1 is made of a member having fire resistance. As shown in fig. 2, the furnace body 1 has a side wall 1a having a substantially circular ring shape as viewed from the upper side (Z1 side) in a state where the metal material 10 is charged therein.

The heat insulating member 2 is disposed on the outer peripheral side (R2 side) of the furnace body 1. The heat insulating member 2 is configured to insulate the furnace body 1 disposed on the inner side (R1 side) in the radial direction of the heat insulating member 2 from the induction heating coil 3 disposed on the outer side (R2 side) in the radial direction of the heat insulating member 2. The heat insulating member 2 has a substantially annular shape substantially concentric with the side wall 1a of the furnace body 1 as viewed from the upper side (Z1 side). As shown in fig. 3, the heat insulating member 2 is disposed on the outer peripheral side of the furnace body 1 over substantially the entire area in the vertical direction (Z direction).

As shown in fig. 1, the induction heating coil 3 is disposed so as to be wound around the outer peripheral side (R2 side) of the heat insulating member 2 (i.e., the outer peripheral side of the furnace body 1). That is, as shown in fig. 2, the induction heating coil 3 is disposed so as to be substantially concentric with the side wall 1a of the furnace body 1 when viewed from above (Z1 side). As shown in fig. 3, the induction heating coil 3 is disposed on the outer peripheral side of the heat insulating member 2 (i.e., on the outer peripheral side of the furnace body 1) over substantially the entire vertical direction (Z direction).

The induction heating coil 3 is configured to heat the metal material 10 inside the furnace body 1 by induction heating. Specifically, the induction heating coil 3 is connected to an inverter device (not shown), and an alternating current is supplied from the inverter device to the induction heating coil 3. When an alternating current is supplied to the induction heating coil 3, an eddy current is generated in the metal material 10 disposed inside the furnace body 1 (on the R1 side) inside the induction heating coil 3 by the action of electromagnetic induction. Then, the metal material 10 is heated by joule heat generated along with the eddy current.

As shown in fig. 2, a plurality of yokes 4 are arranged along the outer peripheral side (R2 side) of the induction heating coil 3. The plurality of yokes 4 are arranged at substantially equal intervals from each other along a circle substantially concentric with the induction heating coil 3, respectively, as viewed from the upper side (Z1 side). As shown in fig. 3, the yoke 4 is disposed on the outer peripheral side of the induction heating coil 3 over substantially the entire vertical direction (Z direction). That is, the yoke 4 restricts the movement of the induction heating coil 3 to the outer side in the circumferential direction (R2 side).

The yoke 4 is formed of a plurality of (silicon) steel plates stacked in the circumferential direction (C direction). By disposing the yoke 4 on the outer peripheral side (R2 side) of the induction heating coil 3, leakage of magnetic flux generated during induction heating to the outside (radially outside (R2 side)) is suppressed.

As shown in fig. 1, the yoke support plates 5 are disposed on both sides of the yoke 4 in the circumferential direction (C direction). As shown in fig. 3, the yoke support plate 5 is disposed over substantially the entire area in the vertical direction (Z direction). As shown in fig. 1, the yoke support plate 5 is fixed by sandwiching the yoke 4 formed by laminating silicon steel plates from both sides in the circumferential direction.

Specifically, in the induction heating device 100, through holes (not shown) are formed in the yoke support plate 5 and the yoke 4 at positions corresponding to each other when the yoke 4 is sandwiched by the yoke support plate 5. The yoke support plate 5 is configured to fix the yoke 4 (formed by stacking steel plates) sandwiched therebetween by tightening bolts (not shown) that penetrate through holes of the yoke support plate 5 and through holes of the yoke 4 and nuts (not shown) that are screwed to the bolts.

The cooling water circulation pipe 6 is configured to circulate low-temperature water therein. The cooling water circulation pipe 6 is disposed so as to pass through the vicinity of the induction heating coil 3, and the temperature rise of the induction heating coil 3 is suppressed by cooling with low-temperature water passing through the cooling water circulation pipe 6.

The furnace bottom member 7 is disposed below the furnace body 1 (on the Z2 side) to support the furnace body 1. The hearth member 7 is made of castable refractory (refractory concrete).

The upper refractory member 8 is disposed above (on the Z1 side) the induction heating coil 3 and the yoke 4. The upper refractory member 8 is disposed so as to be substantially concentric with the induction heating coil 3 when viewed from above (Z1 side). The upper refractory member 8 is made of a castable refractory (refractory concrete).

The outer frame member 9 is disposed on the outer peripheral side (R2 side) of the yoke 4. The outer frame member 9 is made of metal. The outer frame member 9 is formed of a plurality of plate-like members and constitutes a housing of the induction heating apparatus 100.

As shown in fig. 3, in the induction heating apparatus 100, a leg portion 100a is provided on the lower side (Z2 side) of the hearth member 7. The leg portion 100a is disposed so as to support the lower end of the outer frame member 9. The leg portion 100a includes a plurality of columnar members, and the operator 20 (see fig. 3) is configured to be able to enter the lower side (Z2 side) of the hearth member 7 from the outer side (R2 side) of the leg portion 100 a.

Here, in the present embodiment, as shown in fig. 1, the induction heating device 100 includes the pressing portion 11, and the pressing portion 11 is provided to extend in the radial direction (R direction) from the yoke support plate 5 so as to contact the induction heating coil 3 from the upper side (Z1 side). Specifically, the pressing portion 11 and the yoke support plate 5 are arranged in a substantially inverted L shape such that the pressing portion 11 extends in a radial direction from an upper end portion 5a of the yoke support plate 5 extending in the vertical direction (Z direction). The pressing portion 11 is provided integrally with the yoke support plate 5.

Specifically, as shown in fig. 4, the pressing portion 11 is a part of the yoke support plate 5 so as to extend from an upper end 5a (Z1 side) of the yoke support plate 5 to the inner side (R1 side) in the radial direction (R direction). Therefore, the yoke support plate 5 has a substantially inverted L-shape formed by the yoke support plate 5 extending in the vertical direction (Z direction) and the pressing portion 11 extending inward in the radial direction, as viewed in the circumferential direction (C direction).

In the radially inner portion of the pressing portion 11, the lower surface 11a (on the Z2 side) contacts the upper end 3a (on the Z1 side) of the induction heating coil 3 from above. As shown in fig. 2, the pressing portion 11 has a substantially flat plate shape. That is, the pressing portion 11 is provided so as to extend in the circumferential direction (C direction) in addition to the radial direction (R direction). As shown in fig. 1, the pressing portion 11 has a shape surrounded by a pair of sides extending in the radial direction and a pair of sides extending in the circumferential direction when viewed from the upper side (Z1 side). This can increase the area of the pressing portion 11 in contact with the induction heating coil 3, as compared with the case where the pressing portion 11 is provided so as to extend only in the radial direction. Further, in the induction heating apparatus 100, the pressing portions 11 are provided on all the yoke support plates 5 provided on both sides in the circumferential direction with respect to the plurality of yokes 4, respectively. As shown in fig. 4, a rib 11b is provided at a boundary portion between the yoke support plate 5 and the pressing portion 11, which are formed in a substantially inverted L shape.

In the present embodiment, the induction heating apparatus 100 includes the fastening member 12, and the fastening member 12 is disposed on the lower portion 5b of the yoke support plate 5 and presses the induction heating coil 3 from the upper side (Z1 side) to the lower side (Z2 direction) via the pressing portion 11 with fastening force.

Specifically, the yoke support plate 5 is fixed to the hearth member 7 at the lower portion 5b of the yoke support plate 5 by the fastening members 12. The fastening member 12 is disposed so as to straddle the lower portion 5b of the yoke support plate 5 and the hearth member 7, and is configured to fasten and fix the lower portion 5b of the yoke support plate 5 and the hearth member 7. The pressing portion 11 is configured to press the induction heating coil 3 from the upper side (Z1 side) downward (Z2 direction) by a fastening force generated by the fastening member 12.

Specifically, a fastening portion 5c for fastening and fixing the fastening member 12 is provided integrally with the yoke support plate 5 at the lower portion 5b of the yoke support plate 5. Further, the fastening portion 5C has a substantially U-shape as viewed in the circumferential direction (C direction). The tightening portion 5c is disposed so that the substantially U-shaped bottom portion is the upper side (Z1 side).

The fastening member 12 includes a bolt portion 12a and a nut portion 12 b. In the present embodiment, the bolt portion 12a is configured such that the head portion 12c is connected to the lower portion 5b of the yoke support plate 5 and the leg portion 12d penetrates the hearth member 7. Specifically, the bolt portion 12a is provided such that the head portion 12c abuts against the upper surface (Z1 side) of the bottom portion of the substantially U-shaped fastening portion 5c and the leg portion 12d penetrates through the through hole formed in the bottom portion of the fastening portion 5c, the through hole formed in the floor member 7, and the through hole formed in the portion 9a of the outer frame member 9 (where the lower surface 7a of the floor member 7 contacts from above). The nut portion 12b is provided to be screwed to a leg portion 12d of the bolt portion 12a that penetrates below (on the Z2 side) the portion 9a of the outer frame member 9 (i.e., below the floor member 7). That is, in the present embodiment, the fastening member 12 is exposed below the hearth member (on the Z2 side).

In this state (in a state where the head portion 12c is connected to the fastening portion 5c and the nut portion 12b is screwed to the bolt portion 12a of the portion 9a where the leg portion 12d penetrates the oven bottom member 7 and the outer frame member 9), the lower portion 5b of the yoke support plate 5 is brought closer to the upper surface 7b of the oven bottom member 7 by screwing the nut portion 12b to the leg portion 12d of the bolt portion 12a so that the nut portion 12b is brought closer to the lower surface 7a of the oven bottom member 7 (the lower surface of the portion 9a of the outer frame member 9). Accordingly, the yoke support plate 5 moves downward (Z2 side), and the pressing portion 11 provided integrally with the yoke support plate 5 presses the induction heating coil 3 downward (Z2 direction) from the upper side (Z1 side).

In the present embodiment, the fastening member 12 includes a spring member 12 e. Specifically, the spring member 12e has a through hole through which the leg portion 12d of the bolt portion 12a is inserted. The spring member 12e is provided between the lower surface 7a of the hearth member 7 and the nut portion 12b in a state where the leg portion 12d of the bolt portion 12a is inserted through the through hole. In the induction heating device 100, a plurality of disc springs are provided as the spring members 12e in a stacked state.

(effects of the embodiment)

In the present embodiment, the following effects can be obtained.

In the present embodiment, as described above, the induction heating apparatus 100 includes: a pressing portion 11 provided to extend in a radial direction (R direction) from the yoke support plate 5 so as to contact the induction heating coil 3 from an upper side (Z1 side); and a fastening member 12 disposed on the lower portion 5b of the yoke support plate 5 and pressing the induction heating coil 3 from the upper side to the lower side (Z2 direction) via the pressing portion 11 by a fastening force. Thus, since the fastening member 12 that presses the induction heating coil 3 downward from above via the pressing portion 11 by a fastening force is disposed on the lower portion 5b of the yoke support plate 5, the worker can perform the fastening operation of the fastening member 12 on the lower portion of the induction heating apparatus 100 and perform the fixing operation of the member (pressing portion 11) that presses the induction heating coil 3 downward from above via the yoke support plate 5 with respect to the induction heating apparatus 100. As a result, the position at which the work of pressing the member (pressing portion 11) of the induction heating coil 3 downward from the upper side is performed is a relatively low position that the worker 20 (see fig. 3) can easily reach directly from the installation surface 21 (see fig. 3) of the induction heating apparatus 100, and therefore, when the work of pressing the member of the induction heating coil 3 downward from the upper side is performed, the reduction in workability can be suppressed.

In the present embodiment, as described above, the induction heating apparatus 100 includes the base member 7, and the base member 7 is disposed on the lower side (Z2 side) of the furnace body 1. The yoke support plate 5 is fixed to the furnace bottom member 7 by a fastening member 12 at the lower portion 5b of the yoke support plate 5. Thus, the yoke support plate 5 is fixed to the furnace bottom member 7 disposed below the furnace body 1 by the fastening members 12 at the lower portion 5b of the yoke support plate 5, and therefore, the fastening positions of the fastening members 12 can be reliably disposed below the induction heating apparatus 100. As a result, the worker 20 (see fig. 3) can reliably perform the work on the fastening member 12 at the lower portion of the induction heating apparatus 100. Further, a pressing force for pressing the induction heating coil 3 downward (in the Z2 direction) from the upper side (the Z1 side) can be generated by the fastening force of the fastening member 12 to the hearth member 7.

In the present embodiment, as described above, the fastening member 12 is disposed so as to straddle the lower portion 5b of the yoke support plate 5 and the hearth member 7, and the lower portion 5b of the yoke support plate 5 is fastened and fixed to the hearth member 7. The pressing portion 11 is configured to press the induction heating coil 3 downward (Z2 direction) from the upper side (Z1 side) by a fastening force generated by the fastening member 12. Thus, since the fastening members 12 are disposed so as to straddle the lower portion 5b of the yoke support plate 5 and the furnace bottom member 7, even when the yoke support plate 5 does not reach the furnace bottom member 7, the lower portion 5b of the yoke support plate 5 and the furnace bottom member 7 can be fastened and fixed by the fastening members 12.

In the present embodiment, as described above, the fastening member 12 is configured to include the bolt portion 12a, the nut portion 12b, and the spring member 12 e. The bolt portion 12a is configured such that the head portion 12c is connected to the lower portion 5b of the yoke support plate 5 and the leg portion 12d penetrates the hearth member 7. The nut portion 12b is screwed to a leg portion 12d of the bolt portion 12a that penetrates below (on the Z2 side) the hearth member 7. Further, the spring member 12e is provided between the lower surface 7a of the hearth member 7 and the nut portion 12 b. Thus, even when the height position of the induction heating coil 3 pressed by the pressing portion 11, the height position of the yoke 4, the length of the yoke support plate 5, and the like do not match (have a deviation in accuracy), the above-described deviation in accuracy can be absorbed by the expansion and contraction of the spring member 12e provided between the lower surface 7a of the hearth member 7 and the nut portion 12 b. As a result, the pressing force generated by the fastening member 12 due to the above-described variation in accuracy can be suppressed from becoming uneven in the circumferential direction (C direction) of the induction heating coil 3.

In the present embodiment, as described above, the fastening member 12 is configured to be exposed below the hearth member 7 (on the Z2 side). Thereby, the worker 20 (see fig. 3) can reach the fastening member 12 below the hearth member 7 where the fastening member 12 is exposed. As a result, as compared with the case where the fastening member 12 is not exposed below the hearth member 7, when the member (pressing portion 11) that presses the induction heating coil 3 downward (Z2 direction) from the upper side (Z1 side), the reduction in workability can be further suppressed.

In the present embodiment, as described above, the pressing portion 11 and the yoke support plate 5 are arranged in a substantially inverted L shape such that the pressing portion 11 extends in the radial direction (R direction) from the end portion 5a on the upper side (Z1 side) of the yoke support plate 5 extending in the vertical direction (Z direction). Accordingly, since the pressing portion 11 and the yoke support plate 5 are arranged in a substantially inverted L shape, the pressing portion 11 does not protrude upward (Z1 side) from the yoke support plate 5. That is, the upper sides of the yoke support plate 5 and the pressing portion 11 are relatively flat. As a result, since the molded castable refractory can be used on the upper side of the yoke support plate 5 with the yoke 4 sandwiched from both sides in the circumferential direction (C direction) (japanese patent application No.: molding キャスタブル), the time required for replacing the castable refractory (i.e., the time during which the apparatus cannot be used (downtime)) can be shortened as compared with the case where the castable refractory needs to be used in the process of disassembling, pouring, and drying each time the castable refractory is replaced (japanese patent application No.: flow し Write み キャスタブル).

In the present embodiment, as described above, the pressing portion 11 is formed integrally with the yoke support plate 5. This can reduce the number of parts and simplify the device structure, as compared with the case where the pressing part 11 is provided as a separate member from the yoke support plate 5.

[ modified examples ]

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the claims rather than the description of the above embodiments, and the present invention includes all modifications (variations) within the meaning and scope equivalent to the claims.

For example, in the above-described embodiment, the pressing portion 11 is provided integrally with the yoke support plate 5, but the present invention is not limited thereto. In the present invention, the pressing portion may be provided independently of the plate member.

In the above-described embodiment, the example in which the pressing portion 11 has a shape surrounded by a pair of sides extending in the radial direction (R direction) and a pair of sides extending in the circumferential direction (C direction) when viewed from the upper side (Z1 side) is shown, but the present invention is not limited to this. In the present invention, for example, the pressing portion may be configured to have a shape surrounded by a pair of sides extending so that a distance from the outer side to the inner side in the radial direction becomes larger and a pair of sides extending in the circumferential direction when viewed from the upper side. In this case, since the width of the inner side in the radial direction (the length in the circumferential direction) of the pressing portion is larger than the width of the outer side in the radial direction, the area in which the induction heating coil is pressed from above by the pressing portion can be increased.

In the above-described embodiment, the pressing portion 11 and the yoke support plate 5 are arranged in the substantially inverted L shape so that the pressing portion 11 extends in the radial direction (R direction) from the upper end portion 5a (Z1 side) of the yoke support plate 5 extending in the vertical direction (Z direction). In the present invention, the pressing portion 11 and the yoke support plate 5 may be arranged in a shape other than a substantially inverted L shape such as a substantially T shape or a substantially cross shape.

In the above-described embodiment, the fastening member 12 is configured to be exposed below the hearth member 7 (on the Z2 side), but the present invention is not limited to this. In the present invention, the fastening member may be exposed laterally or upwardly of the hearth member.

In the above-described embodiment, the example in which the disc spring is provided as the spring member 12e is shown, but the present invention is not limited to this. In the present invention, a spring member other than a belleville spring such as a coil spring may be provided.

In the above embodiment, the fastening member 12 is configured to include the spring member 12e provided between the lower surface 7a of the hearth member 7 (and the portion 9a of the outer frame member 9) and the nut portion 12b, but the present invention is not limited to this. In the present invention, the fastening member may be configured not to include the spring member.

In the above embodiment, the example has been described in which the fastening member 12 includes the bolt portion 12a and the nut portion 12b, the bolt portion 12a is configured such that the head portion 12c is connected to the lower portion 5b of the yoke support plate 5, the leg portion 12d is inserted through the hearth member 7, and the nut portion 12b is configured such that it is screwed to the leg portion 12d of the bolt portion 12a inserted below (on the Z2 side) the hearth member 7. In the present invention, the bolt portion may be configured such that the head portion is disposed below the hearth member and the leg portion penetrates the hearth member and is connected to the lower portion of the hearth member, and the nut portion may be configured to be screwed to the leg portion of the bolt portion penetrating the upper portion of the hearth member.

In the above embodiment, the yoke support plate 5 is fixed to the hearth member 7 by the fastening members 12 at the lower portion 5b of the yoke support plate 5. In the present invention, the yoke support plate may be fixed to a member other than the hearth member by using a fastening member.

In the above embodiment, the example in which the pressing portions 11 are provided on all the yoke support plates 5 provided on both sides in the circumferential direction with respect to the plurality of yokes 4 has been described, but the present invention is not limited to this. In the present invention, the pressing portion may be configured to be provided on all yoke support plates provided on one side in the circumferential direction with respect to the plurality of yokes. Further, the pressing portion may be configured as a part of the yoke support plate provided on each of the plurality of yokes on both sides in the circumferential direction.

In the above-described embodiment, the leg portion 100a including a plurality of columnar members arranged on the lower side (Z2 side) of the floor member 7 is provided, and the operator 20 is configured to be able to enter the lower side (Z2 side) of the floor member 7 from the outside (R2 side) of the leg portion 100a, but the present invention is not limited to this. In the present invention, as long as the operator can enter the lower side of the hearth member, for example, the floor member may be configured to be provided with a leg portion other than the leg portion including a plurality of columnar members, such as a cylindrical leg portion having a hollow side wall formed therein with an opening through which the operator can pass. Further, a recessed portion (Japanese character: recess り Write み) may be formed in the installation surface on which the induction heating device is installed so as to be able to enter the lower side of the hearth member.