JPH02155193A - Coil device for induction heating - Google Patents

Abstract

PURPOSE:To prevent a coil for induction heating from being cracked due to thermal expansion by composing the coil of the first and second members and also composing the second member of aggregate of small piece of members. CONSTITUTION:A wall lining material is composed of at least two kinds of members that the first member 13 of preferable electric insulation fixed to a heating coil 12 and the second member 14 of heat and abrasion resistance disposed in the first member 13. The second member 14 is composed of aggregate of small piece of members such as a small piece of holding member 14b and a member 14a to be held. By composing the second member 14 of the aggregate of small piece of members, there is no effect of thermal expansion even if the second member 14 is heated when an object to be heated is heated. Therefore, a coil for induction heating is prevented from being cracked.

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to an induction heating coil device.

B0 Summary of the Invention This invention provides an induction heating coil device in which a heating coil is provided with a lining material, the lining material is composed of at least two types of members, and the first member on the side of the heating coil has good electrical insulation. The second member provided on the first member is made of a small piece and has good heat resistance and abrasion resistance. , the occurrence of cracks due to thermal expansion is eliminated.

C8 PRIOR TECHNOLOGY FIG. 3 is a schematic diagram of an apparatus for heating a thin plate being conveyed in an induction heating furnace. In FIG. It is conveyed from the right side to the left side in the figure by a conveying device (not shown). 3 and 4 are guide rolls provided on the inlet and outlet sides of the induction heating furnace 5, and 5a and 5b are placed on both sides of the thin plate 1.

This is a heating coil located below. The thin plate l is guided by the guide rolls 3 and 4 while heating coils 5a and 5
induction heating occurs while passing between b.

When inductively heating a thin plate l, the smaller the gap between the heating coil and the thin plate that is the object to be heated, the more efficiently induction heating can be achieved, so it is preferable that the gap g between the upper and lower heating coils be as small as possible. .

Further, the thin plate 1 being transported may oscillate during transport or may be deformed due to temperature rise due to induction heating.

Therefore, when the thin plate 1 passes through the induction heating furnace 5, if the thin plate 1 contacts or slides on the heating coils 5a and 5b, an electrical short circuit may occur or damage to the heating coil may occur. .

In order to prevent the heating coil from being damaged or short-circuited as described above, and to protect the insulating layer formed on the outer surface of the conductor of the heating coil, a heat insulating board is placed as a lining material on the inner surface of the heating coil to protect the heated object. It is provided between the thin plate.

FIG. 4 shows an example of the heat-insulating sliding plate 7 as the above-mentioned lining material.
This is a perspective view showing a main part of an induction heating device equipped with a heat insulating sliding plate 7 made of a heat-resistant electrical insulating material. If the heating coils 5a + 5b are configured in this way, the thin plate l
Even if the heating coils 5a and 5 are in sliding contact with the heat insulating sliding plate 7,
No more contact with b. Note that the heating coils 5 a + 5 b shown in FIG. 4 operate as a pair of transverse magnetic flux type heating coils.

FIG. 5 shows an example of a longitudinal magnetic flux type heating coil, and the same parts as in FIG. 3 are denoted by the same reference numerals. In this way, the longitudinal magnetic flux type and the transverse magnetic flux type are used as appropriate depending on the material and thickness of the thin plate.

6 and 7 are cross-sectional views of the induction heating furnace 5 shown in FIGS. 4 and 5, in which a heat insulating sliding plate 7 is shown in FIG. In FIG. 7, an insulating material 8 and a heat insulating sliding plate 7 are provided. In addition, the heating coils 5a, 5b and the thin plate l illustrated in FIGS. 5 and 7
The reason why the insulating material 8 and the heat insulating sliding plate 7 are provided between them is as follows.

(a) If only the heat insulating sliding plate 7 is used as shown in FIG. 6, this is to prevent water droplets from falling onto the thin plate 1 at the start of heating and causing uneven heating on the thin plate. .

(b) Furthermore, by providing the heat insulating sliding plate 7 and the insulating material 8, the excellent properties of both can be utilized. That is, the heat insulating sliding plate 7 has good heat resistance and hardness, and the insulating material 8 has good electrical insulation, so by combining the two, a material with high heat resistance, abrasion resistance, and insulation can be obtained. Because you can get it.

As the above-mentioned heat-insulating sliding plate, a ceramic member is generally used in many cases because of the above-mentioned properties.

D0 Problems to be Solved by the Invention The induction heating furnace 5 shown in FIGS. 4 to 7 equipped with the above-mentioned heat-insulating sliding plate 7 also has the following problems.

That is, the heat insulating sliding plate 7 shown in FIGS. 4 to 7 has conventionally been made of a large-area plate (for example, one plate for each of the upper and lower sides). For this reason, the heat load applied to each part of the heat-insulating sliding plate 7, that is, the temperature rise in each part due to the heat from the thin plate 1, which is the object to be heated, is not uniform, and there are quite large differences. As a result, large thermal stress is generated locally, and repeated stress tends to cause damage such as cracks. This is because since there is only one heat-insulating sliding plate, it is difficult for thermal expansion to escape and cracks are likely to occur. In particular, when a ceramic plate or the like having a large area is used for the heat insulating sliding plate, cracking is likely to occur due to thermal shock or thermal stress.

Furthermore, if the heat insulating sliding plate 7 is damaged, its fragments may fall as foreign matter onto the thin plate that is the object to be heated, causing a problem of causing flaws on the conveying roller surface or the surface of the thin plate. In particular, when the above-mentioned problems occur during the manufacture of cladding plates, there is a risk that serious defects may occur in the cladding plates.

In addition to the above, since the area of the heat insulating sliding plate 7 is large, there is also the problem that it is not easy to replace it when it is damaged.

An object of the present invention is to provide an induction heating coil device in which a heat insulating sliding plate is formed into small pieces to create relief due to thermal expansion and prevent cracking.

E1 Means for Solving the Problems The present invention provides an induction heating device for heating a metal thin plate-shaped object being conveyed by passing it through a heating coil provided with a lining material inside, wherein the lining material is a heating coil. The second member is composed of at least two types: a first member fixed to and having good electrical insulation properties, and a second member provided inside the first member and having heat resistance and wear resistance. is constructed from a collection of small pieces of wood.

Further, the second member is composed of a small piece-shaped holding material and a held material.

F3 action Since the second member is constituted by an assembly of small pieces of material, even if the second member is heated during heating of the object to be heated, the influence of thermal expansion is small, so no cracking occurs.

G. Example An embodiment of the present invention will be described below based on the drawings.

1A, B, and C show a first embodiment, and this embodiment shows a transverse magnetic flux heating method. FIG. 1A is a partially sectional front view, and FIG. 1B is a 1 is a plan view with the upper coil section removed as viewed from the /l-A line in Figure 1.
Figure C is a side sectional view taken along the line CC in Figure 1B.

In FIGS. 1A, B, and C, a thin plate 11, which is an object to be heated, is configured to be conveyed between upper and lower heating coils 12, 12 in a direction perpendicular to the plane of the paper.

A heat insulating sliding plate 14.14, which is a second member, is attached to the heated object side of the heating coil 12.12 with an electric insulating plate 13.13, which is a first member, in between. Heat insulation sliding plate 1
4.14, for example, are small pieces of heat insulating sliding plates 14a, 14a that serve as held members of about 150 x 150 xi, and a heat insulating sliding plate 14b that serves as a holding material for attaching these sliding plates 14a, 14a to the heating coil 12.12; 14b.

The heating coil 12.12 is formed of coil conductors 12a, 12a having cooling water holes 15, 15, and plates 12b, I, 2b are integrally attached and fixed to the coil conductors 12a, 12a. Note that tap holes are bored at predetermined positions in the plate materials 12b, 12b. This plate material 12b
, t2b, holes are also bored in the insulating plates 13.13 and the insulating sliding plates 14b, 14b which serve as holding members. Further, the heat insulating sliding plates 14b, 14b are also provided with a recessed portion for accommodating Holt's head.

Then, as shown in FIG. 1A, the insulating sliding plates +4b and 14b are mounted with the insulating plates 13°13 in between, and the insulating plates 13 , 13 and a heat insulating sliding plate 14a,
14a and 14b.

14b is attached to the heating coil 12.12. In this way, the heat insulating sliding plates 14a, 14a are attached to the protrusions 17.17 formed on the heat insulating sliding plates 14b, 14b as holding members.
It is configured to be movably held by. Therefore, the heat insulating sliding plate 14a.

Even if 14a expands due to thermal expansion or the like, the expansion is sufficiently absorbed.

Note that the heat insulating sliding plates 14b and +4b, which serve as holding members, are selected from members that have sufficient strength and strength against thermal shock.
A may be made of a material that does not have that much strength. By forming the heat insulating sliding plate into small pieces in this manner, there is an advantage that the material of the sliding plate can be used appropriately. On the other hand, the insulating plates 13.13 do not receive heat directly from the heated object 11, which becomes hot, and are cooled by cooling water circulating through the heating coils 12.12, so an insulating material made of resin or the like is used. Thus, one or several large-area insulating plates can be formed.

In the above embodiment, as means for attaching the insulating plate 13.13 and the insulating sliding plate 14.14 to the heating coil 12,
Plate materials 12b, 12 attached to coil conductors 12a, 12a
The bolts 16 and 16 are screwed into the tapped holes provided in the coil conductor 12H, as shown in the first diagram.
A protrusion 18 having a tapped hole may be provided at a predetermined location on the side surface of the holder for attachment.

Next, the second embodiment will be described with reference to FIGS. 2A, B, and C. The same parts as in the first embodiment are designated by the same reference numerals.

In FIGS. 2A, B, and C, the heat insulating sliding plate 14 serving as the second member is only a plurality of sliding plates 14a in the form of small pieces of, for example, about 150 x 150 JU+, and the sliding plate 14a is not attached. A hole and a recess for accommodating the head of a bolt are provided respectively, and the heating coil 12 is directly attached to the heating coil 12 with a bolt 16.16 with an insulating plate 13.13 in between. In this embodiment, the bolt holes provided in the sliding plate 14a are made slightly thicker than the diameter of the bolts, so that thermal expansion can be absorbed. can do.

First mentioned above. In the second embodiment, the case where the heating coil 12°12 is a transverse magnetic flux type heating coil has been described;
The same applies to the lining material of the longitudinal magnetic flux type heating coil 12.12. In addition, as described above, the lining material is used as the first material. Although the explanation has been made using two types of second members, it is also possible to use two types of insulating plates as the first member for a total of three types of members, and furthermore, one of these types of members has water absorbing properties. It may also be used as a member.

1st. As shown in the second embodiment, the lining material is placed in the first. By configuring the structure with the second member, there is an advantage that the first member can be made of a material with good insulation properties, and the second member can be made of a hard ceramic material with high heat resistance, heat insulation, and wear resistance. . Further, in the first embodiment, since the heat insulating sliding plate 14b serving as a holding member is attached to the fill conductor 12a, the radiant heat from the thin plate 11 can be absorbed by water cooling. Therefore, the bolt 16 and the sliding plate 14b
Therefore, a material with high strength can be used for the sliding plate 14b.

H. EFFECTS OF THE INVENTION As mentioned above, according to the present invention, since the second member is made of a small piece-like aggregate, there is an advantage that there is no possibility of cracking in the second member due to thermal expansion. be. In addition, by constructing the second member from a small piece of holding material and a small piece of held material that is expandably and contractibly held by this holding material, cracks due to thermal expansion are less likely to occur in the second member.

Furthermore, since the second member is made of a small piece, it can be easily replaced during repair or maintenance.

[Brief explanation of the drawing]

Figures 1A, B, C, and D show an embodiment of the present invention, with Figure 1A being a partially sectional front view, and Figure 1B being A-A in Figure 1A. A plan view as seen from the line arrows, Figure 1C is the 1st
A side cross-sectional view taken along line C-C in Figure B, the first figure is a cross-sectional view showing different examples of bolt attachment means, and the second figures A, B,
2C shows a second embodiment of the present invention, FIG. 2A is a partially sectional front view, and FIG. 2B is a section taken along A-A in FIG. 2A.
FIG. 2C is a side sectional view taken along the line BB in FIG. 2B, FIGS. 3 to 7 show conventional examples, and FIG. A schematic configuration diagram of an apparatus for heating with an induction heating furnace, and FIGS. 4 and 5 are perspective views showing essential parts of the induction heating apparatus. 11...Thin plate serving as a heated object, 12.12...Heating coil, 12a, 12a--=+il conductor, 12b. 12b...Plate material, 13.13...Insulating plate serving as first member, 14.14...-insulating sliding plate serving as second member, 1
4a, 14a...Insulating sliding plate serving as held material, 14b
,! 4b...Insulating sliding plate serving as a holding material, 16, 16.
··bolt. Outside 2 people Figure 3 Coil ``J pattern (Text's body positive attack Figure 6 Animal Fang $ Rochi n Chihi 1'') - One side 32

Claims (2)

[Claims] (1) In an induction heating device that heats a metal thin plate-shaped object to be heated by passing it through a heating coil provided with a lining material inside, the lining material is an electrically insulating material fixed to the heating coil. It is composed of at least two types: a first member with good quality and a second member that is provided inside the first member and has heat resistance and wear resistance, and the second member is an aggregate of small pieces of material. What is claimed is: 1. A coil device for induction heating characterized by comprising: (2) The second member is composed of a small piece of holding material and a small piece of held material held by this holding material, and the holding material is attached to the heating coil by a fastening member. The induction heating coil device according to claim 1.