JP2673731B2 - Electromagnetic induction heating device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electromagnetic induction heating device for heating a continuous thin plate by electromagnetic induction.

(Prior Art) This type of electromagnetic induction heating device is a device for performing electromagnetic induction heating by supplying a thin plate at a constant speed so as to pass between magnetic poles facing each other, and is disclosed in, for example, Japanese Patent Publication No. 63-27836. It is disclosed. Briefly, a plurality of magnetic pole segments arranged in parallel to each other in the width direction of the thin plate and facing the thin plate, and each of these magnetic pole segments in the thickness direction of the thin plate and other magnetic pole segments are A drive mechanism for moving independently, a common coil arranged so as to surround a plurality of magnetic pole segments, and a non-magnetic metal that is provided so as to be retractable in the width direction of the thin plate and adjusts the magnetic field from the magnetic pole segments. And a movable shield plate. This device has the feature that it can easily deal with changes in the dimensions of the thin plate, and that it can quickly adjust the temperature distribution in the width direction of the thin plate.

(Problems to be Solved by the Invention) However, in the above-described electromagnetic induction heating device, when a thin plate is warped, the warped portion may come into contact with the magnetic pole segment and the thin plate may be flawed. If the gap between the magnetic pole segments facing each other is increased in order to prevent the occurrence of such a flaw, the heating efficiency will deteriorate.

Further, in the longitudinal magnetic flux type electromagnetic induction heating device, when the thin plate is a ferromagnetic material, the ferromagnetic thin plate is attracted to the magnetic poles, so that the ferromagnetic material cannot be heated.

In view of the above problems, a technical problem of the present invention is to provide an electromagnetic induction heating device capable of eliminating the warp of a thin plate in the device.

Another object of the present invention is to provide an electromagnetic induction heating device capable of processing both a thin plate made of a ferromagnetic material and a thin plate made of a non-magnetic material.

The present invention further seeks to provide an electromagnetic induction heating device capable of reducing the distance between opposing magnetic poles.

(Means for Solving the Problem) According to the present invention, magnetic poles are arranged in a moving path of a thin plate sent in a predetermined direction so as to face each other with the thin plate in between, and the thin plate is heated by electromagnetic induction. In the electromagnetic induction heating device, a roll for guiding a thin plate is arranged between the opposing magnetic poles, and the roll is made of a ferromagnetic material.

At least one of the roll and the magnetic pole is preferably movable in the plate thickness direction of the thin plate so that the distance between the magnetic pole and the roll is variable.

(Operation) The roll in the present invention acts to prevent the thin plate from warping in the width direction by being in contact with the thin plate over the entire width. Since the roll is made of a ferromagnetic material, the magnetic pole distance does not increase even if the magnetic poles are opposed to each other. On the contrary, it is not necessary to consider the warpage of the thin plate, so that the magnetic pole and the thin plate are sufficiently close to each other. be able to.
Furthermore, the roll also has a function of giving a predetermined tension to the thin plate, and as a result, the roll acts to keep the thin plate in a restrained state with respect to the movement in the thickness direction,
Even a thin plate made of a ferromagnetic material will not be attracted to the magnetic pole.

(Examples) Examples of the present invention will be described below.

Referring to FIG. 1, the electromagnetic induction heating device according to the present invention includes magnetic poles 21 and 31 arranged to face each other. These magnetic poles 21 and 31 are connected in series along the moving direction of the thin plate 1 described later, respectively, to coils 22a to 22d and 32a to 32d, respectively.
Rolls 4a to 4d for guiding the conveyance of the thin plate 1 are arranged between the magnetic poles 21 and 31, and the thin plates 1 are guided in a zigzag manner on the rolls 4a to 4d.

Referring to FIG. 2, the magnetic poles 21 and 31 are each a plurality of magnetic pole segments arranged in parallel in the width direction of the thin plate 1.
It consists of 21m and 31m, and coils 22a and 32a are wound so as to surround these magnetic pole segments.

Referring to FIG. 3, the roll 4 is made of a ferromagnetic material, for example, a laminated body of silicon steel plates, and a hollow shaft 42 made of a non-magnetic material such as stainless steel (SUS) is passed through the center of the roll member 41. A heat insulating coating layer 43 made of a heat resistant material such as Teflon is provided on the outer periphery. Further, the hollow shaft 42 allows the refrigerant to pass when it is necessary to cool the roll 4. Further, the magnetic pole roll 4 may be provided in a floating state, but may be rotationally driven in synchronization with the transport speed of the thin plate 1.

Further, the length of the magnetic pole roll member 41 is set to be larger than the width dimension of the thin plate 1, so that the warp of the thin plate 1 in the width direction in the apparatus can be prevented.

In FIG. 1, when the roll member 41 is made of a ferromagnetic material, the distance between the magnetic poles facing each other is represented by D. Since each roll plays the role of a yoke in the magnetic circuit, when viewed magnetically. The distance between the magnetic poles is (l ₁ + l ₂ ). However, l ₁ is the distance between the roll and the magnetic pole which are in contact with the thin plate 1, and l ₂ is the distance between the roll and the magnetic pole on the side opposite to the distance l ₁ . As a result of the warp of the thin plate 1 in the width direction being prevented, the distances l ₁ and l ₂ can be reduced to the extent that the thin plate 1 and the magnetic poles do not come into contact with each other. As a result, the magnetic pole-to-pole distance (l ₁ + l ₂ ) can be greatly reduced as compared with the conventional pole-to-pole distance D in which no roll is installed.

Further, since the heating efficiency for the thin plate 1 increases as the magnetic pole-to-pole distance (l ₁ + l ₂ ) decreases, according to the present invention, the heating efficiency can be increased as compared with the conventional one.

Further, the thin plate 1 is bridged in a state where tension is applied to the rolls 4a to 4d, whereby the thin plate 1 is kept in a state in which its displacement in the thickness direction is restrained.
As a result, even if the thin plate 1 is a ferromagnetic material, it will not be attracted to the magnetic poles. Therefore, since the electromagnetic induction heating device according to the present invention can also heat the ferromagnetic thin plate,
For example, in the case of stainless steel, since there are non-magnetic type and ferromagnetic type, it has conventionally been necessary to properly use the vertical magnetic flux type and the transverse magnetic flux type. Is unnecessary. Further, the magnetic characteristics of the ferromagnetic material greatly fluctuate at its own Curie point, but in the apparatus according to the present invention, heating may be performed so as to cross the Curie point without considering such fluctuations in the magnetic characteristic. it can.

The present invention can be variously modified. For example, although each roll is placed at a fixed position between the two magnetic poles in the embodiment, it may be provided so that the position can be adjusted in the thickness direction of the thin plate 1. For example, the distance l ₂ is fixed for each magnetic pole, and the roll and the magnetic pole facing it are integrally movable so that the distance l ₁ can be adjusted arbitrarily, or the position of the roll is fixed and the magnetic pole is fixed. It is conceivable to use a method that makes it possible to move.

Further, it is not necessary to arrange the rolls between all the magnetic poles of the plurality of sets, and the thin plates are not limited to the zigzag shape shown in the drawing.

Further, the structure of the magnetic poles is not limited to the one shown in the figure, and the magnetic poles are independent of each other, or the magnetic poles are integrated and can be displaced by one driving source. Various well-known structures such as can be applied.

(Effects of the Invention) As described above, according to the present invention, by disposing the roll made of a ferromagnetic material for guiding the thin plate between the magnetic poles facing each other with the thin plate in between, the width direction of the thin plate can be reduced. Since the warpage can be prevented, the distance between the thin plate and the magnetic pole can be made smaller than that of the conventional one, and thus the heating efficiency for the thin plate can be improved. Also,
The material of the thin plate may be either non-magnetic or ferromagnetic, which allows the supply line of the thin plate to be used for both non-magnetic material and ferromagnetic material.

[Brief description of the drawings]

FIG. 1 is a schematic structural diagram of an electromagnetic induction device according to the present invention, and FIG.
1 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a perspective view of the roll shown in FIG. In the figure, 1 is a thin plate, 4 and 4a to 4d are rolls, 21 and 31 are magnetic poles, and 22a to 22.
d, 32a to 32d are coils, 41 is a roll member, 42 is a hollow shaft, and 43 is a heat insulating coating layer.

Claims (2)

(57) [Claims] 1. An electromagnetic induction heating apparatus for heating a thin plate by electromagnetic induction by arranging magnetic poles so as to face each other across the thin plate in a moving path of the thin plate sent in a predetermined direction. An electromagnetic induction heating device comprising a roll for guiding the thin plate, the roll being made of a ferromagnetic material, between the magnetic poles facing each other. 2. The electromagnetic induction heating device according to claim 1, wherein at least one of the roll and the magnetic pole is movable so that a distance between the magnetic pole and the roll is variable.