JPS5825096A - Induction heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a planar heating type induction heating device for heating objects to be heated, such as slabs, holes, dopplers, or strips in a steel rolling line, by the electromagnetic induction action of an inductor coil. Regarding the inductor coil device, Fig. 1 (4) and Φ) are a front sectional view and a side sectional view showing the inductor coil device of a conventional induction heating device of this type.
is a laminated core constructed by laminating silicon steel plates with a predetermined thickness. As shown in Figure 1, the laminated core has a Water-cooled copper plates (containers) are interposed at predetermined intervals to cool the generated heat, and an inductor coil (wound a predetermined number of times around the center leg (1a) of the laminated core (1)) is used. 3) is composed of a hollow steel tube whose outer surface is insulated and cooling water is allowed to flow inside.(4) contains the laminated core (!) and an inductor coil function. The laminated iron core (1) and the inductor coil (3) are separated from the heat of this heat-resistant concrete (4 is the heated object heated by the electromagnetic induction action of the inductor coil +31). It was established for the purpose of protection.

The above-mentioned induction fill device was described for the case where it was placed facing only the top surface of the object to be heated with a predetermined gap, but in general, a single inductor coil device configured as above is used to connect the object to be heated. (5) It is arranged not only on the upper and lower surfaces but also on both sides of this heated object 1l.
s) from the surroundings at the same time. Then, the inductor coil (3
) The alternating magnetic flux generated by passing a predetermined alternating current through the laminated iron core (1) and the heated object (5) passes through a closed circuit that passes through the heated object (5), causing a vortex generated inside the heated object (5). The temperature of the heated object rises due to Joule heat generated by the current. At this time, the temperature inside the laminated iron core (1) also rises due to Joule heat, but this is cooled by the water-cooled copper plate (2). In addition, the object to be heated at this time (6)
The surface temperature of the heat-resistant concrete (4) is around 1250°O, and the surface temperature of the heat-resistant concrete (4) is 1150'o~1200'
o and is interposed between the object to be heated (5) and the laminated iron core (1) facing the object to be heated (6)) The thickness has a large effect on the electrical efficiency of the inductor coil (°C), so it is limited to within 1a%, and the temperature gradient of the thin facing part (4a) of this heat-resistant concrete (4) with a thickness of 10% is several 109. It also reaches 'O'.

Therefore, although fire-resistant castable, which has good spalling resistance, is widely used as a material for this heat-resistant concrete (4), it still
When the object to be heated (6) is first conveyed to the position of the inductor fill (3), or when the feeding speed of the object to be heated (6) is intermittent, the temperature of the thin opposing portion (4a) of the heat-resistant concrete 14) suddenly increases. Changes to This is because the inductor coil (3) made of a hollow steel pipe through which cooling water flows and the water-cooled copper plate (
3) The heat-resistant concrete IJ -) +4 in contact with this
This is because 1 is partially cooled. If the temperature difference in the heat-resistant concrete (4) increases locally for this reason, cracks are likely to occur particularly in the thin opposing part (4m'), causing concrete pieces to peel and fall off, causing the inductor coil ■ and The laminated core (1) will be exposed.

Therefore, in particular, induction coil devices placed on the bottom or side surfaces of the object to be heated (6) are not affected so much, but in those placed on the top surface of the object to be heated (6), the inductor coil ( 3) and the laminated iron core (ri) will directly receive the high-temperature radiant heat of the heated object (6), and this inductor coil (
3) and the insulation layer on the outer surface of the laminated iron core (凰) often suffered dielectric breakdown in a relatively short period of time due to the heat.

This invention was made with attention to this point, and a net-like body made of a heat-resistant and non-magnetic material is buried in a thin part of heat-resistant concrete in which an inductor coil and a laminated core are dug, facing the object to be heated. An object of the present invention is to provide an induction heating device which prevents concrete pieces from peeling off.

That is, FIG. 2 (A) CB) is a front sectional view and a side sectional view showing one embodiment of the present invention, and the same reference numerals as in the conventional one described above (FIG. 1) refer to the same constituent members. The explanation will be omitted.

(2) has the laminated core (1) and inductor coil I in place!
I) and the heated object (4) of heat-resistant concrete (4)
6) is a net-like body made of heat-resistant and non-magnetic material buried in the thin facing part (4a) of the heat-resistant concrete 14). This was installed to prevent the concrete pieces from peeling off and falling off even if the concrete were to enter. Incidentally, as the net-like body (6), for example, a commercially available stainless steel fiber such as "deceptive fiber" may be used.

Therefore, according to the present invention, the temperature difference becomes large locally, and the thin opposing portion (46) K of the heat-resistant concrete (4)
Even if cracking occurs, the concrete pieces will not peel off and fall off due to the presence of the mesh (8), so it will not be possible to expose the inductor coil or laminated core (1) like in the past. Therefore, the inductor coil and the laminated iron core receive high-temperature radiant heat from the object to be heated (6) directly and have an excellent effect of preventing dielectric breakdown of these insulating layers in a short period of time. It is.

[Brief explanation of the drawing]

Fig. 1 (4) and ⑤) are a front sectional view and a side sectional view showing a conventional induction heating device, and Fig. 2 (4) and ⑤) are a front sectional view and a side sectional view showing an embodiment of the present invention. It is. In the drawing, (1) is a laminated core, (1) is a water-cooled steel plate, (6)
is an inductor coil, (4) is a heat-resistant core/crystalline), (4
m) is a thin opposing part, (6) is an object to be heated, and (6) is a net-like body. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Shin Kuzuno - Eagle 1

Claims (1)

[Scope of Claims] (1) An induction heating device characterized in that a mesh body is buried in a thin part of heat-resistant concrete facing an object to be heated, in which a laminated iron core and an inductor coil are buried in predetermined positions. (The induction heating device according to claim 1, characterized in that a wire mesh made of a heat-resistant and non-magnetic material is used as the wire mesh. (2) The thickness of the thin facing portion is approximately 10%. (4) The induction heating device according to claim 1, characterized in that (4) stainless steel fiber such as "NA8 fiber" is used as the mesh body.
The induction heating device described in