JPS63193487A - Induction heating electric furnace - 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 (Industrial Application Field) The present invention relates to an improvement of an induction heating electric furnace apparatus equipped with two furnace bodies that share a power supply facility and are operated in a switched manner.

(Prior art) Electric power is supplied from the power supply equipment to the furnace body coil wound around the furnace body to generate alternating magnetic flux, and this alternating magnetic flux is applied to the melted material (scrap) placed in the furnace body. An induction heating electric furnace device is in practical use that induces eddy current to heat and melt the melted material using Joule heat generated by its own resistance.

The general main equipment of this type of induction heating electric furnace equipment consists of a combination of a freely tiltable furnace body equipment and a power supply equipment that connects to the furnace body coil wound around the furnace body and supplies electric power. .

By the way, the above-mentioned power supply equipment is not only more expensive than the furnace body equipment, but also requires a huge amount of floor space for installation. It is often equipped with two units and operated by switching between them.

As mentioned above, when operating two furnace bodies by sharing the same power supply equipment, considering the power input from the power supply equipment to the furnace body, the power usage for holding and heating the molten metal after melting the melting material is It takes only a few minutes to melt and heat the material.

Therefore, in a power supply facility equipped only with a melting heating power source that can supply the power necessary for melting and heating,
The utilization rate of power supply equipment is the highest (nearly 100%) during melting and heating.
Even if it were, the power supply would be reduced during holding and heating of the molten metal, resulting in an extremely low utilization rate.In the end, the average utilization rate of the power supply equipment would be lowered due to the repetition of melting heating and holding heating.

In order to solve the above-mentioned drawbacks, the power supply equipment is equipped with a power supply for melting and heating and a power supply for holding and heating, and the furnace body coil of one furnace body is supplied with power from the power supply for melting and heating to melt the melting material. At the same time, there is a device in practical use that is configured to perform holding and heating by supplying power from a holding and heating power source to the furnace body coil of the other furnace body.

FIG. 3 is an explanatory diagram of the operation of this basic induction heating electric furnace apparatus equipped with two conventional furnace bodies.

The two furnace bodies 2 and 3 share the power supply equipment 1.

The power supply equipment 1 includes a power supply 1a for melting and heating and a power supply 1b for holding and heating.
This melting heating power source 1a and the holding heating power source 1
b is electrically connected to the furnace body coils wound around both furnace bodies 2 and 3, respectively, so that electric power required for melting heating and electric power required for holding heating can be switched and supplied.

In the operation of the above device, for example, the furnace body coil of one furnace body 2 is connected to the melted oil thermoelectric power source l1lJX1 of the power supply equipment l.
When the melting material is being melted and heated by connecting to the furnace body 3, the furnace body coil of the other furnace body 3 is connected to the holding and heating power supply 1b to hold and heat the molten metal and take out the molten metal, or to prepare the material to be melted next time. It performs heating.

(Problems to be Solved by the Invention) As described above, in an apparatus that combines power supply equipment having a melting heating power source and a holding heating power source for two furnace bodies,
While melting and heating is performed in the seven furnace bodies, holding and heating is performed in the other furnace body, and this can be operated repeatedly alternately.
Although the utilization rate of power supply equipment is high, it requires a dedicated power supply for holding and heating separately from the power supply for melting and heating.
As power supply equipment becomes larger and larger, the floor space it occupies increases, and the entire device becomes expensive in terms of cost.

This invention was made in view of the above points, and the power supply equipment does not have a dedicated power supply for holding and heating as a power supply equipment, but uses a part of the electric power from the power supply for melting and heating for holding and heating. The purpose of the present invention is to provide an inexpensive device that can reduce the size of the device, increase its utilization rate, improve the productivity of melting materials, and reduce the floor area of the equipment.

(Technical Means for Solving the Problems) The gist of this invention for solving the above objects is an induction heating electric furnace equipped with two furnace bodies that share power supply equipment and are operated in a switched manner. In this method, intermediate taps are provided in the furnace coils of both furnace bodies, and power is supplied to the furnace coil of one furnace body through the intermediate tap, so that holding heating is performed simultaneously with melting heating in the other furnace body. An induction heating furnace apparatus is characterized by the following configurations.

(Function) According to the present invention configured as described above, in two furnace bodies that share power supply equipment, one furnace coil can be switched to a coil by simultaneously operating the changeover switch attached to both furnace body coils. By energizing the entire body, the heat necessary for melting and heating the molten material introduced into the furnace body is generated, and by energizing a part of the other furnace body coil through its intermediate tap, the molten metal in the furnace is held and heated. Alternatively, it generates the heat necessary for preheating the next melting material introduced into the furnace body.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an electric circuit diagram of the apparatus of the present invention, and FIG. 2 is an operational diagram.

Two furnace bodies 5 that share the power supply equipment 4 and are operated by switching,
6 is the same as a known device of this kind.

The power supply equipment 4 in this invention has only a power supply for melting and heating.

Each furnace body coil 7 is wound around the two furnace bodies 5 and 6.
8 is provided with a plurality of intermediate taps 7c, 8c.

One end 7a, 8a of each furnace body coil 7.8 of both furnace bodies 5, 6 is connected to the power supply stage M4 by a power supply cable 9, and the other end 7b, 8b of each furnace body coil 7.8 is connected to the power supply stage M4 by a power supply cable 9. The coil 7.8 is connected in series through a changeover switch 10.11 attached to the coil 7.8, and this changeover switch 10.
．． 11 is the intermediate tap 7c of each furnace body coil 7.8
, 8c can be switched and connected.

In the above configuration, both changeover switches 10° 11 are operated at the same time, and by operating these changeover switches 10°11, for example, as shown in FIG. In the connected state, the other changeover switch 11 is selectively connected to any one of the plurality of intermediate taps 8C of the furnace body coil 8.

Under this condition, the power supplied from the power supply equipment 4 is proportional to the number of turns of the coils 7 and 8 in both furnace bodies, and while the furnace body 5 generates the heat necessary for melting and heating, the furnace body 6 generates the heat necessary for melting and heating. The heat necessary for holding and heating the molten metal or the heat for preheating the next melting material brush 4 introduced into the furnace body is generated.

(Effect) As described above, in this invention, by operating a changeover switch, a part of the furnace coil of one furnace body is connected in series with the furnace body coil of the other body, and the number of turns of each furnace body coil is adjusted. By utilizing the heat generated accordingly for melting heating and holding heating, the following effects can be achieved.

(1) Molten metal is obtained alternately and continuously from two furnace bodies,
The productivity of melting the molten material is high, and a flexible injection schedule for the molten metal can be established.

(2) Continuous heating of the molten metal reduces temperature changes, making it easy to adjust the chemical action or injection temperature of the molten metal.

(3) Average utilization rate of power supply equipment is always the highest (approximately 100%)
Therefore, there is less wasted power.

(4) The power supply equipment is only a power supply for melting heating.
Since a dedicated power source for holding and heating is not required, the floor area of the equipment can be reduced, and the equipment can be simplified and provided at low cost.

(5) It can be applied to existing equipment by partial improvement, and the operating efficiency of existing equipment can be improved.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of the apparatus of the present invention, FIG. 2 is an explanatory diagram of operation, and FIG. 3 is an explanatory diagram of operation of the conventional apparatus. 1″...Power supply equipment, 2, 3...Furnace body, 4...Power supply equipment, 5.6...Furnace body, 7,8...Furnace body coil, 9
...Power supply cable, 10.11...Selector switch.

Claims (1)

[Claims] In an induction heating electric furnace equipped with two furnace bodies that share power supply equipment and are switched and operated, an intermediate tap is provided in the furnace body coils of both furnace bodies, and the intermediate tap is provided in the furnace body coil of one furnace body. An induction heating furnace apparatus characterized in that it is configured to perform holding heating simultaneously with melting heating in the other furnace body by supplying power through the induction heating furnace.