JPS5824397Y2 - Mitsupugata Yudou Kanetsouchi - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a sealed induction heating device that heats the induction heating furnace by filling it with atmospheric gas such as nitrogen.

When heating a material such as steel in an induction heating furnace, when the material being heated comes into contact with the outside air, oxidation and decarburization occur on the surface of the material.

For this reason, a method has been adopted in which the inside of the furnace is sealed and shut off from the outside air, and atmospheric gas is sealed inside the furnace to heat the furnace.

However, there is a structure in which the material to be heated is placed on a support mechanism provided at the end of a drive shaft that drives in the vertical direction, and the material is carried into the induction heating furnace (hereinafter referred to as the furnace) from the ceiling or bottom of the furnace. After the material to be heated is brought in, it is necessary to seal the drive shaft insertion opening on the bottom of the furnace to prevent outside air from entering.

One possible method is to use a cylinder as the insertion port for the drive shaft and drive the drive shaft inside the cylinder, but this method requires very high dimensional accuracy between the inside of the cylinder and the outside of the drive shaft. It has the disadvantage of being expensive.

This idea was made in view of the above points, and by providing an enclosing member that moves together with the support base, and configuring this enclosing member to come into contact with the enclosing member at the bottom of the furnace to seal the furnace, It is an object of the present invention to provide a sealed induction heating device that eliminates the above drawbacks.

An embodiment of this invention shown in the drawings will be described below.

That is, the support base 2 having the refractory heat insulating material 1 on the upper surface is used to carry the material to be heated 3 placed on the upper surface of the support table 2 from the bottom surface of the induction heating furnace 4, and the material to be heated 3 is placed in the correct position with respect to the heating coil 6. Rise to a position of relationship.

The induction heating furnace 4 includes an induction heating coil 6 and an induction heating coil 6.
It consists of a refractory heat insulating material 7 that is inside and protects it, an iron core 8 that converges leakage magnetic flux, and a cylindrical first enclosing member 10 attached to the lower surface of the lower ring 9.

The induction heating coil 6 has an upper ring 11 and a lower ring 9.
The ring is strongly suppressed by a tie rod (not shown) connecting both rings, thereby preventing electromagnetic vibration.

Both rings 9 and 11 are usually made of metal (may be hollow and water-cooled), and are insulated from the induction heating coil 6 by an electrical insulating material 12.

Reference numeral 17 denotes a drive shaft attached to the lower part of the support base 2, and a donut-shaped second enclosing member 10' is attached thereto.

Reference numeral 18 denotes a groove formed on the upper surface of the second enclosing member 10', which is arranged in an annular shape so as to face the lower part of the first enclosing member 10, and contains a liquid such as water that acts as a sealant. is fulfilled.

Reference numeral 20 denotes an opening provided in the first enclosing member 10 to serve as a gas discharge port, and this opening 20 is opened and closed by a side cover 22 driven by a cylinder 23.

21 is a gasket, 24 is a gas pipe serving as a gas supply port for feeding atmospheric gas into the induction heating furnace 4 from the gas cylinder 25, 26 is a pressure reducing valve, and 27 is a valve.

In this structure, when the support base 2 on which the material to be heated 3 inserted from the lower part of the induction heating furnace 4 is raised to a predetermined heating position, the first enclosing member 10 moves to the second enclosing member 10. The bottom of the induction heating furnace 4 is immersed in water 19 in the groove 18 provided at 10', and the bottom of the induction heating furnace 4 is sealed by both enclosure members 10 and 10'.

When the interior of the induction heating furnace 4 is sealed, atmospheric gas is introduced into the furnace 5 from the gas cylinder 25.

As this atmospheric gas, nitrogen gas, which is inert and relatively inexpensive, is desirable.

When atmospheric gas lighter than air is introduced into the furnace 5 through the gas pipe 24, the original air is pushed down,
At this time, the water flows out from the opening 20, which is still open.

When the atmospheric gas is completely filled to the bottom, the opening 20 is closed.

It is preferable to replace the gas before starting heating, but if there is not enough time due to heat cycles,
The surface of the object to be heated does not oxidize or decarburize, for example, 500
If the replacement is completed before reaching a relatively low temperature below .degree. C., heating may be started before the atmospheric gas is sufficiently replaced.

Thereafter, when the replacement is completed, the valve 27 is closed.

Further, the sealing member is not limited to water, and it goes without saying that a flexible material such as rubber or packing may be used for sealing.

As described above, in the sealed induction heating device of this invention, in order to carry the material to be heated, which is placed on the upper surface of the support, from the bottom of the induction heating furnace to a predetermined heating position in the induction heating furnace, the support is connected to the drive shaft. In the case where the support table is moved up and down in the vertical direction, when the support table moves up and down integrally with the support table and the material to be heated is carried to a predetermined heating position, the material is placed at the bottom of the induction heating furnace. A second enclosing member is provided that contacts the first enclosing member provided, and the structure is such that the inside of the induction heating furnace is sealed from the outside air by contact between the two enclosing members. An operation is performed to form a sealed structure along with the material loading operation, and when the heated material is transported to a predetermined heating position, the insertion opening of the drive shaft is automatically sealed, so that the heating material is transported and sealed. The structure can be formed in a simple single operation.

In particular, this type of equipment is quite large, so if the loading of the material to be heated and the formation of the sealed structure were carried out separately, the structure and equipment for this would be large-scale. The structure is simple and the work is very easy, and since there is no sliding part in the sealing part, the seal between the inside of the furnace and the outside air at the drive shaft part is highly reliable. This has practical effects such as the ability to obtain

The enclosing members 10 and 10' are formed by processing a plate and fixing it to the lower ring 9 or the drive shaft 17, but they may also be formed by processing a part of the lower ring 9 or the support base 2. Needless to say, the same effect can be achieved.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view showing a sealed induction heating device which is an embodiment of this invention. In the figure, 2 is a support stand, 3 is a material to be heated, 4 is an induction heating furnace, 1
0.10' is a surrounding member, 17 is a drive shaft, 18 is a groove part, 1
9 is a sealing material.

Claims (1)

[Scope of utility model registration request] An induction heating furnace into which the material to be heated is carried in from the bottom, a support stand on which the material to be heated is placed on the top surface and the material to be heated is carried into a predetermined heating position in the induction heating furnace, and this support stand is moved in the vertical direction. a first enclosing member provided at the lower part of the induction heating furnace, which is provided on the drive shaft and moves up and down integrally with the support stand as the support stand moves; A second enclosing member that comes into contact with the first enclosing member when the material is carried into a predetermined heating position and seals the induction heating furnace from the outside air; A sealed induction heating device comprising: a gas supply port for supplying an atmospheric gas lighter than air; and a gas discharge port provided in the first enclosure member and capable of being opened and closed at predetermined times.