JPH071758Y2 - Crucible induction furnace - Google Patents

Description

[Detailed Description of the Invention] [Industrial application] The present invention relates to an iron core mounting structure for a crucible induction furnace.

[Conventional technology]

As shown in FIG. 3, this type of induction furnace supplies high-frequency power to the heating coil 2 surrounding the crucible 1 to generate a magnetic flux φ, and the magnetic flux φ causes an induction current to the metal in the crucible 1. It is generated and the metal is melted by the heat generated by the juule. The arrow attached to the coil 2 indicates the direction of current flow.

When the magnetic resistance of this magnetic circuit is R and the ampere-turn of the heating coil 2 is AT, the generated magnetic field strength H is proportional to AT / R. Therefore, if the magnetic resistance R is made small, the heating efficiency can be improved. .

For this reason, conventionally, there is an idea to arrange the iron core 6A outside the crucible 1 to reduce the magnetic resistance R of the magnetic circuit.
In order to provide a fixing position and fixing means for a plurality of iron cores 6A,
As a result, the structure becomes complicated, and the outer shape of the furnace becomes large. Therefore, especially in a small-sized induction furnace, the iron core 6A makes the size large, which is a troublesome problem.

The present invention has been made to solve the above problems, and an object thereof is to provide a crucible-type induction furnace in which the iron core can be arranged with a simple attachment structure without causing an increase in size. And

[Subject for solving problems]

In order to achieve the above object, the present invention has a structure in which a core is attached to at least one of left and right end faces of a stay provided for positioning and supporting a heating coil before forming a coil wall in a crucible induction furnace. Is.

[Action]

In the present invention, since iron cores are attached to the left and right end surfaces of the stay,
The outer diameter of the furnace can be the same as the conventional one, and the attachment can be performed with a plurality of bolts, so that no special attachment means is required.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a crucible, 3 is a coil wall (made of coil cement) in which a water-cooled heating coil 2 is embedded, 4
It is a sinter refractory material filled between the crucible 1 and the coil wall 3. The heating coil 2 has a plurality of support rods 2a extending outward in the radial direction in each turn 2A. 5 is a heating coil 2 before filling the coil cement to form the coil wall
Stays for positioning and holding the respective turns 2A, which are provided at predetermined intervals in the circumferential direction. This stay 5 has a plurality of holes 5a for passing the support rod 2a in series in the longitudinal direction, and a plurality of bolt holes (not shown) are formed on the end surface 5A facing the adjacent stay 5a. There is.
5b is a nut. Reference numeral 6 denotes an iron core formed by stacking silicon steel plates, which is fixed to at least one of the left and right end surfaces of the stay 5 with bolts 7.

In this configuration, most of the magnetic flux Φ generated by energizing the heating coil 2 flows through the iron core 6 and into the metal in the crucible 1, so that the resistance R of the magnetic circuit is small and the iron core 6 is not present. The heating efficiency is improved as compared with.

In this embodiment, the iron core 6 is arranged on the side surface of the stay 5,
Since the iron core 6 is interposed between the stays, the iron core 6 can be arranged without increasing the furnace outer diameter.

Further, since the iron core 6 is fixed by abutting on the end surface of the stay 5, the attaching means can be a simple means such as a bolt.

[Effect of device]

As described above, according to the present invention, since the stay is used to attach the iron cores, it is possible to provide a plurality of iron cores without increasing the size of the furnace and with a simple attachment means. In particular, there are some small-sized induction furnaces that have great practical effects.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIG. 2 is a horizontal sectional view of the above embodiment, and FIG. 3 is a view showing a basic structure of a crucible induction furnace. 1 ... crucible, 2 ... heating coil, 2a ... support rod, 3 ...
… Coil wall, 5 …… Stay, 6 …… Iron core.

Claims (1)

[Scope of utility model registration request] 1. A crucible shape having a crucible, a coil wall containing a heating coil and covering the crucible, and a plurality of stays provided vertically outside the coil wall for fixing support rods extending in the radial direction from the heating coil. In the induction furnace, a crucible-type induction furnace having iron cores serving as magnetic flux passages attached to at least one of the left and right end surfaces of each stay.