JP2983710B2 - Electromagnetic pump duct - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic pump used for transferring molten metal to a casting machine, for example.
In particular, it relates to the structure of the duct.

[0002]

2. Description of the Related Art A conventional duct for an electromagnetic pump of this type has, for example, a configuration as shown in FIGS. 4 (a) and 4 (b). That is, the molten metal 105 as the conductive fluid
Has a cylindrical duct main body 100 for transporting the main body, an annular induction coil 101 arranged so as to surround the duct main body 100, and a core 102 arranged at a substantially central position of the duct main body 100. ing.

[0003] The core 102 is housed in a core protection tube 103 and inserted into the duct body 100 so as not to come into direct contact with the molten metal 105, and an annular molten metal passage is provided between the core protection tube 103 and the duct body 100. 104 are formed. The core protection tube 103 is a cylindrical member having a bottom and an open end thereof is closed by a plug 106 having a T-shaped cross section, and the duct body 100 is formed through a flange 107 of the plug 106.
And the core protection tube 103 are assembled concentrically. An outlet 108 through which the molten metal 105 flows out is provided in a flange 107 of the plug 106.

This electromagnetic pump forms a traveling magnetic field that travels in the transfer direction between the induction coil 101 and the core 102, and the traveling magnetic field causes the molten metal 105 in the molten metal passage 104 to flow.
An induced current is generated in the molten metal 105, and a thrust in a traveling direction is generated in the molten metal 105 by an interaction between the traveling magnetic field and the induced current to transport the molten metal 105.

[0005] Duct body 10 in contact with molten metal 105
The materials of the core 0, the core 102, and the core protection tube 103 are selected according to the type of the molten metal 105. In the case of the molten aluminum, ceramics are used. In addition, non-magnetic steel materials have been used for Mg and Zn melts.

Thus, the duct body 10 can be used for a long time.
Since the oxide gradually accumulates in the molten metal passage 104, the duct main body 100 and the core protection tube 103 are disassembled and the internal molten metal passage 104 is cleaned.

[0007]

However, in the case of the above-mentioned prior art, the cleaning operation of the inside of the duct body 100 is performed at a high temperature equal to or higher than the solidification temperature of the molten metal 105 so that the molten metal 105 is not solidified. Since it had to be done, it had to be done in a few minutes, and the workability was very poor.

[0008] In addition, when the temperature drops below the solidification temperature, reheating must be performed again.

Further, in order to dispose the core 102 inside the duct main body 100, three parts of the duct main body 100, the core protection tube 103 and the plug 106 are required, and the structure is complicated and expensive.

[0010] In particular, these parts for aluminum-based molten metal use ceramics and are assembled by machining, so that they are extremely expensive as compared with those for molten Zn and Mg which can use metal materials. Met.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to make it possible to provide a core outside a duct main body, thereby facilitating cleaning work inside the duct main body. Another object of the present invention is to achieve a low cost by simplifying the structure by eliminating the core protection tube and the plug body.

[0012]

In order to achieve the above object, according to the present invention, a core is provided at a substantially central position of a duct main body constituting a flow path for transferring a conductive fluid. In the duct of the electromagnetic pump, a concave portion is provided on the outer periphery of the duct main body to form a U-shaped cross-sectional flow path surrounding the concave portion inside the duct main body, and the core is housed in the concave portion to substantially cover the duct main body. It is characterized by being located at the center position.

[0013]

In the duct of the electromagnetic pump having the above-described structure, a concave portion for accommodating the core is provided on the outer periphery of the duct main body, so that the core is arranged on the outer peripheral side of the duct main body, and is disposed substantially at the center position of the duct main body. It is possible to do.

Therefore, the cross section U for transporting the conductive fluid
The U-shaped flow path is constituted only by the duct body, and it is not necessary to disassemble other components such as the core when cleaning the inside of the duct body.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. 1 to 3 showing a duct of an electromagnetic pump according to an embodiment of the present invention, reference numeral 1 denotes an entire configuration of the electromagnetic pump, and a duct main body for transferring a molten metal 2 as a conductive fluid. 3, an induction coil 4, a stator 5 on which the induction coil 4 is mounted, and a core 6 arranged at the center of the induction coil 4.

The duct main body 3 is a cylindrical member made of ceramics, and a concave portion 7 for accommodating the core 6 is provided on the outer periphery. Inside the duct body 3, a U-shaped cross section 8 is formed so as to surround the recess 7. The core 6 is a rod-shaped member having a circular cross section, and is disposed so that the central axis thereof is coaxially overlapped with the central axis of the duct body 3.
Is formed into a semi-circular cross-section following the cross-sectional shape of the core 6.

Therefore, by accommodating the core 6 in the recess 7, the core 6 is located substantially at the center of the duct body 3. The length of the recess 7 is substantially equal to the length of the core 6, and both ends in the axial direction of the duct main body 3 are formed in an annular cross section. Buffer members 16 are interposed between both end surfaces of the core 6 and both end surfaces of the concave portion 7.

The material of the duct body 3 is appropriately selected depending on the type of the molten metal flowing in the inside. In the case of Al, silicon nitride, aluminum titanate and the like are preferable.
In the case of Mg or Zn, it is effective to use a non-magnetic steel or the like.

The concave portion 7 of the duct body 3 is filled with a heat insulating material 9 such as a ceramic fiber so as to hide the core 6 in a state in which the core 6 is accommodated. It is formed in an arc surface so as to have the same circumference.

The heater 11 is wound around the outer periphery of the duct body 3 accommodating and holding the core 6 through the thin cylindrical stainless steel heater holder 10. The heater 11 is wound spirally over the entire length of the duct body 3, and the heat of the heater 11 is uniformly transmitted to the duct body 3 by interposing the heater holder 10.

Further, the heater 11 is embedded in a heat insulating material 12 such as a ceramic fiber formed into a thin cylindrical shape, and its outer periphery is covered with a heat insulating sheet 13 such as a ceramic sheet.

The outer periphery of the heat retaining sheet 13 is covered with a metal tube 14, and a stator 5 around which the induction coil 4 is wound is mounted on the outer periphery of the metal tube 14.

The stator 5 has the same length as the core 6,
Are arranged at the same position in the axial direction, and are provided in plural numbers in the circumferential direction. The annular induction coil 4 is mounted in an annular groove 15 provided on the inner peripheral surface of the plurality of stators 5. The induction coils 4 are arranged at predetermined intervals in the axial direction.

In the electromagnetic pump having the above configuration, a traveling magnetic field is formed between the core 6 and the induction coil 4 housed in the recess 7 on the outer periphery of the duct body 3, and the traveling magnetic field forms a U-shaped cross section surrounding the recess 7. An induced current flows through the molten metal 2 in the path 8, and an interaction between the induced current and the traveling magnetic field induced by the induction coil 4 generates a thrust in the molten metal 2 in the traveling direction. The molten metal 2 is transferred by this electromagnetic force, flows in from one end of the duct main body 3, passes through the central U-shaped flow path 8 in the center, and flows out from the other end.

Here, the flow path resistance when passing through the inside of the duct body 3 depends on the cross-sectional area of the U-shaped cross-section flow path 8, and this cross-sectional area is the same as that of the conventional outlet shown in FIG. 108, and the flow path resistance is almost the same as that of the related art.

By providing a recess 7 for accommodating the core 6 on the outer periphery of the duct body 3, the core 6 is
It is possible to dispose it on the outer peripheral side and at substantially the center of the duct body 3.

Therefore, the cross section U for transporting the molten metal 2
The U-shaped flow path 8 is constituted only by the duct body 3, so that it is not necessary to disassemble other constituent members such as the core 6 when cleaning the inside of the duct body 3, and the maintenance property is extremely improved.

Although the present embodiment has been described by taking a molten metal as an example of the conductive fluid, it is not limited to a molten metal.

The duct of the electromagnetic pump of the present invention can be applied to various types of electromagnetic pumps, such as a direct current type and an induction type. In short, the core is disposed substantially at the center of the duct body.
The present invention can be widely applied to an electromagnetic pump in which a flow path surrounding the periphery is formed.

[0030]

As described above, the present invention has the above-described structure and operation, and the cleaning of the flow path of the conductive fluid in the duct body has become extremely easy.

Further, the conventional core protection tube becomes unnecessary,
The cost can be reduced accordingly.

[Brief description of the drawings]

1A and 1B show an electromagnetic pump according to an embodiment of the present invention. FIG. 1A is a longitudinal sectional view, and FIG. 1B is a sectional view taken along line BB of FIG. 1A. (C) is a side view of the duct of (a).

FIG. 2 is a partially cutaway perspective view of the electromagnetic pump of FIG.

FIG. 3 is an exploded perspective view showing a part of a duct main body of the electromagnetic pump of FIG. 2 taken out and partially cut away.

FIG. 4 (a) is a sectional view showing a schematic configuration of a conventional electromagnetic pump, and FIG. 4 (b) is a right side view of a duct portion in FIG. 4 (a).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic pump 2 Molten metal (conductive fluid) 3 Duct main body 4 Induction coil 5 Stator 6 Core 7 Concave part 8 U-shaped cross section 9 Heat insulator 10 Heater holder 11 Heater

Claims (1)

(57) [Claims] 1. A duct of an electromagnetic pump having a core disposed substantially at a center position of a duct main body constituting a flow path for transferring a conductive fluid, wherein a concave portion is provided on an outer periphery of the duct main body and the inside of the duct main body is provided. A duct having a U-shaped cross section so as to surround the concave portion, and the core is housed in the concave portion and is located at a substantially central position of the duct main body.