JPS5814702Y2 - electromagnetic pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic pump having an improved support structure for a duct through which a conductive fluid to be transported passes.

Recently, electromagnetic pumps have come into widespread use as a means of transporting liquid sodium, which is the coolant for fast breeder reactors.

At the same time, because electromagnetic pumps are easy to operate and maintain, and have excellent safety and reliability, the capacity of electromagnetic pumps is being increased further.

The principle of an electromagnetic pump is that by passing a current through a conductive fluid on which a magnetic field is acting, a body force is generated in the conductive fluid through the interaction of the magnetic field and the current, thereby performing a pumping action.

The structure of the electromagnetic pump is to create a moving magnetic field generator with a stator coil wound around a stator core like a linear motor, and to wrap a duct in which the conductive fluid to be transported passes between opposing sides of the generator with heat insulating material. The configuration is as follows:

In an electromagnetic pump, the internal pressure of the duct increases as the pressure of the fluid increases during pump operation.

In order to maintain the strength of the duct, the thickness of the duct within the stator is increased, or reinforcing materials are provided within the duct to partition the flow passages for reinforcement.

However, increasing the wall thickness of the duct to maintain its strength increases the current induced in the duct by the moving magnetic field.

This induced current does not contribute to the pumping action of the electromagnetic pump at all, but merely causes a decrease in pump efficiency.

In addition, providing a reinforcing material for the partition plate electrically reduces the induced current flowing in the conductive fluid to be transferred, leading to a decrease in pump discharge pressure and ultimately to a decrease in pump efficiency.

Both duct reinforcement measures reduced the efficiency of the electromagnetic pump.

An object of the present invention is to provide an electromagnetic pump in which a duct is reinforced with high efficiency and reliability without reducing pump efficiency.

Embodiments of the present invention shown in the drawings will be described below.

In FIG. 1, a pair of stator cores 1, 1 are arranged with a predetermined gap, and stator coils 2, 2 are placed between the cores 1, 1.
are respectively wound to constitute moving magnetic field generating devices 3, 3 such as linear motors.

As shown in the figure, this iron core 1.1 is fixed to stator frames 4, 4, and the stator frames 4, 4 are further connected together by connecting bodies 5, 5.

A duct 6 is inserted into the gap between the two stator cores 1, 1 to serve as a passage 9 for the conductive fluid to be transported.

When inserting and fixing this duct 6 into the gap between the stator cores 1 and 1, a spacer 7 having a height equal to the gap length between the core 1 and the duct 6 is inserted.

This spacer 7 is used to prevent the duct 6 from deforming due to the pressure of the conductive fluid, and is made of a sufficiently rigid material, and the number of spacers used and the spacing between the spacers 7 and 7 are determined to prevent deformation due to the internal pressure of the duct 6. It is up to you to decide.

Furthermore, a heat insulating material 8 is filled between the stator 1 and the duct 6 to cover the entire surface of the duct 6 in order to reduce heat dissipation from the duct 6 which is at a high temperature.

In the electromagnetic pump configured as described above, it is assumed that the conductive fluid flows through the passage 9 of the duct 6 from the surface of the paper to the back of the paper.

When alternating power is supplied to the stator coil 2, an induced current 10 circulates between the pole pitches in the conductive fluid as shown in FIG. 2A, and the moving magnetic field becomes like the magnetic flux φ in FIG. 2B.
Move in the direction of arrow Y.

Therefore, the conductive fluid in the duct 6 moves from the surface of the paper to the back of the paper in FIG. 1 and in the direction of arrow Y in FIG.

At this time, the internal pressure of the duct 6 increases, but the highly rigid spacer 7 effectively prevents the duct 6 from deforming.

Ideally, the spacer 7 is made of an insulating material, but it is also possible to use a conductive material such as stainless steel.

However, when the spacers 7 are made of a conductive material, the spacers 7 should be arranged parallel to the fluid flow direction Y as shown in FIG.
Circulating current can be prevented from occurring through the spacers 7 by arranging them at right angles to the columnar spacers 7 and by arranging the columnar spacers 7 at appropriate intervals as shown in FIG.

Furthermore, as shown in FIG. 6, circulating current can be eliminated by making the interval H between the members perpendicular to the fluid flow direction Y twice the pole pitch.

As described above, according to the present invention, the gap length is defined in the gap between the fixed core and the duct that serves as the conductive fluid passage, and a highly rigid spacer is inserted to prevent the duct from deforming. Reinforcing measures against deformation of the duct are taken, and as a result, the wall thickness of the duct can be reduced, and an electromagnetic pump with low loss and high operating efficiency can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the electromagnetic pump of the present invention, Figs. 2 A and B are distribution diagrams showing the circulating current generation state and the moving magnetic field generation state, and Figs. 3 to 6 are the ducts used in the present invention. FIG. 3 is a plan view showing different embodiments. 1... Stator core, 2... Stator coil, 3... Moving electric field generator, 6...
Duct, 7...Spacer, 8...Heat insulation material.

Claims (5)

[Scope of utility model registration request] (1) Generation of a moving magnetic field consisting of a duct through which the conductive fluid to be transported passes, a stator core placed opposite the duct to apply a moving magnetic field to the conductive fluid in the duct, and a stator coil wound around the stator core. A conductive fluid is provided with a required number of spacers made of a highly rigid metal material that maintains the gap length between the fixed iron core of the moving magnetic field generator and the duct and restrains deformation due to internal pressure of the duct. An electromagnetic pump characterized in that the spacers are arranged along the flow direction and a heat insulating material is filled between the spacers. (2) The electromagnetic pump according to claim 1, wherein the plurality of spacers arranged along the flow direction of the conductive fluid are arranged in parallel to the flow direction of the conductive fluid. . (3) The electromagnetic pump according to claim 1, wherein the plurality of spacers arranged along the flow direction of the conductive fluid are arranged at right angles to the flow direction of the conductive fluid. . (4) A utility model registration claim characterized in that the plurality of spacers arranged along the flow direction of the conductive fluid are columnar spacers, and these spacers are arranged between the stator core and the duct. The electromagnetic pump described in scope 1. (5) The spacer disposed along the flow direction of the conductive fluid is constituted by a combination of a member parallel to the flow direction of the conductive fluid and a member perpendicular to the flow direction of the conductive fluid. The electromagnetic pump described in item 1.