JP2002098089A - Method and device for keeping balance of impeller in pump operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for keeping the balance of an impeller in pump operation diminishing hydraulic force, which is the factor of deflection, to keep the balance of the impeller without additionally providing an auxiliary blade and a counterweight. SOLUTION: As the method, magnetic force is generated between the opposed peripheral surfaces of the fixed side and rotating side in a pump casing, and the deflection of the impeller caused by hydraulic force during rotation is diminished by the magnetic force to keep dynamic balance in liquid. As the device, magnets 6, 7 are mounted to the opposed peripheral surfaces of the fixed side and rotating side in the pump casing 1 so that the deflection of the impeller 3 caused by the hydraulic force during rotation is diminished by the magnetic force of the magnets 6, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for maintaining the balance of an impeller, particularly a single-blade impeller or a bladeless impeller, during operation of a pump.

[0002]

2. Description of the Related Art As a countermeasure for maintaining the balance of an impeller during pump operation, a technical idea is to provide an auxiliary blade on the back surface of a shroud so as to maintain a hydraulic balance by the flow action of the auxiliary blade. Is known. However, the auxiliary blade does not produce the above-mentioned effect unless the blade width is made considerably large.Moreover, the auxiliary blade itself does not help the pumping action but rather significantly lowers the pump efficiency. It is not preferable to increase the size of the pump by the presence of the auxiliary blades.

[0003] As a measure for maintaining the balance of the impeller without using the above-mentioned auxiliary blades, it is widely practiced to provide a balance weight that balances the fluid force during rotation on the back surface of the shroud. However, when the impeller rotates, not only weight balance but also factors such as moment of inertia are added, so it is difficult to set the mounting position and weight of the balance weight. In addition, since the hydraulic imbalance force acting on the impeller has a different load value depending on the operating point of the pump, when installing the balance weight, determine the operating point of the pump in advance and determine the mounting position and weight. Will do. In other words, the balance maintaining function only works effectively at a specific operating point, and if the flow rate is smaller or larger than that, this additional load causes a negative effect that the shaft runout is a factor. It is.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a blade during pump operation that can reduce the fluid force that causes shaft runout and maintain the balance of the impeller without providing an auxiliary blade or a balance weight. It is an object of the present invention to provide a method and apparatus for maintaining the balance of a vehicle.

[0005]

According to the method for maintaining the balance of an impeller during operation of a pump according to the present invention, a magnetic force is generated between opposed peripheral surfaces on a fixed side and a rotating side in a pump casing, and the impeller is caused by fluid force during rotation. The shaft vibration of the vehicle is reduced by the magnetic force to maintain the dynamic balance in the liquid. Further, in the impeller balance maintaining device during the operation of the pump according to the present invention, a magnet is attached to the peripheral surface of the pump casing opposite to the fixed side and the rotating side so as to generate a suction force or a repulsive force, The shaft runout of the impeller due to the fluid force is reduced by the attraction or repulsion of the magnet.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The centrifugal pump using a single-blade impeller will be described below with reference to FIGS.

1 and 2, reference numeral 1 denotes a pump casing, 2 denotes a partition plate constituting the upper wall of the pump casing 1, 3 denotes an impeller housed in the pump casing 1, 4
Denotes a blade, and 5 denotes a shroud. Reference numeral 6 denotes a magnet mounted on the rotating side such as the outer peripheral surface of the shroud 5, and 7 denotes a magnet mounted on the fixed side in the pump casing 1 such as a lower portion of the peripheral wall of the partition plate 2 so as to face the magnet 6 on a different polarity. However, the magnet is not necessarily required to be a magnet as long as an attractive force acts between the magnet 6 and the magnet 6, and may be a simple magnetic body. It will be used as it is. The mounting position on the rotating side of the magnet 6 is set at a position where the fluid force acting when the impeller 3 rotates can be reduced by the attraction force of the magnet 6. 3 and 4, reference numeral 9 denotes a magnet mounted on the rotating side such as the outer peripheral surface of the shroud 5, and 10 denotes a magnet inside the pump casing 1 such as a lower portion of a peripheral wall of the partition plate 2 so as to face the magnet 9 at the same polar surface. The mounting position on the rotating side of the magnet 9 which is a magnet mounted on the fixed side and faces the magnet 10 can reduce the fluid force acting when the impeller 3 rotates by the repulsive force between the magnets 9 and 10. Set to position.

The number and arrangement of the above-mentioned magnets need not be as shown in the drawings of the embodiments, but the point is that an attractive force or a repulsive force acts in a direction to reduce the fluid force during rotation. I just need to. When the impeller rotates, a lateral pressure is applied to the pump shaft by the fluid force, but the above-mentioned side pressure is reduced by a magnetic force generated between the fixed side in the pump casing and the opposing peripheral surface on the rotating side, and the dynamic balance in the liquid is maintained. Will be done.

[0009]

According to the present invention, the balance of the impeller is reduced by reducing the fluid force which causes the shaft run-out irrespective of the operating point by arranging the magnet without providing the auxiliary blade or the balance weight. There is an advantage that can be maintained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part of a centrifugal pump equipped with the device of the present invention, showing an example in which a magnet is mounted on a peripheral surface of a pump casing facing a fixed side and a rotating side so as to generate an attractive force. .

FIG. 2 is a cross-sectional view taken along line XX of FIG.

FIG. 3 is a vertical sectional side view of a main part of a centrifugal pump provided with the device of the present invention, showing an example in which a magnet is attached to a peripheral surface of a pump casing facing a fixed side and a rotating side so as to generate a repulsive force. .

FIG. 4 is a transverse sectional view taken along line YY of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pump casing 3 Impeller 6 Magnet 7 Magnet 9 Magnet 10 Magnet

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H022 AA01 BA04 CA50 DA00 3H033 AA01 BB01 BB06 CC01 DD29 EE10

Claims (2)

[Claims] 1. A magnetic force is generated between opposed peripheral surfaces of a fixed side and a rotating side in a pump casing, and shaft runout of an impeller caused by fluid force at the time of rotation is reduced by the magnetic force to cause dynamics in liquid. A method for maintaining the balance of an impeller during operation of a pump, characterized in that the balance of the impeller is maintained. 2. A magnet is mounted on a peripheral surface of a fixed side and a rotating side in a pump casing so as to generate a suction force or a repulsive force, and shaft runout of an impeller caused by fluid force during rotation is reduced by the magnet. A balance maintaining device for an impeller during operation of a pump, wherein the device is configured to be reduced by suction force or repulsion force of the impeller.