JP4721498B2 - Method and apparatus for maintaining balance of single blade open impeller during pump operation - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to balanced holding method and apparatus for open impeller of single-vane that put the pump operation.
[0002]
[Prior art and its problems]
As a measure for maintaining the balance of the impeller during pump operation, a technical idea of providing auxiliary blades on the back surface of the shroud and maintaining hydraulic balance by the fluid action of the auxiliary blades is known. However, if the auxiliary blade is not made considerably wide, the above effect will not occur, and it does not assist the pumping action, but rather significantly reduces the pump efficiency. It is not preferable that the size of the pump is increased by the presence of such auxiliary blades.
[0003]
As a measure for maintaining the balance of the impeller without using the auxiliary blades described above, it is widely performed to provide a balance weight on the back surface of the shroud that balances the fluid force during rotation. However, when the impeller rotates, not only the weight balance but also factors such as moment of inertia are added, so it is difficult to set the balance weight mounting position and weight. In addition, since the hydraulic unbalance force acting on the impeller has a different load value depending on the operating point of the pump, the mounting position and weight are determined after the operating point of the pump is specified in advance. Will do. In other words, the balance maintaining function only functions effectively at a specific operating point, and if the flow rate is smaller or larger than this, a negative effect is produced in that this additional load causes a shaft runout. It is.
[0004]
OBJECT OF THE INVENTION
An object of the present invention, without attaching a support blade and the balance weight can be to diminish the fluid force causes the axial run-out to hold the balance of the open impeller single-vane, one of pump operation An object of the present invention is to provide a method and apparatus for maintaining the balance of an open impeller having a single blade .
[0005]
[Structure of the invention]
In the method for maintaining the balance of the single blade open impeller during pump operation according to the present invention, the dynamic unbalance of the outer peripheral surface of the shroud of the single blade open impeller housed in the pump casing is eliminated. A magnetic force is generated between the peripheral surface of one location and a plurality of locations over the entire circumference of the pump casing inner surface facing the outer peripheral surface of the shroud, and the shaft runout of the impeller caused by the fluid force during rotation is To maintain the dynamic balance in the liquid. Further, in the balance holding device for a single blade open impeller during pump operation according to the present invention, the dynamic unbalance of the outer peripheral surface of the shroud of the single blade open impeller housed in the pump casing is eliminated. Due to the fluid force at the time of rotation, a magnet is attached to generate a suction force or a repulsive force at one place in the direction and a plurality of places on the inner circumference of the pump casing that faces the outer surface of the shroud. The shaft runout of the impeller is configured to be reduced by the attractive force or repulsive force of the magnet.
[0006]
【Example】
Examples of FIGS. 1 to 4 in which a centrifugal pump using a single-blade open impeller is implemented will be described below.
[0007]
1 and 2, 1 is a pump casing, 2 is a partition plate constituting the upper wall of the pump casing 1, 3 is an open impeller of one blade accommodated in the pump casing 1, 4 is a blade plate, 5 Is a shroud. 6 is a magnet mounted at one location in the direction of destroying the dynamic imbalance of the outer peripheral surface of the shroud 5, and 7 is a pump casing 1 such as a lower portion of the peripheral wall of the partition plate 2 so as to face the magnet 6 at a different polarity surface. It is a magnet mounted at a plurality of positions on the fixed side over the entire circumference of the inside, but it does not necessarily need to be a magnet as long as an attractive force acts between the magnet 6 and may be a simple magnetic material. When 2 itself is made of a magnetic material, the lower part of the peripheral wall is used as it is. The mounting position on the rotation side of the magnet 6 is set to a position where the fluid force acting when the single impeller 3 rotates can be reduced by the attractive force of the magnet 6. 3 and 4, reference numeral 9 denotes a magnet mounted at one location in a direction that destroys the dynamic imbalance of the outer peripheral surface of the shroud 5, and reference numeral 10 denotes the partition plate 2 so as to face the magnet 9 at the same polar surfaces. The lower part of the peripheral wall is a magnet mounted at a plurality of positions on the fixed side over the entire circumference in the pump casing 1, and the mounting position on the rotation side of the magnet 9 facing the magnet 10 is an open impeller with one blade. 3 is set at a position where the fluid force acting at the time of rotation 3 can be reduced by the repulsive force between the magnets 9 and 10.
[0008]
The number and arrangement pattern of the magnets described above, need not be at passing Ride embodiment, short, attraction or repulsion in a direction to counteract the fluid force upon rotation is can I action. When the single impeller open impeller rotates, a side pressure is applied to the pump shaft by fluid force. The lateral pressure is reduced by the magnetic force generated between the opposing peripheral surfaces of one location and a plurality of locations over the entire circumference of the inner surface of the pump casing facing the shroud outer peripheral surface, and the dynamic balance in the liquid is maintained. become.
[0009]
【The invention's effect】
According to the present invention, the balance of the single impeller open impeller can be achieved by reducing the fluid force that causes the axial run-out regardless of the operating point by providing the auxiliary vanes and the balance weight, regardless of the operating point. There is an advantage that can be held.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional side view of a main part of a centrifugal pump provided with the device of the present invention, in which the dynamic unbalance of a shroud outer peripheral surface of a single blade open impeller housed in a pump casing is destroyed. An example is shown in which a magnet is mounted so as to generate an attractive force at one location and a plurality of locations facing the shroud outer circumferential surface across the entire circumference of the inner surface of the pump casing.
2 is a cross- sectional view taken along line XX in FIG. 1 to explain the situation of the shroud outer circumferential surface facing one location in the direction of eliminating dynamic imbalance; It is the cross-sectional view which showed only the counter magnet in it.
FIG. 3 is a longitudinal sectional side view of a main part of a centrifugal pump provided with the device of the present invention, in which the dynamic imbalance of the outer peripheral surface of the shroud of a single blade open impeller housed in the pump casing is destroyed. An example is shown in which a magnet is mounted to generate a repulsive force at one location and a plurality of locations across the entire circumference of the inner surface of the pump casing that faces the outer surface of the shroud.
4 is a cross- sectional view taken along line Y-Y in FIG. 3 to explain the situation of the shroud outer peripheral surface facing one location in the direction of destroying the dynamic imbalance. It is the cross-sectional view which showed only the counter magnet in it.

Claims (2)

One location in the direction of destroying the dynamic imbalance of the shroud outer peripheral surface of the single impeller open impeller housed in the pump casing, and a plurality of locations over the entire circumference of the pump casing inner surface facing the shroud outer peripheral surface The pump operation is characterized in that a magnetic force is generated between the opposed peripheral surfaces and the shaft runout of the impeller caused by the fluid force during rotation is reduced by the magnetic force to maintain a dynamic balance in the liquid. How to maintain the balance of an open impeller with one blade at a time. One location in the direction of destroying the dynamic imbalance of the shroud outer peripheral surface of the single impeller open impeller housed in the pump casing, and a plurality of locations over the entire circumference of the pump casing inner surface facing the shroud outer peripheral surface A magnet is attached to the peripheral surface opposite to the magnet so as to generate an attractive force or a repulsive force, and the shaft shake of the impeller caused by the fluid force during rotation is reduced by the attractive force or the repulsive force of the magnet. An apparatus for maintaining a balance of an open impeller having one blade during pump operation.

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