JP2766967B2 - Eddy current prevention device for pump suction tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eddy current prevention device capable of reliably preventing eddy currents when pumping water from a water absorption tank.

[0002]

2. Description of the Related Art When pumping water from a river or the like, as shown in FIGS. 5 and 6, a water absorption tank 1 communicating with a river or the like is formed, and a rotating end is formed inside the water absorption tank 1 at an end thereof. Feather 2
a pump 2 comprising a casing 2b rotatably provided with a, a pumping pipe 2c integrally connected to an upper end of the casing 2b, and a suction port 2d integrally formed at a lower end of the casing 2b, and operating the pump 2 By doing so, pumping water from the water absorption tank 1 is generally performed.

[0003] In the above configuration, the flowing water is stagnant between the terminal side wall 1a of the water absorption tank 1 and the pump 2 to easily generate a dead water area. It is known that a vortex 3 is generated on a free water surface FWL by causing a rotation motion by interaction with a water flow A flowing near the water flow A.

When the vortex 3 grows and air is sucked into the pump 2, noise and vibration are generated, and the performance of the pump 2 is reduced.

Therefore, conventionally, in order to solve the above-mentioned drawbacks,
As shown by phantom lines in FIGS. 5 and 6, the vortex preventing wall 4 whose lower end extends below the lowest water level LWL above the pump 2 in the water absorption tank 1 is located above the water absorption tank 1. From the skeleton 5 provided at the center. In FIG. 5,
HWWL is the highest water level.

[0006]

According to the above-mentioned conventional structure, a part of the flowing water passing under the vortex preventing wall 4 is absorbed by the water absorbing tank 1.
Flows between the terminal side wall 1a and the pump 2 to prevent the formation of a dead water area therebetween. However, flowing water in contact with the upstream side surface 4a of the vortex preventing wall 4 stagnates, and Water area is likely to occur, and free water surface F of this dead water area
A new problem arises in that the vortex 3 generated in W · L grows and air is sucked into the pump 2, causing the noise and vibration of the pump 2 and deteriorating the performance of the pump 2.

The present invention has been made in consideration of the above-described conventional problems, and has as its object to provide a vortex preventing device for a pump suction tank that can reliably prevent generation of a vortex caused by a dead water area.

[0008]

In order to achieve the above-mentioned object, the present invention provides a pump provided at a terminal side in a water absorption tank, and a lower end of the pump located upstream from the pump in the water absorption tank. The vortex prevention device for a pump water absorption tank, which has a vortex prevention wall extending vertically downward, wherein the upper end is located between the highest water level and the lowest water level, upstream of the vortex prevention wall in the water absorption tank. In addition, an auxiliary wall for preventing eddy current whose lower end is located below the lowest water level is disposed transversely at a predetermined facing distance from the eddy current preventing wall.

[0009]

According to the above construction, the eddy current prevention wall is provided on the upstream side of the pump, and the eddy current prevention auxiliary wall is provided on the further upstream side of the eddy current prevention wall. A portion of the flowing water flows over the auxiliary wall and flows down along the upstream side surface of the vortex preventing wall, and a part of the flowing water passes below the vortex preventing wall forms the pump and the terminal side wall of the water absorption tank. No dead water area is generated between the upstream side of the eddy current prevention wall and the pump and the terminal side wall of the water absorption tank. Therefore, the generation of a vortex caused by the dead water area is reliably prevented, and the pump can be efficiently operated to reliably pump water from the water suction tank.

[0010]

1 and 2 show an embodiment of the present invention, in which an upper end 6a has a maximum water level HWWL and a minimum water level HWL upstream of a swirl prevention wall 4 in a water absorption tank 1. FIG. Water level L ・ W ・ L
And its lower end 6b is at the lowest water level L
An auxiliary wall 6 for preventing eddy currents located below W · L is laid transversely at a predetermined opposing interval α from the eddy current preventing wall 4.

To explain the operation at the time of pumping, when the pump 2 is operated, a part of the flowing water sucked by the pump 2 passes over the auxiliary wall 6 and the upstream side surface 4a of the vortex preventing wall 4. , The dead water area due to the stagnation of the flowing water does not occur on the upstream side of the eddy current prevention wall 4, and the generation of the vortex caused by the dead water area can be prevented.

Further, since a part of the flowing water that has passed under the swirl prevention wall 4 flows between the pump 2 and the terminal side wall 1a of the water absorption tank 1, a dead water area does not occur even during this time.
The generation of a vortex can be prevented.

Therefore, the pump 2 does not draw in the air due to the swirling flow and does not cause vibration or noise, and the pump 2 can be operated efficiently to pump water reliably.

In the above configuration, the upper end 6a of the auxiliary wall 6
Is preferably located below an intermediate water level MWL set midway between the highest water level HWL and the lowest water level LWL. Accordingly, when the water level is normal, the upper end 6a of the auxiliary wall 6 is located below the water surface, and the generation of the vortex can be reliably prevented.

As a result of the experiment, when the distance α between the eddy current preventing wall 4 and the auxiliary wall 6 is set to about 1.8 times the diameter D of the suction port 2d of the pump 2, the effect of preventing the eddy current is most effective. It was confirmed that it appeared remarkably.

In the above embodiment, the auxiliary wall 6 having the same length as the width of the water absorption tank 1 is used, and both ends of the auxiliary wall 6 are fixed to the side walls 1b, 1b of the water absorption tank 1. , FIG.
As shown in FIG. 5, an auxiliary wall 6 composed of a pair of auxiliary wall members 6A, 6A is used, and the base ends of the auxiliary wall members 6A, 6A are fixed to the side walls 1b, 1b of the water absorbing tank 1 and the distal end thereof. May be extended to near the center of the water absorption tank 1,
Further, an auxiliary wall 6 whose length is slightly shorter than the water absorption tank 1 may be used, and the auxiliary wall 6 may be integrally connected to the eddy current prevention wall 4 via a connecting rod 7.

[0017]

According to the present invention, the eddy current prevention wall is provided upstream of the pump and the eddy current prevention auxiliary wall is provided further upstream of the eddy current prevention wall. A vortex can be prevented from being generated between the pump and the upstream side of the pump and the terminal side wall of the water absorption tank. Therefore, the pump does not suck the eddy current to generate vibration and noise, and the pump can be operated efficiently to reliably pump water from the water suction tank.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a vortex preventing device for a pump water absorption tank according to an embodiment of the present invention.

FIG. 2 is a horizontal sectional view of the same.

FIG. 3 is a horizontal sectional view showing another embodiment of the present invention.

FIG. 4 is a horizontal sectional view showing still another embodiment of the present invention.

FIG. 5 is a longitudinal sectional view showing a conventional example.

FIG. 6 is a horizontal sectional view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water absorption tank 2 Pump 3 Eddy current 4 Eddy current prevention wall 6 Eddy current prevention auxiliary wall 6a Upper end of eddy current prevention auxiliary wall 6b Lower end of eddy current prevention auxiliary wall H ・ W ・ L Highest water level L ・ W ・ L Lowest water level

Claims (1)

(57) [Claims] 1. A pump suction device comprising: a pump provided at a terminal side in a water absorption tank; and a vortex prevention wall having a lower end extending downward below a minimum water level at an upstream side of the pump in the water absorption tank. In the eddy current prevention device for a water tank, the eddy current whose upper end is located between the highest water level and the lowest water level and whose lower end is located below the lowest water level is located upstream of the eddy current prevention wall in the water absorption tank. An eddy current prevention device for a pump water absorption tank, wherein an auxiliary wall for prevention is disposed transversely at a predetermined distance from the eddy current prevention wall.