JP2001317496A - Pump suction passage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump suction passage capable of effectively restraining a swirl flow with a simple structure. SOLUTION: This pump suction passage is arranged in the upstream of a pump suction port 15, and is constituted so as to transfer to a closed waterway 30 from an opening waterway 20. Means 40 and 40 are arranged for preventing the swirl flow R from growing into an air sucking vortex by weakening strength of the swirl flow R for the turning flow R trend to be generated in the vicinity of a water surface of an inlet port 50 transferring to the closed waterway 30 from the opening waterway 20 of the suction passage. These means 40 and 40 are a swirl restraining member (actually, straightening guides) for weakening the strength of the swirl flow R by restraining turning itself of the generating swirl flow R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pump suction passage.

[0002]

2. Description of the Related Art In recent years, pump stations for drainage have increased in capacity due to the spread of urbanization. In large-diameter pumps, suction closed-type and suction semi-closed-type water intake channels have been often used in order to reduce the civil engineering capacity of the pump station.

FIG. 5 is a view showing a suction closed type pump water suction passage, wherein FIG. 5A is a schematic side sectional view and FIG.
Is a schematic plan view. As shown in the figure, the water suction passage is provided upstream of the suction port 85 of the pump P, and is configured to transition from an open water passage 90 having a water surface in contact with the atmosphere to a closed water passage 95 having no water surface in contact with the air. Have been.

Here, the closed channel 95 is a channel surrounded by a bottom surface 97, both side walls, and a ceiling surface 99 (99A, 99B) and through which water flows so as to fill the inside thereof.
A ceiling surface 99A formed so as to be obliquely inclined from a lower end of the drinking opening 110 of the vertical wall 101;
Ceiling surface 99B formed to extend horizontally from the rear end of
And is constituted by.

When the pump P is driven to rotate the impeller 81, water is sucked from the open channel 90 into the closed channel 95, pumped up by the pump P and drained to a predetermined place.

However, in the above-described conventional pump suction channel, as shown in FIG.
A swirling flow R is generated in the vicinity of both ends of the water surface at the upper part of 10. In the swirling flow R, the flow velocity of the water flowing in the vicinity of both ends thereof is lower than the flow velocity in the central part of the water flowing in the vicinity of the water surface of the open channel 90, and is generated by this velocity difference. When the swirling flow R is drawn into the downward flow flowing into the closed channel 95 from the drinking opening 110, a vortex is generated. And open channel 9
When the water level of 0 (suction water level) is low or when the inflow speed is high, the vortex grows into an air suction vortex that reaches the suction port 85 of the pump P, which causes noise and vibration of the pump P. There was a problem.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a pump suction passage having a simple structure and capable of effectively suppressing a swirling flow. Is to do.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a pump suction passage provided upstream of a pump suction port and configured to transition from an open water passage to a closed water passage. Measures are taken to prevent the swirl flow from growing into the air suction vortex by reducing the strength of the swirl flow for the swirl flow that is about to be generated near the water surface of the drinking mouth that transitions from the open channel to the closed channel of the road. It is characterized by having been provided.

Here, the means for preventing the swirl flow from growing into the air suction vortex by weakening the strength of the swirl flow suppresses the swirl of the generated swirl flow itself to reduce the swirl flow strength. It is preferable that the swirling flow suction suppressing member is provided below the generated swirling flow to suppress the downward growth of the swirling flow to weaken the strength of the swirling flow.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, as means for suppressing the swirling flow, means for preventing the swirling flow from growing into an air suction vortex by reducing the strength of the swirling flow is proposed. Hereinafter, this means will be described in detail using a specific embodiment.

[Means for Preventing a Swirl Flow from Growing into an Air Swirl by Decreasing the Strength of the Swirl Flow] FIG. 1 is a view showing a suction closed pump suction passage to which an embodiment of the present invention is applied. (A) is a schematic side sectional view, and (b) is a schematic plan view. As shown in the figure, the water suction passage is installed upstream of the suction port 15 of the pump P,
To the closed channel 30. The closed channel 30 includes a bottom surface 37, both side walls, and a ceiling surface 39 (39A, 39).
B) and the ceiling surface 39 is a vertical wall 41
The ceiling surface 39A is formed so as to be obliquely inclined from the lower drinking port 50, and the ceiling surface 39B is formed to extend horizontally from the rear end of the ceiling surface 39A.

The pump P includes an impeller 61 housed in a casing 63 formed by a frame, and a shaft 65 attached to the impeller 61 is connected to a reduction gear and a motor (not shown).

In this embodiment, the open channel 20
Plate-like rectification guide (rotation suppression) that rectifies the flow of water in the direction from the open channel 20 to the closed channel 30 at both sides in the width direction near the water surface above the drinking opening 50 that transitions from the opening to the closed channel 30. Members) 40, 40 are provided. That is, these rectifying guides 40, 40 are provided with swirling flows R, R shown in FIG.
Is provided in a portion where the occurrence of the

When the pump P is driven to rotate the impeller 61, the closed channel 3 is opened from the open channel 20 through the drinking port 50.
Water is sucked into the water, pumped up by the pump P, and discharged to a predetermined place.

At this time, a swirling flow R is generated in the vicinity of both ends of the water surface above the drinking opening 50 of the open channel 20, but the rectifying guides 40 obstruct the swirling and weaken the strength of the swirling flow R. . Since the swirling flow R is weakened, the swirling flow R does not grow into an air suction vortex even if the swirling flow R is drawn into the downward flow flowing into the closed channel 30 from the drinking opening 50. In addition, even when the water level (suction water level) of the open channel 20 is low or the water suction speed is high at this time, the swirling flow R grows into an air suction vortex reaching the suction port 15 of the pump P. I will not do it.

The rectifying guides 40, 40 may be members having various shapes other than a flat plate. The point is that a swirl suppressing member which suppresses the swirl itself of the generated swirl flow and weakens the strength of the swirl flow may be used.

FIG. 2 is a view showing a suction closed type pump suction passage to which another embodiment of the present invention is applied. FIG. 2 (a) is a schematic side sectional view, and FIG. 2 (b) is a schematic plan view. is there. In the figure, the same parts as those of the embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The present embodiment differs from the embodiment shown in FIG. 1 in that a bar member (a swirl flow suction suppressing member) 45 is provided instead of installing the rectifying guides 40,40. That is, the rod member 45 moves from the open channel 20 to the closed channel 30.
It is installed over the entire width of the waterway in the width direction below the upper surface of the water near the drinking mouth 50 that shifts to.

When the pump P is driven to suck water from the open channel 20 into the closed channel 30 through the drinking port 50, the swirling flow R is generated near the both ends of the water surface above the drinking port 50 of the open channel 20.
Is generated, and is drawn into the downward flow flowing into the closed channel 30 so as to become a vortex. However, since the rod member 45 is located at the root of the vortex, it hinders the downward growth of the vortex, and the swirling flow The strength of R is reduced. And since the swirling flow R is weakened, even if the water level (suction water level) of the open channel 20 is low or the inflow speed of water is high,
This swirling flow R does not grow into an air suction vortex that reaches the suction port 15 of the pump P.

In this embodiment, the rod 45
Is installed so as to cover the entire width of the water channel. However, the rod member 45 may be provided at least near both sides of the water channel where the swirling flow R occurs as shown in FIG. Although the rod member 45 is provided in these embodiments, the rod member 45 may be a plate-shaped member or a member having another shape. In short, any swirl flow suction suppressing member that is installed below the generated swirl flow to suppress the downward growth of the swirl flow and weaken the strength of the swirl flow may be used.

In each of the above embodiments, an example is shown in which the present invention is applied to a suction closed type water intake passage. However, the present invention can also be applied to a suction semi-closed type water intake passage. FIG.
FIG. 2 is a schematic side sectional view showing an example in which the pump water suction passage shown in FIG. 1 is applied to a suction semi-closed type water suction passage. In the figure, the part of the pump suction channel is exactly the same as that of FIG.
The only difference is that the pump P 'in which an impeller or the like is housed in a casing is inserted and installed in a hole 67 provided in a frame. It goes without saying that the function of the pump suction channel is the same as that of the embodiment shown in FIG.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims and the technical idea described in the specification and the drawings. Is possible. It should be noted that any shape or material not directly described in the specification and the drawings is within the scope of the technical idea of the present invention as long as the effects and effects of the present invention are exhibited.

[0023]

As described above in detail, according to the present invention, the structure can be simplified and the swirl flow can be effectively suppressed, even when the water level (suction water level) of the open channel is low. Even when the inflow speed is high, the swirling flow does not grow into an air suction vortex reaching the suction port of the pump, and has an excellent effect that the pump does not generate noise or vibration.

[Brief description of the drawings]

FIG. 1 is a view showing a suction closed type pump water suction passage to which an embodiment of the present invention is applied, wherein FIG. 1 (a) is a schematic side sectional view, and FIG. 1 (b) is a schematic plan view.

FIGS. 2A and 2B are diagrams showing a suction closed type pump water suction passage to which another embodiment of the present invention is applied, wherein FIG. 2A is a schematic side sectional view and FIG. 2B is a schematic plan view.

FIG. 3 is a schematic plan view showing a suction closed type pump water suction passage to which another embodiment of the present invention is applied.

FIG. 4 is a schematic side sectional view showing a suction semi-closed pump water suction passage to which the present invention is applied.

FIGS. 5A and 5B are diagrams showing a conventional suction closed type pump suction channel, wherein FIG. 5A is a schematic side sectional view and FIG. 5B is a schematic plan view.

[Explanation of symbols]

 P pump 15 suction port 20 open channel 30 closed channel 37 bottom surface 39 (39A, 39B) ceiling surface 40, 40 rectification guide (turn control member) 41 vertical wall 45 bar member (turn flow suction control member) 50 intake port 61 impeller 63 Casing 65 Shaft R swirling flow

Claims (2)

[Claims] 1. A pump suction passage installed upstream of a pump suction port and configured to shift from an open channel to a closed channel, in the vicinity of a water surface of a drinking port that shifts from an open channel to a closed channel of the suction channel. A pump suction passage provided with means for preventing the swirling flow from growing into an air suction vortex by reducing the strength of the swirling flow with respect to the swirling flow to be generated. 2. A swirl for reducing the strength of the swirl flow to prevent the swirl flow from growing into an air suction vortex by reducing the strength of the swirl flow. The swirling flow suction suppressing member, which is provided below the generated swirling flow and suppresses downward growth of the swirling flow to reduce the strength of the swirling flow. Item 7. The pump water intake according to Item 1.