JPH09256991A - Previous standby operating pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress vibration and noise by rapidly discharging remaining water in a pump when operation is switched into a pumping shutout operation, and to suppress consumption of energy by reducing the fuel consumption rate or the power consumption rate of a prime mover. SOLUTION: Four flap valves 12, 12 are installed on a cross shaped valve seat arranged on the lower end part of a pumping pipe 4, the flap valves 12, 12 is pushed up by water flow during a drain operation so as to open a valve, and the valve is closed by the self weight of the flap valves 12, 12 when water flow is stopped after pumping is shutout. A valve closing condition is held by attraction action of an electric stone 14, an opening/closing valve 17 is opened when the flap valves 12, 12 are closed, and remaining water in a pumping pipe 4 makes fall down through a water falling pipe 16A. The opening/ closing valve 17B is opened, and few remaining water which exists between the outlet of the impeller 2 and the flap valves 1, 12 makes fall down through the water falling pipe 16B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stand-by pump, and more particularly, to a stand-by pump for suppressing vibration, noise, power consumption, etc. during pumping cutoff operation.

[0002]

2. Description of the Related Art A pump shown in FIG. 5, for example, has been conventionally known as a pump performing a preparatory standby operation. In this preceding standby operation pump, an impeller 2 fixed to a main shaft 1 is rotatably housed in a casing 3, a pumping pipe 4 is connected to a discharge side of the casing 3, and a suction cover 5 is connected to a suction side of the casing 3. At the same time, the suction cover 5 is communicated with a steam / water switching system 6 including an atmosphere / open steam / water switching pipe 6B provided with a steam / water switching valve 6A. And the water level detection means 7
The water / water switching valve 6A is configured to be opened / closed by a signal output from the controller 8 based on the water level signal detected by the water intake well 10. Further, the main shaft 1 is watertightly and rotatably pierced through the discharge elbow 11 to extend to the outside and is connected to a prime mover (not shown).

An operation example of the preceding standby operation pump configured as described above will be described. When the water level of the water absorption well 10 rises. A-. Until the water level exceeds the pumping cutoff water level SWL and reaches the pumping start water level RWL, the air / water switching valve 6A is opened to perform in-air operation. A-. When the pumping start water level RWL is reached, the air / water switching valve 6A is closed, and the normal drainage operation (1
00% Q), and the normal drainage operation is performed at the water level equal to or higher than the pumping start water level RWL. When the water level of the water absorption well 10 falls. B-. From the area where the water level exceeds the pumping start water level RWL,
The normal drainage operation is performed until the water level drops to the pumping cutoff water level SWL through the pumping start water level RWL. B-. When the water level drops to the pumping cutoff water level SWL, the water / water switching valve 6A is opened to switch to the pumping cutoff operation, and the pumping cutoff operation is performed at a water level below the pumping cutoff water level SWL.
Prepare for the subsequent rise in water level.

By the way, in the conventional standby operation pump, even if the pump is switched from the normal drain operation to the pump interruption operation by the interruption of pumping in B-, water W remains in the pump,
Water and air are agitated in a state where a large load due to the weight of the residual water W is applied to the discharge side of the impeller 2. For this reason, vibrations and noises larger than those during normal drainage operation are generated, and various adverse effects are exerted on pump equipment. This vibration and noise become more remarkable as the pumping pipe 4 is longer (higher) and the amount of residual water W is larger. Further, since the residual water W drops through the small gap c between the inner circumference of the casing 3 and the outer circumference of the blade 2A of the impeller 2, it takes a long time to complete the drop of the residual water W. Therefore, it is operated under a heavy load for a long time. As a result, despite the pumping shutoff operation, the fuel consumption and the power consumption of the prime mover are not reduced and large energy is consumed.

[0005]

That is, in the conventional standby operation pump, since water remains in the pump even after switching to the pumping cutoff operation, larger vibration and noise than during normal drainage operation are generated. At the same time, since it takes a long time to complete the drop of the residual water, reduction of fuel consumption and electric power consumption of the prime mover is hindered and a large amount of energy is consumed. Therefore, the present invention suppresses the vibration and noise during the pumping cutoff operation by shortening the completion time of the residual water drop in the pump after switching to the pumping cutoff operation, and at the same time, reduces the fuel consumption or power consumption of the prime mover. It is an object of the present invention to provide a preceding standby operation pump that can reduce the amount and suppress energy consumption.

[0006]

In order to achieve the above object, the invention described in claim 1 has a casing in which an impeller fixed to a main shaft is rotatably accommodated, and a casing connected to an upstream side of the casing. A suction cover, a pumping pipe continuously provided on the downstream side of the casing, and a water / water switching system that is connected to the upstream side of the impeller and is connected to the upstream side of the impeller to switch between an atmosphere open state and an atmosphere cutoff state. A flap valve that is pushed up by the water flow during drainage operation to open the valve and that collapses and closes due to its own weight when the water flow is stopped after the pumping interruption is installed in the pipe, and this flap valve is seated on the valve seat of the flap valve. It is characterized by an electromagnet that adsorbs and holds the valve closed state and is equipped with a falling water system that closes during drainage operation and opens during pumping cutoff operation to drop residual water in the pump to the outside of the pump. . The invention described in claim 2
It is characterized in that the valve seat is inclined in a direction to shorten the opening / closing movement amount between the fully closed position and the fully open position of the flap valve.

According to the invention described in claim 1, the flap valve is pushed up by the water flow from the region where the water level exceeds the pumping start water level to the point where it passes through the pumping start water level and drops to the pumping cutoff water level. Since the falling water system is blocked, the regular drainage operation can be performed without lowering the pump efficiency. On the other hand, when the normal drainage operation is switched to the pumping cutoff operation, the water flow is stopped, so that the flap valve collapses due to its own weight and is pressed against the valve seat by the water pressure of the residual water in the pumping pipe to close the valve. This valve closed state can be maintained by an electromagnet. For this reason, unstable repeated opening and closing of the flap valve can be avoided, so that the state in which a large amount of residual water in the pump pipe is loaded on the impeller is shut off, and the load on the impeller is changed from the outlet of the impeller to the flap valve. Reduce to only a small amount of residual water present up to. In addition, by opening the falling water system, the residual water in the pump, that is, the large amount of residual water in the pumping pipe and the small amount of residual water existing from the impeller outlet to the flap valve can be pumped in a short time. Can be dropped outside. According to the invention described in claim 2, it is possible to shorten the time required for the flap valve at the valve closed position to rise to the valve open position (fully open position) at the time of switching from the pumping cutoff operation to the normal drainage operation.
Further, when switching from the normal drainage operation to the pumping cutoff operation, the time required for the flap valve at the valve open position (fully open position) to fall to the valve closed position can be shortened.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. The same or corresponding portions as those of the conventional example of FIG. 5 are designated by the same reference numerals, and detailed description thereof will be omitted. 1 to 4, a cross-shaped valve seat 9 is provided in the lower end portion of the pumping pipe 4. This valve seat 9
Has four arms extending outward in the radial direction with the main shaft 1 inserted through the central boss portion 9A, and the annular portion 9B on the outer periphery is fitted into the lower end portion of the pumping pipe 4 at equal intervals in the circumferential direction. It is fixed to the inner surface of the pumping pipe 4 by a plurality of bolts 9C, 9C, ..., which are screwed into the lower end of the pumping pipe 4 from the annular portion 9B side. Further, on the upper surface of the valve seat 9, four flap valves 1
2, 12 ... Are attached via a hinge 13 so as to be rotatable in the vertical direction.

The cross-shaped valve seat 9 is high at a central boss portion 9A surrounding the main shaft 1, and an annular portion 9B on the outer circumference from this point.
It is formed in a shape that inclines downward toward. That is, the valve seat 9 is inclined in such a direction as to shorten the opening / closing movement amount S from the fully closed position of the flap valves 12, 12, ... Shown by solid lines in FIGS. 3 and 4 to the fully opened position shown by phantom lines. An electromagnet 14 is provided below the valve seat 9. The electromagnet 14 is ON / OFF controlled by a signal output from the controller 8 based on the water level detection signal detected by the water level detection means 7.

As shown by the phantom lines in FIG. 4, each of the four flap valves 12, 12, ... Is in a fully open position in which the valve seat 9 is opened, and its center of gravity G passes through the vertical line C passing through the pin 13a of the hinge 13. It is located closer to the main shaft 1 than the main shaft 1 and is inclined toward the main shaft 1 side. Further, a rubber seat (valve seat) 12 is provided on the surface facing the valve seat 9 to cushion the impact when the valve is closed.
A is provided. Thus, the four flap valves 12, 12, ... Provided with the rubber sheet 12A are made of magnetic metal that can be attracted by the electromagnet 14. The rubber sheet 1 for the flap valves 12, 12 ...
Instead of 2A, a shock absorbing rubber sheet may be provided on the valve seat 9 side. In this case, the four flap valves 12, 12 ...
May be made of magnetic metal that can be attracted by the electromagnet 14 in the same manner as described above, or only the cross portion facing the arm of the cross-shaped valve seat 9 may be made of magnetic metal and the other may be made of non-magnetic metal. You may.

In FIG. 1 and FIG. 3, one water drop hole 15 is penetratingly provided at the lower end portion of the pumping pipe 4 and at the position where the guide vane 18 is provided in the casing 3.
The falling water pipes 16A and 16B are connected to the falling water hole 15, the falling water pipes 16A and 16B are joined, and the outlet thereof is open to the water intake well 10. Further, on-off valves 17A and 17B are provided in the middle of each. On-off valve 1
7A and 17B are composed of solenoid valves and the like whose opening and closing are controlled by a signal output from the controller 8 based on the water level detection signal detected by the water level detection means 7.

The operation of the preceding standby operation pump configured as described above will be described. When the water level of the water absorption well 10 rises. A-. Until the water level exceeds the pumping cutoff water level SWL and reaches the pumping start water level RWL, the air / water switching valve 6A is opened to perform in-air operation. In this case, the flap valves 12, 12
......, as shown by the solid lines in FIGS. 3 and 4, falls due to its own weight and closes the valve seat 9, and in this closed state, O of the electromagnet 14
It is held by the adsorption action of the lap valves 12, 12 by N control. Further, the on-off valves 17A and 17B are opened to open the falling water pipes 16A and 16B. A-. When the water level of the suction well 10 reaches the pumping start water level RWL, the steam switching valve 6A is closed. This starts the drainage operation. At the same time, the electromagnet 14 is turned off,
In addition, the on-off valves 17A and 17B are closed and the falling water pipes 16A and 1
Block 6B. At the start of the drainage operation, the flap valves 12, 12, ... Are pushed up by the water flow that rises up the casing 3, and the valve seat 14 is opened as shown by the phantom lines in FIGS. 3 and 4. That is, the pumping pipe 4 is opened. On-off valve 17
Since the water drop pipes 16A and 16B are closed by closing the valves A and 17B, it is possible to prevent a part of the pumped water from being discharged to the outside of the pump through the water drop pipes 16A and 16B. Therefore, at the water level equal to or higher than the pumping start water level RWL, the normal drainage operation (100% Q) can be performed without lowering the pump efficiency.

When the water level of the suction well 10 is lowered. B-. From the area where the water level exceeds the pumping start water level RWL,
The normal drainage operation is performed until the water level drops to the pumping cutoff water level SWL through the pumping start water level RWL. B-. When the water level is lowered to the pumping cutoff water level SWL, if the steam switching valve 6A is opened to switch to the pumping cutoff operation, the water flow in the casing 3 and the pumping pipe 4 is stopped. When the flow of water is stopped, the flap valves 12, 12 ... fall to the valve seat 9 side by their own weight to close the valve seat 9, and are pressed against the valve seat 14 by the water pressure of the residual water W in the pumping pipe 4, as shown in FIG. The valve is closed as shown by the solid line in FIG. At the same time, turn on the electromagnet 14
By performing the N control, the valve closed state of the flap valves 12, 12, ... Is maintained by the adsorption action of the electromagnet 14. For this reason, an unstable repeated opening / closing state of the flap valves 12, 12, ... Is avoided, so that the state in which a large amount of residual water W in the pumping pipe 4 is loaded on the impeller 2 is rapidly cut off, and the impeller is stopped. Two
Load to the flap valves 12, 12 ...
It is reduced to only a small amount of residual water w existing up to. Here, the on-off valve 17A is opened to open the water drop pipe 16A. As a result, the residual water W in the pumping pipe 4 can be dropped into the suction well 10 through the opened falling pipe 16A in a short time. Further, by opening the on-off valve 17B and opening the falling pipe 16B, the opened falling pipe 16B is opened.
The flap valves 12, 12 ... from the outlet of the impeller 2 through B.
Even a small amount of residual water w existing up to ... Can be dropped into the water absorption well 10 in a short time.

As described above, the residual water W in the pump can be dropped in a short time through the open fall pipes 16A and 16B, so that the vibration and noise during the pumping cutoff operation can be rapidly attenuated in a short time. At the same time, it is possible to reduce fuel consumption or electric power consumption of the prime mover and suppress energy consumption.

Moreover, the valve seat 9 is high at the boss portion 9A surrounding the main shaft 1, and is inclined downward from here toward the inner peripheral surface of the pumping pipe 4, and the flap shown by the solid line in FIGS. 3 and 4. Since the opening / closing movement amount S from the fully closed position of the valves 12, 12 ... to the fully open position shown by the phantom line is shortened, the flap valve in the valve closed position at the time of switching from the pumping cutoff operation to the normal drainage operation. It is possible to shorten the time required for 12, 12, ... to rise up to the valve open position (fully open position), so that the normal drainage operation can be started smoothly.
Further, when the normal drainage operation is switched to the pumping cutoff operation, the flap valve 12, which is in the valve open position (fully open position),
It is possible to shorten the time required for 12 ... to fall to the valve closed position, and to quickly shut off the state in which a large amount of residual water in the pumping pipe 4 is loaded on the impeller 2.

In the above-mentioned embodiment, the explanation has been given with the configuration using the four flap valves 12, 12, ...
The number of flap valves 12 to be used can be set by selecting an arbitrary number of three or more. Further, the description has been given of the configuration in which one water drop hole 15 is provided at each of the lower end portion of the pumping pipe 4 and the position where the guide vanes 18 are provided in the casing 3, but these positions are arranged at equal intervals in the circumferential direction. Plural drop holes 12 are provided, and drop pipes 16A, 16B are provided in each drop hole 12.
May be connected and opened and closed by the on-off valves 17A and 17B. Further, the valve seat 9 is formed separately from the pumping pipe 4, fitted in the lower end of the pumping pipe 4, and then fixed to the inner surface of the pumping pipe 4 by a plurality of bolts 9C, 9C. However, the valve seat 9 may be integrally formed inside the lower end of the pumping pipe 4. Furthermore, although the description is given of the configuration in which the water drop pipes 16A and 16B are merged and the outlet is opened to the water intake well 10, the water drop pipes 16A and 16B.
May be a separate pipe, or may be opened inside the suction cover 5 as shown by an imaginary line in FIG.

[0017]

As described above, according to the invention described in claim 1, when switching to the pumping cutoff operation, the residual water in the pump can be dropped from the opened drop hole in a short time. Vibration and noise during pumping cutoff operation can be rapidly attenuated in a short time, and fuel consumption or power consumption of the prime mover can be reduced to suppress energy consumption. Also, since the flap valve closed state is maintained by the adsorption action of the electromagnet, avoiding the unstable repeated opening / closing state of the flap valve, it is possible to quickly prevent the impeller from being loaded with a large amount of residual water in the pumping pipe. The load on the impeller can be reduced to only a small amount of residual water existing between the outlet of the impeller and the flap valve. According to the invention described in claim 2, at the time of switching from the pumping cutoff operation to the normal drainage operation, the flap valve in the valve closed position is shortened in the time required to rise to the valve open position (fully open position) to reduce the normal time. It is possible to smoothly start up to the drainage operation. In addition, when switching from normal drainage operation to pumping cutoff operation, shorten the time required for the flap valve in the valve open position (fully open position) to fall to the valve closed position, and reduce the large amount of water in the pumping pipe from the impeller. The state in which the residual water is loaded can be promptly shut off.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line AA in FIG.

FIG. 3 is an enlarged sectional view taken along line BB in FIG. 2;

FIG. 4 is an enlarged sectional view of a main part.

FIG. 5 is a schematic configuration diagram showing a conventional standby operation pump.

[Explanation of symbols]

 1 main shaft 2 impeller 3 casing 4 pumping pipe 5 suction cover 6 steam switching system 9 valve seat 12 flap valve 14 electromagnet 16A falling water pipe (falling water system) 16B falling water pipe (falling water system) 17A opening / closing valve (falling water system) 16B opening / closing valve (falling water) System) S flap valve opening / closing movement amount

Claims (2)

[Claims] 1. A casing in which an impeller fixed to a main shaft is rotatably accommodated, a suction cover continuously provided upstream of the casing, a pumping pipe continuously provided downstream of the casing, and a blade. It is equipped with a steam switching system that is connected to the upstream side of the vehicle and is switched between the atmosphere open state and the atmosphere shut off state.The pump pipe is pushed up by the water flow during the drainage operation to open the valve and shut off the pumping. There is a flap valve that falls down and closes due to its own weight when the subsequent water flow is stopped, and an electromagnet that adsorbs and holds the valve closed state of the flap valve is attached to the valve seat on which this flap valve is seated. The preceding standby operation pump, which is provided with a falling water system that is opened during the pumping cutoff operation to drop the residual water in the pump to the outside of the pump. 2. The preceding standby operation pump according to claim 1, wherein the valve seat is inclined in a direction that shortens the opening / closing movement amount between the fully closed position and the fully open position of the flap valve.