JP4468009B2 - Vertical shaft pump system and pump station - Google Patents

Description

  The present invention relates to a vertical shaft pump system and a pump station, and more particularly, to a vertical shaft pump system and a pump station suitable for a prior standby operation.

  Conventionally, as shown in FIG. 9, an impeller 2 is provided at the tip of a shaft arranged in the vertical direction, and air is sucked into the impeller 2 together with water, so that the operation can be performed even below the minimum operating water level LWL of the suction water tank 1. There was a vertical pump 3 that allowed it to continue. In this pump 3, a through-hole 5 is provided in the suction pipe 4 on the inlet side of the impeller 2, and an air pipe 6 that is opened to the outside air is attached to the through-hole 5. The amount of inflowing air was changed according to the water level to gradually reduce the amount of drainage, and the pump was idled at a lower water level.

In this way, for example, for rainwater drainage in large cities, the pump is started in advance according to rainfall information etc. regardless of the suction water level, and when the water level rises from the low water level, the total amount is increased while gradually increasing the water amount from the idle operation When the water level dropped from the high water level to the operation, it was possible to smoothly shift the operation from the full operation to the empty operation while gradually reducing the water amount. Such a pump is started at a water level LLLWL lower than the lower end of the casing (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 3-56895 (FIG. 5)

  Moreover, as shown in the schematic front sectional view of FIG. 10, there was a pump station including a plurality of pumps as described above. This machine is equipped with a plurality of pumps 3a, 3b, 3c in which the length of the trunk pipe and the position of the impeller are changed in order to prevent a water tank surge phenomenon due to sudden start or stop of drainage. The starting water level and the total operating water level were changed in stages.

  However, in the conventional pump as described above, for example, when the pump is installed in a closed type water tank, the air pressure in the sealed space above the water tank fluctuates due to the increase or decrease of the water level. There was a fluctuation error in the inflow start water level (pumping start water level, pumping stop water level), and there was a problem that pumping started at a water level different from the set water level or drained even at the pumping stop water level. In a pump station where a plurality of conventional vertical shaft pumps are attached, the pump 3a having the longest trunk pipe and the pump with the impeller attached to the bottom always starts draining first. Therefore, the operation frequency and operation time are excessive as compared with the other machines 3b and 3c. As described above, since the starting water level differs depending on the pump, there is a problem that the pump operation time is biased, the consumption of a specific pump becomes intense, and the maintenance work becomes difficult.

  In view of this, the present invention provides a vertical shaft pump system and a vertical pump system that are particularly suitable for a preliminary standby operation, in which an arbitrary or stable air pressure / air amount surely flows into a suction pipe disposed upstream of an impeller. The purpose is to provide a pump station equipped.

  In order to achieve the above object, the vertical shaft pump system according to the first aspect of the present invention is rotated by a rotary shaft 21 arranged in a vertical direction and sealed in a water tank 1 as shown in FIG. 1 or FIG. An impeller 20 that sucks in water, an upstream side of the impeller 20, a suction pipe 31 that flows water toward the impeller 20, one end connected to the suction pipe 31, and the other end the highest in the water tank 1 A vertical shaft pump 10 having an air pipe 60 that opens above the water level; and an on-off valve 71 having one end attached to a communication port 79 that communicates between the sealed water tank 1 and the outside of the water tank 1. Has been.

  If comprised in this way, since the on-off valve 71 attached to the said communication port 79 and the communication port 79 which connects the water tank 1 and the said water tank 1 outside is provided, the suction | inhalation arrange | positioned in the upstream of the impeller 20 Provided a vertical pump system that is particularly suitable for the standby standby operation, which can provide stable air pressure through the air pipe 60 in the pipe 31 and can arbitrarily change the inflow air pressure and air amount by adjusting the on-off valve 71. can do.

Further , the vertical shaft pump system may include a deodorizing filter 72 attached in series with the on-off valve 71. The deodorizing filter 72 is typically attached to the other end of the on-off valve 71.

Further, as described in claim 2 , the vertical shaft pump system according to claim 1 may be configured to include an automatic air vent valve 77 (see, for example, FIG. 6) attached in series with the on-off valve 71. . The automatic air vent valve 77 is typically attached to the other end of the on-off valve 71.

Further , in the vertical shaft pump system according to claim 1, the sealed water tank 1 communicates with the water tank 1a having a free surface under the water surface, and the water surface of the water tank 1a having the other end of the on-off valve 71 and the free surface. A pressure equalizing pipe 82 (for example, see FIG. 7) is provided to connect the upper part . Typically, the water tank 1a having a free surface is an open-air water tank, and is open to a space different from the space where the vertical shaft pump 10 is installed, for example.

Further, as described in claim 3 , the vertical shaft pump system according to claim 1 or 2 is configured to include a control mechanism 73 (for example, see FIG. 4) that automatically controls opening / closing of the opening / closing valve 71. May be.

In order to achieve the above object, a pump station according to a fourth aspect of the present invention provides a vertical pump system 101 according to any one of the first to third aspects (for example, FIG. 1); and a water tank 1 in which a plurality of vertical pumps 10a, 10b, and 10c are installed; a vertical pump so that the drainage start water levels of the multiple vertical pumps 10a, 10b, and 10c are two or more different water levels. 10a, 10b, and 10c are configured to open and close each on-off valve 71 (see, for example, FIG. 1).

  With this configuration, it is possible to provide a pump station with high maintainability that can achieve a uniform operation time of each pump while including a plurality of vertical shaft pumps.

As described above, according to the present invention, the impeller that rotates by the rotary shaft that is disposed in the vertical direction and sucks the water in the sealed water tank, and is disposed on the upstream side of the impeller, the water is directed toward the impeller. A vertical shaft pump having a suction pipe for flowing water, and an air pipe having one end connected to the suction pipe and the other end opened above the highest water level in the water tank; communication for communicating between the sealed water tank and the outside of the water tank An on-off valve with one end attached to the mouth ; a sealed aquarium communicates with the aquarium having a free surface below the surface of the water, and connects the other end of the on-off valve to the upper surface of the aquarium with the free surface because and a pressure equalizing pipe, a suction pipe disposed on the upstream side of the impeller, the odor is prevented from being released to the floor while the arbitrarily or stable pressure-air amount is reliably flows, especially prior waiting It is possible to provide a vertical shaft pump system suitable for operation. That.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol or a similar code | symbol is attached | subjected to the mutually same or equivalent member, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a schematic diagram illustrating a vertical shaft pump system 101 according to a first embodiment of the present invention, where (a) is a side sectional view and (b) is a plan view. The illustrated vertical shaft pump 10 is a pump for a prior standby operation, and is installed on a concrete floor 12 which is an installation table.

  Here, an example of a vertical pump 10 suitable for use in the first embodiment of the present invention will be described with reference to the cross-sectional view of FIG. In addition, unless otherwise indicated, each structure of the vertical shaft pump 10 demonstrated in this figure demonstrates as what is a structure common in 1st Embodiment to 4th Embodiment.

  Pre-standby operation, especially full-speed pre-standby operation, starts the pump in advance before rainwater flows into the pump water tank, runs idle at full speed, waits for the inflow of rainwater, and drains water as the water level (Level) L rises. At first, even if the water level drops, the pump is operated at full speed without stopping. Even if drainage is started, the vertical shaft pump 10 does not immediately discharge the required amount of water. Air is inhaled with water to enable low flow and idle operation.

  The structure of the vertical shaft pump 10 will be described with reference to the drawings. The vertical shaft pump 10 includes a pumping pipe casing (casing body) 33, a liner casing 32, and a suction pipe (suction bell) 31 arranged in the vertical direction from above. Each is fastened with a horizontal flange. These constitute a casing in a broad sense.

A rotary shaft 21 is arranged in the longitudinal direction (vertical direction) at the center of the casing, and an open impeller 20 is attached to the lower end of the rotary shaft 21 (may be a closed type). The liner casing 32 accommodates the impeller 20 with a slight gap from the outer periphery of the impeller 20 (the tip of the open blade). The vertical shaft pump 10 is a mixed flow pump. A mixed flow pump is used when the discharge head is relatively large. A guide vane 35 is disposed on the discharge side of the impeller 20 and on the inner side of the casing body 33.
An unillustrated axial flow pump or a spiral mixed flow pump may be used as the pump for the preceding standby operation, and the present invention can also be applied to an axial flow pump or a mixed flow pump. The axial flow pump is suitable when the flow rate is relatively large with respect to the discharge head.

  The casing body 33 includes a vertical trunk pipe portion 33a parallel to the rotary shaft 21, a curved pipe portion 33b bent in the horizontal direction above, and a horizontal pipe portion connected to the curved pipe portion 33b. The rotating shaft 21 penetrates. A bearing 22c and a seal (not shown) are disposed in the through portion. The rotary shaft 21 is supported at three points (or three or more points) by a bearing 22a and the bearing 22c disposed in the vicinity of the impeller 20 and a bearing 22b disposed between the two bearings. When the trunk pipe portion 33a is long, an intermediate bearing (not shown) similar to the bearing 22b may be further provided between the bearing 22b and the bearing 22c. In addition, a thrust bearing (not shown) supports a load in the vertical direction applied to the rotating shaft 21 (that is, the weight of the rotating body including the impeller 20 and the rotating shaft 21 and the fluid force applied to the impeller 20).

  A flange for installation is attached to the casing body 33, and the flange is installed on the concrete floor 12 that is an installation base with the flange. A flange is attached to the horizontal pipe portion of the casing body 33, and is connected to the discharge pipe 34 by the flange. The discharge pipe 34 is a pipe for guiding rainwater to a river or the sea and discharging it.

  An air suction hole 51 is formed in the casing located below the tip of the impeller 20. In FIG. 2, although the air suction hole 51 is illustrated as one piece, a plurality of air suction holes 51 may be provided. An annular air chamber (not shown) surrounding the casing may be provided, and the air chamber and the inside of the casing may be communicated with each other by a plurality of holes (holes) or slits formed in the entire circumference of the annular air chamber. . Such an air chamber surrounds the inner surface of the casing wall forming the suction pipe 31 and is formed outside the inner surface.

  In the present embodiment, the air suction hole 51 is formed in the upper part of the suction pipe 31 and in the vertical cylindrical part. It is located directly below the liner casing 32 and below the tip of the impeller 20.

  One end of an air pipe 60 is connected to the outside of the air suction hole 51 or an air chamber (not shown). The number of the air pipes 60 may be one as illustrated, but may be plural (for example, four may be used). Providing a plurality of air suction holes 51 or providing an annular air chamber is advantageous because air sucked from the air pipe 60 is uniformly distributed over the entire circumference of the suction pipe 31. In the first to fourth embodiments described with reference to FIGS. 1 to 7, the number of air tubes 60 is limited to two. However, the number of air tubes 60 is limited to this. It is as above-mentioned that it is not a thing.

  The other end (upper end) 61 of the air pipe 60 is opened above the highest water level HWL in the water tank 1. The highest water level HWL is a water level at which the water level can rise most in the water tank 1. Therefore, the upper end 61 of the air pipe 60 is not submerged in water.

  The impeller 20 is arrange | positioned below the below-mentioned minimum water level LWL. The entire main body portion of the impeller 20 or at least a part thereof, in particular, the tip end portion of the impeller 20 that sucks up water if there is a water level there, is disposed below the lowest water level LWL.

  A flat anti-rotation plate (not shown) is provided radially in the vicinity of the air suction hole 51, particularly on the inner surface of the casing (here, the suction pipe 31) between the impeller 20 and the air suction hole 51. You may form toward a direction (vertical direction).

  Next, the relationship between the vertical structure of the vertical pump 10 and the water level will be described. The highest water level HWL is the highest water level of the water tank 1 as described above. The water level L will not rise any further. Below that is the lowest water level LWL. This is a value peculiar to the pump installed in the specific water tank 1, and when the water level falls below this level, some problem occurs and the pump cannot continue to operate. Typically, below this level, the air is sucked in from the lower end of the suction pipe 31 in a vortex, causing vibration and noise, and the water level at which the operation cannot be continued.

  The design minimum water level Ld is at least equal to the water level LWL and is usually higher than that. The design minimum water level Ld is determined in accordance with the suction pipe diameter and the pump discharge flow rate.

  Below the design minimum water level Ld or the lowest water level LWL, there is a suction start water level SLWL of the impeller 20. This water level corresponds to the water level at the tip of the impeller 20. This is because when the water level rises from a low water level and the impeller 20 comes into contact with water, the air-water stirring is started and water is discharged soon.

  Below the suction start water level SLWL, there is an intake water level A1 corresponding to the height of the air suction hole 51. This corresponds to the upper end of the air suction hole 51. When the water level L decreases and reaches the water level LWL, the water level in the air pipe 60 that is lower than the water level L by the negative pressure h becomes the water level A1, and air begins to be sucked into the suction pipe 31 through the air pipe 60. .

  In the present embodiment, the height of the upper end of the air suction hole 51 is the intake water level A1. Below the intake water level A1, there is a water level A2 at the tip of the suction pipe 31.

  Further, the operation of the vertical shaft pump 10 will be described with reference to FIG. First, the vertical shaft pump 10 is started in a state where the water level is lower than A2. For example, it is predicted that the water level suddenly rises after a certain period of time, for example, when there is rainfall information indicating that heavy rain has occurred on the upstream side. In such a case, the vertical pump 10 for the preliminary standby operation is started in a state where the water level is lower than A2. This is the start of the preceding standby operation.

  The water level L in the water tank rises due to the inflow of rainwater and exceeds the lower end water level A2 of the suction bell. Even if the water level rises further and exceeds the water level A1, water is not yet sucked up. The impeller 20 is idling.

  When the water level L further rises and reaches the water level SLWL, the impeller 20 starts air-water agitation. Then begin to inhale water. At this time, air is sucked into the suction pipe 31 from the air suction hole 51 through the air pipe 60, so that the pump is not in the operation of discharging the total amount of water. That is, the vertical shaft pump 10 is in the air / water mixing operation. When the water level L further rises, the intake air amount gradually decreases, and the water amount increases instead. Eventually, when the water level L rises to the water level LWL, the air suction amount becomes zero, and the total water amount is discharged. That is, the steady operation is started.

  Furthermore, the water level rises to a water level between the water level LWL and the water level HWL, and the vertical shaft pump 10 continues the steady operation. Thereafter, when the water level L is lowered due to the drainage of the vertical shaft pump 10, air starts to be sucked through the air pipe 60 at the water level LWL (because the water level in the air pipe 60 reaches the intake water level A1). That is, the air / water mixing operation is started again. As the water level L decreases, the amount of intake air increases and the amount of water decreases instead. When the water level L further decreases and reaches the vicinity of the water level A1, the suction of water is finished, and the impeller 20 enters an idle operation state in which it is operated in the air. That is, the vertical shaft pump 10 is in an air lock state in which no water is sucked.

  In this way, the impeller 20 continues to idle in the air. When it continues to rain, the operation is continued, the water level L rises again, and the pump 10 starts to suck water when it reaches the water level SLWL as described above. In this manner, the preceding standby operation pump 10 can continue operation between the idle operation and the operation of the total water amount regardless of the water level of the water tank 1. The transition between idle and full water operation is smooth because the pump also draws in air.

  As described above, the water level L in the water tank rises due to the inflow of rainwater, and even if the water level exceeds A1, the water is not yet sucked up, but while the water has accumulated above the impeller 20 immediately after the water level is lowered. When the water level rises again, water suction starts at the water level A1, which is the height of the air suction hole 51.

  Here, with reference to the partial cross-sectional view of FIG. 3, the relationship between each water level and the water level Lc that sucks air spirally from the lower end of the suction pipe 31 will be clarified. In general, when designing a vertical shaft pump, an airlock water level is first specified by design specifications. That is, the water level drops from a high water level, and finally drains from the water level. Normally, the airlock water level is designed to match the water level A1 of the air suction hole 51. That is, the air suction hole 51 is provided at this position by design. Check the airlock water level during the test run. The actual airlock water level is not higher than the position of the air suction hole 51, and is lower than that, or almost the same height.

In general, the design specification also specifies a position at which drainage is started when the water level rises from a low water level, that is, the impeller tip position SLWL.
When the water level A1 is determined, the design water level Ld that is the total discharge water amount is calculated by the water level Ld = A1 + h. Here, h = hl + (v ² / 2g). The water head h may be determined by simple calculation by multiplying (v ² / 2g) by a predetermined coefficient.

Here, v is a water suction flow velocity obtained by (total amount of essential points water) / (suction part area of the suction pipe 31). (V ² / 2g) is a dynamic pressure generated by the flow of water calculated from Bernoulli's theorem. It may be called velocity head. Hl is a flow loss from the lower end A2 of the suction pipe 31 to the air suction hole 51. The loss head hl may be obtained by multiplying (v ² / 2g) by an empirical coefficient by simple calculation.

  The water level Ld is often obtained by simple calculation as described above. When the water level L is rising, the air is no longer sucked from the air suction holes 51, and the pump is fully discharged. When the water level L is decreasing, the entire amount is discharged and the air from the air suction hole 51 is discharged. It is the water level that inhalation begins.

  By design, the water level Ld provides a margin against the water level in which air is sucked in spirally from the lower end of the suction pipe 31. Therefore, air is not sucked from the lower end of the suction pipe 31 at this water level. That is, the water level Ld is at the same level as or higher than the water level LWL, usually the water level Lc.

  The water level Lc is a check item in determining the water level Ld as described above. That is, when the water level Ld obtained in the design process has become lower than the water level Lc, the design is corrected so that the water level Ld is equal to or higher than the water level Lc. For example, the suction pipe 31 is lengthened to lower the water level Lc.

  In the vertical shaft pump 10 of the present embodiment, the impeller 20 is disposed below the water level LWL and further below the water level Lc.

The water level Ld is calculated by the water level A1 + h and is h = hl + (v ² / 2g). Further, the positive pressure hp generated in the vicinity of the air suction hole 51 by the swirling flow generated in the suction pipe 31 is obtained. Considering h, h is as follows.
^{h = hl + (v 2 /} 2g) -hp

  According to the first to fourth embodiments, which will be described in detail below, an air pipe 79 (as a communication port that communicates between the sealed water tank 1 (see FIG. 2) and the outside of the water tank 1 ( For example, the upper part of the water surface inside the sealed water tank 1 is opened to the atmosphere or shut off from the atmosphere by opening and closing an on-off valve 71 (see, for example, FIG. 1) as an on-off valve having one end attached to the one end. Is done. Accordingly, the water level (the water level of the water tank 1) into which the vertical shaft pump 10 sucks air is governed by the above-mentioned formula of the water head h, but the water level of the water tank 1 is independent of the water level of the water absorption tank 1a as a water tank having a free surface. Can be determined. It is also possible to combine them. Here, the free surface refers to the water surface in contact with the atmosphere, and the free surface is subjected to atmospheric pressure.

  Returning to FIG. 1 again, the description of the vertical shaft pump system 101 according to the first embodiment of the present invention will be continued. As described above, the vertical shaft pump 10 is installed on a concrete floor 12 which is an installation table. Furthermore, the concrete floor 12 continuously forms a wall substantially perpendicular to the horizontal direction so as to surround the vertical shaft pump 10, and when the water surface reaches the suction pipe 31, the upper portion of the water surface is outside air. A sealed water tank 1 having a structure to be blocked is formed. A pump base 75 is disposed at a portion where the vertical shaft pump 10 is installed on the concrete floor 12 in order to ensure the airtightness in the water tank 1. The water tank 1 is configured such that an opening formed in a wall 12a near the bottom of the water tank 1 is connected to an open water absorption tank 1a whose upper surface is open to the atmosphere, and drainage flows into the water tank 1 from the opening. It is a so-called closed type water tank. In addition, the surface on the opposite side of the water tank 1 of the wall 12a of the water tank 1 in which the opening is formed, that is, the surface on the water absorption tank 1a side is inclined by about 45 ° with respect to the vertical direction, for example, and flows into the water tank 1. By making the drainage flow downward, it is configured so that vortices are less likely to occur during inflow.

  The vertical shaft pump system 101 according to the first embodiment includes the vertical shaft pump 10, and in this embodiment, includes two air pipes 60 (two or more) already described in FIG. 2. Further, an air pipe 79 as a communication port that communicates between the sealed water tank 1 and the outside of the water tank 1 is attached so as to penetrate the pump base 75. One end of the air pipe 79 formed in a substantially cylindrical shape is located in the space above the water surface in the sealed water tank 1, and the other end is outside the water tank 1, from the pump base 75. An opening / closing valve 71 is connected to an end located above the pump base 75.

  A deodorizing filter 72 is attached to the other end of the opening / closing valve 71. The open / close valve 71 opens and closes the valve so that when the valve is in an open state, the upper part of the water surface inside the sealed water tank 1 is opened to the atmosphere via the air pipe 79 and the deodorizing filter 72 and is in the closed state. Sometimes, the upper portion of the water surface is configured to be cut off from the atmosphere. Moreover, the deodorizing filter 72 uses activated carbon etc., and becomes an odor countermeasure in the case where the water surface upper part inside the water tank 1 is opened to the atmosphere. The deodorizing filter 72 only needs to be provided in series with the opening / closing valve 71, and may be inserted in the middle of the air pipe 79 or between the air pipe 79 and the opening / closing valve 71.

  When the water tank 1 is in a sealed state, that is, when the opening / closing valve 71 is in a closed state, the water level of the water absorption tank 1a and the water level of the water tank 1 do not necessarily match. That is, when the water level of the water absorption tank 1a rises, the water level of the water tank 1 rises according to the compression of the trapped air, but is kept at a lower water level than the water level of the water absorption tank 1a. Further, when the water level of the water tank 1a rises and the water level of the water tank 1 is raised as described later, the opening / closing valve 71 is closed, and then the water level of the water tank 1a is lowered, Since it is in a sealed state, the water level of the water tank 1 is slightly lowered, but is maintained at a higher water level than the water level of the water absorption tank 1a. On the other hand, when the water tank 1 has an open structure, that is, when the open / close valve 71 is in a closed state, the water level is the same as the water level of the water absorption tank 1a.

  Furthermore, a specific explanation is added. First, although the water level of the water absorption tank 1a is rising, in this Embodiment, when the opening / closing valve 71 is an open state, as the water level of the water absorption tank 1a rises, Since the air above the water surface is released to the outside air through the air pipe 79, the open / close valve 71, and the deodorizing filter 72 in this order, the air pressure in the water tank 1 becomes constant and the water level in the water tank 1 also rises.

  When the water level of the water absorption tank 1a rises to a predetermined water level determined in advance, the air pressure in the water absorption tank 1a is adjusted by closing the open / close valve 71 and closing the water tank 1 by the operation of an attendant or the like. be able to. For example, even if the water level in the water absorption tank 1a rises, the air pressure in the water tank 1 increases as the water level rises, so the water level in the water tank 1 can be prevented from rising.

  Next, when the opening / closing valve 71 is opened when the water level of the water absorption tank 1a has risen sufficiently, the water level of the water tank 1 rises to the same water level as the water absorption tank 1a. Next, when the water level of the water absorption tank 1a is lowered after the open / close valve 71 is closed, in the present embodiment, since the open / close valve 71 is closed and the water tank 1 is in a sealed state, the water level of the water absorption tank 1a. Even if the water level drops, the water level in the water tank 1 does not drop. By doing in this way, even if the water level of the water absorption tank 1a decreases, for example, the total water amount operation of the vertical shaft pump 10 can be continued.

  When the water level in the water absorption tank 1a is lowered to a predetermined level, the open / close valve 71 is opened by an operator or the like, so that the ambient air around the deodorization filter 72 is removed from the deodorization filter 72 and the open / close valve 71. The water level is lowered because it flows into the water tank 1 through the air pipe 79 in order and the pressure in the water tank 1 can be adjusted in the decreasing direction.

  That is, the air pressure (water level) in the water tank 1 is adjusted by opening and closing the open / close valve 71 according to the fluctuation of the water level of the water absorption tank 1a, so that the pumping start water level and the pumping stop water level can be arbitrarily changed. It is configured.

  As described above, according to the vertical shaft pump system 101 according to the first embodiment, since the on-off valve 71 is attached, the timing for opening or closing the upper portion of the water surface inside the sealed water tank 1 to the atmosphere. The airlock water level and the like can be freely set by arbitrarily determining the above, and further, the air can be supplied to the pump as required, and the optimum operation according to the actual state of the pump becomes possible.

  Further, conventionally, various operating water levels such as air-water mixing operation and air lock operation have been determined structurally. However, according to the present invention, various operating water levels can be adjusted by opening and closing the on-off valve 71. The operation water level such as the mixing operation and the air lock operation can be set regardless of the water level on the water absorption tank 1a side, and the adjustment range of the drainage amount is widened accordingly.

  FIG. 4 is a schematic diagram illustrating a vertical shaft pump system 102 according to the second embodiment of the present invention. In the first embodiment, the opening / closing valve 71 is configured to be controlled by an operation of an attendant or the like, that is, manually. However, in the second embodiment, a control mechanism 73 for automatically opening / closing the opening / closing valve 71 is provided. I have. Further, typically, a detector for detecting a water level or a pressure for transmitting a signal to the control mechanism 73 is provided, and a pressure detector 74 is provided here.

  A pressure detector 74 for measuring the pressure in the water tank 1 is disposed in the pump base 75 and detects a change in pressure at the upper part of the water surface in the water tank 1 due to a change in the water level of the water absorption tank 1a. The result is transmitted to the control mechanism 73. The control mechanism 73 is typically a computer such as a microcomputer. The control mechanism 73 receives the pressure measured by the pressure detector 74, and opens and closes an air valve to start or stop supplying air in accordance with the pressure in the water tank 1. The opening and closing of 71 is controlled. In this case, the opening / closing valve 71 may be an electric valve.

  According to the vertical shaft pump system 102 as the second embodiment described above, the water level of the water absorption tank 1a rises with the open / close valve 71 closed, and the pressure in the upper part of the water surface inside the water tank 1 is determined in advance. When the predetermined pressure is reached, the opening and closing valve 71 is changed from the closed state to the open state under the control of the control mechanism 73, whereby the pumping start water level and the like can be arbitrarily determined. Next, when both the water tank 1a and the water tank 1 rise to a certain water level, the open / close valve 71 is closed. With the open / close valve 71 closed, when the water level in the water absorption tank 1a drops and the pressure in the upper part of the water surface inside the water tank 1 drops to a predetermined pressure, the open / close valve 71 is controlled by the control mechanism 73. By switching from the closed state to the open state, it is possible to set an optimal operation such as an air-water mixing operation, an air lock operation, and a point-to-point total water amount operation according to the situation.

  FIG. 5 is a schematic diagram for explaining a vertical shaft pump system 102a according to a modification of the second embodiment of the present invention. This modification is different from the case of FIG. 4 in that a water level detector 76 for detecting the water level of the water absorption tank 1a is provided instead of the pressure detector 74 for detecting the pressure in the water tank 1. In this modification, the control mechanism 73 controls the open / close valve 71 according to the water level of the water absorption tank 1a detected by the water level detector 76 arranged on the water absorption tank 1a side, and automatically opens and closes the open / close valve 71. Configured to do. The water level detector 76 may detect a change in the water level based on a change in water pressure near the bottom of the water tank 1, or may be a float type using a float, an on / off type using a level switch, or the like.

  FIG. 6A is a schematic diagram illustrating a vertical shaft pump system 103 according to the third embodiment of the present invention. In the present embodiment, in addition to the configuration in the first embodiment, an automatic air vent valve 77 attached between the other end side of the on-off valve 71 and between the on-off valve 71 and the deodorizing filter 72 is provided. The automatic air vent valve 77 attached for the watertight structure countermeasure may be a float type automatic air vent valve, which is particularly effective when the water absorption level HWL on the water absorption tank 1a side is higher than the pump base 75. Note that the opening / closing valve 71, the automatic air vent valve 77, and the deodorizing filter 72 are not limited to this order, and may be connected in series. For example, the automatic air vent valve 77 may be an air pipe 79 or an air pipe 79 and the on / off valve 71. It may be between.

  FIG. 6B is a cross-sectional view illustrating the automatic air vent valve 77. When the water level on the water absorption tank 1a rises beyond the position of the pump base 75 when the opening / closing valve 71 is in the open state, the water level in the water tank 1 also increases as the water level on the water absorption tank 1a increases. Ascend upward. In such a case, water reaches the opening / closing valve 71. However, when water reaches the upper limit in the automatic air vent valve 77 attached to the other end of the opening / closing valve, the float 77a disposed in the automatic air vent valve 77 is also water. As the air pressure rises, it moves upward in the automatic air vent valve 77 and closes the air discharge port, that is, the port 77b on the deodorizing filter 72 side, so that drainage can be prevented from flowing out.

  FIG. 7 is a schematic diagram illustrating a vertical shaft pump system 104 according to the fourth embodiment of the present invention. In the first to third embodiments, the upper part of the water surface inside the sealed water tank 1 is opened to the atmosphere via the air pipe 79 and the deodorizing filter 72, or the surrounding outside air flows in. On the other hand, in the fourth embodiment, the sealed water tank 1 communicates with a water absorption tank 1a as a water tank having a free surface, and the other end of the open / close valve 71 and the water absorption tank 1a. A pressure equalizing pipe 82 is provided to connect the upper part of the water surface. In the present embodiment, the upper part of the water surface inside the water tank 1 is opened to the water on the water tank 1a side through the pressure equalizing pipe 82 connecting the water tank 1a and the open / close valve 71, or the air on the water tank 1a flows in. Is configured to do. In this case, it is not necessary to provide the deodorizing filter 72. For example, even if not only rainwater but also sewage flows into the water absorption tank 1a, the sewage odor is not released onto the floor.

  FIG. 8 is a diagram for explaining a pump station according to the fifth embodiment of the present invention, in which (a) is a schematic front sectional view showing a relationship between a plurality of vertical pumps in the pump station 105, and (b). These are typical front sectional drawings explaining installation of a vertical shaft pump in pump machine 105. In the pump station 105 in which the above-described vertical shaft pump system is used, a plurality of the preceding standby operation pumps as described above, here, the vertical shaft pumps are installed in the water tank. As shown in FIG. 8 (a), a plurality of vertical shaft pumps 10a, 10b, and 10c are partitioned by reinforced concrete aquarium partition walls 1b and 1c, respectively, and a water tank for each pump forms an independent sealed water tank. Yes.

  Further, for example, when the vertical pump system 102 according to the second embodiment is installed in the pump station 105, the control mechanism 73 of each of the plurality of vertical pumps 10a, 10b, 10c includes a plurality of vertical pumps 10a, 10b, The open / close valve 71 (for example, see FIG. 4) of each of the vertical shaft pumps 10a, 10b, and 10c is controlled so that the drainage start water level of 10c becomes two or more different water levels.

  Each of the vertical shaft pumps 10a, 10b, 10c changes the pressure of the control mechanism 73 when the pressure at the upper part of the water surface inside the water tank 1 changes as the water level of the water absorption tank 1a rises and reaches a predetermined pressure set in advance. The pumping start water level can be arbitrarily determined by changing the open / close valve 71 from the closed state to the open state by the control. Further, when the water level in the water tank 1a rises and the pressure in the upper part of the water surface inside the water tank 1 changes and drops to a predetermined pressure set in advance, the open / close valve 71 is opened by the control of the control mechanism 73. Since the water level in the water tank 1 is kept constant, the optimum operation such as the air-water mixing operation, the air lock operation, and the total water amount operation is continued depending on the situation regardless of the water level of the water absorption tank 1a. be able to.

  Moreover, as shown in FIG.8 (b), the vertical shaft pumps 10a, 10b, and 10c are the height which took distance in the height direction to some extent from the opening formed in the wall 12a which connected the water tank 1 and the water absorption tank 1a. It is installed so that the suction pipe 31 is located. When installed in this way, for example, when the opening / closing valve 71 is closed and the water level of the water absorption tank 1a is rising, the water level of the water tank 1 rises according to the compression of the trapped air, but from the pumping start water level Even at low water levels. When the pressure in the sealed water tank 1 is, for example, 0.1 MPa with the vertical pump 10a, 0.2 MPa with the vertical pump 10b, and 0.3 MPa with the vertical pump 10c, the open / close valves 71 are opened from the closed state. Then, if each is set to be the essential point total water amount operation, every time the water level of the water absorption tank 1a rises by 1 m, the total water amount operation is started one after another.

  Further, if the position of the bottom surface of the water absorption tank 1a is set to a position higher than the water tank 1, for example, substantially the same position as the suction pipe 31, the opening / closing valve 71 is provided when draining the water in the water absorption tank 1a. By making it closed, the water in the water absorption tank 1a can be drained until the water level becomes considerably low, or almost all the water in the water absorption tank 1a can be drained, and a vortex can be sucked like a conventional vertical shaft pump. Nor.

  In such operation of the pump station 105, when the amount of drainage is insufficient with one pump as the water level rises, the other pumps start draining one after another and the drainage operation with a plurality of units starts. Since the pump used here uses the vertical shaft pump 10 described above, the length of the trunk portion 33a (see FIG. 2) is the same, and the installation height is the same. Even if the installation height is the same, the water level at which water starts to be sucked can be varied. Further, since the start or end time of the air / water mixing operation can be adjusted to some extent regardless of the water level in the water tank, the order of starting the drainage can be arbitrarily set for each pump.

  According to the pump station 105 according to the fifth embodiment described above, the water level at which each pump starts to suck water can be arbitrarily changed even after the pump is installed, so that there is a bias in pump operation time. As a result, the consumption of a specific pump does not become severe and the maintenance work becomes difficult, and the construction and maintenance can be improved by making the pump operation time and shape uniform. In addition, when one of the pumps fails, it can be replaced by another unit, and even if the failed pump is replaced, the pump with the same specifications can be used, so the production delivery time can be shortened easily. is there.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. For example, in the pump station 105 described above, the control mechanism 73 has been described as automatically controlling the opening / closing of the opening / closing valve 71. For example, the vertical shaft pump according to the first, third, or fourth embodiment is described. Using the system, the water level of the water absorption tank 1a may be confirmed by visual inspection by an attendant or the like, and the open / close valve 71 may be manually opened / closed according to the water level. In this case, the pump station 105 having a simpler configuration can be obtained.

It is the schematic for demonstrating the vertical shaft pump system which concerns on the 1st Embodiment of this invention. 1 is a front sectional view of a vertical pump suitable for use in a vertical pump system according to a first embodiment of the present invention. It is a fragmentary sectional view of a vertical pump explaining the relation between each water level and the water level Lc that sucks air in a spiral shape from the lower end of the suction pipe. It is the schematic for demonstrating the vertical shaft pump system which concerns on the 2nd Embodiment of this invention. It is the schematic for demonstrating the modification of the vertical shaft pump system which concerns on the 2nd Embodiment of this invention. It is the schematic for demonstrating the vertical shaft pump system which concerns on the 3rd Embodiment of this invention. It is the schematic for demonstrating the vertical shaft pump system which concerns on the 4th Embodiment of this invention. It is typical front sectional drawing which shows the relationship of the some vertical shaft pump of the pump station which concerns on the 5th Embodiment of this invention. It is front sectional drawing of the conventional vertical shaft pump. It is typical front sectional drawing which shows the relationship of the several vertical shaft pump of the conventional machine place.

Explanation of symbols

10 Vertical shaft pump 20 Impeller 21 Rotating shaft 30 Casing 31 Suction pipe 51 Intake hole 60 Air pipe 71 Open / close valve 72 Deodorizing filter 73 Control mechanism 74 Pressure detector 76 Water level detector 77 Automatic air vent valve 79 Air pipe 82 Pressure equalizing pipe 101, 102 , 102a, 103, 104 Vertical shaft pump system 105 Pump station h Negative pressure head HWL Maximum water level Ld Design water level LWL Minimum water level Lc Water level SWL that sucks air in a swirl shape S1 Impeller suction start water level A1 Inlet port water level A2 Suction pipe lower end water level

Claims (4)

An impeller that rotates by a rotating shaft that is arranged in a vertical direction and sucks water in a sealed water tank; an intake pipe that is arranged on the upstream side of the impeller and flows the water toward the impeller; and A vertical shaft pump having an air pipe having one end connected to the suction pipe and the other end opened above the highest water level in the water tank;
An on-off valve having one end attached to a communication port communicating the sealed water tank and the outside of the water tank ;
The sealed water tank is communicated with the water tank and under water with a free surface, and a pressure equalizing pipe for connecting the water surface upper portion of the tank with the other end to the free surface of the on-off valve;
Vertical shaft pump system. An automatic air vent valve mounted in series with the on-off valve, closing the outlet when the water has reached the upper limit of the automatic air vent comprises an automatic air vent valve for preventing the outflow of water, to claim 1 The vertical pump system described. A control mechanism for automatically opening and closing the on-off valve;
The vertical shaft pump system according to claim 1 or 2 . The vertical shaft pump system according to any one of claims 1 to 3 , and
A water tank for installing a plurality of vertical shaft pumps;
The open / close valve of each of the vertical pumps is configured to open and close so that the drainage start water level of the plurality of vertical pumps becomes two or more different water levels;
Pump station.

Images