JP2018135764A - pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump which is adapted to achieve large capacity of a motor.SOLUTION: According to one aspect of the invention, a pump is provided which includes: a suction bell mouth; a discharge bowl; a lifting pipe; a discharge elbow; a pump main shaft extending in the lifting pipe; an impeller attached to the pump main shaft; a motor for rotating the pump main shaft; a motor housing which covers the motor and is at least partially located in an opening of the discharge elbow; and cooling fins provided on a side surface of the motor housing in the opening of the discharge elbow.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pump, and more particularly to a pump capable of continuing operation even when a motor is flooded due to a tsunami or storm surge.

In recent years, due to tsunamis caused by earthquakes, storm surges caused by huge typhoons, etc., it has become increasingly difficult to use equipment such as pumps submerged in ordinary pump stations. Therefore, there is a demand for a pump facility that can continue operation even in the event of a disaster such as a tsunami caused by an earthquake or a storm surge caused by a huge typhoon.
In order to enable continuous operation even when water enters the pump station due to a tsunami or storm surge, a vertical pump using a water-resistant motor used as a submersible pump or the like as a drive unit for the vertical pump has been proposed.

  However, the water-resistant motor of the prior art has a low pressure and low output (up to about 450 kW), but a relatively large capacity is required for sewage pump equipment and drainage pump equipment (flood control), and high pressure and high output (about 500 kW or more). Motor is required.

JP 2001-304163 A Japanese Patent No. 5552402

  When the capacity of the motor increases, the amount of heat generation increases, reaching the limit of the cooling capacity of the heat exchanging part considered in the prior art. Accordingly, the present invention has been made in view of such problems, and an object of the present invention is to provide a pump adapted to increase the capacity of a motor.

According to one aspect of the present invention, a suction bell mouth, a discharge bowl, a pumping pipe, a discharge elbow, a pump main shaft extending in the pumping pipe, an impeller attached to the pump main shaft, and the pump main shaft A motor housing that covers the motor and at least a part of which is in the discharge elbow opening, and a cooling fin provided on a side surface of the motor housing in the discharge elbow opening Are provided.
By providing cooling fins on the side surfaces of the motor housing, the cooling area is enlarged, and by installing cooling fins in the discharge elbow opening, heat generated from the motor can be efficiently cooled even when the capacity of the motor is increased.

A motor main shaft rotated by the motor is provided, and the pump main shaft is connected to the motor main shaft through a reduction gear.
By providing a reduction gear, it is not necessary to increase the number of motor poles even if the pump has a large capacity (large diameter (large water volume)), and the motor can be reduced in cost and size.

The speed reducer may be provided in a lower portion of the motor housing and in the discharge elbow opening.
In this case, it is desirable that the cooling fin is also provided on a side surface of the speed reducer.

The vertical position of the impeller is interlocked with the vertical position of the motor housing, the discharge elbow has a first flange, the motor housing has a second flange fastened to the first flange, The pump is a cylinder that is provided between the first flange and the second flange, and that holds a water stop ring between a horizontal surface that is in watertight contact with the lower surface of the second flange and an inner surface of the first flange. It is desirable to provide a holding member having a portion.
Thereby, even if it is a case where a reduction gear is provided in the lower part of a motor housing, the clearance gap between an impeller and a pump casing can be adjusted, suppressing water leakage.

The speed reducer may be provided outside the discharge elbow.
This facilitates maintenance of the reduction gear.

In this case, the speed reducer is provided on the upper surface of the motor housing, and the motor main shaft is a hollow shaft having a hollow inside and extends through the upper surface of the motor housing to the speed reducer. The pump main shaft may extend to the speed reducer in a cavity of the motor main shaft.
The cooling area is enlarged by providing cooling fins on the side of the motor, and the water sucked by the impeller cools the heat generated from the motor.

According to another aspect of the present invention, a suction bell mouth, a pump main shaft, an impeller attached to the pump main shaft, and a pump main shaft have a flange that defines an opening above the discharge elbow. A motor for rotating the motor, an adjustment base disposed on the flange and provided with a first opening and a second opening, and a bottom portion covering the motor and covering the first opening of the adjustment base. And a motor housing, wherein a pump is provided that can evacuate air in the discharge elbow through the second opening of the adjustment base.
The reliability related to the cooling performance (preventing deterioration of heat exchange efficiency) is improved by removing air from the discharge elbow.

The pump preferably includes a pipe that sucks water in the suction water tank, is connected to the second opening of the adjustment base, and drains the water in the discharge elbow to the suction water tank.
Thereby, the reliability regarding cooling performance (preventing deterioration of heat exchange efficiency) improves.

It is desirable to provide an automatic air vent valve whose lower part is connected to the second opening of the adjustment base.
Thereby, the air in a suction pipe can be extracted reliably.

  A pump suitable for a large capacity motor is realized.

1 is a schematic sectional view of a general vertical shaft mixed-flow pump. The schematic sectional drawing of the pump which concerns on 1st Embodiment. AA sectional drawing of FIG. The expanded sectional view in the broken line of FIG. The figure explaining the vertical direction adjustment of the impeller. The figure explaining the vertical direction adjustment of the impeller. The schematic sectional drawing of the pump which concerns on 2nd Embodiment. The schematic sectional drawing of the pump which concerns on 3rd Embodiment. FIG. 9 is a schematic sectional view of a pump that is a modification of FIG. 8. The schematic sectional drawing of the pump which concerns on 4th Embodiment.

  Embodiments according to the present invention will be specifically described below with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic sectional view of a general vertical axis mixed flow pump (hereinafter simply referred to as a pump). In this specification, the vertical shaft mixed flow pump is mainly exemplified, but the present invention is also applicable to other types of pumps such as a vertical shaft mixed flow / axial flow pump and a vertical shaft spiral mixed flow pump.

  The pump includes a pumping pipe 91, a discharge bowl 92, a suction bell mouth 13, a discharge elbow 1, a pump main shaft 2, a motor unit 3, and the like.

  The pumping pipe 91 is fixed to the floor opening by the pump base 91a, and the pumping pipe 91 extends to the underwater portion. A discharge bowl 92 is connected to the lower end of the pumping pipe 91, and a suction bell mouth 13 is connected to the lower end of the discharge bowl 92. Moreover, the discharge elbow 1 is connected to the upper part of the pumping pipe 91 in the floor upper part.

  The pump main shaft 2 extends in the vertical direction in the pumping pipe 91. The upper part of the pump main shaft 2 reaches the motor unit 3 installed on the motor base 3a. An impeller 4 is fixed to the lower part of the pump main shaft 2 via an underwater bearing 2a. As the pump main shaft 2 rotates, the impeller 4 rotates and water is sucked from the suction bell mouth 13. This water is discharged and discharged from the tip of the elbow 1.

  FIG. 2 is a schematic cross-sectional view of the pump according to the first embodiment of the present invention, and shows only the configuration of the upper floor. The pump includes a discharge elbow 1, a pump main shaft 2, a motor unit 3, an impeller 4, and the like. For example, the pump is installed in a pump station and guides water in a suction water tank to the discharge water tank.

  The discharge elbow 1 has a discharge elbow opening 11 extending in the vertical direction, and a first flange 14 that defines an opening is provided at the upper end. A discharge port 15 facing sideways is provided at the tip of the discharge elbow 1. The pump sucks the water in the suction water tank from the suction bell mouth 13 and drains it from the discharge port 15 to the discharge water tank via the impeller 4, a pumping pipe (not shown) and the discharge elbow 1. Further, a part of the water sucked from the suction bell mouth 13 is discharged and led to the upper part of the elbow opening 11, and a water-resistant motor (hereinafter simply referred to as a motor) integrated with the pump is cooled as described later. To do.

  The pump main shaft 2 extends in the vertical direction in the pumping pipe. The upper part of the pump main shaft 2 reaches the motor unit 3. An impeller 4 is fixed to the lower part of the pump main shaft 2. As the pump main shaft 2 rotates, the impeller 4 rotates and water is sucked from the suction bell mouth 13.

  The motor unit 3 includes a motor housing 31, an inner housing 32 inside the motor housing 31, a motor main shaft 33, a cooling water circulation blade 35, and the like. Covered by the motor inner housing 32 and the motor housing 31.

  The motor housing 31 includes a housing body 311 and a second flange 312 that protrudes outward from the outer peripheral surface thereof. The second flange 312 is fastened to the first flange 14 of the discharge elbow opening 11 with a bolt (not shown) or the like. The housing body 311 passes through the opening at the upper end of the discharge elbow opening 11. More specifically, the lower side of the housing body 311 from the second flange 312 is in the discharge elbow opening 11, and from the second flange 312. The upper side is outside (upper) the discharge elbow opening 11. Further, the water in the discharge elbow opening 11 does not enter the inside of the motor housing 31.

  The upper part of the motor main shaft 33 is in the inner housing 32 and passes through the lower surface of the inner housing 32 and the lower surface of the motor housing 31 and is connected to the pump main shaft 2.

  Between the internal housing 32 and the motor housing 31, there is a flow path through which internal cooling water different from the water from the discharge elbow opening 11 flows. The cooling water circulation blade 35 is fixed to the motor main shaft 33 between the bottom surface of the internal housing 32 and the bottom surface of the motor housing 31. A shaft seal 33 c is provided on the motor main shaft 33 in the inner housing 32 so that the internal cooling water does not enter the inner housing 32. As the motor main shaft 33 rotates, the cooling water circulation blade 35 rotates, whereby the internal cooling water circulates through the cooling water flow path, thereby cooling the heat generated from the motor.

  Here, when the capacity of the motor is increased (for example, about 500 kW), the heat generation is also increased. If it does so, the temperature of internal cooling water itself will become high.

  Therefore, the pump of this embodiment includes a plurality of cooling fins 5, and a horizontal sectional view (AA sectional view) thereof is shown in FIG. 3. As shown in FIG. 3, the cooling fin 5 is provided on the side surface of the motor housing 31 in the discharge elbow opening 11. More specifically, the cooling fin 5 is attached to the outer peripheral surface of the housing body 311 in the motor housing 31 and extends radially outward in the radial direction. The shape and number of the cooling fins 5 are not particularly limited, and the cooling fins 5 may be appropriately provided according to the heat generation amount of the motor and the cooling capacity of the cooling fins 5. For example, as the output of the motor is larger, it is preferable to provide more cooling fins 5 that are longer in the vertical direction.

  By providing the cooling fins 5 in this manner, even when the motor capacity is large and the heat generation amount is large, the cooling can be efficiently performed.

  When the capacity of the pump is large (the flow rate is large at a relatively low head), the number of poles of the motor becomes large. However, it is difficult to manufacture a motor with a large number of poles, and a custom design increases the cost. However, if the number of rotations of the motor can be reduced, the number of poles need not be increased.

  Therefore, the pump includes the speed reducer 6 having a structure integrated with the motor unit 3 (unitized), and the motor main shaft 33 and the pump main shaft 2 are connected via the speed reducer 6. The speed reducer 6 is provided below the motor housing 31 in the motor unit 3 and is provided in the discharge elbow opening 11. In FIG. 2, a waterproof planetary gear reducer having gears 62 (sun gear, planetary gear and internal gear) incorporated in the reducer housing 61 is assumed, but a parallel shaft gear reducer (for example, a helical gear or Other reduction gears such as a worm gear may be applied.

  In the reduction gear 6, a shaft seal 61 c is provided on the pump main shaft 2 in the reduction gear housing 61 so that water does not enter the reduction gear housing 61. Further, cooling fins may be provided on the side surface of the reduction gear housing 61, for example, the lower portion of the cooling fin 5 may extend from the motor housing 31 of the motor unit 3 to the side surface of the reduction gear housing 61.

  Next, a desirable mode for fastening the first flange 14 of the discharge elbow opening 11 and the second flange 312 of the motor unit 3 will be described. There is a gap between the impeller 4 and the inner surface of the pump casing, and the performance of the pump depends on the gap. The impeller clearance is adjusted by pulling up the impeller 4 after installing the pump. However, as shown in FIG. 2, it is difficult to lift the impeller 4 if the speed reducer 6 is provided directly below the motor unit 3. Therefore, the gap can be adjusted as follows by utilizing the fact that the impeller 4 attached to the pump main shaft 2 is interlocked with the vertical direction of the motor unit 3 (particularly, the motor housing 31).

  4 is an enlarged cross-sectional view of the vicinity of the first flange 14 of the discharge elbow opening 11 and the second flange 312 of the motor unit 3 (within the broken line in FIG. 2). The pump includes a rubber ring 71 and a holding member 72 that holds the rubber ring 71. The holding member 72 includes an annular part 721 that extends in a horizontal plane and a cylindrical part 722 that extends vertically downward from the inner peripheral end of the annular part 721. The annular portion 721 is disposed between the first flange 14 of the discharge elbow opening 11 and the second flange 312 of the motor unit 3. The lower surface and the upper surface of the annular portion 721 are in contact with the upper surface of the first flange 14 and the lower surface of the second flange 312, respectively. The outer surface of the cylindrical portion 722 is in contact with the inner surface of the first flange 14. One or a plurality of concave portions are provided on the outer surface of the cylindrical portion 722, and a rubber ring 71 is held as an elastic ring for water stoppage in each of the concave portions.

  The connection bolt 75 passes through the second flange 312, the annular portion 721, and the first flange 14, and is tightened in a watertight manner by sandwiching a gasket between the contact surfaces of the second flange 312, the annular portion 721, and the first flange 14. Is done. Further, by providing the rubber ring 71, it is possible to prevent water from leaking from between the lower surface of the annular portion 721 and the upper surface of the first flange 14.

  To adjust the impeller clearance, do as follows. First, the impeller 4 is rotated in the direction in which the jack bolt 73 is pulled up to the extent that the impeller 4 is to be raised, and a gap h is provided between the lower surface of the annular portion 721 and the upper surface of the first flange 14 (FIG. 5). Thereby, the 2nd flange 312 raises and the motor housing 31 whole of the motor part 3 raises. Along with this, the position of the impeller 4 also rises. (The opposite is true when lowering impeller 4)

  Subsequently, a height adjustment member (for example, an adjustment shim) 74 having an appropriate height is inserted into the gap h (FIG. 6). At this time, since the rubber ring 71 is on the inner surface of the first flange 14, water does not leak from between the lower surface of the annular portion 721 and the upper surface of the flange 14.

  Thus, by providing the rubber ring 71 on the holding member 72, the vertical position of the impeller 4 can be adjusted while preventing water leakage.

  As described above, in the first embodiment, since the cooling fin 5 is provided on the side surface of the motor housing 31 in the motor unit 3, the discharge elbow is provided even when the motor 34 has a large capacity and a large amount of heat generation. The water in the opening 11 can be efficiently cooled. In addition, by connecting the motor main shaft 33 and the pump main shaft 2 via the speed reducer 6, even if the capacity of the motor is increased, the number of poles does not increase and the manufacturing cost can be suppressed. Further, by providing the rubber ring 71 inside the first flange 14 of the discharge elbow opening 11, even if the speed reducer 6 is provided at the lower part of the motor unit 3, the impeller 4 is prevented from leaking water. The gap can be adjusted.

(Second Embodiment)
In the first embodiment described above, the speed reducer 6 is disposed in the elbow opening 11 that discharges at the lower part of the motor unit 3. On the other hand, in the second embodiment described below, the reduction gear 6 is disposed outside the elbow opening 11 by discharging at the upper part of the motor unit 3. Hereinafter, a description will be given focusing on differences from the first embodiment.

  FIG. 7 is a schematic cross-sectional view of a pump according to the second embodiment, in which only the upper part of the pump is depicted. The speed reducer 6 is disposed on the upper surface of the motor housing 31 of the motor unit 3. The motor main shaft 33 is a hollow shaft having a hollow inside, extends upward through the upper surface of the motor housing 31, and is connected to the speed reducer 6. The pump main shaft 2 is a solid shaft, extends upward in the cavity of the motor main shaft 33, and is connected to the speed reducer 6.

  Further, a downward-facing cooling fin 65 may be provided on the lower surface of the reduction gear housing 61. Similarly, a downward cooling fin 36 may be provided on the lower surface of the motor housing 31 of the motor unit 3.

  Thus, in the second embodiment, the speed reducer 6 is provided outside the discharge elbow opening 11. Therefore, maintenance of the reduction gear 6 becomes easy.

(Third embodiment)
In the case of a pump with a large capacity and a small head, the motor unit 3 may be smaller than the discharge elbow opening 11. The third embodiment to be described next assumes such a case. Hereinafter, the difference from the first and second embodiments will be mainly described.

  FIG. 8 is a schematic cross-sectional view of a pump according to the third embodiment. The motor housing 31 in the motor unit 3 is smaller than the inner diameter of the discharge elbow opening 11. Therefore, the pump is provided with an adjustment base 8. The adjustment base 8 has an annular shape, and the outer peripheral portion is disposed on the first flange 14 and fixed.

  The motor housing 31 has a bottom surface 313 having two levels, and covers the opening (first opening) of the adjustment base 8. More specifically, the lower stage 313 a of the bottom surface 313 is fitted in the opening of the adjustment base 8. Cooling fins 81 may be provided on the lower surface of the lower stage 313a. The outer peripheral portion of the upper stage 313b in the bottom surface 313 is disposed and fixed on the inner peripheral portion of the adjustment base 8. Although the motor main shaft (not shown) penetrates the bottom surface 313, the water in the discharge elbow opening 11 does not enter the motor unit 3.

  In such a structure, water may stagnate or air may accumulate in the lower part of the adjustment base 8 or the bottom surface 313, and the motor unit 3 may not be efficiently cooled even if the cooling fins 81 are provided.

  Therefore, in the present embodiment, the adjustment base 8 is provided with an opening 8a (second opening). Air in the discharge elbow opening 11 can pass through the opening 8a to the outside of the pump. The pump may also include a pipe 82 connected to the opening 8 a of the adjustment base 8. Water in the vicinity of the first flange 14 and the cooling fins 81 is drained through the pipe 82 to the suction water tank.

As described above, in the third embodiment, the opening 8 a is provided in the adjustment base 8 to connect the pipe 82. Therefore, air can escape and water can flow, improving reliability.
In addition, as shown in FIG. 9, you may enlarge the diameter of the cooling part in the discharge elbow opening part 11. As shown in FIG. By enlarging the cooling portion, the lower pipe 83 can be provided, and drainage is possible even when the pipe 82 is clogged with floating dust or the like, and reliability is improved.

(Fourth embodiment)
In the third embodiment described above, the pipe 82 is provided in the opening 8 a of the adjustment base 8. On the other hand, in the fourth embodiment described below, an automatic air vent valve is provided in the opening 8a. Hereinafter, the difference from the third embodiment will be mainly described.

  FIG. 10 is a schematic cross-sectional view of a pump according to the fourth embodiment. The pump is provided with an automatic air vent valve 9. The lower part of the automatic air vent valve 9 is connected to the opening 8 a of the adjustment base 8.

  Such an automatic air vent valve 9 can be installed when the pressure in the elbow 1 discharged during normal operation does not become negative and the flow of cooling water can be secured without a return pipe to the suction water tank.

  Since air is extracted from the top of the discharge elbow opening 11, the reliability is high. Even if the motor unit 3 is submerged and water is accumulated above the automatic air vent valve, if the discharge water tank has a lower water level, the water discharged from the elbow 1 is discharged through the automatic air vent valve 9 and drained. You can also

  The embodiment described above is described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention should not be limited to the described embodiments, but should be the widest scope according to the technical idea defined by the claims.

DESCRIPTION OF SYMBOLS 1 Discharge elbow 11 Discharge elbow opening 13 Suction bell mouth 14 1st flange 15 Discharge port 2 Pump main shaft 2a Underwater bearing 3 Motor part 3a Motor base 31 Motor housing 311 Housing main body 312 2nd flange 313 Bottom 313a Lower 313b Upper 32 Inner housing 33 Motor spindle 35 Cooling water circulation blade 36 Cooling fin 4 Impeller 5 Cooling fin 6 Reducer 61 Reducer housing 65 Cooling fin 71 Rubber ring 72 Holding member 721 Ring portion 722 Cylindrical portion 73 Jack bolt 74 Height adjustment member 75 Connection Bolt 8 Adjustment base 8a Second opening 81 Cooling fin 82 Pipe 83 Lower pipe 9 Automatic air vent valve 91 Pumping pipe 91a Pump base 92 Discharge bowl

Claims (5)

Suction bell mouth, discharge bowl, pumping pipe, discharge elbow,
A pump main shaft extending in the pumping pipe;
An impeller attached to the pump main shaft;
A motor for rotating the pump main shaft;
A motor housing that covers the motor and at least a portion is in the opening of the discharge elbow;
And a cooling fin provided on a side surface of the motor housing in the opening of the discharge elbow. A motor spindle rotated by the motor;
The pump according to claim 1, wherein the pump main shaft is connected to the motor main shaft via a reduction gear.   The pump according to claim 2, wherein the speed reducer is provided in a lower portion of the motor housing and in an opening of the discharge elbow. The height position of the impeller is linked with the height position of the motor housing,
The discharge elbow opening has a first flange;
The motor housing has a second flange fastened to the first flange;
The pump
A horizontal plane provided between the first flange and the second flange and in contact with the lower surface of the second flange in a watertight manner;
The pump according to claim 3, further comprising a holding member having a cylindrical portion that holds a water stop ring between the inner surface of the first flange.   The pump according to any one of claims 1 to 4, wherein the water sucked by the impeller cools heat generated from the motor by providing the cooling fin.