JP7359524B2 - vertical shaft pump - Google Patents

Description

The present invention relates to a vertical shaft pump capable of cooling a bearing that rotatably supports a main shaft having an impeller attached to its lower end.

A vertical shaft pump has a main shaft with an impeller attached to the lower end rotatably supported by a bearing, and usually lubricating water is supplied to the bearing to cool it in order to suppress heating of the bearing. Conventionally, this lubricating water is externally pressurized water such as tap water, and is supplied by an external pump for externally pressurized water installed outside the vertical shaft pump.

For example, Patent Document 1 describes a vertical shaft pump device that includes a cooling mechanism that supplies cooling water (lubricating water) to a bearing that supports a main shaft covered with a protection tube.
This vertical pump device is equipped with a water supply tank, a water supply pump, a water supply pipe, and a cooling control unit. It is designed to be supplied from the bottom end of the

Furthermore, Patent Document 2 includes a protective tube that encloses and fixes an underwater bearing that supports a rotating shaft, and a communication tube that communicates the protective tube with the outside of the vertical shaft pump, and supplies lubricating water from the communication tube into the protective tube. A submersible bearing structure for conveying water is described. Even in this submersible bearing structure, lubricating water is stored in a water tank provided on the installation floor outside the vertical shaft pump, and is sent to the communication pipe by the submersible pump.

Japanese Patent Application Publication No. 2014-190207 Japanese Patent Application Publication No. 2016-17420

In the above conventional techniques, the following problems remain.
In the conventional techniques described in Patent Documents 1 and 2, it is necessary to install an external pump in order to supply lubricating water as water under other pressure such as tap water, which is disadvantageous in that the cost becomes high. There is also a method of integrating the pump with a submersible motor, but since the submersible motor has poor durability and is expensive, the cost also increases. Furthermore, in places where water pipes are not installed, it is difficult to supply tap water as lubricating water.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a vertical shaft pump that does not require an external pump and is capable of cooling bearings at low cost.

The present invention employs the following configuration to solve the above problems. That is, the vertical shaft pump according to the first invention includes a main shaft that has an impeller attached to its lower end and is rotationally driven, and a casing that rotatably supports the main shaft via a bearing, and the casing has the The main shaft above the impeller and the bearing are arranged inside to protect the main shaft and the bearing, and the protection pipe is arranged inside to protect the main shaft, and the outer casing part houses the main shaft and the main shaft inside. It is characterized by being provided with a fluid cooling mechanism that circulates and cools the inside and outside of the tube.

This vertical shaft pump is equipped with a fluid cooling mechanism that circulates and cools the fluid inside the protection tube between the inside and outside of the protection tube, so there is a gap between the inside of the protection tube and the outside of the protection tube where raw water flows. The fluid circulated and cooled by the fluid cooling mechanism can cool the bearing inside the protection tube without using an external pump.

In the vertical shaft pump according to a second invention, in the first invention, the fluid cooling mechanism includes a rotary vane that is attached to the main shaft and rotates with rotation of the main shaft to cause the fluid in the protection tube to flow upward. one end is connected to the protective tube above the rotary blade part, the other end is connected to the protective tube below the rotary blade part, and extends between the protective tube and the outer casing part. It is characterized by comprising a fluid circulation pipe arranged in the same direction.
That is, in this vertical shaft pump, the fluid cooling mechanism includes a rotary vane section attached to the main shaft and a fluid circulation pipe extending between the protection tube and the outer casing section. The rotating blade portion and the fluid circulation piping circulate the fluid inside and outside the protection tube, and the fluid is cooled. First, when the rotary vane within the protection tube rotates due to rotation of the main shaft, fluid within the protection tube is sent out above the rotary vane. The fluid flowing upward within the protection tube flows from one end of the fluid circulation piping through the fluid circulation piping disposed between the protection tube and the outer casing part. At this time, the fluid in the fluid circulation pipe is cooled by radiating heat to the raw water flowing inside the outer casing part. The fluid cooled within the fluid circulation pipe can be returned to the protection pipe from the other end of the fluid circulation pipe, thereby cooling the bearing within the protection pipe.

A vertical shaft pump according to a third invention is characterized in that, in the second invention, a plurality of the fluid cooling mechanisms are provided in the extending direction of the main shaft.
In other words, in this vertical shaft pump, a plurality of fluid cooling mechanisms are provided in the extending direction of the main shaft, so that the fluid in the protection tube can be more effectively cooled and the bearings can also be cooled by the plurality of fluid cooling mechanisms. can.

In the vertical shaft pump according to a fourth aspect of the invention, in the second or third aspect, the bearing is provided at least above and below the rotary vane section, and one end of the fluid circulation pipe is connected to the rotary vane section. The other end of the fluid circulation pipe is arranged near the upper part of the bearing located below the rotary blade part. shall be.
That is, in this vertical shaft pump, one end of the fluid circulation piping is arranged near the bottom of the bearing located above the rotary vane, and the other end of the fluid circulation piping is located below the rotary vane. Since the fluid that has become hot near the bottom of the upper bearing is guided from one end of the fluid circulation piping to the outside of the protection pipe, the heat is radiated to the raw water and cooled, and the fluid is returned to the bottom. By returning it near the top of the bearing, the fluid between the upper and lower bearings can be efficiently circulated and the bearing can be cooled effectively.

A vertical shaft pump according to a fifth invention is characterized in that, in any one of the first to fourth inventions, the fluid is air.
That is, in this vertical shaft pump, since the fluid is air, there is no need for special lubricating water, etc., resulting in low cost and easy maintenance.

According to the present invention, the following effects are achieved.
That is, according to the vertical shaft pump of the present invention, a fluid cooling mechanism is provided that circulates and cools the fluid inside the protection tube between the inside and outside of the protection tube. The bearing inside the protection tube can be cooled without using an external pump by the cooled fluid that is circulated between the outside of the tube and the fluid cooling mechanism.
Therefore, the vertical shaft pump of the present invention does not require an external pump, can be constructed at low cost, and can cool the bearings even in locations where water pipes are not installed.

FIG. 1 is a sectional view showing an embodiment of a vertical shaft pump according to the present invention. In this embodiment, it is a sectional view showing the main part of the vertical shaft pump. In this embodiment, it is a sectional view showing the lower part of the protection tube.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the vertical shaft pump in this invention is described based on FIGS. 1-3.

The vertical shaft pump 1 in this embodiment is, for example, an emergency drainage pump for a river, and as shown in FIGS. 3 rotatably supported.
The casing 5 includes a protective tube 10A that arranges and protects the main shaft 3 and bearing 4 above the impeller 2 inside, and an outer casing part 10B that houses the protective tube 10A together with the main shaft 3 inside. ing.

Moreover, the vertical shaft pump 1 of this embodiment is provided with a fluid cooling mechanism 15 that circulates and cools the fluid inside the protection tube 10A between the inside and outside of the protection tube 10A.
The fluid cooling mechanism 15 includes a rotary blade part 15a that is attached to the main shaft 3 and rotates with the rotation of the main shaft 3 to cause the fluid in the protection tube 10A to flow upward, and a protection pipe 10A above the rotary blade part 15a. Fluid circulation piping 15b has one end connected to the inside, and the other end connected to inside the protective tube 10A below the rotary blade part 15a, extending between the protective tube 10A and the outer casing part 10B. It is equipped with

Further, a plurality of fluid cooling mechanisms 15 are provided in the direction in which the main shaft 3 extends. In this embodiment, the fluid cooling mechanisms 15 are provided at five locations in line in the extending direction of the main shaft 3.
The bearings 4 are provided at least above and below the rotating blade portion 15a, respectively. That is, in this embodiment, five rotary blade portions 15a are attached to the main shaft 3 at intervals.

One end of the fluid circulation pipe 15b is arranged near the lower part of the bearing 4 located above the rotating blade portion 15a, and the other end of the fluid circulation pipe 15b is located below the rotating blade portion 15a. It is arranged near the upper part of the bearing 4.
The fluid is air. That is, the space between the bearings 4 in the protection tube 10A forms an airtight air chamber together with the fluid circulation piping 15b.

The rotating blade portion 15a is made of, for example, stainless steel, and is attached to the outer peripheral surface of the main shaft 3. The rotary blade portion 15a has a propeller shape that can push fluid from below to above when rotated in the same direction as the rotation direction of the main shaft 3.
The fluid circulation pipe 15b is made of, for example, a highly corrosion-resistant metal such as stainless steel.

The vertical shaft pump 1 of this embodiment is a mixed flow pump in which the flow discharged from the impeller 2 is within a conical plane centered around the centerline of the main shaft 3.
The casing 5 has a cylindrical shape with a water suction port 5a at the lower end, and a discharge pipe 14 is connected to the upper side.

Conventional emergency drainage pumps have an integrated structure of "pump + submersible motor" and are installed inside the column by hanging from the top with turnbuckles, chains, etc., but in this embodiment, the protective tube 10A is connected to the bearing 4. The main shaft 3 is rotatably supported via the main shaft 3, and the strength is set to support the load of the main shaft 3 installed in a suspended state.

For this reason, since the pump body part below the main shaft 3 is suspended and supported by the high-strength protection tube 10A, when converting an existing vertical shaft pump to the vertical shaft pump 1 of this embodiment, the existing discharge pipe can be used and modified. and can be reused. Additionally, the existing lower column can also be used.
In the vertical shaft pump 1 of this embodiment, an outdoor vertical shaft fully enclosed external fan electric motor M is installed above the discharge pipe 14 to rotate the main shaft 3 without using a submersible motor. By employing the above-ground electric motor M in this way, reliability and lifespan are improved compared to underwater motors.

The outer casing portion 10B is constructed by connecting a plurality of cylindrical bodies in the axial direction.
Further, in the vertical shaft pump 1 of the present embodiment, the bearing 4 includes a plurality of ring-shaped intermediate bearing bodies 4a sandwiched between the divided outer casings 10B, and these intermediate bearing bodies 4a provide strength against loads, etc. It supports vibrations, etc.
In addition, the upper part of the protection tube 10A is supported by the upper part of the discharge pipe 14 in a penetrating state.

Moreover, the protection tube 10A prevents the drainage water (raw water) in the casing 5 from entering the protection tube 10A.
That is, as shown in FIG. 3, a mechanical seal 18 that supports the lower end of the main shaft 3 is provided at the lower part of the protection tube 10A, and the mechanical seal 18 provides an airtight and watertight structure. Therefore, the mechanical seal 18 prevents the waste water (raw water) outside the protection tube 10A from entering into the protection tube 10A.

The vertical shaft pump 1 of this embodiment is installed in a suspended manner with the flange portion 5b at the top of the casing 5 fixed to a pump base (base plate) 19b attached to an installation hole 19a formed in an installation floor 19 at the top of a suction water tank. ing.

In this way, the vertical shaft pump 1 of this embodiment is provided with the fluid cooling mechanism 15 that circulates and cools the fluid inside the protection tube 10A between the inside and outside of the protection tube 10A. The bearing 4 inside the protection tube 10A can be cooled without using an external pump by the cooled fluid that is circulated by the fluid cooling mechanism 15 between the inside of the protection tube 10A and the outside of the protection tube 10A through which the raw water flows.
In particular, since the fluid is air, there is no need for special lubricating water, resulting in low cost and easy maintenance.

Further, since the fluid cooling mechanism 15 includes a rotating blade portion 15a attached to the main shaft 3 and a fluid circulation pipe 15b extending and disposed between the protection tube 10A and the outer casing portion 10B. The fluid is circulated inside and outside of the protection tube 10A by the rotary vane portion 15a and the fluid circulation piping 15b, and is cooled. First, when the rotating blade portion 15a in the protection tube 10A rotates due to the rotation of the main shaft 3, the fluid in the protection tube 10A is sent out above the rotating blade portion 15a.

The fluid flowing upward in the protective tube 10A flows from one end of the fluid circulation piping 15b into the fluid circulation piping 15b disposed between the protective tube 10A and the outer casing portion 10B. At this time, the fluid in the fluid circulation pipe 15b is cooled by radiating heat to the raw water flowing in the outer casing part 10B. The fluid cooled within the fluid circulation piping 15b is returned to the protection tube 10A from the other end of the fluid circulation piping 15b, thereby cooling the bearing within the protection tube 10A.

Furthermore, since a plurality of fluid cooling mechanisms 15 are provided in the extending direction of the main shaft 3, the plurality of fluid cooling mechanisms 15 can more effectively cool the fluid in the protection tube 10A and also cool the bearing 4. I can do it.
Further, one end of the fluid circulation pipe 15b is arranged near the lower part of the bearing 4 located above the rotating blade portion 15a, and the other end of the fluid circulation pipe 15b is located below the rotating blade portion 15a. Since the fluid that has become hot near the bottom of the upper bearing 4 is guided to the outside of the protection tube 10A from one end of the fluid circulation pipe 15b, the heat is radiated to the raw water and cooled. By returning the fluid again to the vicinity of the upper part of the lower bearing 4, the fluid can be efficiently circulated between the upper and lower bearings 4, and the bearing 4 can be effectively cooled.

Note that the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention.
For example, as described above, it is preferable to use air as the fluid, but if it is necessary to obtain a higher cooling effect, lubricating water such as antifreeze may be used as the fluid.

DESCRIPTION OF SYMBOLS 1... Vertical shaft pump, 2... Impeller, 3... Main shaft, 4... Bearing, 5... Casing, 10A... Protection tube, 10B... Outer casing part, 15... Fluid cooling mechanism, 15a... Rotating vane part, 15b... For fluid circulation Piping

Claims (4)

A main shaft with an impeller attached to the lower end and driven to rotate,
and a casing rotatably supporting the main shaft via a bearing,
a protection tube in which the casing protects the main shaft and the bearing above the impeller by arranging the main shaft and the bearing therein;
an outer casing part in which the protection tube is housed together with the main shaft,
A fluid cooling mechanism is provided that circulates and cools the fluid inside the protection tube between the inside and outside of the protection tube ,
The fluid cooling mechanism includes a rotary blade portion that is attached to the main shaft and rotates with the rotation of the main shaft to cause the fluid in the protection tube to flow upward;
One end is connected to the protection tube above the rotating blade portion, the other end is connected to the protection tube below the rotating blade portion, and extends between the protection tube and the outer casing portion. A vertical shaft pump characterized in that it is equipped with fluid circulation piping arranged in the vertical axis . The vertical shaft pump according to claim 1 ,
A vertical shaft pump, wherein a plurality of the fluid cooling mechanisms are provided in an extending direction of the main shaft. The vertical shaft pump according to claim 1 or 2 ,
The bearings are provided at least above and below the rotating blade portion, respectively,
One end of the fluid circulation pipe is disposed near a lower portion of the bearing located above the rotating blade portion, and the other end of the fluid circulation pipe is located below the rotating blade portion. A vertical shaft pump characterized by being placed near the top of the bearing. A main shaft with an impeller attached to the lower end and driven to rotate,
and a casing rotatably supporting the main shaft via a bearing,
a protection tube in which the casing protects the main shaft and the bearing above the impeller by arranging the main shaft and the bearing therein;
an outer casing part in which the protection tube is housed together with the main shaft,
A fluid cooling mechanism is provided that circulates and cools the fluid inside the protection tube between the inside and outside of the protection tube,
A vertical shaft pump characterized in that the fluid is air.

Images