JP2021099083A - Foreign substance removal mechanism and pump - Google Patents

Abstract

To provide a foreign substance removal mechanism that has a small effect on pump efficiency.SOLUTION: A foreign substance removal mechanism 20 is comprised in a vertical shaft mixed flow pump comprising a casing 17, and an impeller 11 to be rotated inside the casing 17, removes a foreign substance existing in a gap between the casing 17 and a blade 19 of the impeller 11, and comprises: an opening part 21 provided so as to cause the inside and the outside of the casing 17 to communicate with each other; a discharge mechanism 22 opposed to the blade 19 via the opening part 21, and for discharging a foreign substance existing in the gap between the casing 17 and the blade, to the outside from the inside of the casing 17 via the opening part 21; and a storage part 23 arranged so as to cover the opening part 21 while the discharge mechanism 22 exists therein on the outside of the casing 17, and for storing the foreign substance discharged by the discharge mechanism 22.SELECTED DRAWING: Figure 2

Description

The present invention is provided in a pump having a casing and an impeller rotating inside the casing, and a foreign matter removing mechanism for removing foreign matter existing in a gap between the casing and the blades of the impeller, and the foreign matter removing. Regarding pumps equipped with a mechanism.

Pumps installed at stormwater drainage pump stations pump water mixed with foreign matter, so foreign matter may get entangled in the impeller. Since such entanglement of foreign matter has an adverse effect on pump efficiency, conventionally, foreign matter in sewage flowing from a sewage inflow pipe is captured by a strainer like the manhole pump device of Patent Document 1, or for sewage of Patent Document 2. Like a pump, an annular convex portion is provided on the inner peripheral surface of the pump casing, and the trailing edge of the impeller blade is provided with a concave portion having a cross-sectional shape complementary to the annular convex portion, and foreign matter is cut by these. Is being done.

However, since the manhole pump device of Patent Document 1 has a configuration in which foreign matter is removed by backwashing the strainer, in addition to the sewage inflow pipe having the strainer, the check valve for backwashing is applied to the sewage inflow pipe. Space is required to provide a valve or the like. In the sewage pump of Patent Document 2, it is necessary to newly design the blades in order to make the blades a shape different from the usual one. In any case, since measures are taken against foreign substances in the path through which sewage is passed, the effect on pump efficiency is large.

Japanese Unexamined Patent Publication No. 2007-40143 JP-A-2019-100271

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a foreign matter removing mechanism and a pump having a simple structure and having a small influence on the pump efficiency.

A feature of the foreign matter removing mechanism according to the present invention for achieving the above object is provided in a pump having a casing and an impeller rotating inside the casing, and the casing and the blades of the impeller are provided. A foreign matter removing mechanism for removing foreign matter existing in the gap, which is an opening provided so as to communicate the inside and the outside of the casing, and faces the blade through the opening, and the casing and the said. A discharge mechanism for discharging foreign matter existing in the gap between the blades from the inside to the outside of the casing through the opening, and a discharge mechanism outside the casing so as to cover the opening while having the discharge mechanism inside. The point is that a storage unit for storing the foreign matter discharged by the discharge mechanism is provided.

In the pump, the impeller is rotated by the drive machine to give velocity energy to the sucked fluid, and the velocity energy is converted into pressure energy by the pump casing and discharged. Since the pressure fluid leaks to the outside of the casing, the pump efficiency is greatly reduced.

According to the above configuration, the foreign matter sucked into the pump can be discharged to the outside of the casing through the opening provided in the casing by the discharge mechanism while passing through the gap between the casing and the blades of the impeller. However, at that time, the storage portion is configured to cover the opening, and the pressure fluid does not leak to the outside from the storage portion, so that a large decrease in pump efficiency can be prevented. The discharged foreign matter can be stored in the storage unit and discarded when the pump is inspected. It is preferable that the storage portion is provided with an inspection lid.

The pump may be a vertical shaft pump or a horizontal shaft pump, and the impeller may be a mixed flow impeller, an axial flow impeller, or a spiral impeller.

In the present invention, the discharge mechanism rotates with a drive roller that rotates by obtaining power from the rotating impeller and the drive roller in the opposite direction, and cooperates with the drive roller to sandwich the foreign matter. It is preferable to include a driven roller for discharging and a transmission mechanism for transmitting the power of the driving roller to the driven roller.

According to the above configuration, since the drive roller and the driven roller are driven by obtaining power from the impeller, it is not necessary to separately prepare the power for driving the discharge mechanism.

In the present invention, it is preferable that the drive roller is configured to obtain the power of the impeller by direct contact with the blade.

According to the above configuration, the rotation of the impeller can be transmitted to the drive roller by a simple configuration of direct contact between the impeller and the drive roller.

In the present invention, the discharge mechanism has a drive roller that rotates by receiving power from the outside of the pump and a drive roller that rotates in a direction opposite to the drive roller and cooperates with the drive roller to sandwich and discharge the foreign matter. It is preferable that the driven roller is provided with a transmission mechanism for transmitting the power of the driving roller to the driven roller.

According to the above configuration, since the drive roller and the driven roller are driven by receiving power from the outside of the pump, the discharge mechanism can be driven independently without depending on the rotation of the impeller.

In the present invention, it is preferable that the drive roller and the driven roller are provided so that their rotation axes intersect with respect to the passing direction of the blades, and at that time, the drive roller is provided. It is particularly preferable that the driven rollers are provided so that their rotation axes are along a direction orthogonal to the passing direction of the blades.

As a result of diligent research by the inventors, it was found that, according to the above configuration, foreign matter can be discharged smoothly. Further, according to the above configuration, the drive roller can be rotated by obtaining power from the impeller that rotates.

In the present invention, it is preferable that the driving roller and the driven roller are provided over the passing width of the blades.

According to the above configuration, the foreign matter can be discharged by the driving roller and the driven roller regardless of the position of the foreign matter on the blade.

A feature of the pump according to the present invention for achieving the above-mentioned object is that a foreign matter removing mechanism having any of the above-mentioned feature configurations is provided.

According to the above-described configuration, it is possible to provide a pump having a simple configuration and having a foreign matter removing mechanism having a small effect on the pump efficiency.

It is explanatory drawing of the vertical shaft mixed flow pump. It is explanatory drawing of the foreign matter removal mechanism. It is explanatory drawing of the foreign matter removal mechanism. It is explanatory drawing of the foreign matter removal mechanism. It is explanatory drawing of the foreign matter removal mechanism which concerns on another Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 1, as an example of the pump, in the vertical oblique flow pump 10 installed in a rainwater drainage pump station or the like, the fluid sucked from the suction bell 12 by the rotation of the impeller 11 is passed through the discharge bowl 13 on the downstream side. It is configured to be pumped to the pumping pipe 14.

The impeller 11 is provided at the tip of a rotating shaft 16 rotated by an electric motor 15, and is configured to rotate inside a casing 17 provided between a suction bell 12 and a discharge bowl 13. The casing 17 is made of a material having strength and corrosion resistance against a fluid, such as stainless steel and gray cast iron.

The impeller 11 includes a blade boss 18 supported by a rotating shaft 16 and a plurality of blades 19 provided on the blade boss 18. The blade boss 18 and the blade 19 are formed of a material having strength and corrosion resistance against a fluid, such as stainless steel and gray cast iron. The impeller 11 rotates with a slight gap between the blade 19 and the casing 17.

Foreign matter contained in the fluid sucked from the suction bell 12 may be entangled in this gap. In order to remove the foreign matter, the vertical oblique flow pump 10 is provided with a foreign matter removing mechanism 20.

As shown in FIGS. 2 to 4, the foreign matter removing mechanism 20 includes an opening 21, a discharge mechanism 22, and a storage portion 23.

The opening 21 is provided so as to communicate the inside and the outside of the casing 17.

The discharge mechanism 22 includes a drive roller 24, a driven roller 25, and a transmission mechanism 26.

The drive roller 24 and the driven roller 25 are cylindrical bodies whose peripheral surfaces are at least made of a material softer than the blades 19, such as resin and rubber, and the drive roller 24 and the driven roller 25 are the peripheral surfaces of the drive roller 24. It is pivotally supported by the bearing 27 with a slight gap between the peripheral surface of the driven roller 25 and a foreign object.

At that time, the drive roller 24 and the driven roller 25 extend over the passing width of the blade 19 of the impeller 11 in a direction intersecting the passing direction of the blade 19 of the impeller 11, particularly in a direction orthogonal to the passing direction. It is provided along.

The drive roller 24 and the driven roller 25 may have the same diameter, or for example, the diameter of the drive roller 24 may be larger than the diameter of the driven roller.

The rotation of the drive roller 24 is configured to be transmittable to the driven roller 25 by a transmission mechanism 26 that transmits power from the rotation shaft of the drive roller 24 to the rotation shaft of the driven roller 25. The transmission mechanism 26 includes a plurality of gears, and is configured so that the drive roller 24 and the driven roller 25 can rotate in opposite directions to each other.

The drive roller 24 is arranged at a position where it can come into direct contact with the blade 19 of the rotating impeller 11, and rotates by receiving power from the impeller 11. The rotation of the drive roller 24 is transmitted to the driven roller 25 via the transmission mechanism 26.

As described above, the drive roller 24 and the driven roller 25 rotate in opposite directions, so that the drive roller 24 and the driven roller 25 cooperate with each other and exist in the gap between the casing 17 and the blade 19 of the impeller 11. Foreign matter can be sandwiched and discharged from the inside to the outside of the casing 17 through the opening 21.

The storage portion 23 is composed of a box-shaped body, and is arranged so as to cover the opening 21 in a closed manner while incorporating the discharge mechanism 22 inside the casing 17.

The storage unit 23 is provided with an inspection lid 28. The foreign matter discharged by the discharge mechanism 22 stored in the storage unit 23 can be discarded through the inspection lid 28 when the vertical oblique flow pump 10 is pulled up to the ground by periodic maintenance or the like.

In the above-described embodiment, the case where the drive roller 24 and the driven roller 25 are provided over the passing width of the blade 19 of the impeller 11 has been described, but the drive roller 24 and the driven roller 25 are the impeller 11 Of the passing width of the blade 19, for example, only the position near the front edge of the blade 19 or only the position near the rear edge of the blade 19 may be provided.

In the above-described embodiment, the case where the drive roller 24 and the driven roller 25 are provided along the direction orthogonal to the passing direction of the blade 19 of the impeller 11 has been described, but the opening 21 is shown in FIG. As shown in 5, the direction may be provided so as not to be orthogonal to the passing direction of the blade 19 of the impeller 11, and may be provided along the direction intersecting the inclination of the blade 19. Further, the rotation axes of the drive roller 24 and the driven roller 25 may be arranged so as to match the inclination of the blade 19.

In the above-described embodiment, the configuration in which the drive roller 24 and the driven roller 25 are arranged so that the peripheral surface of the drive roller 24 and the peripheral surface of the driven roller 25 have a slight gap in which foreign matter can be sandwiched is described. However, the drive roller 24 and the driven roller 25 may be arranged in a state where the peripheral surface of the drive roller 24 and the peripheral surface of the driven roller 25 are in contact with each other as long as at least one of them can be elastically deformed.

In the above-described embodiment, the case where the peripheral surface of the drive roller 24 and the peripheral surface of the driven roller 25 are smoothly configured has been described, but at least one of the peripheral surfaces of the drive roller 24 or the driven roller 25 is plural. Protrusions may be provided. At that time, the protrusion may be configured to come into contact with the other peripheral surface. Further, the peripheral surface of the drive roller 24 and the peripheral surface of the driven roller 25 may be configured to generate a positive water flow in the sandwiching direction and guide foreign matter between them.

In the above-described embodiment, the configuration in which the transmission mechanism 26 is configured to transmit the rotation of the drive roller 24 to the driven roller 25 by a plurality of gears has been described, but the transmission mechanism 26 is provided on the rotation shaft of the drive roller 24. It may be composed of a provided pulley, a pulley provided on the rotating shaft of the driven roller 25, and a pulley belt hooked on the pulley. Further, the transmission mechanism 26 may be configured so that the rotation of the drive roller 24 can be transmitted to the driven roller 25 by such that the peripheral surface of the drive roller 24 and the peripheral surface of the driven roller 25 come into contact with each other.

In the above-described embodiment, the drive roller 24 is arranged at a position where it can directly contact the blade 19 of the rotating impeller 11, and is configured to rotate by receiving power from the impeller 11. Although the case has been described, the drive roller 24 may be configured to rotate by receiving power from the outside of the vertical oblique flow pump 10.

In the above-described embodiment, the case where the pump is an axial mixed flow pump has been described, but the pump may be a horizontal axis pump, and the impeller is an axial flow impeller or a swirl impeller. May be good.

At that time, the drive roller 24 is not limited to a configuration in which the drive roller 24 is arranged at a position where it can directly contact the blade 19 of the rotating impeller 11 and rotates by receiving power from the impeller 11, for example, the blade. When the vehicle is a spiral impeller, the drive roller 24 rotates by obtaining power from the impeller 11 by coming into contact with the blade boss 18 of the rotating impeller 11 or the shroud included in the spiral impeller. It may be configured in. In this case, the drive roller 24 does not have to be in contact with the blade 19.

Each of the above-described embodiments is an example of the present invention, and the description does not limit the present invention, and the specific configuration of each part can be appropriately modified and designed within the range in which the effects of the present invention are exhibited. ..

10: Vertical shaft mixed flow pump 11: Impeller 12: Suction bell 13: Discharge bowl 14: Pumping pipe 15: Motor 16: Rotating shaft 17: Casing 18: Blade boss 19: Blade 20: Foreign matter removal mechanism 21: Opening 22: Discharge mechanism 23: Storage unit 24: Drive roller 25: Driven roller 26: Transmission mechanism 27: Bearing 28: Inspection lid

Claims (8)

A foreign matter removing mechanism provided in a pump having a casing and an impeller rotating inside the casing to remove foreign matter existing in a gap between the casing and the blades of the impeller.
An opening provided so as to communicate the inside and the outside of the casing,
A discharge mechanism that faces the blades through the opening and discharges foreign matter existing in the gap between the casing and the blades from the inside to the outside of the casing through the opening.
A foreign matter removing mechanism provided on the outside of the casing so as to cover the opening while having the discharge mechanism inside, and a storage portion for storing foreign matter discharged by the discharge mechanism. The discharge mechanism includes a drive roller that rotates by receiving power from the rotating impeller, and a driven roller that rotates in the direction opposite to the drive roller and cooperates with the drive roller to pinch and discharge the foreign matter. The foreign matter removing mechanism according to claim 1, further comprising a transmission mechanism for transmitting the power of the drive roller to the driven roller. The foreign matter removing mechanism according to claim 2, wherein the drive roller is configured to obtain power of the impeller by direct contact with the blade. The discharge mechanism includes a drive roller that rotates by receiving power from the outside of the pump, and a driven roller that rotates in the direction opposite to the drive roller and cooperates with the drive roller to pinch and discharge the foreign matter. The foreign matter removing mechanism according to claim 1, further comprising a transmission mechanism for transmitting the power of the drive roller to the driven roller. The foreign matter removing mechanism according to any one of claims 2 to 4, wherein the driving roller and the driven roller are provided so that their rotation axes intersect with respect to the passing direction of the blades. .. The foreign matter removing mechanism according to claim 5, wherein the driving roller and the driven roller are provided so that their rotation axes are along a direction orthogonal to the passing direction of the blades. The foreign matter removing mechanism according to any one of claims 2 to 6, wherein the driving roller and the driven roller are provided over the passing width of the blades. A pump provided with the foreign matter removing mechanism according to any one of claims 1 to 7.

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