JP2011236829A - Agitating body for submerged pump and submerged pump using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agitating body for a submerged pump, and the submerged pump having the agitating body capable of efficiently floating and sucking up a water bottom sediment by smaller power.SOLUTION: The agitating body includes a base 36 having an inverse frusto-right circular conical shape, a plurality of spiral blades 37 arranged at predetermined circumferential intervals outside the base 36, and a boss 38 coaxially formed at the base end side of the base 36. An angle θ formed of a meridian plane shape of the spiral blades 37 is set to 30-48 degrees, and preferably, to 35-45 degrees.

Description

The present invention stirs and floats sediment at the bottom of a dredging site, civil engineering site, sewage treatment plant, factory drainage basin, etc., then sucks it while diluting it with the surrounding water and discharges it to a desired location. The present invention relates to a submersible pump agitator that is attached to a submersible pump used for the purpose, and a submersible pump using the same.

Patent Document 1 proposes a submersible pump provided with a stirrer for the purpose described above. A typical example is shown in FIG. 6. This submersible pump 80 has a suction opening 81 formed at the center of the lower surface and a discharge opening 82 formed at a part of the outer peripheral wall, and is rotated by a motor 83 inside. An impeller casing 86 including an impeller 85 fixed to the shaft 84; a cylindrical strainer 88 having an upper portion connected to the lower end of the impeller casing 86 and a plurality of suction flow openings 87; and an impeller casing 86 and a stirrer 89 fixed to the lower part of the rotating shaft 84 disposed through the strainer 88.

With the above-described configuration, the rotating shaft 84 is rotated together with the driving of the motor 83 so that the impeller 85 and the stirring body 89 rotate integrally, and the stirring water flow is generated by the rotation of the stirring body 89. The object floats and is sucked into the strainer 88 through the suction flow opening 87, and then the bottom sediment is discharged from the discharge opening 82 through the impeller casing 86.

Japanese Patent Laid-Open No. 10-9182

However, in the stirring body disclosed in Patent Document 1, as a result of causing the bottom sediment to diverge more than necessary, or as a result of insufficient floating of the sediment, the suction rate of the sediment is reduced. In addition, the energy consumed for the agitation has become larger than necessary, leading to an increase in energy costs and increasing the size of the motor and the pump.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a submerged pump agitator and a submersible pump using the submerged pump capable of efficiently levitating and sucking up a bottom sediment with less power. To do.

The submerged pump agitator according to the first aspect of the present invention, comprising: a trunk portion having a reverse truncated right cone shape; and a plurality of spiral blades provided with a predetermined circumferential interval outside the trunk portion; And a boss portion formed coaxially on the proximal end side of the trunk portion, and the angle formed by the meridional shape of the spiral blade is 30 to 48 degrees.
Here, the meridional shape is a shape formed by overlapping arbitrary cross sections (that is, meridian surfaces) passing through the axis (rotation center) of the spiral blade, or a shape of a rotation locus when the rotation axis is viewed from a right angle direction. The angle formed by the meridional surface shape coincides with the angle formed by the two side lines of the rotating body that rotates the spiral blade.

In the submerged pump stirring body according to the first invention, it is more preferable that the angle formed by the meridional shape of the spiral blade is in the range of 35 to 45 degrees.
Further, in the submersible pump stirring body according to the first invention, it is more preferable that the adjacent spiral blades have a gap in the circumferential direction when viewed in the axial direction.
In the submerged pump agitator according to the first aspect of the present invention, the spiral blade may have a constant thickness at the radial end.

The submersible pump according to the second invention includes the submerged pump stirring body according to the first invention in the lower part.

The submerged pump agitator according to the first invention and the submersible pump according to the second invention using the submerged pump have an angle formed by the meridional surface shape of the spiral blades of 30 to 48 degrees. Can be levitated and sucked up efficiently.

It is a front sectional view of the submersible pump which comprises the stirring body for submersible pumps concerning one embodiment of the present invention. It is a perspective view of the stirring body for the submersible pump. It is a top view of the stirring body for the submersible pump. It is a bottom view of the stirring body for the submersible pump. It is a front view of the stirring body for submersible pumps which also shows the meridional shape of a spiral blade. It is a front sectional view of a submersible pump according to a conventional example.

Hereinafter, with reference to the accompanying drawings, a submersible pump stirring body and a submersible pump using the same according to an embodiment of the present invention will be described.
As shown in FIG. 1, a submersible pump 10 according to an embodiment of the present invention is a motor in which a main part is made of stainless steel or special steel which is hard to be corroded and has wear resistance, and a rotary shaft 11 is arranged vertically. Part 12, pump part 13 provided at the lower part of motor part 12, and stirring part 14 provided at the lower part of pump part 13. Hereinafter, these will be described in detail.

The motor unit 12 includes a stator 16 provided in a cylindrical intermediate housing 15, and a rotor 17 disposed with a gap inside the stator 16 and fixed to the rotary shaft 11. The upper housing 20 and the lower housing 21 are provided with bearing portions 18 and 19 that are flange-coupled on the upper and lower sides and support the upper and lower sides of the rotating shaft 11. A cable 23 connected to the stator 16 is drawn from the top of the upper hanging 20 via the seal mechanism 22, and a radial bearing 24 that rotatably supports the upper end of the rotating shaft 11 on the lower bearing portion 18 of the upper housing 20. Is provided. The lower housing 21 is provided with a radial bearing 26 and a thrust bearing 27 that rotatably support an intermediate portion of the rotating shaft 11.

The pump unit 13 is attached to the lower part of the lower housing 21, and includes an impeller casing 30 having a discharge opening 28 on one side and a suction opening 29 in the center of the lower part, and a center of the impeller casing 30. And a fixed impeller 31. An L-shaped tube 32 is flanged to the discharge opening 28. In FIG. 1, reference numeral 32 a denotes a mechanical seal that prevents water in the pump unit 13 from entering the lower housing 21.

The stirring unit 14 provided immediately below the pump unit 13 passes through the strainer 33, a bottomed cylindrical strainer 33 provided at the bottom of the impeller casing 30, a support member 34 fixed to the lower portion of the strainer 33, and the strainer 33. And an agitator (agitator for submersible pump) 35 fixed to the lower end of the rotating shaft 11. The strainer 33 has a large number of openings in the bottom and the peripheral wall, and has a structure in which water, sludge, and the like can be filtered and guided from the periphery and the bottom.

The stirrer 35 is made of stainless steel or hard special steel which is not easily corroded and has wear resistance, and has a reverse truncated cone shape (that is, a truncated cone shape) as shown in FIGS. The core portion 36, a plurality (preferably 2 to 4) of spiral blades 37 that are evenly arranged on the outside of the backbone portion 36, and the base side (that is, the upper side) of the backbone portion 36 are integrally aligned with each other. And a boss portion 38 that is formed as a result.

A female screw 39 is formed on the upper side of the boss portion 38, and a male screw 40 formed on the lower end portion of the rotating shaft 11 is screwed. Reference numeral 41 denotes a nut that is screwed into the female screw 40 and cooperates with the screw of the boss portion 38 to prevent loosening (that is, exhibits a double nut effect).
In this embodiment, as shown in FIG. 5, the width of each spiral blade 37 from the trunk portion 36, that is, the height in the normal direction with respect to the side surface of the trunk portion 36 is equal to H.

Accordingly, the angle θ (that is, the apex angle) formed by the meridional shape of the tip portion of the spiral blade 37 is equal to the opening angle φ formed by the meridional shape of the basic portion 36 and is in the range of 30 to 48 degrees. . Here, the angle θ formed by the meridional shape of the tip of the spiral blade 37 is the opening angle (vertical angle) of the truncated cone drawn by the spiral blade 37 when the stirring body 35 is rotated about the axis. It is.

Thus, by setting the angle θ formed by the meridional surface shape of the spiral blade 37 to 30 to 48 degrees, the bottom sediment can be efficiently lifted and sucked up with minimum power. When the angle formed by the meridional shape of the spiral blade 37 is less than 30 degrees, the lateral swirling flow becomes excessively strong, and as a result, the sediment diverges to the surroundings and the sucking and collecting rate is lowered.

On the contrary, when the angle θ formed by the meridional surface shape of the spiral blade 37 is larger than 48 degrees, the stirring water flow becomes excessively downward, resulting in insufficient levitation of the precipitate and a reduction in the suction recovery rate. . Further, when the outer diameter of the spiral blade 37 is increased while the angle θ formed by the meridional surface shape of the spiral blade 37 is larger than 48 degrees, the power increases and it becomes uneconomical.
More preferably, the angle θ formed by the meridional surface shape of the spiral blade 37 is 35 to 45 degrees (more preferably 35 to 42 degrees). As a result, the bottom sediment can be efficiently levitated and sucked up with less power.

In FIG. 5, D represents the diameter of the upper circle of the trunk portion 36, for example, in the range of 0.2 to 0.3 times the outer diameter of the impeller 31, and h represents the height of the trunk portion 36. In the range of 1.2 to 2 times the height of the impeller 31. By forming in this way, the balance of the energy used for the stirring body 35 and the impeller 31 is maintained.

In this embodiment, the number of the spiral blades 37 is 3, the blade angle α of the spiral blades 37 when the stirring body 35 is viewed in the axial direction is 60 to 90 degrees, and the gap angle between the adjacent spiral blades 37 β is 30 to 60 degrees, and has a gap space 43 where the spiral blade 37 is not in the circumferential direction when viewed in the axial direction. As a result, the spiral blade 37 pushes down the liquid material sucked from the gap space 43 and part of the liquid material efficiently escapes to the side. The number n of the spiral blades 37 is preferably about 2 to 4, but the gap angle β between the adjacent spiral blades 37 is preferably provided in the range of (90 / n to 180 / n) degrees, for example.

The spiral blade 37 faces downward and has a smaller radial width, but its lower end is on the same plane as the lower end surface of the inverted truncated conical main part 36. Further, the radially outer end 44 of the spiral blade 37 has, for example, a width of 0.25 to 0.4 times the diameter d of the lower end of the trunk portion 36, and does not easily wear even when used for a long time. It has become.

The present invention is not limited to the above-described embodiment, and the present invention can be applied even if the dimensions are changed and the shape of the spiral blade is changed without changing the gist of the present invention.

10: submersible pump, 11: rotating shaft, 12: motor unit, 13: pump unit, 14: stirring unit, 15: intermediate housing, 16: stator, 17: rotor, 18, 19: bearing unit, 20: upper housing, 21: Lower housing, 22: Sealing mechanism, 23: Cable, 24, 26: Radial bearing, 27: Thrust bearing, 28: Discharge opening, 29: Suction opening, 30: Impeller casing, 31: Impeller, 32: L-shaped tube 32a: mechanical seal, 33: strainer, 34: support member, 35: stirrer, 36: backbone, 37: spiral blade, 38: boss, 39: female screw, 40: male screw, 41: nut, 43: gap Space, 44: radially outer edge

Claims (5)

A backbone portion having a reverse truncated right cone shape, a plurality of spiral blades provided on the outside of the backbone portion with a predetermined circumferential interval, and a boss portion formed coaxially on the proximal end side of the backbone portion And an angle formed by the meridional shape of the spiral blade is 30 to 48 degrees. 2. The submerged pump agitator according to claim 1, wherein an angle formed by the meridional shape of the spiral blade is in a range of 35 to 45 degrees. The submerged pump agitator according to claim 1 or 2, wherein the adjacent spiral blades have a gap in the circumferential direction when viewed in the axial direction. The submerged pump agitator according to any one of claims 1 to 3, wherein the spiral blade has a constant thickness even at a radial end. The submersible pump which equips the lower part with the stirring body for submersible pumps of any one of Claims 1-4.

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