JPH10184581A - Pump casing for submerged pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent bending and rupture of a tip part of a draining part of a casing body formed of hard rubber. SOLUTION: A pump casing 30 of a submerged pump is composed of a cylindrical casing body formed of hard rubber and opened at its upper face, and an upper face cover 34 for covering the upper face. When an impeller 36 is rotated, a fluid flows into a pump chamber 31a in the casing body and becomes vortex flow. Part of the fluid in the pump chamber 31a is made flow out to a discharge chamber 31c by a draining part protruded toward the upstream of vortex flow between the pump chamber 31a and the discharge chamber 31c. Three protruding parts 31f are provided at the upper face of the draining part, and each protruding part 31f is fitted into each recessed part 34f of the upper face cover 34. The draining part is prevented from bending by fitting of each protruding part 31f and each recessed part 34f.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for drainage of stored water and spring water at construction sites such as civil engineering and buildings, or for simply supplying and discharging agricultural water and domestic water. Regarding the pump casing of the submersible pump, in particular, the casing body in which the impeller is housed is made of hard rubber,
The present invention relates to a pump casing made of an elastic body such as a soft synthetic resin.

[0002]

2. Description of the Related Art In a construction site, a submersible pump used for draining stored water or the like generally uses an impeller disposed in a pump chamber in a pump casing by a motor disposed above the pump casing. By rotating, the fluid is sucked into the pump chamber, and the sucked fluid is swirled in the pump chamber by the centrifugal force of the impeller, and a part of the swirl flows into the discharge chamber communicating with the pump chamber. I have.

Conventionally, the casing of a submersible pump is made of cast iron. However, the casing is heavy and inconvenient to carry. Moreover, if water containing sand or the like is sucked into the pump casing, the casing will be severely worn, and long-term use will occur. There is a problem that it cannot be used stably over a long period of time. For this reason, recently, in order to reduce the weight of the submersible pump and to be able to use it stably for a long period of time, the pump casing and the impeller are made of hard rubber and soft synthetic resin which are lightweight and have excellent wear resistance. Submersible pumps manufactured using such elastic bodies have been developed.

[0004] As described above, when the pump casing is made of hard rubber, since the die cannot be cut out using a core like a casting, a cylindrical casing body having an open upper and lower surfaces, 2. Description of the Related Art A pump casing is constituted by a hard rubber upper cover that covers an open upper surface of a casing body.

[0005] A pump chamber accommodating the impeller and a discharge chamber in communication with the pump chamber are formed inside the casing body, and a pump chamber and the discharge chamber are provided between the pump chamber and the discharge chamber.
A drain is provided for returning a part of the vortex formed in the pump chamber to the pump chamber. This draining portion projects from the inner peripheral surface of the casing body toward the upstream side of the vortex in the pump chamber.

As described above, the pump casing and the top cover made of elastic hard rubber are light in weight and excellent in abrasion resistance, so that their durability is remarkably improved, and they are stable over a long period of time. Can be used.

However, in the pump casing having such a configuration, since the entire casing body is integrally formed of the hard rubber, the drain portion is also formed of the hard rubber which is an elastic body. In addition, since the drain portion of the casing body projects from the inner peripheral surface of the casing body toward the upstream side of the vortex in the pump chamber, there is a problem that the tip portion is easily bent along the vortex. is there. In particular, while the fluid flowing into the discharge chamber along the drainage section is in a high pressure state, the vortex flowing in the pump chamber along the drainage section is in a low pressure state, and the tip of the drainage section is in the pump chamber. Is easy to bend along the eddy current. If the tip of the drainer repeatedly bends or bends over a long period of time, it may bend or break. Also, the tip of the bent drainer may come into contact with the rotating impeller and hinder the rotation of the impeller.

In order to solve such a problem, Japanese Utility Model Publication No. 1-392020 and Japanese Utility Model Publication No. 2-36960 disclose embedding a reinforcing material such as a metal in a drain portion, and partially cover a top cover. By inserting in
A configuration for preventing the draining portion from bending is disclosed.

In Japanese Utility Model Laid-Open Publication No. 3-87996,
A configuration is disclosed in which the top cover is pressed against a drain section provided in the casing body to prevent the drain section from bending.

[0010]

Problems to be Solved by the Invention
In the configuration disclosed in Japanese Patent Application Laid-Open Publication No. Hei. 2-36960 and Japanese Utility Model Publication No. 2-36960, when the reinforcing material is embedded in the drain portion of the casing main body, when the casing main body is manufactured by an elastic body such as hard rubber, the reinforcing body is reinforced. There is a problem that the material must be buried and its manufacture is not easy.

Further, as disclosed in Japanese Utility Model Laid-Open Publication No. 3-87996, in the configuration in which the drainage portion of the casing body is pressed by the top cover to prevent the drainage portion from bending, the deflection of the drainage portion is sufficiently suppressed. Can not do it.

An object of the present invention is to solve such a problem, and an object of the present invention is to suppress bending of a drain portion of a casing body formed of an elastic body and to make sure that the drain portion is bent or broken. Can be prevented,
Moreover, it is an object of the present invention to provide a pump casing of a submersible pump which is easy to manufacture.

[0013]

A pump casing of a submersible pump according to the present invention is formed in a cylindrical shape whose upper surface is opened by an elastic body, and a pump in which an impeller rotatably driven by a motor is housed. Between the chamber, a discharge chamber communicated with the pump chamber so that the vortex generated by the rotation of the impeller flows, and between the pump chamber and the discharge chamber so that a part of the vortex in the pump chamber flows to the discharge chamber. A casing main body having a drain portion protruding toward the upstream side of the vortex, and an upper cover made of an elastic material covering an open upper surface of the casing main body, wherein either the upper surface of the drain portion or the lower surface of the upper cover is provided. It is characterized in that the convex portion provided on one side is fitted into the concave portion provided on the other side.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing an example of an embodiment of a submersible pump having a pump casing of the present invention. This submersible pump has a motor 20 and a pump casing 30 mounted below the motor 20.

The motor 20 includes a cylindrical stator casing 24, a rotor shaft 21 vertically inserted through the axial center of the stator casing 24, and a rotor 22 integrally fitted to the outside of the rotor shaft 21. And a stator 23 attached to an inner peripheral surface of a stator casing 24 so as to surround the rotor 22.
And The stator casing 24 is integrally provided with an outflow passage 24c extending along the vertical direction. A discharge port 24d is provided at the upper end of the outflow path 24c.

The upper end of the rotor shaft 21 disposed at the axis of the motor 20 is rotatably supported by a bearing 26. The lower portion of the rotor shaft 21 is rotatably supported by a bearing 29 provided on the bottom surface 24a of the stator casing 24.
The lower end of the rotor shaft 21 extends downward through the bottom surface 24 a of the stator casing 24.

The bottom portion 24a of the stator casing 24
The lower end of the rotor shaft 21 extending from the shaft extends through the seal bracket 28 attached to the lower side of the stator casing 24 and enters the inside of the pump casing 30. The seal bracket 28 is made of aluminum, and has a cylindrical boss 28a projecting downward at the center thereof. The seal bracket 28 is provided on the bottom surface 24 of the stator casing 24.
a is disposed at an appropriate interval from the mechanical seal 2, and the rotor shaft 21 passing between them is
The shaft is sealed by 7. The rotor shaft 21
The seal bracket 28 penetrates through the boss 28 a and enters the inside of the pump casing 30. The rotor shaft 21 through which the seal bracket 28 is inserted is sealed by an oil seal 28b provided in a boss 28a of the seal bracket 28.

The pump casing 30 has a casing main body 31 formed of a hard rubber into a cylindrical shape having an open upper surface, and a disk-shaped upper cover 34 for covering the open upper surface of the casing main body 31. The internal space is a pump chamber 31a. The rotor shaft 2 that has entered the pump chamber 31a of the casing body 31
An impeller 36 is attached to the lower end of 1.

FIG. 2A is a bottom view of the top cover 34,
FIG. 2B is a cross-sectional view taken along line AA of FIG. A through hole 34a is provided in the center of the top cover 34, and the boss 28a of the seal bracket 28 fits into the through hole 34a, and the seal bracket 28
Is pressed into contact with the lower surface. The upper cover 34 is provided with a discharge portion 34b that protrudes upward in a cylindrical shape, facing the outflow passage 24c provided inside the motor 20.
As shown in FIG. 1, the discharge portion 34b is fitted into a cylindrical portion 28c which is provided on the seal bracket 28 and protrudes upward so as to face the outflow passage 24c of the motor 20.

As shown in FIG. 2, the top cover 34 has
6 penetrating vertically so as to surround the through hole 34a
Three pressure balance holes 34d are provided. Each of the three pressure balance holes 34d is a through hole 34a.
Are provided at equal intervals in the circumferential direction on concentric circles having different diameters, and are provided in the middle of three pressure balance holes 34d provided on one concentric circle and three concentric circles provided on the other concentric circle. The pressure balance holes 34d are respectively located. In the peripheral portion of the top cover 34, four bolt insertion holes 34e are provided at equal intervals in the circumferential direction.
Is provided.

FIG. 3 is a plan view of the casing body 31 of the pump casing 30. A suction port 31b is provided at the center of the bottom surface of the casing body 31. The suction port 31b communicates with a pump chamber 31a in the casing body 31. The impeller 36 disposed in the pump chamber 31a is configured to rotate in a predetermined direction, and the rotation of the impeller 36 sucks fluid into the pump chamber 31a through the suction port 31b. Pump room 31
The fluid sucked into a is caused by the rotation of the impeller 36.
A vortex flows in the direction indicated by arrow B in FIG.

Inside the casing body 31, there is provided a discharge chamber 31c which is in communication with the pump chamber 31a. The discharge chamber 31c extends in the tangential direction of the pump chamber 31a so that a part of the fluid that has been swirled in the pump chamber 31a flows in. The distal end portion of the discharge chamber 31c is an outer peripheral edge of the pump chamber 31a. It has an arc shape along with. Discharge chamber 3
The upper surface of 1c is open upward throughout.
Discharge part 34b whose tip is provided on top cover 34
To be opposed.

Between the discharge chamber 31c and the pump chamber 31a,
The casing body 31 is partitioned by a drainer 31d vertically raised from the bottom surface. Drainer 31d
Are projected from the peripheral wall surface of the casing body 31 along the inner peripheral surface of the pump chamber 31a.
The leading end of 1d is tapered such that the width direction dimension is gradually reduced toward the leading end.

Four bolt insertion holes 31e are vertically provided on the peripheral wall surface of the casing body 31 at equal intervals in the circumferential direction. Each bolt insertion hole 31e
The bolts 33 (see FIG. 1) inserted from the lower side of the casing main body 31 are inserted through the casing main body 3.
1 each bolt insertion hole 34e of the upper surface cover 34 covering the upper surface
Is inserted inside. Each bolt 33 is screw-coupled to each screw groove 28e (see FIG. 1) provided in the seal bracket 21.

On the upper surface of the drainer 31d provided on the casing body 31, three projections 31f are provided. The convex portions 31f are arranged side by side at equal intervals from the peripheral surface of the pump chamber 31a along the direction in which the draining portion 31d protrudes, and each protrudes upward in a columnar shape. Also, as shown in FIGS. 1 and 2,
A state in which three cylindrical concave portions 34f are opened on the lower surface of the upper cover 34 so that the respective convex portions 31f provided on the drainer 31d are fitted into a portion of the upper cover 34 facing the drainer 31d. It is provided in.

The pump casing 30 includes the strainer 4
Covered by 0. The strainer 40 is attached to the casing main body 31 by four bolts 33 that attach the casing main body 31 to the seal bracket 28 together with the upper surface cover 34.

In the submersible pump having such a configuration, when the rotor 20 is rotated by the driving of the motor 20, the impeller 36 disposed in the pump chamber 31a of the pump casing 30 is rotated, and the impeller 36 is provided on the casing body 31. The fluid flows into the pump chamber 31a through the suction port 31b. The fluid that has flowed into the pump chamber 31a flows in the pump chamber 31a in the direction indicated by the arrow B in FIG. 3 to form a vortex, is branched by the draining section 31d, and partially flows into the discharge chamber 31c. . Then, the top cover 34
Through the discharge portion 31b provided in the motor 20, flows into an outflow passage 24c provided in the motor 20, and is discharged from the outflow passage 24c through a discharge port 24d provided on the upper surface of the motor 20.

At this time, the pump chamber 31a is moved from the discharge chamber 31
Since the pressure of the fluid flowing inside the pump chamber 31a along the drainage portion 31d of the casing body 31 made of hard rubber becomes lower than the pressure of the fluid flowing into the inside c, the drainage portion 31d has a low pressure. Pump chamber 31a
Try to bend in. However, on the upper surface of the draining portion 31d, three convex portions 31f are provided side by side along the draining portion 31d, and each convex portion 31f is provided in each concave portion 34f of the upper surface cover 34 covering the upper surface of the casing body 31. Since they are fitted into each other, the water draining part 31d projecting into the pump chamber 31a is held by the top cover 34, and the water draining part 31d is prevented from being bent into the pump chamber 31a.

The pump chamber 31 of the casing body 31
a, the inside of the casing main body 3 has a low pressure.
The upper surface cover 34 that covers the open upper surface of the upper surface cover 1 is sucked into the pump chamber 31a, and the pressure balance holes 34d provided in the upper surface cover 34 allow the upper surface cover 34 to be connected to the lower surface facing the pump chamber 31a. The upper surface has the same pressure, and the upper surface cover 34 is prevented from being bent by being sucked into the pump chamber 31.

The protrusion 31f provided on the upper surface of the draining part 31d of the casing body 31 is
It is not necessary to be divided into three along the protruding direction of d, and as shown in FIG. 4, it may be a shape that is long and continuous along the protruding direction of the drainer 31d. In this case, the concave portion 34f of the upper surface cover 34 provided so as to fit the convex portion 31f is also provided with the convex portion 3f as shown in FIG.
In accordance with 1f, the shape is long and continuous along the projecting direction of the drainer 31d.

[0031]

As described above, the pump casing of the submersible pump according to the present invention is provided with a convex portion on one of the upper surface of the draining portion of the casing body formed of the elastic body and the lower surface of the upper cover, and the other portion has the convex portion. Since the concave portion into which the convex portion is fitted is provided, there is no possibility that the tip of the water drain portion is bent by the vortex in the pump chamber, and therefore, there is no possibility that the tip of the water drain portion is bent or broken.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of an embodiment of a submersible pump provided with a pump casing of the present invention.

FIG. 2A is a bottom view of a top cover used for a pump casing of the submersible pump, and FIG.
It is sectional drawing in the AA of (a).

FIG. 3 is a plan view of a casing main body used in the submersible pump.

FIG. 4 is a plan view of a casing main body used in another example of the embodiment of the pump casing of the submersible pump of the present invention.

FIG. 5 is a bottom view of an upper cover used for the pump casing.

[Explanation of symbols]

 Reference Signs List 20 Motor 21 Rotor shaft 22 Rotor 23 Stator 24 Stator casing 28 Seal bracket 30 Pump casing 31 Casing body 31a Pump chamber 31b Suction port 31c Discharge chamber 31d Drain section 31f Convex section 34 Top cover 34d Pressure balance hole 34f recess 36 Impeller

Claims (1)

[Claims] 1. A pump chamber in which an upper surface is opened by an elastic body and in which an impeller rotatably driven by a motor is accommodated therein, and a vortex generated by rotation of the impeller flows. And a drain portion projecting toward the upstream side of the vortex between the pump chamber and the discharge chamber so that a part of the vortex in the pump chamber flows to the discharge chamber. A casing main body, comprising an upper cover made of an elastic material that covers an open upper surface of the casing main body, and a convex portion provided on one of an upper surface of the drainer and a lower surface of the upper cover is provided on the other. A pump casing for a submersible pump, wherein the pump casing is fitted in a recessed portion.