JPH1175345A - Submergible pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a submergible pump with a prolonged service life or reduced size, by forming a passage of a circulating air flow in a motor section through a rotor fin, and thereby improving effect of cooling the stator winding and an upper bearing. SOLUTION: A motor section 2 is integrated with a pump section 3. The motor section 2 comprises a motor chamber 8 for housing a rotor 5 and a stator 7; a motor upper chamber 13 covered with a motor cover 15, located above the motor chamber; and a bracket 16 which defines the motor chamber 8 and the motor upper chamber 13, and holds an upper bearing 17. A rotor fin 21 for stirring air is installed at the end of the rotor 5 on the motor upper chamber 13 side to form a submergible pump. In this submergible pump, a vent hole 16a and ventilating sections 16b, 16c, 1a are formed on the bracket 16 in a position on the larger diameter side than the position where it is opposed to the rotor fin 21 and in proximity to the upper bearing, respectively, so that the motor chamber 8 communicate with the motor upper chamber 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a submersible pump which is integrally provided with a motor section and a pump section and is used, for example, for construction drainage, and in particular, can effectively cool stator windings and upper bearings. The present invention relates to the structure of the motor section of the underwater motor.

[0002]

2. Description of the Related Art FIG. 2 shows a general structure of a conventional underwater motor. As shown in the figure, a motor unit 2 for driving a main shaft 1 and a pump unit 3 for pumping water by rotation of the main shaft 1
The pump unit 3 and the motor unit 2 are sealed with a mechanical seal 4 so that the pressure water of the pump unit 3 does not leak to the motor unit 2 side.

The motor section 2 is provided with a rotor 5 rotating integrally with the main shaft 1 and a stator 7 wound with a stator winding 6 housed in a motor chamber 8. In the upper part, there is an entrance for the underwater cable 10,
A motor upper chamber 13 for housing devices such as a protector (overheat protection device) 11 and a capacitor 12 for preventing burnout of the motor unit due to overcurrent, open-phase operation or the like is arranged. The motor chamber 8 and the motor upper chamber 13 are watertightly surrounded by a substantially cylindrical motor frame 14 opened upward and a motor cover 15 connected to the upper end of the motor frame 14, and a bracket 16. It is divided up and down by.

The main shaft 1 is connected to the bracket 1
6 is rotatably supported by an upper bearing 17 mounted on the lower surface of the motor frame 6 and a lower bearing 18 mounted on the inner peripheral surface of the motor frame 14. A handle 20 for movement is provided.

[0005] A rotor fin 21 for stirring air is fixed to the rotor 5 on the end ring of the rotor 5 on the side of the motor upper chamber 13, so that the stator winding 6 is rotated as the rotor 5 rotates. It is configured to send wind for cooling.

On the other hand, the pump section 3 is provided with a vortex impeller 25 connected to the tip of the spindle 1.
The impeller 25 is surrounded by a pump casing 26 having a discharge port 26a and a suction port 26b, and sucks spring water or the like at a construction site from below and discharges the water from the side. Here, a nipple 27 for connecting a discharge hose is connected to the discharge port 26a.

The blades of the impeller 25 and the pump casing 2
A wide gap, which is a feature of the vortex pump, is provided between the bottom surfaces of the vortex pumps 6 so that even relatively large foreign substances can be easily discharged. The pump casing 26 is provided with a pump stand 28 serving both as a strainer and a leg so that the pump becomes independent and foreign substances having a certain size or more are not sucked into the pump.

The mechanical seal 4 is disposed in a mechanical seal chamber 31 defined by an intermediate casing 30 connecting the motor frame 14 and the pump casing 26 and the motor frame 14. Oil for lubricating and cooling the sliding surface of the mechanical seal is sealed. In order to extend the life of the mechanical seal 4, an oil seal is incorporated between the mechanical seal 4 and the impeller 25 to prevent foreign substances such as sand from approaching the mechanical seal sliding surface.

This submersible pump is used, for example, for draining spring water at a construction site. In general, a pump is installed at a place where spring water is generated, and is often used without a water level detector. . For this reason, when the pump is always in the operating state, the pump starts pumping when a certain amount of spring water (to the impeller position) accumulates, and when the pump reaches the pump suction limit water level, the operation of repeatedly entering the dry operation state is performed. There are many.

[0010]

However, in the above conventional example, since the motor chamber 8 of the motor section 2 and the motor upper chamber 13 are vertically separated from each other by the bracket 15, the motor fin 21 is Even if the air in the chamber 8 is agitated to cool the stator windings 6, the air is circulated only in the motor chamber 8, so that the cooling effect has a certain limit. For example, the upper bearing 17
Is located at the uppermost portion where the heated air in the motor chamber 8 gathers, so that the temperature rises remarkably, and there is a problem that grease may flow out and generate abnormal noise and vibration.

Further, since the motor section 2 is in a sealed state and is not water-cooled, the temperature of each section rises remarkably. Sometimes it was connected.

The present invention has been made in view of the above circumstances, and improves the cooling effect of a stator winding and an upper bearing by forming a circulation flow path of air in a motor unit by a rotor fin, thereby improving a long service life. It is an object of the present invention to provide a submersible pump capable of achieving downsizing or downsizing.

[0013]

The submersible pump of the present invention comprises:
A motor unit and a pump unit are integrally provided, and the motor unit divides a motor chamber accommodating a rotor and a stator, a motor upper chamber covered with a motor cover above the motor chamber, and a motor chamber and a motor upper chamber. In a submersible pump comprising a bracket for holding an upper bearing and having a rotor fin for air agitation at an end of the rotor on the side of the motor upper chamber, the motor chamber and the motor upper chamber communicate with the bracket. As described above, a ventilation hole is provided on a larger diameter side than a position facing the rotor fin, and a ventilation portion is provided near the upper bearing.

[0014] Further, a vent hole is provided in one or both portions located on the inner diameter side or the outer diameter side of the upper bearing, and an air flow path is formed between the motor chamber and the motor upper chamber. And

Further, the ventilation portion provided on the inner diameter side of the upper bearing is a ventilation hole provided on the main shaft.

Further, an axial distance between the rotor fin and the ventilation hole near the upper bearing is provided between the ventilation hole on the large diameter side and the ventilation part near the upper bearing, on the motor chamber side of the bracket for partitioning the motor chamber and the motor upper chamber. Is characterized in that a cylindrical projection is provided so as not to become large.

[0017] With this, as the rotor fins rotate, the air in the motor chamber enters the motor upper chamber from the ventilation holes provided in the bracket, and the air in the motor upper chamber enters the motor chamber from the ventilation section provided near the upper bearing. By circulating each, the stator winding and the upper bearing, which are heat generating sources, can be efficiently cooled.

In particular, by providing the ventilation portion on the inner diameter side or the outer diameter side of the upper bearing, the upper bearing can be effectively cooled by the circulating wind. Also, by providing the bracket with a projection, air flows into the motor upper chamber from the ventilation hole on the large diameter side of the bracket, and air returns to the motor chamber from the ventilation section near the upper bearing, thereby defining an air circulation path. Cooling efficiency can be increased.

Here, it is preferable that cooling fins are provided on the outer and inner walls of the motor cover, whereby the air in the upper chamber of the motor is cooled efficiently by the cooling fins having a large heat transfer area. Cooled air can flow into the motor chamber.

[0020]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. The same parts as those of the conventional example shown in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, a bracket 1 for partitioning a motor chamber 8 of a motor section 2 and a motor upper chamber 13 is provided.
A slightly thicker one is used as 6, and a ventilation passage as an air circulation path that connects the motor chamber 8 and the motor upper chamber 13 is provided at a position on the larger diameter side than the position where the bracket 16 faces the rotor fins 21. A hole 16a is provided.

Further, near the center of the bracket 16, a ventilation hole 16b for circulating the air in the motor upper chamber 13 to the motor chamber 8 is provided. A portion located on the outer diameter side of the upper bearing 17, that is, an inner peripheral surface of the cylindrical portion of the bracket 16, serves as a ventilation portion that connects the motor chamber 8 and the motor upper chamber 13 through the ventilation hole 16b. A ventilation slit 16c is provided. Furthermore, the upper bearing 1
7, on the outer peripheral surface of the spindle 1,
The motor chamber 8 and the motor upper chamber 1 are provided through the ventilation holes 16b.
3 are provided respectively as ventilation slits 1a as ventilation parts.

With the rotation of the rotor fins 21, the air in the motor chamber 8 is transferred from the ventilation holes (vents) 16 a provided in the bracket 16 to the motor upper chamber 13 through the rotation of the rotor fins 21. A circulation path of internal air for cooling the stator winding 6 and the upper bearing 17 is formed by circulating through the ventilation hole 16b and the ventilation slits (venting portions) 1a and 16c into the motor chamber 8, respectively.

That is, the temperature rise is high in the motor chamber 8 due to the presence of the stator winding 6 as a heat source, but the temperature in the motor upper chamber 13 is low because there is no significant heat generation source. Therefore, according to this embodiment, the air in the motor upper chamber 13 having a low temperature is supplied to the ventilation holes 16b, the ventilation slits 16c,
1a into the motor chamber 8 and the upper bearing 17
And the temperature inside the motor chamber 8 can be positively reduced.

Incidentally, as shown in FIG.
By providing the projection 16d on the bracket 16 so that the axial gap between the rotor fin 21 and the rotor fin 21 does not increase by a certain amount or more, it is possible to partition the air circulation path of the rotor fin 21 and increase the cooling efficiency.

The circulating flow of air from the rotor fins 21 removes heat from the stator windings 6 and raises the temperature thereof. The temperature of this circulating flow flows into the motor upper chamber 13 covered by the motor cover 15. Then, the air is mixed with the low-temperature air in the motor upper chamber 13 and cooled.
Cooling fins 15a on the outer wall in contact with air or water
By providing the cooling fins 15b on the inner wall in contact with the circulating flow, the heat transfer area can be increased and the temperature reduction effect can be further enhanced.

In this embodiment, an example is shown in which ventilation portions are provided in both the bracket 16 located on the outer diameter side of the upper bearing 17 and the main shaft 1 located on the inner diameter side. It may be provided on one side.

[0028]

As described above, according to the present invention, the stator windings and the upper bearing of the submersible pump can be effectively cooled, whereby the service life of the submersible pump can be extended or the motor can be cooled. Can be reduced in size.
Further, since the temperature of the upper bearing can be reduced, generation of abnormal noise or vibration due to outflow of grease or the like can be prevented, and the life of the submersible pump can be extended.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional front view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main shaft 1a Vent slit (vent part) 2 Motor part 3 Pump part 4 Mechanical seal 5 Rotor 6 Stator winding 7 Stator 8 Motor room 13 Motor upper room 15 Motor cover 15a, 15b Cooling fin 16 Bracket 16a Vent hole (vent part) 16b Vent hole (vent part) 16c Vent slit (vent part) 17 Upper bearing 21 Rotor fin 25 Impeller

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI H02K 9/10 H02K 9/10

Claims (5)

[Claims] A motor unit and a pump unit are integrally provided, the motor unit including a motor chamber for storing a rotor and a stator;
A motor upper chamber covered by a motor cover above the upper chamber; and a bracket for partitioning the motor chamber and the motor upper chamber and holding an upper bearing. In the submersible pump provided with the rotor fins, the bracket, the motor chamber and the motor upper chamber communicate with each other, so that a ventilation hole is provided on a larger diameter side than a position facing the rotor fins, and near the upper bearing. A submersible pump characterized by having a ventilation part. 2. A vent hole is provided in one or both of the upper and lower bearings located on the inner diameter side and the outer diameter side, and an air flow path is formed between the motor chamber and the motor upper chamber. The submersible pump according to claim 1, wherein 3. The submersible pump according to claim 2, wherein the ventilation portion provided on the inner diameter side of the upper bearing is a ventilation hole provided on a main shaft. 4. An axial space between the rotor fin and a ventilation hole on the motor chamber side of a bracket that separates the motor chamber and the motor upper chamber, between the large-diameter ventilation hole and the upper bearing. 2. A submersible pump according to claim 1, wherein a cylindrical projection is provided so that the diameter of the submersion does not increase. 5. The submersible pump according to claim 1, wherein cooling fins are provided on an outer wall and an inner wall of the motor cover.