JPH0139082Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a submerged canned motor, especially a submerged canned motor for driving a submersible pump that can be used in relatively high temperature liquids of about 70 to 80°C such as hot spring water. The present invention relates to a submerged canned motor whose internal space is separated by a can into a stator chamber and a rotor chamber. Conventionally, this type of motor uses fresh water or an equivalent special liquid in the stator chamber, so the liquid temperature has been limited to a maximum of about 50°C. The reason for this is poor lubrication of the bearing metal due to an increase in the temperature of the motor sealed fluid.

Therefore, in order to solve this problem, the first step in this idea is to prevent poor lubrication of the bearing metal by using a liquid with a high boiling point as the motor's sealed liquid, and to make the motor usable in high-temperature liquids. is being carried out.

On the other hand, the interior space of the stator is conventionally filled with resin, which has the effect of dissipating heat generated from the stator and windings to the outside. There is a risk of damage to the stator can due to volumetric expansion. In this invention, in order to further prevent this, the above-mentioned liquid is placed in the stator chamber, and a liquid with a boiling point higher than water is separately filled in the rotor chamber.
In order to prevent a pressure increase, the volume expansion caused by the ambient temperature and the heat during motor operation is performed without resistance, and the volume of the space occupied by the liquid increases as the liquid expands. It is equipped with an absorption device.

However, as a liquid with high insulation properties and a high boiling point,
Mineral oil, mineral oil, silicone oil, etc. are used, and silicone oil is particularly suitable.

Referring to the drawings, each of the drawings in FIGS. 1 to 4 shows a different embodiment of the invention, and the same reference numerals represent the same parts.

FIG. 1 shows a first embodiment of this invention, 1
0 is a rotor, 11 is a stator, 12 is a frame, 3
1 is a main shaft fixed to the rotor, and 26 is a stator can, which separates the rotor chamber 8 from the stator chamber 27. A mechanical seal chamber 7 communicates with the rotor chamber 8. The mechanical seal 5 prevents external liquid from entering the mechanical seal chamber. 13 is the lower bracket, 15 is the thrust disk, 16 is the lower thrust bearing, 1
7 is a rolling ball, 18 is a lower centering collar, 19 is a thrust housing, 20 is a lower radial metal, 21
is the upper radial metal, 22 is the mounting flange, 2
3 is a lead wire, 24 is a sand slinger, and 32 is a small hole drilled in the lower bracket, whereby the rotor chamber 8 and the thrust bearing chamber 29 are constantly communicated.

A liquid with a high boiling point is filled in the motor internal space (rotor chamber 8, thrust bearing chamber 29, mechanical seal chamber 7), and a liquid with a high boiling point is also filled in the stator chamber 27. A space 14 is formed in the stator chamber 27 to absorb the volumetric expansion of the enclosed liquid that occurs when the motor is installed and operated in high-temperature liquid and to prevent deformation of the can 26. Furthermore, since the stator coil 9 is always covered with oil, the heat generated in the coil 9 is carried to the frame 12 via the liquid in the stator chamber 27. On the other hand, a pipe 3 is provided and connected to the oil tank 2 in order to absorb the volumetric expansion of the liquid sealed in the motor internal space (rotor chamber 8, thrust bearing chamber 29, mechanical seal chamber 7). 25 indicates oil.

If the mechanical seal 5 reaches the end of its life or is damaged after the start of operation, external liquid will enter the rotor chamber 8 which is connected to the mechanical seal chamber 7. However, even in this case, since the stator chamber 27 is partitioned by the rotor chamber 8 and the can 26, the external liquid does not come into contact with the stator coil 9, so there is no risk of insulation deterioration. Further, if the sealed oil in the mechanical seal chamber 7 leaks from the mechanical seal 5, it is detected by the level switch 1 attached to the oil tank 2.

In the embodiment shown in FIG. 2, the apparatus of FIG.
The piping 3 is eliminated and a bellows 28 is installed in the mechanical seal chamber 7, and the motor internal space (mechanical seal chamber 7, rotor chamber 8, thrust bearing chamber 29)
absorbs the volumetric expansion of the filled liquid.

In a third embodiment shown in FIG.
Unlike the embodiments shown in Figs. 2 and 2, a mechanical seal 6 is added to the mechanical seal chamber to isolate the mechanical seal chamber 7 from the rotor chamber 8, so that even if external liquid enters the mechanical seal chamber, the rotor can be removed immediately. I have learned not to enter the room. Therefore, the volume absorption pipe 3 is also connected to the rotor chamber 8 by a branch pipe 3', and the volume expansion of the liquid sealed in the mechanical seal chamber 7 and the volume expansion of the liquid sealed in the rotor chamber 8 and the thrust bearing chamber 29 are performed. and absorb each. In addition, a chamber 4 is provided in the piping 3 to prevent external liquid from entering the mechanical seal chamber 7 due to the expiration of the life of the mechanical seal 5 or its breakage, and the liquid to be used for the stirring action of the mechanical seals 5 and 6. It becomes turbid and its expansion action prevents it from reaching the pipes.

In a fourth embodiment shown in FIG. 4, a diaphragm device 30 is provided in the stator chamber in place of the space 14 in the stator chamber 27 in FIG. This has the effect of absorbing the pressure, reducing the differential pressure across the can 26, and preventing deformation of the can 26.

This invention has such a configuration and provides a motor that can be used in high-temperature liquids, which was previously impossible, by using oil with high insulation properties and a high boiling point as the liquid sealed in the motor. I was able to do that. Furthermore, in the motor of this invention, by covering the stator chamber with a can, it is possible to prevent insulation failure even if external liquid should enter the rotor chamber from the mechanical seal chamber.

[Brief explanation of the drawing]

1 to 4 show different embodiments of the motor of this invention. Explanation of symbols, 1... Level switch, 2... Oil tank, 3, 3'... Piping, 4... Chamber, 5, 6... Mechanical seal, 7... Mechanical seal chamber, 8... Rotor chamber , 9... stator coil, 10... rotor, 11... stator, 12...
...Frame, 13...Lower bracket, 14...
Absorption space, 15... Thrust disk, 16...
Lower thrust bearing, 17...Rolling ball, 18
...Lower alignment collar, 19...Thrust housing, 20...Lower radial metal, 21...Upper radial metal, 22...Mounting flange, 23...
...Lead line, 24...Sandslinger, 25...
...Oil, 26...Kyan, 27...Stator chamber,
28... Bellows, 29... Thrust bearing chamber, 30... Diaphragm, 31... Main shaft, 32
...Small hole.

Claims (1)

[Claims for Utility Model Registration] (1) A submersible pump for a submersible pump that handles particularly high-temperature liquid, where the internal space of the motor is separated by a can 26 into a stator chamber 27 and a rotor chamber 8. In the canned motor, a liquid having high insulating properties and high thermal conductivity is sealed in the inner space of the stator chamber 27, and the volumetric expansion of this liquid due to the ambient temperature and heat during motor operation is In order to ensure that this occurs without resistance, absorption devices 28, 3, 3' are provided to prevent a pressure increase in the stator chamber 27, which is configured such that the volume of the space occupied by the liquid increases as the liquid expands. Furthermore, a submerged canned motor is characterized in that by separately sealing a liquid with a boiling point higher than water in the rotor chamber 8, it is possible to use the motor in a high-temperature liquid such as hot spring water. (2) The submerged canned motor according to claim 1, wherein the absorption device is an absorption space 14 provided in the stator chamber 27.