JPH06315239A - Canned motor pump - Google Patents

Abstract

PURPOSE:To obtain a canned motor pump in which accident due to leak is eliminated by enhancing the watertightness of a can for isolating the stator chamber and the rotor chamber. CONSTITUTION:The canned motor pump comprises a plurality of cans 11, 12 for isolating the stator chamber 2 and the rotor chamber 3 wherein the cans 11, 12 are secured watertightly to the motor casing 13 and the end bracket 15, respectively, thus enhancing the watertightness of the cans 11, 12. A dew formation sensor 19 is disposed in the space between the plurality of cans 11, 12 in order to stop a motor upon intrusion of water from a can on the rotor chamber 3 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a canned motor pump, and more particularly to a canned motor pump suitable for a hot water circulation pump and the like.

[0002]

2. Description of the Related Art The contents and structure of the prior art will be described with reference to FIG. A stator 4 in which a winding 6 is wound is provided in a stator chamber 2 surrounded by a motor casing 13 and an end bracket 15, and a first can formed of a non-magnetic material on the inner circumference of the stator 4. 11, a motor casing 13 and an inner end surface of the end bracket 15 are watertightly fixed to each other by a first O-ring 17 to form a rotor chamber 3 inside the first can 11. A rotor 7 fixed to a rotary shaft 9 rotatably supported by bearings 10 provided on the motor casing 13 and the end bracket 15 is disposed in the slave chamber 3, and the rotary shaft 9 protruding from the motor casing 13 is disposed. The impeller 16 is fixed to the pump chamber 1, and the pump chamber 1 surrounded by the pump casing 14 and the motor casing 13 provided on the outer periphery of the impeller 16 is formed.

The winding 6 wound around the stator 4
A rotating magnetic field is generated on the inner peripheral surface of the stator 4 by passing an appropriate electric current to the rotor 4, and the rotor 7 is driven to rotate around the first can 11, thus driving the integral impeller 16 to form a pump. It fulfills the function of.

[0004]

The conventional structure as described above has the above-mentioned structure when the first can 11 is damaged or when the first can 11 is broken.
There was a problem that when the ring 17 deteriorated, hot water flowed into the stator chamber 2 from the rotor chamber 3 and electric current leaked from the winding 6.

[0005]

A canned motor pump according to the present invention is constructed such that a can made of a plurality of non-magnetic materials is individually watertightly fixed to a motor casing and an end bracket.

[0006]

[Operation] In the above-mentioned structure, the plurality of cans are not damaged at the same time, and the leakage current from the winding can be prevented.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a canned motor pump according to the present invention. What is different from the conventional example shown in FIG. 2 is that the can has a double structure and a humidity sensor is arranged. .

In FIG. 1, the second can 12 is watertightly fixed to the motor casing 13 and the end bracket 15 by a second O-ring 18 via a small gap with the first can 11. Therefore, even if the second can 12 is damaged, the first can 11 moves from the rotor chamber 3 to the stator chamber 2
Prevents warm water from flowing into. Further, since the dew condensation sensor 19 is arranged in the space 20 surrounded by the first can 11, the second can 12, the motor casing 13, and the end bracket 15, the second can 12 is damaged and the space 20 is removed.
Since the hot water that has flowed in can be detected, leakage of current from the winding 6 can be prevented by stopping the energization of the winding 6 before the first can 11 is damaged.

[0009]

The canned motor pump according to the present invention is
Due to the above-mentioned configuration, even if the second can is damaged, the first can can prevent the hot water from flowing into the stator chamber, and the dew sensor can detect the hot water to stop the energization. There is no effect, and the reliability is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of the structure of a canned motor pump according to the present invention.

FIG. 2 is a cross-sectional view showing an example of the structure of a conventional canned motor pump.

[Explanation of symbols]

 1 Pump Room 2 Stator Room 3 Rotor Room 4 Stator 5 Iron Core 6 Winding 7 Rotor 9 Rotor Shaft 10 Bearing 11 First Can 12 Second Can 13 Motor Casing 14 Pump Casing 15 End Bracket 16 Impeller 17 Number 1 O-ring 18 2nd O-ring 19 Condensation sensor 20 Space

Claims (2)

[Claims] 1. A stator around which a drive winding is wound is arranged in a stator chamber surrounded by a motor casing and an end bracket, and a non-magnetic member is provided on the inner circumference of the stator inside the motor casing and the end bracket. A rotor fixed to a rotary shaft rotatably supported by bearings provided on the motor casing and the end bracket is arranged in a rotor chamber that is watertightly fixed to the inside of the non-magnetic member. In a canned motor pump in which an impeller is provided on a rotary shaft protruding toward a motor casing side, and a pump casing is provided on the outer circumference of the impeller, the non-magnetic member is composed of a plurality of cans, each can being the motor casing and an end bracket. A canned motor pump characterized by being watertightly adhered to each. 2. The canned motor pump according to claim 1, wherein a dew condensation sensor is arranged in a space surrounded by the plurality of cans, the motor casing, and the end bracket.