JPH07231600A - Canned motor - Google Patents

Abstract

PURPOSE:To facilitate rewinding work and repairing work while protecting the components against corrosion and deterioration of insulation by welding a frame side plate and a can and then fitting the frame side plate into the frame through a sealing member, e.g., an O-ring or a gasket, being set between the inner peripheral surface of the frame and the outer peripheral surface of the frame side plate. CONSTITUTION:A stator core 1 of a magnetic body is fixed with a winding 2 and connected with a lead wire 10. Flanges 3a, 3a' are formed integrally on the opposite sides of a frame 3. Frame side plates 4a, 4b are inserted which keeping a slight gap between the outer periphery thereof and the inner peripheral surface of the frame 3 with the gap being sealed by means of O-rings 8a, 8b being set on the outer periphery of the frame side plates 4a, 4b. A thin tubular can 5 is inserted into the frame side plates 4a, 4b and the stator core 1 and the can 5 is welded, at the opposite ends thereof, to the frame side plates 4a, 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a canned motor,
In particular, the present invention relates to a canned motor stator structure used in an underwater motor pump or the like.

[0002]

2. Description of the Related Art FIG. 2 is a sectional view showing a detailed structure of a conventional canned motor. As shown in FIG. 2, a winding 2 is attached to a magnetic stator core 1 and a lead wire 10 is further connected. The outer circumference of the stator core 1 is fixed to the inner circumference of the frame 3 by shrink fitting or the like. The lead wire 10 is drawn to the outside through a hole formed in the frame 3, and the gap between this hole and the lead wire 10 is the cable packing 1.
It is sealed by 1.

At both ends of the frame 3, frame side plates 4 are provided.
a and 4b are fixed by welding. Then, thin-walled cylindrical cans 5 are inserted into the inner circumferences of the frame side plates 4a and 4b and the inner circumference of the stator core 1, and both ends of the can 5 are welded to the frame side plates 4a and 4b.

The brackets 6a and 6b are bearings 1 respectively.
2a and 12b are attached and fixed directly to the frame side plates 4a and 4b by bolts 7a and 7b. O-rings 9a and 9b are provided between the brackets 6a and 6b and the frame side plates 4a and 4b so that the external liquid does not enter the motor. Further, the stator chamber 21 is normally filled with gas, oil, or resin to cool the motor.

The rotor core 16 of the rotating body is the secondary conductor 1
7 and 7 are fixed to a main shaft 13 by shrink fitting, etc., and a key 14 provided at the end of the main shaft transmits power to a driven machine such as a pump. The bearings 12a and 12b are the main shaft 13
And a thrust disk 15a shrink-fitted onto the main shaft,
It is adapted to be in sliding contact with 15b to receive a radial load and a thrust load. The motor internal liquid 19 is sealed inside the motor to lubricate the bearings. If the motor external liquid 20 is corrosive, the external liquid 20 and the internal liquid 1
The motor internal liquid is sealed by the shaft sealing device 18 so that 9 is not easily replaced.

[0006]

In the conventional canned motor described above, the insulation does not deteriorate even if the stator winding 2 and the lead wire connecting portion are submerged in water (in liquid).
The structure is such that the stator core 1, the winding 2, and the lead wire connecting portion are set in a double cylindrical container in which the frame side plates 4a and 4b and the can 5 are welded and sealed. Therefore, there are problems listed below. When it is necessary to rewind the winding, even if the can is cut and removed, the frame side plate is welded to the frame, so it interferes with the winding work, and the frame side plate must be cut to remove the frame side plate. It is necessary to weld the frame and the frame side plate again after rewinding, weld the can, and further work to correct the welding distortion of the frame side plate. It was general to replace the frame stator with a new one without replacing it. In order to weld the frame and the frame side plate, a material with good weldability had to be used. Since the frame and the frame side plate are welded, distortion occurs and it is necessary to correct the frame side plate after welding. If the external liquid is corrosive, expensive materials such as stainless steel must be used as the material for the frame and the frame side plates in order to prevent the sensitization of the frame welded structure. On the other hand, if a non-magnetic material such as stainless steel is used, there is a drawback in that the frame cannot be used as a part of the stator yoke portion for the passage of magnetic flux. If the frame and the bracket are made of different materials, a corrosive battery is formed by the external liquid in the vicinity of the joint surface, and the vicinity of the joint surface may be locally corroded. When the thrust force generated by the pump was received by the bearing of the motor, stress was applied to the frame weld and stress corrosion was likely to occur near the weld.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a canned motor in which rewinding and repair of windings are easy, corrosion of each part of component parts does not occur, and insulation does not deteriorate. .

[0008]

In order to achieve the above-mentioned object, the present invention is directed to a motor core, frame side plates arranged at both ends of the motor frame, and a cylindrical thin-walled can fixedly mounted on the inner circumference of the stator core. In a canned motor in which the connection between the winding wire and the lead wire is sealed, the frame side plate and the can are welded, and a sealing material such as an O-ring or a gasket is interposed between the frame inner peripheral surface and the frame side plate outer peripheral surface. By fitting the frame side plate inside the frame, the stator core, the winding, and the winding and the lead wire connecting portion are hermetically sealed.

[0009]

According to the present invention, the frame and the frame side plate are not welded, but sealed with a sealing material such as an O-ring or a gasket. The bracket is fixed directly to the frame with fasteners such as bolts, and the frame side plate is fixed to the inner peripheral surface of the frame so that it does not come into contact with external liquid. The frame material is the same as the bracket material, and cast iron, which has poor weldability but is inexpensive, is the standard material. This eliminates the risk of corrosion of the welded part and local corrosion due to dissimilar materials, facilitates remounting by easily removing the frame side plate, and makes it possible to manufacture inexpensively using inexpensive materials. Is.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a canned motor according to the present invention will be described below with reference to FIG. In FIG. 1, components having the same functions and functions as those of the components of FIG. As shown in FIG. 1, a magnetic stator core 1 has a winding 2 attached thereto and a lead wire 10 connected thereto. The outer circumference of the stator core 1 is fixed to the inner circumference of a cast iron frame 3 as a standard material by shrink fitting. The lead wire 10 is drawn out to the outside through a hole formed in the frame 3, and the gap between the hole and the lead wire 10 is sealed by a cable packing 11.

At both ends of the frame 3, flanges 3a, 3
b is integrally formed. And the frame side plate 4
The outer peripheries of a and 4b are fitted with a slight gap with the inner peripheral surface of the frame 3, and these gaps are inserted into the frame side plates 4a and 4b.
It is sealed by O-rings 8a and 8b provided on the outer periphery of. Thin-walled cylindrical cans 5 are inserted into the inner peripheries of the frame side plates 4a and 4b and the stator core 1, and both ends of the can 5 are welded to the frame side plates 4a and 4b. And the frame side plate 4a generated by this welding,
The minute strain of 4b is absorbed by the gap between the frame 3 and the frame 3 and the fitting portions of the frame 3 and the brackets 6a and 6b are hardly affected by the size and assembling accuracy.

The brackets 6a and 6b are bearings 1 respectively.
2a and 12b are attached to the flanges 3a and 3 of the frame 3
It is directly fixed to b by bolts 7a and 7b. O-rings 9a, 9 are provided to prevent external liquid from entering the inside of the motor from between the brackets 6a, 6b and the flanges 3a, 3b.
Although sealed by b, the O-rings 9a, 9b are the frame 3, the frame side plates 4a, 4b and the bracket 6a,
The O-ring 8 can be placed by placing it in the part sandwiched by 6b.
a and 8b do not directly touch the motor internal liquid 19,
Even if the frame 3 of the O-rings 9a and 9b is corroded by the motor internal liquid 19, the O-ring has a double structure, and the O-ring has a double structure for protecting the stator chamber 21 from water and the like. The safety against the insulation deterioration accident of the wire 2 is improved. The stator chamber 21 is normally filled with gas, oil, or resin to cool the motor.

The rotor core 16 of the rotating body is the secondary conductor 1
7 and 7 are fixed to a main shaft 13 by shrink fitting, etc., and a key 14 provided at the end of the main shaft transmits power to a driven machine such as a pump. The bearings 12a and 12b are the main shaft 13
And a thrust disk 15a shrink-fitted onto the main shaft,
It is adapted to be in sliding contact with 15b to receive a radial load and a thrust load. Further, the motor internal liquid 19 is sealed in the motor for lubricating the bearings. If the motor external liquid is corrosive, the external liquid 20 and the internal liquid 19
The motor internal liquid is sealed by the shaft sealing device 18 so as not to be easily replaced.

The frame 3 and the brackets 6a, 6b are made of the same material, and when used in general water, they are generally made of cast iron. Also, in seawater with a high chlorine concentration, nickel-impregnated cast steel, bronze, etc. can be used, and since it is not necessary to consider weldability, it is possible to make a casting of the same material as necessary, and local corrosion will occur. Difficult and reliable.

Further, when the frame material is cast iron or cast steel, the frame is a magnetic material and can pass a magnetic flux as a part of the stator core yoke portion, so that the frame is made of a non-magnetic material like a conventional canned motor. The power factor of the motor is improved as compared with the case of using the stainless steel material.

[0016]

As described above, according to the present invention, the following excellent effects can be obtained. Since the frame and the side plate are not welded but sealed by a sealing material such as an O-ring or a gasket provided between the inner peripheral surface of the frame and the outer peripheral surface of the side plate, the side plate is simply fitted into the frame, the can is removed. For example, the side plate can be easily removed and reattached, so that the rewinding and repair of the winding can be easily performed, and the waste material is only the can. Since the frame is directly joined to the bracket by fasteners such as bolts, the frame and side plates are not welded, and the side plates do not contact external liquid, the frame can be made of cast iron etc. of the same material as the bracket, and it is inexpensive. At the same time, the frame and the bracket do not form a corrosive battery on the liquid contact surface outside the motor, and local corrosion is unlikely to occur on the mating surface of the frame and the bracket. In addition to a sealing material such as an O-ring or gasket provided between the inner peripheral surface of the frame and the outer peripheral surface of the side plate, a sealing material such as an O-ring or gasket is installed on the portion sandwiched between the inner peripheral surface of the frame and the end surface of the side plate and the bracket. By adding it, it is possible to prevent the liquid inside the motor from entering the stator,
The reliability against insulation deterioration is improved. Since the frame and the side plate are not welded, local corrosion of the sensitized portion due to welding does not occur, and reliability against insulation deterioration due to intrusion of external liquid into the stator is improved. Since the frame can be made of magnetic material such as cast iron or cast steel, part of the magnetic flux of the motor stator easily passes through and becomes part of the stator core yoke, which reduces the magnetic flux density of the stator yoke and improves motor performance. To do.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing a conventional canned motor.

[Explanation of symbols]

 1 Stator core 2 Winding 3 Frame 4a, 4b Frame side plate 5 Can 6a, 6b Bracket 7a, 7b Bolt 8a, 8b O-ring 9a, 9b O-ring 10 Outlet wire 11 Packing 12a, 12b Bearing 13 Main spindle 14 Key 15a, 15b Thrust Disk 16 Stator core 17 Secondary conductor 18 Shaft sealing device 19 Motor internal liquid 20 Motor external liquid 21 Stator chamber

Claims (3)

[Claims] 1. A canned motor in which a stator core, windings, and a connecting portion between a winding and a lead wire are hermetically sealed by a motor frame, frame side plates arranged at both ends of the motor frame, and a cylindrical thin-walled can fixedly mounted on an inner circumference of the stator core. At
By welding the frame side plate and the can and inserting a frame side plate inside the frame with a sealing material such as an O-ring or a gasket interposed between the frame inner peripheral surface and the frame side plate outer peripheral surface, the stator core, the winding, and A canned motor characterized in that the connection between the winding and the lead wire is sealed. 2. The frame and brackets provided at both ends of the frame are directly fixed by fasteners such as bolts, and at a portion sandwiched between the inner peripheral surface of the frame and the frame side plate and the bracket. The canned motor according to claim 1, further comprising a sealing material such as an O-ring or a gasket. 3. The canned motor according to claim 1, wherein the frame is made of a magnetic material such as cast iron or cast steel.