JPH06276713A - Can forming method for canned motor - Google Patents

Abstract

PURPOSE:To provide a can forming method for a canned motor in which close adhesion between the inner circumferential surface of a stator iron core and the outer circumferential surface of a fluororesin lining constituting a can be smoothly made. CONSTITUTION:Backing treatment is applied to the inner circumferential surface of a stator iron core 3 and the inner circumferential surface of a reinforcing tube 11, 12 as occasion demands, and after a fluorioresin lining is so formed in advance that both ends thereof are shrunk in drum-like form having a jaw and then are fitted into the inner circumferential surface of a stator core 3 together with the inner circumferential surface of the reinforcing tubes 11, 12, an exciting coil for heating use is provided on the inner circumference side of the stator iron core 3 through the lining. Further, high-frequency induction heat is applied to the iron core side 3, and at the same time hot air or the other heat accelerating medium is applied to the inner circumference side of the lining as occasion demands and at the same time heating and pushing force are simultaneously applied outward from the inside of the lining, so that the resin lining closely adheres to the inner circumferential surface of the iron core 3 in one body due to the expansion for recovering the original form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetically sealed electric motor using a resin can, and more particularly to a can motor for driving a compressor in which the refrigerant is an ammonia.

[0002]

2. Description of the Related Art Conventionally, a canned motor has a hermetically sealed structure in which the fluid is leaked from a drive bearing portion of a driven fluid machine, and the fluid is leaked from the atmosphere side of the motor. The insulator of the subsidiary coil is not isolated from the fluid, so that the stator coil is isolated. This type of canned motor allows high-density alternating magnetic flux from the stator core and stator wire to pass through to the rotor, but the air gap needs to be designed to a narrow value unless it interferes with the rotation of the rotor. Therefore, the thickness of the cylindrical can inserted into the space must be thin and have pressure resistance.

That is, electromagnetically, it has a high permeability characteristic that a high-density alternating magnetic flux permeates through a can, an eddy current does not flow due to the high-density alternating magnetic flux, and eddy current loss does not occur mechanically. The can is electromagnetically and mechanically sealed and has a pressure resistance and deformation resistance against the internal and external pressures of the can, and is chemically resistant to the target gas and liquid on the load side. , Chemically exposed to extremely severe conditions. For this reason, a thin cylindrical metal can is generally used for the can, but a large eddy current loss occurs because an alternating magnetic flux is transmitted in the metal can, and this causes a large eddy current loss. The reduction in efficiency is so large that it cannot be ignored, and for this reason, a special cooling device is required.

Therefore, a structure using a thin resin can as the can is being studied. However, the thin resin can has mechanical and structural problems such as air tightness and pressure resistance. For this reason, a special reinforcing material with electrical insulation and a resin are being developed to increase the exciting current and decrease the eddy current.Although such a can has excellent electrical characteristics, it has a large capacity, It is difficult to deal with various models, manufacture them, and attach them to the inner circumference of the iron core. As a result, new problems arise in mechanical structure such as air tightness and pressure resistance. For this reason, a can with a resin lining is considered. As a result, the loss due to the can described above can be completely eliminated, and the efficiency characteristics similar to general-purpose machines and the need for a special cooling device are eliminated, but especially when using an ammonia as a refrigerant, the case of using the resin lining There were inadequate points in material, processing, etc., and we had to solve this problem.

[0005]

That is, when the compressor refrigerant is ammonia, the resin for pressure resistance and corrosion resistance is limited by itself, and the material is limited to fluororesin, but the resin is melted. Since the temperature is as high as around 300 to 400 ° C., it is difficult to work and adhere. For example, in the case of using the fluororesin lining, for example, the stator coil on which the stator coil is wound is heated in a high-temperature furnace as it is, and the fluorocarbon resin is lined on the inner peripheral surface of the stator core. However, in this processing and process, since the insulator covering the stator coil is burned because it is heated to a high temperature, it becomes unusable and the resin lining process becomes impossible. Therefore, it is unavoidable to form the lining can in advance and mechanically insert the lining can into the core, but this constitutes the inner peripheral surface of the stator core and the can. It is difficult to say that the adhesiveness with the outer peripheral surface of the fluororesin lining is sufficient, and it is easy to cause inconvenience.

The present invention solves such a development problem, and even when the fluororesin lining is used, the insulator covering the stator coil is not burned and the inner peripheral surface of the stator core and the can are constituted. An object of the present invention is to provide a method for forming a can of a canned motor that can smoothly adhere to the outer peripheral surface of a fluororesin lining.

[0007]

The present invention has been made in view of this point, and a lining can is molded in advance, and a cylindrical fluororesin lining is used as the can.
Fit into the inner peripheral surface of the stator core together with the inner peripheral surface of the reinforcing tube,
While heating only the skin of the inner surface of the stator core, the resin lining is heated and softened, and a pressing force made of a fluid or a solid is applied from the inner surface of the lining, and the lining is at least the stator. The feature is that it is closely attached to the inner peripheral surface of the iron core.

In this case, specifically, after the fluororesin lining is fitted to the inner peripheral surface of the stator core together with the inner peripheral surface of the reinforcing cylinder, the exciting wire for heating is attached to the inner peripheral side of the stator core through the lining. Was installed and excited by applying a high-frequency voltage to the excitation coil, and the inner peripheral side of the iron core was heated by high-frequency induction to soften the resin and filled in the sealed space inside the lining. It is preferable that the lining is brought into close contact with and integrated with the inner peripheral surface of the iron core by utilizing the pressing force of the positive pressure fluid.

In a further preferred embodiment, the inner circumference of the stator core and, if necessary, the inner circumference of the reinforcing cylinder are subjected to a base treatment, while the fluororesin lining is previously shrink-molded into a drum shape having a brim at both ends. In this state, after fitting it to the inner peripheral surface of the stator core together with the inner peripheral surface of the reinforcing tube, a magnetizing coil for heating is installed on the inner peripheral side of the stator core through the lining, and the core side is subjected to high frequency induction heating. While applying, if necessary, while applying hot air or other heat promoting medium to the inner peripheral side of the lining, simultaneously with heating, a pressing force from the inside of the lining to the outside is applied, and by the expansion of the resin lining to return to its original shape. ,
It is preferable that the inner peripheral surface of the iron core is closely adhered to and integrated with the inner peripheral surface.

[0010]

According to the present invention, as described above, the heating exciter coil is installed inside the can which becomes the lining, and this is excited by the high frequency voltage to make the stator core and the stator core pre-treated. Only the surface of the inner circumference of the reinforcing tube is induction-heated, and at the same time, the fluororesin lining is softened by hot air or a heater or other heat-promoting medium, and at the same time both ends of the lining are adhered to the inner circumference of the iron core and baked. It was done like this. In this case, the most important thing is to heat only the skin of the inner peripheral surface of the stator core with the reinforcing cylinders on both sides by, for example, high-frequency induction current, which allows the stator coil in the groove of the stator core to be heated. The insulating material that covers is not burned out.

In this case, by making the lining end a drum-shaped can with a brim, the adhesion strength of the can to the iron core is enhanced, and when sealing as a motor, the sealing function at this part is simple and reliable. The reliability can be increased. Further, the rigidity is improved by using a lining made of a fluororesin mixture containing, for example, glass fibers, without forming the fluororesin lining only with the fluororesin.

[0012]

Embodiments of the present invention will now be illustratively described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative positions, etc. of the components described in this embodiment are not intended to limit the scope of this patent to them unless otherwise specified, and are merely illustrative examples. Nothing more than. FIG. 1 is a cross-sectional view of a fluororesin-lined canned motor formed according to the present invention, in which 1 is a canned motor 2.
Ammonia is used as a refrigerant in a refrigerant compressor driven by. 3 is a stator core inserted in the frame 4, 5 is a stator coil wound around the stator core 4, and 6 is supported by bearings 81 arranged at both ends in the axial direction through a rotary shaft 9, A rotor 10 that rotates integrally with the rotating shaft 9 is a can fixedly mounted on the inner peripheral surface of the stator core 4 and is formed of a fluororesin lining as will be described later, and the stator core will be described later. 3 and the inner peripheral surfaces of the reinforcing cylinders 11 and 12 on both sides thereof are integrally baked and fixed. Reference numerals 11 and 12 denote reinforcing cylinders having an inner diameter substantially the same as the inner peripheral surface of the stator core 4 and having a flange on the shaft end side that is abutted and fixed to the inner wall of the bearing support body 9. The iron cores 4 are arranged symmetrically on both sides in the axial direction. According to such a canned motor, the refrigerant leaking to the outside from the portion where the compressor 1 is axially supported is cut off from the outside air by the can 10 made of the fluororesin lining and the bracket portions 7 and 8 so that the compressor 1 is completely sealed. Is done.

FIG. 2 is an explanatory view showing a manufacturing process in which the fluororesin lining shown in FIG. 1 is integrally baked and fixed to the stator core 3 and the inner peripheral surfaces of the reinforcing cylinders 11 and 12 on both sides thereof. FIG. 3A shows the cylindrical fluororesin lining 101 which serves as the can. In the present embodiment, the fluororesin lining may be formed of fluororesin alone,
Even if it is formed by using a fluororesin mixture containing glass fibers, the surface of the thin cylindrical film made of non-magnetic metal such as soft aluminum is coated with fluororesin for lining. You may form. In particular, the glass fiber itself of the fluororesin mixture has a reinforcing property, and is preferable in carrying out the present invention.

Returning to FIG. 2, the stator core 3 and the reinforcing cylinders 11 and 12 are removed from the inside of the stator core 3 and the reinforcing cylinders 11 and 12 except for the rotor 6, the brackets 7 and 8, the rotating shaft 9, and the like. The inner peripheral surface side of 12 is hollow. Then, the inner surfaces of the stator core 3 and the reinforcing cylinders 11 and 12 are roughened by sandblasting or the like in order to provide adhesion to the fluororesin lining 101, and further subjected to a coating base treatment in advance. And again the stator core 3
After inserting the resin lining 10 into the inside of the frame, the high frequency induction heating coil 16 is inserted, and the side covers 13 having the pressure air insertion ports 18 and the side covers 13 and 14 having the through terminals 17 are attached to both sides of the frame 4. , Through terminal 17
The high-frequency AC power supply 15 and the heating coil 16 are electrically connected via the, and the heating power is supplied to the heating coil 16 by the high-frequency AC power supply 15. Then, air is introduced from the pressure air insertion port 18 and the high frequency induction heating wire 1 is supplied from the high frequency power supply 15.
By supplying an electric current to 6, only the inner peripheral surfaces of the stator core 3 and the reinforcing cylinders 11 and 12 are heated to a high temperature by the eddy current, and at the same time, the fluororesin lining that becomes a can is also heated and softened, and the air insertion port 18 By pressing the compressed air introduced further, the inner peripheral surface is adhered and baked to be integrated. In this case, the compressed air may be preheated and supplied as hot air, or the resin lining itself may be preheated in terms of work.

The cylindrical fluororesin lining is provided in advance with a collar 102a as shown in FIG. 3B to form a cylindrical shape 102.
After being contracted to fit into the inner peripheral surface of the stator core 3 together with the inner peripheral surfaces of the reinforcing cylinders 11 and 12, the stator core 3 is inserted through the lining 102. A heating excitation coil 16 is installed on the inner peripheral side, and the stator core 3 side is heated while applying high-frequency induction heating, while applying hot air or other heat promoting medium to the inner peripheral side of the lining as necessary. At the same time, a pressing force may be applied from the inside of the lining 102 to the outside, and the resin lining 102 may be brought into close contact with the inner peripheral surface of the stator core 3 by the expansion of the resin lining 102 to return to its original shape. 102a
Since it is sandwiched between the reinforcing cylinders 11 and 12, the adhesion strength of the can 10 to the stator core 3 as shown in FIG. 1 is increased, and when sealing as a motor, sealing is performed in this portion. The sealing function can be easily and surely performed, reliability can be increased, and a more preferable fully sealed canned motor can be configured.

[0016]

As described above, according to the present invention, a canned motor using a fluororesin as a can makes it possible to obtain the same excellent efficiency as that of a general-purpose machine, and the ammonia-free environment-friendly environment. A safe hermetic compressor drive motor for refrigerant can be configured, and since there is no eddy current loss in the can, there is no need for a special cooling device, and a large-capacity structurally simplified and energy-saving completely sealed type The electric compression device can be configured. Further, even when a fluororesin lining is used for the can, the inner peripheral surface of the stator core and the outer peripheral surface of the fluororesin lining forming the can are prevented from burning out of the insulator covering the stator coil. It is possible to obtain a canned motor capable of smoothly adhering. Further, by making the lining end part a drum-shaped can with a collar, the adhesion strength of the can to the iron core is enhanced, and when sealing as a motor, the sealing function in this part can be performed simply and reliably. , Reliability can be increased. It has various remarkable effects.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a fluororesin-lined canned motor formed according to the present invention.

FIG. 2 is an explanatory view showing a manufacturing process in which the fluororesin lining shown in FIG. 1 is integrally baked and fixed to the stator core and the inner peripheral surfaces of the reinforcing cylinders on both sides thereof.

3A and 3B show a cylindrical fluororesin lining that serves as the can.

[Explanation of symbols]

 3 Stator Iron Core 11 Reinforcement Tube 12 Reinforcement Tube 10 Can 101 Fluorine Resin Lining 102 Fluorine Resin Lining 16 Heating Excitation Wire Ring 18 Pressure Air Insertion Port 15 High Frequency Power Supply

Claims (4)

[Claims] 1. A pair of reinforcing cylinders having substantially the same inner diameter as the inner peripheral surface of the stator core are arranged and fixed on both axial sides of the stator core, and function as cans on the inner peripheral surfaces of the core and the reinforcing cylinder. In a method of forming a can of a canned motor in which a resin body is disposed, a cylindrical fluororesin lining having a substantially cylindrical shape or collars provided at both ends as necessary is preliminarily formed as a can to reinforce the lining. Fit into the inner peripheral surface of the stator core together with the inner peripheral surface of the cylinder, while heating only the skin of the inner peripheral surface of the stator core to heat and soften the resin lining, and from the fluid or solid from the inner peripheral surface side of the lining. The method for forming a can of a canned motor is characterized in that the lining is brought into close contact with and integrated with at least the inner peripheral surface of the stator iron core. 2. A magnetizing coil for heating is installed on the inner peripheral side of the stator core through the lining after fitting the fluororesin lining on the inner peripheral surface of the reinforcing cylinder together with the inner peripheral surface of the stator core. While applying a high-frequency voltage to the excitation coil to excite the inner peripheral surface of the iron core to induce high-frequency induction heating to soften the resin, the positive pressure fluid filled in the sealed space inside the lining is pushed. A method for forming a can of a canned motor, characterized in that the lining is brought into close contact with and integrated with the inner peripheral surface of the iron core by utilizing pressure. 3. An inner circumference of a stator core and, if necessary, an inner circumference of a reinforcing cylinder are subjected to a base treatment, while a fluororesin lining is shrink-molded in advance in a drum shape having flanges at both ends. After fitting on the inner peripheral surface of the stator core together with the inner peripheral surface, a magnetizing coil for heating is installed on the inner peripheral side of the stator core through the lining, while applying high frequency induction heating to the core side,
While applying hot air or other heat promoting medium to the inner peripheral side of the lining as needed, a pressing force from the inside of the lining to the outside is applied at the same time as heating, and by expansion of the resin lining to return to its original state, the inside of the iron core is expanded. The method of forming a can of a canned motor according to claim 1, wherein the can is closely integrated with the peripheral surface. 4. The method for forming a can of a canned motor according to claim 1, wherein the fluororesin lining is a fluororesin mixture containing only fluororesin or glass fibers or the like.