JPS5872347A - Insulation for slot and method thereof - Google Patents

Abstract

PURPOSE:To improve the insulating strength to ground and to improve the inserting property of a coil by integrating by heating resin adhered to the end of a slot and a core end surface with a heat fusible sheet material provided in the slot. CONSTITUTION:A composite material produced by coating or bonding in a film shape thermoplastic resin 7 such as copolymer nylon having a melting point of 200-230 deg.C such as polyester film 6 on one or both side surfaces of the interior of a slot 2 of a core 1 is inserted in the same length as the length of the thickness of the laminated core 1, powder resin such as epoxy resin is adhered, for example, by an electrostatically dipping method on the end surface of the slot 2 and the end surface of the core 1, thereby forming a powder resin layer 8. Then, the resin 7 and the layer 8 are fused and cured, thereby forming an insulating layer 9 continued from the slot 2 over the end surface of the core 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground insulating device installed in a slot of an iron core of a rotating electrical machine, etc. As slot insulation, a heat-sealable sheet material or a heat-sealable layer is applied on one or both sides of the slot. The insulation strength between the ground and the ground is improved by combining the method of inserting a sheet material such as a coated polyester film and the powder insulation coating method.

The present invention relates to a slot insulating device with improved coil insertability and improved thermal conductivity inside the slot, and a method for manufacturing the same.

Conventionally, the insulation of electric machine windings in which randomly wound coils are housed in the slots of the stator core of rotating electric machines, etc., is as shown in the cross-sectional view of the main part in Figure 1. A U-shaped slot insulator 3 made of polyester film or the like is installed inside the slot insulator 2, and a randomly wound coil 4 made of a synthetic resin enamelled wire such as a polyester wire is housed in the slot insulator 3. A wedge 5 made of a polyester film or the like is formed into a U-shape from the wrapped part 3, and a randomly wound coil 4 is fixed thereto.

The slot insulator 3 shown in FIG. 1 is used to prevent the core 1 from shifting in the stacking thickness direction when the irregularly wound coil 4 is inserted, and to maintain the insulation strength between the coil and the ground, as shown in FIG. 2.

The folded part 3 is the part of the slot insulator 3 that protrudes from the iron core 1.
It is inserted into slot 2 with a shape marked with a. Currently, in the above insulation structure, for the slot insulator 3, there is a method of directly forming an insulation coating on the inner wall of the slot 2 of the iron core 1, in other words, a powder insulation coating method, instead of inserting a sheet material. Volume 1. It is being put into practical use in low voltage machines. however.

In the powder insulation coating method, when the core 1 has a long stack and the slot 2 has a relatively small cross-sectional area, the problem is due to the uniformity of the coating inside the slot 2 and the hard and strong nature of the powder insulation layer. There are many problems in practical applications such as the occurrence of cracks and peeling due to thermal and mechanical stress.Furthermore, with the conventional sheet material insertion method, when attempting to shorten the coil length and improve insertability, the sheet material The object of the present invention was made in view of the above-mentioned circumstances, and it was made in the form of a heat-fused sheet. The material is insulated inside the slot, and the powder resin is made of pure ml! A method such as the dynamic dipping method is used to attach the material to the slot end and both end faces of the core, and by heating, the sheet material inside the slot and the powder resin are simultaneously fused, melted and solidified, and integrated, and a continuous insulating layer is formed on the end face of the core. The purpose is to provide slot insulation for formed cores.

The configuration of the present invention will be explained. The structure of the present invention is made of a material that semi-melts within the core slot at temperatures below 200 to 230°C, or a composite material that has a self-adhesive layer formed on one or both sides of conventionally used polyester film, etc. It is constructed by combining the slot insulation by the method and the insulation formation of the slot end and the iron core both 1WJ by the electrostatic dynamic dipping method of powder m fat.One example is shown in Fig. 3.
The figure is a cross-sectional view of the slot in the core stacking thickness direction.
A composite material coated with a thermoplastic resin 7 having a melting point of 230°C or lower, such as copolymerized nylon, or bonded as a film, is inserted in a U-shape with the same length as the stacked thickness of the iron core 1, and then inserted into the slot. After forming the insulation, the insulating layer 8 was formed by attaching a powder resin such as epoxy resin to the end surface by electrostatic dipping or the like, 200-2.
Slot 2 is formed by heat treatment at a temperature of 30°C.
The thermoplastic resin film 7 inside the slot 2 is melted, and the powder resin layer is also melted and hardened to be integrated.After cooling, as shown in FIG. A thermoplastic resin 7 is melted and filled to fill the gap therebetween, and at the end of the core, the in-slot sheet insulation and the powder insulation layer 8 are integrated, and extend from inside the slot 2 to one side of the core 1.

Together, they form a continuous insulating layer 9.

According to the ultra-fine configuration of the present invention, the insulation distance from the irregularly wound coil housed in the slot to the ground increases to the outer periphery of the core, improving dielectric strength, and the powder resin coating formed on the end face of the core serves as ground insulation. If it can be utilized, the length of the coil end outside the core slot in the core thickness direction can be shortened. Furthermore, since there is no protrusion of the slot insulator from the end of the iron core, the length of the coil can be shortened by about 5 to 10 mm compared to the conventional method, and the wire material can be reduced and the device can be made smaller. Inside the slot, the heat-fusion layer fills and adheres between the slot insulator and the slot inner wall, eliminating voids, so the thermal conductivity from the coil in the slot to the iron core is about 1.
Improved by 5 to 1.8 times, reducing coil temperature rise (5 to 1.8 times)
10 inch reduction).

Furthermore, if the insulating material in the form of a sheet to be inserted into the slot is pasted with heat-adhesive resin on both sides of the polyester fill base, or if the whole is made of heat-adhesive resin, the heating after the randomly wound coil is inserted will be prevented. The random winding coil and slot are stuck together,
It has the effect of improving mechanical strength and heat transfer properties.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main part of the slot according to the conventional method, #I2
The figure is a perspective view of the slot end of the conventional method, and FIG. 3 is a sectional view of the main part of the slot before heat treatment in the core thickness direction according to the present invention.
FIG. 4 is a sectional view of the main part of the slot of the heat treatment wave in the direction of the core stack thickness according to the present invention. 1... Iron core 2... Slot 6... Polyester film 7... Thermoplastic resin 8... Powder resin insulation layer 9...
...Insulating layer (7317) Representative patent attorney Noriyuki Chika (and 1 others)
Figure 1 Figure 2 Figure 3 Figure 4 / / -2 (

Claims (1)

[Scope of Claims] 1) In slot insulation performed in slots provided in an iron core, a sheet-like film made of heat-meltable resin is provided in the slot in close contact with the iron core, and a single sheet-like film is provided on the end face of the iron core. Slot insulation characterized by having an integral insulation layer made of powdered resin covering the end face of the film. 2) 1! The sheet-like film made of heat-molten resin provided in the slot is a copolymerized nylon film! ! !
A slot insulation according to claim 1, characterized in that 3) The slot insulation according to claim 1, wherein the sheet-like film provided in the slot is a polyester film with heat-melting resin adhered to the surface. 4) Insert a sheet-like film made of resin that melts by heating into the slot provided in the core to approximately the same length as the end face of the core to cover the inside of the slot. Powdered resin is applied to the surface using an electrostatic dynamic dipping method. A slot insulation method in which a sheet film and powdered resin are melted together by heating to form an integrated insulation layer.