JPS6046763B2 - Winding wire for water-sealed submersible motors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to improvements in heat resistance, insulation properties, etc. of windings for water-sealed submersible motors.

Conventional windings for water-sealed submersible motors are made by applying a synthetic resin such as formal or polyester to a thickness of 0.025 to 0.05 on a copper wire 1 such as annealed copper wire, as shown in Figure 1. A shielding layer 2 is formed, and an insulating layer 3 made of polyethylene or crosslinked polyethylene (hereinafter simply referred to as polyethylene) is laminated thereon, and if necessary, a protective layer 4 made of nylon coating against mechanical external forces is formed thereon. was forming.

However, in such conventional winding wires, polyethylene is used as the insulating layer 3, but this polyethylene has a low heat deformation temperature of 55 to 60 °C and a melting point of 108 to 60 °C.
Since the temperature is as low as 1200C, the winding temperature rises during motor operation and exceeds 60°C, causing thermal deformation of the windings and thinning of the insulating layer 3 in some areas, which eventually breaks down the electrical insulation and prevents motor operation. It becomes possible. Especially when the water temperature is 80-9, such as in hot springs.
When used in temperatures that reach 00C, the temperature of the windings inside the motor reaches 120 to 130C, which exceeds the melting point of polyethylene, which has the disadvantage that it cannot be used in such special environments. . This invention was made in order to eliminate the above-mentioned drawbacks, and has excellent heat resistance and insulation properties in high-temperature water, as well as hydrolyzability and mechanical strength, and is easy to laminate and can be made thinner. An object of the present invention is to provide a winding for a water-sealed submersible motor that can reduce the size and weight of the motor.

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3.

FIG. 2 is a sectional view showing an embodiment of a winding for a water-sealed submersible motor according to the present invention. A shielding layer consisting of an enamel layer of formed polyamide"imide resin, 6
7 is an insulating layer of methylpentene resin laminated as a main insulation layer on the shielding layer 5, and 7 is a mechanical insulating layer made of polyvinylidene fluoride or ethylenetetrafluoroethylene copolymer that is coated on the insulating layer 6 as needed. It is a protective layer against external forces. That is, the first shielding layer 5 on the copper wire 1
The polyamide-imide resin forming the resin has excellent heat resistance, can be used satisfactorily in H class (180°C), and also has good hydrolysis resistance.

The second insulating layer 6 is made of methylpentene resin, and its composition is a polyolefin polymer based on 4-methylpentene-1, which is obtained by dimerizing polypropylene. This methylpentene resin has a high melting point of 240'C, has excellent underwater insulation properties, and has a longer service life than conventionally used polyethylene resin when connected underwater.It also has excellent moldability, and has thin laminated layers. Since it can be easily processed, the entire winding and, by extension, the electric motor can be made smaller and lighter. Furthermore, this methylpentene resin can be manufactured as a tape or film, making it possible to completely integrate the windings at the connection part.Also, the water absorption rate is as low as 0.01%, so the insulation resistance in water is 1.5%. 5×1017ΩCm
In addition to exhibiting a high value, the mechanical strength is also superior to conventionally used polyethylene resins. If necessary, if a protective layer 7 of polyvinylidene fluoride or ethylenetetrafluoroethylene copolymer is formed as a third layer, the mechanical strength can be further increased compared to the conventional one. In other words, polyvinylidene fluoride can be used in the temperature range of -60°C to 150°C, has excellent impact resistance at low temperatures, and has a melting point of 170°C, making it easy to mold and process, and of course has a tensile strength of 400 to 520k9/Cfi. It's big. Ethylenetetrafluoroethylene copolymer has a heat resistance of 180℃
It has a high mechanical strength of 455 kg/C7 when layered.
When obtaining the same strength with a material having a large value of lf, the layer thickness can be formed thinner than that of conventional fluororesins of this type, such as trifluorochloroethylene or tetrafluoroethylene. Next, a specific example of such a winding will be described.

That is, polyamide-imide resin is baked on the copper wire 1 to a thickness of about 40 μm as a shielding layer 5, and then methylpentene resin is baked on top of this as an insulating layer 6 to a thickness of 0.25 to 0.28 μm.
A layer is formed by extrusion molding to a thickness of 0.07 to 0.0 mm, and a protective layer 7 of polyvinylidene fluoride is formed on this layer to a thickness of 0.07 to 0.0 mm.
It is manufactured by forming a coating of about 0.08TnIfL, and the total thickness of layers 5 to 7 is 0.38 to 0.40TfrJn.
It was set as the degree. The following table shows the specifications of the winding according to the above-mentioned example.

Moreover, FIG. 3 shows the application of the winding in the above-mentioned specific example. This is a diagram showing the relationship between voltage and life time. From this diagram, it can be seen that when 600V is applied, the life is over 100,000 hours.

As explained above, according to the present invention, a shielding layer of polyamide-imide resin is formed on the copper wire 1, and a shielding layer of polyamide-imide resin is formed on the copper wire 1. Since the insulating layer 6 made of methylpentene resin is laminated on the octopus shielding layer 5, it has excellent heat resistance and insulation properties in high-temperature water, as well as excellent hydrolyzability and mechanical strength, making it highly reliable. It is easy to process, the layer thickness can be reduced, and the electric motor can be made smaller and lighter.

In the above embodiment, the protective layer 7 made of polyvinylidene fluoride or ethylenetetrafluoroethylene copolymer was formed on the insulating layer 6 of methylpentene resin, but this protective layer 7 may be omitted.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional winding, Fig. 2 is a cross-sectional view showing an embodiment of a winding for a water-sealed submersible motor according to the present invention, and Fig. 3 is the relationship between applied voltage and life time of the winding. It is a figure showing an example. 1... Copper wire, 5... Shielding layer, 6...
...Insulating layer.

Claims (1)

[Claims] 1. A winding for a water-sealed submersible motor, characterized in that a shielding layer 5 of polyamide-imide resin is formed on a copper wire 1, and an insulating layer 6 of methylpentene resin is laminated on the shielding layer 5.