JP2001230113A - Heat-resistant insulated coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-resistant insulated coil which can be used at a higher temperature than an organic polymer electric wire and capable of dispensing with burning that is usually carried out after winding an electric wire into a coil. SOLUTION: A heat-resistant insulated coil is formed through such a manner in which a heat-resistant insulated electric wire 20 is wound as many turns as prescribed for the formation of a coil, and the coil is protected by taping it with an inorganic insulating thin sheet material. The heat-resistant insulated electric wire 20 is composed of a lead wire 21 and an insulation coating layer 22 formed around the lead wire 21. The insulation coating layer 22 is of two- layered structure composed of a ceramic insulation coating layer 22a formed around the lead wire 21 and an inorganic filler-free heat-resistant organic insulation layer 22b formed covering the outer surface of the ceramic insulation coating layer 22a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a heat-resistant insulating coil which can be used at high temperatures.

[0002]

2. Description of the Related Art Conventionally, as a heat-resistant insulating coil, a coil using an organic polymer wire and a coil using an inorganic polymer wire have been used. The organic polymer electric wire is used when the heat resistance temperature is relatively low, and is formed by forming an insulating coating of an organic polymer such as polyester, formal, polyurethane, polyamide imide, or polyimide around the conductor.

On the other hand, an inorganic polymer electric wire is used when the heat resistance temperature is relatively high, and a coating containing an inorganic polymer such as polyborosiloxane as a main component is applied around the conductor and baked to form an insulating film. It is composed. However, if an inorganic polymer is directly applied and baked to form an insulating film, the flexibility becomes low and coil winding is difficult, so the baking temperature of the inorganic polymer is lowered to form an organic resin layer on the surface, A method of firing after coil winding to thermally decompose and remove organic components has been adopted.

[0004]

However, the temperature of an organic polymer electric wire is about 240 ° C. even when a polyimide having the highest heat-resistant temperature is used as a film. Therefore, when a coil using an organic polymer electric wire is used, if the heat generation temperature of the conductor or the surrounding temperature becomes higher, it is necessary to provide a cooling device, which increases the cost and the occupied space. There is a problem that it becomes larger.

On the other hand, the inorganic polymer electric wire has a high heat-resistant temperature of 400 ° C. or higher, but requires a firing step as described above, so that the working time is lengthened and the cost is increased (problem). There is.

The present invention has been made in view of the above-mentioned problems of the prior art, and can be used at a higher temperature than an organic polymer electric wire, and does not require firing after coil winding of the electric wire. It is an object to provide an insulated coil.

[0007]

SUMMARY OF THE INVENTION A heat-resistant insulating coil according to the present invention has been made in order to solve the above-mentioned problems. According to the first aspect of the present invention, a heat-resistant insulating coil having an insulating coating layer formed around a conductive wire is provided. In a heat-resistant insulating coil formed by winding an insulated wire, the insulating coating layer is made of a ceramic insulating coating layer provided around a conductive wire and a heat-resistant insulating material containing no inorganic filler formed around the ceramic insulating coating layer. It has a two-layer structure including an organic insulating layer.

By forming the insulating coating layer into a two-layer structure as described above, the thickness of the ceramic insulating coating layer is made thinner in consideration of heat resistance while maintaining insulation, as compared with the case where the inorganic polymer coating layer is used alone. be able to. In addition, for the heat-resistant organic insulating layer, the ceramic insulating coating layer provided between the conductive wire and the conductive wire serves as a heat insulating material. Therefore, even if the temperature of the conductive wire becomes higher than the heat-resistant temperature, thermal decomposition can be avoided.

Further, in the invention according to claim 2, the heat-resistant organic insulating layer is formed of, for example, polyimide.

According to the third aspect of the present invention, the heat-resistant insulated wire wound with the coil is covered with an inorganic insulating thin material,
It was configured to be fixed to the yoke using an inorganic varnish.

Further, according to the invention described in claim 4, the lead wire connected to a predetermined portion of the heat-resistant insulated wire is a heat-resistant lead wire.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a heat-resistant insulated wire used in a heat-resistant insulated coil according to one embodiment of the present invention. FIG. 2 is a perspective view showing a heat-resistant insulated coil 10 according to one embodiment of the present invention. FIG. 2 is a sectional view showing a state in which the heat-resistant insulating coil 10 is fixed to a yoke 15.

As shown in FIG. 2 and FIG. 3, the heat-resistant insulated coil 10 of the present embodiment is formed by winding a heat-resistant insulated wire 20 in a predetermined number of turns and then taping and protecting with an inorganic insulating thin sheet material 30. Have been. In this state, the electromagnet is formed by impregnating the inorganic varnish 31 and fixing it to the yoke 15. This electromagnet is arranged, for example, in the middle of a high-temperature steel sheet conveying process in a steel sheet production factory, is used for vibration damping of the steel sheet, and has an attractive force by the electromagnet based on a detection result of a position sensor (not shown). It is controlled. Note that lead wires 50 are connected to both ends of the heat-resistant insulated wire 20 via connection portions 40.

Hereinafter, each part of the heat-resistant insulating coil 10 will be described. The heat-resistant insulated wire 20 includes a conductor 21 and an insulating coating layer 22 formed around the conductor 21 as shown in FIG. Also,
The insulating coating layer 22 includes a ceramic insulating coating layer 22 a provided around the conductive wire 21 and a ceramic insulating coating layer 2.
This is a two-layer structure composed of a heat-resistant organic insulating layer 22b containing no inorganic filler and formed on the outer periphery of 2a.

In order to maintain insulation, the insulating coating layer 22 needs to have a predetermined thickness. However, it is very difficult to secure the insulation properties of the inorganic polymer layer alone and the flexibility required for coil winding. Therefore, by forming the insulating coating layer 22 into a two-layer structure as described above, the insulating coating layer 22 can have both an insulating function and a heat-resistant function. It can be thinner than used in

The ceramic insulating coating layer 22a provided between the heat-resistant organic insulating layer 22b and the conductive wire 21 serves as a heat insulating material to prevent heat generated from the conductive wire 21 from being transmitted to the heat-resistant organic insulating layer 22b. Even if the temperature of the conductive wire 21 becomes higher than the heat resistant temperature, thermal decomposition of the heat resistant organic insulating layer 22b can be avoided.

The conductor 21 is desirably a heat-resistant copper-based composite conductor such as nickel-plated copper, nickel-clad copper and stainless-steel-clad copper. Preferably, plated copper is used. The ceramic insulating coating layer 22a includes a resin made of one or more kinds selected from inorganic polymers such as polyborosiloxane, polycarbosilane, polysilastyrene, polysilazane, polytitanocarbosilane, and organosiloxane. A ceramic material in which an inorganic filler is dissolved or dispersed in a solvent is used.

After a ceramic material is applied and baked around the conductor 21 to form a ceramic insulating coating layer 22a, a heat-resistant organic insulating layer 22b is formed. As the heat-resistant organic insulating layer 22b, for example, polyimide, polyamideimide, etc. may be mentioned, but polyimide having higher heat resistance is preferable. The heat-resistant temperature of the polyimide is about 240 ° C. as described above. However, since the ceramic insulating coating layer 22a has a heat insulating effect, the maximum temperature of the conductive wire 21 is 30 ° C.
Even when the temperature rises to about 0 ° C., thermal decomposition of the heat-resistant organic insulating layer 22b can be prevented.

After the heat-resistant insulated wire 20 is wound with a coil, it is covered with an inorganic insulating thin sheet material 30 and impregnated with an inorganic varnish 31 so that the whole is fixed to the yoke 15. As the inorganic insulating thin material 30, it is desirable to use glass fiber, silica fiber, alumina fiber, or mica tape alone or in combination, and glass fiber is preferable in consideration of economy and impregnation of inorganic varnish. As the inorganic varnish 31, a varnish in which one or a plurality of oxide ceramics such as magnesium oxide, alumina, zirconium oxide, calcium oxide, boron oxide, silica, mica, and talc are mixed is used.

After fixing with the inorganic varnish 31, the lead wire 50 is connected to both ends of the heat-resistant insulated wire 20 via the connecting portion 40. Lead wire 50 connected to heat-resistant insulated wire 20
Is a heat-resistant lead wire. The conductor of the lead wire is preferably nickel-plated copper having high heat resistance. Also, since a considerable load may be applied to the lead wire, a flexible stranded wire is preferably used. As the insulating coating layer of the lead wire 50, for example, a Teflon coating having heat resistance can be used.

The connecting portion 40 between the heat-resistant insulated wire 20 and the lead wire 50 is formed, for example, by the method described in Japanese Patent Application Laid-Open No. Hei 9-111426. That is, the heat-resistant insulated wire 20
The coating on each end of the wire and the lead wire 50 is removed, the exposed conductor is inserted from both ends of the metal tube, the ends are brought together, and the metal tube is deformed by pressing it from the side, and the end of each wire is removed. Fix to metal tube. After that, the entire connection portion 40 is plated with a metal having excellent oxidation resistance such as nickel. Through the above steps, an electromagnet using the heat-resistant insulating coil 10 is completed.

[0022]

As described above, the heat-resistant insulating coil of the present invention has the following excellent effects. (1) First, the basic structure of the present invention according to claim 1 has the following effects. By making the insulating coating layer a two-layer structure of a ceramic insulating coating layer and a heat-resistant organic insulating layer, the thickness of the ceramic insulating coating layer can be maintained more than that of the inorganic polymer coating layer alone while maintaining insulation and heat resistance. Can be thin. Therefore, it is possible to omit the firing step after winding the coil which was necessary when using the conventional inorganic polymer electric wire,
Workability can be improved and work time can be reduced. In addition, for the heat-resistant organic insulating layer, the ceramic insulating coating layer provided between the conductive wire and the conductive wire serves as a heat insulating material. Therefore, even if the temperature of the conductive wire becomes higher than the heat-resistant temperature, thermal decomposition can be avoided. Therefore, even when used at a temperature higher than the heat-resistant temperature of the heat-resistant organic insulating layer, a cooling device is not required, and the cost can be reduced and the occupied space can be reduced as compared with a conventional coil requiring a cooling device. .

Next, according to the inventions of the second to fourth aspects, the following supplementary effects can be obtained in addition to the effects of the first aspect. (2) As described in claim 2, when the heat-resistant organic insulating layer is formed of polyimide, the temperature is 240 ° C.
High heat resistance. (3) When the heat-resistant insulated wire wound with the coil is covered with an inorganic insulating thin material and fixed to the yoke with an inorganic varnish as described in claim 3, the heat-resistant insulated wire is maintained in an appropriate insulating state. Fixation to the yoke becomes possible. (4) When the lead wire connected to a predetermined portion of the heat-resistant insulated wire is a heat-resistant lead wire, the present invention including the lead wire is implemented. Heat resistance of the insulated wire can be maintained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a heat-resistant insulated wire used for a heat-resistant insulated coil according to one embodiment of the present invention.

FIG. 2 is a perspective view showing a heat-resistant insulating coil according to the embodiment.

FIG. 3 is a cross-sectional view showing a state where the heat-resistant insulating coil of FIG. 2 is fixed to a yoke.

[Explanation of symbols]

 10: Heat-resistant insulated coil 15: Yoke 20: Heat-resistant insulated wire 30: Insulated thin sheet material 31: Inorganic varnish 40: Connection part 50: Lead wire

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5E044 CA01 CB10 5H604 AA02 AA08 DA01 DA04 DA06 DA07 DA21 DA22 DA24 DB25 PB01 PB03

Claims (4)

[Claims] 1. A heat-resistant insulating coil formed by winding a heat-resistant insulated wire having an insulating coating layer formed around a conductive wire, wherein the insulating coating layer comprises a ceramic insulating coating layer provided around the conductive wire. And a heat-resistant organic insulating layer not containing an inorganic filler formed on the outer periphery of the ceramic insulating coating layer. 2. The heat-resistant insulating coil according to claim 1, wherein the heat-resistant organic insulating layer is formed of polyimide. 3. The heat-resistant insulated coil according to claim 1, wherein the heat-resistant insulated wire wound with the coil is covered with an inorganic insulating thin sheet material and fixed to the yoke using an inorganic varnish. 4. The heat-resistant insulated coil according to claim 1, wherein a lead wire connected to a predetermined portion of the heat-resistant insulated wire is a heat-resistant lead wire.