JP3666295B2 - stator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in soldering workability and insulation performance, particularly for a stator of an electric motor.
[0002]
[Prior art]
In recent years, there is a growing need for compliance with safety standards in each country as well as miniaturization and high performance of electric motors. That is, while increasing the density of the winding and the space saving of the coil end portion are increasing, it is necessary to ensure and improve the insulation performance from the viewpoint of safety.
[0003]
Among them, the tendency is particularly remarkable in AC servo motors used as drive sources for robots, NC machine tools, and semiconductor manufacturing apparatuses. In order to satisfy these requirements, the resin member used is required to have an extremely thin wall molding, high insulation performance, and high flame retardant grade.
[0004]
The configuration of a conventional stator of an electric motor will be described below with reference to FIGS.
[0005]
Reference numeral 1 denotes a laminated iron core divided and laminated in units of pole teeth, 2 denotes a coil wound around the laminated iron core 1, 3 denotes an insulator for electrically insulating the laminated iron core 1 and the coil 2, and the upper and lower sides of the laminated iron core 1 They are arranged on both end faces, and are hereinafter referred to as end insulators. Here, in order to achieve higher density of the winding and space saving of the coil end portion, polyamide resin such as 66 nylon, which can be formed into an extremely thin wall, is frequently used as the material of the end insulator 3. Reference numeral 4 denotes two terminal pins fixed to one of the two end insulators 3. The winding start portion and the winding end portion of the wound coil 2 are mechanically wound and then soldered, The tooth unit body 5 is configured. Although not shown, in order to electrically insulate the coil 2 and the laminated iron core body 1, a film-like insulator is disposed between the slot side surface portion of the laminated iron core body 1 and the coil 2.
[0006]
As shown in FIG. 3, the finished stator product has a laminated core assembly 21 in which a predetermined number of pole tooth units are connected in a ring shape, and through holes that penetrate all terminal pins 4 arranged in each pole tooth unit. The multilayer wiring board 22 is provided, and the terminal pins 4 and the through hole portions of the multilayer wiring board 22 are soldered to form a predetermined circuit.
[0007]
FIG. 4 shows a manufacturing process of a conventional stator of an electric motor. 31 is a laminated core process for obtaining a laminated core body divided and laminated in units of pole teeth, 32 is an insulating process for attaching an insulating material that insulates the laminated core and the coil to the laminated core body, and 33 is a laminated core after completion of the insulating process 32. A winding process for winding a coil around the body, 34 is a soldering process for winding the coil at the beginning and end of winding after the completion of the winding process 33 and dip soldering to the terminal pin 4, and 35 is obtained in the soldering process 34. A joining step 36 for joining the laminated cores in a ring shape is a wiring step for connecting to a predetermined circuit using the terminal pins 4 of the laminated core 1 obtained in the joining step 35 and the multilayer wiring board 22.
[0008]
[Problems to be solved by the invention]
However, in the above conventional configuration, in the pole tooth unit body, the end insulator is thermally deformed due to heat conducted through the terminal pin in the soldering process at both ends of the coil at the beginning and end of winding, and the terminal pin comes off. Depending on the immersion depth during dip soldering, the end insulator melted, and at the same time, the solder adhered to the surface of the end insulator.
[0009]
Therefore, it is necessary to re-fix the terminal pin that has been removed in place, or to remove the adhered solder in order to ensure the insulation distance and maintain the insulation resistance, so that the manufacturing process is divided and the work efficiency is significantly reduced. Cost increases.
[0010]
In addition, resin materials are required to have flame resistance in order to comply with safety standards, but in general, the addition of flame retardants and flame retardant aids decreases the heat resistance. Will occur. For motors that require miniaturization, glass-reinforced polyamide resins that can be molded extremely thinly are often used, but they are composed of amide groups that are polymerized by the bond of an amine and an acid. In particular, a decrease in insulation resistance is inevitable in a high humidity environment.
[0011]
Furthermore, after connecting a predetermined number of pole tooth units in a ring shape, when connecting each coil using a multilayer wiring board, a solder ball may adhere to the conductive through hole or auxiliary through hole. As in the solder bonding process, the manufacturing process is divided to ensure the insulation resistance and the insulation distance, the work efficiency is lowered, and the cost is increased.
[0012]
The present invention solves such a conventional problem, and ensures flame retardancy, insulation resistance and insulation distance, maintains insulation resistance even in a high humidity environment, and is suitable for an automatic assembly process with high work efficiency. An object of the present invention is to provide a stator for an electric motor.
[0013]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a laminated iron core that is divided and laminated in units of pole teeth, a coil that is wound around a pole tooth portion of the laminated iron core, and the coil is electrically insulated from the laminated iron core. A laminated iron core comprising: an insulator in units of pole teeth; and two terminal pins provided for each pole tooth portion of the insulator, wherein the coil winding start portion and winding end portion are soldered to the two terminal pins, respectively. And a multilayer wiring board having a through-hole portion through which the terminal pin penetrates and the coil is soldered, and the end insulator is made of a polyamide resin of aromatic nylon and glass fiber. It is a resin molded product comprising a flame retardant and a flame retardant aid. Due to the high-density crystal structure of the aromatic nylon, the chemical resistance is enhanced and it does not react with the solder flux, so that no solder adheres. Further, the heat resistance is improved as a characteristic of the aromatic component, and it is suitable for the dip soldering process. That is, heat conduction to the end insulator is regulated by heat of vaporization and vapor of the flux at the time of dip soldering, and thermal deformation and melting are less likely to occur, so that terminal pins can be prevented from being detached and solder from being attached. Furthermore, since the number of amide groups to which water molecules are intermolecularly bonded is small, the water absorption is low, and the insulation resistance can be maintained high even in a high humidity environment.
[0014]
Further, in the multilayer wiring board used for connecting the coils of each pole tooth unit body, through holes other than those for penetrating the terminal pins are silk-printed from above the resist film. The inside diameter of the conduction through hole or auxiliary through hole is frequently 0.8 mm to 1.5 mm. However, by silk printing on the resist treatment, the surface opening of the through hole is almost blocked, and the solder ball Adhesion can be prevented.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
In order to solve the above-described problems, the present invention provides a laminated iron core that is divided and laminated in units of pole teeth, a coil that is wound around a pole tooth portion of the laminated iron core, and the coil that is electrically connected to the laminated iron core. An end insulator in units of pole teeth to be insulated and two terminal pins provided for each pole tooth portion of the end insulator are provided, and a winding start portion and a winding end portion of the coil are soldered to the two terminal pins, respectively. A stator in which laminated cores are joined in an annular shape, the stator further comprising a multilayer wiring board having a through-hole portion that penetrates the terminal pins and solders the coil, and the end insulator is made of aromatic nylon and glass fiber. It is a stator characterized by being a resin molded product comprising a flame retardant and a flame retardant aid.
[0016]
In this way, when the end insulator is a resin molded article made of polyamide resin aromatic nylon, glass fiber, flame retardant, and flame retardant aid, the high density of the aromatic nylon is maintained while maintaining flame retardancy. The crystal structure increases chemical resistance and does not react with the solder flux so that the solder does not adhere. In addition, the aromatic component is characterized by heat resistance, and it is difficult for thermal deformation and melting of the component itself to occur, and it is possible to prevent terminal pins from being detached and solder from being attached due to dip soldering. Furthermore, since aromatic nylon has a small number of amide groups in which water molecules are intermolecularly bonded, the water absorption is low, and the insulation resistance can be maintained high.
[0017]
Further, according to the present invention, a terminal pin is passed through a through hole portion of a multilayer wiring board, and the through hole portion and the terminal pin are soldered.
[0018]
In the present invention, the through hole portion other than the through hole portion that penetrates the terminal pin is covered with an insulator.
[0019]
Further, in the present invention, the insulator is silk-printed on the resist film. In this way, in the multilayer wiring board used for connecting the coils of each pole tooth unit, the through-hole part other than the terminal pin penetration is silk-printed from above the resist film, and the surface opening of the through-hole is almost silky. It will be blocked. Due to this effect, it has an action that solder adhesion called solder balls can be prevented.
[0020]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0021]
(Example 1)
As described above, the structure of this embodiment is almost the same as the conventional example, and the material structure of the end insulator 3 is different from that of the conventional example. Aromatic nylon is used as the polyamide resin, and the glass reinforcing material, flame retardant and flame retardant aid are used. Is included. The conventional 66 nylon is a polymer of hexamethylene diamine and adipic acid, whereas the aromatic nylon of this example is a polymer of hexamethylene diamine and terephthalic acid, and a polymer of amine isomer and terephthalic acid. It consists of. The heat resistance is improved by the action of terephthalic acid, and thermal deformation and melting are less likely to occur in the solder bonding process. Furthermore, because the molecular structure has a very high crystal structure, the chemical resistance becomes high and it does not react with the solder flux, so that the solder does not adhere to the end insulator due to the heat of vaporization and the vapor of the flux during dip soldering. The amount of heat conduction is restricted, thermal deformation and melting are less likely to occur, terminal pins can be removed and solder can be prevented from being attached, and this is suitable for the dip soldering process. In addition, since aromatic nylon has a small number of amide groups to which water molecules are intermolecularly bonded, the water absorption is low, and the insulation resistance can be kept high.
[0022]
FIG. 5 shows a basic characteristic comparison table of various polyamide resins. Glass-reinforced 66 nylon has a volume resistivity that is an order of magnitude lower than aromatic nylon, and a flame retardant grade 66 nylon that is an order of magnitude lower. Comparing the water absorption rate when absolutely dry, flame retardant grade 66 nylon is twice that of aromatic nylon, and there is anxiety about insulation resistance in a high humidity environment. The same applies to flame retardant grade 46 nylon.
[0023]
FIG. 6 shows a comparison table of resistivity of various polyamide resins in a high humidity environment. It can be seen that aromatic nylon is most advantageous in terms of insulation resistance because aromatic nylon is most stable in both volume resistivity and surface resistivity.
[0024]
(Example 2)
The configuration of Example 2 relates to the structure of the multilayer wiring board in FIG. FIG. 7 is a plan view of the multilayer wiring board in FIG. 3. 61 to 63 are through holes for soldering three-phase lead wires, and 64A to 87A are through holes for penetrating the terminal pins. There are 24, and 64B to 87B are 24 auxiliary through holes of through holes for penetrating terminal pins. FIG. 8 shows a partial cross-sectional view in the vicinity of 64A and 64B. In FIG. 8, 71 is a copper foil pattern, 72 is a resist, and 73 is silk. Conventionally, since there was no silk 73, a solder ball might adhere on the resist of the auxiliary through hole 64. Since this solder ball shortened the insulation distance or moved on the multilayer wiring board and caused a breakdown voltage failure, man-hours for removal were required. In the present invention, since the surface of the auxiliary through hole is covered with the silk 73, adhesion of the solder ball is eliminated.
[0025]
【The invention's effect】
As is apparent from the above embodiments, according to the present invention, the end insulator used for the stator of the electric motor has a high-density crystal structure of aromatic nylon, which increases chemical resistance and does not react with the solder flux. The adhesion of disappears. Further, the heat resistance is improved as a characteristic of the aromatic component, and it is suitable for the dip soldering process. That is, the amount of heat conduction to the end insulator is regulated by the heat of vaporization and vaporization of the solder flux during dip soldering, so that thermal deformation and melting are less likely to occur and terminal pins can be removed and solder can be prevented from adhering. Furthermore, since the number of amide groups to which water molecules are intermolecularly bonded is small, the water absorption is low, and the insulation resistance can be kept high.
[0026]
Also, electrodeposition in the stator of motivation, using a multi-layer wiring board to the coil connection, measure the number of steps reduced, conduction through-holes or coil connection that is about 1.5mm inner diameter of the auxiliary through hole from 0.8mm By performing silk printing on the resist processing of the multilayer wiring board, the surface opening of the through hole is almost blocked and the solder ball is prevented from adhering.
[0027]
Furthermore, according to the present invention, it is possible to obtain a stator of an electric motor suitable for an automatic assembly process with high work efficiency while ensuring flame resistance, dielectric strength and insulation distance, maintaining insulation resistance even in a high humidity environment. Needless to say, you can.
[Brief description of the drawings]
1 is a front view of a partial configuration diagram of a stator of an electric motor. FIG. 2 is a right side view of a partial configuration diagram of a stator of an electric motor. FIG. 3 is a cross-sectional view of a stator of an electric motor. FIG. 5 shows a comparison table of basic characteristics of various polyamide resins. FIG. 6 shows a comparison table of resistivity of various polyamide resins in a high humidity environment. FIG. 7 shows an example of the present invention. Plan view of the multilayer wiring board shown [FIG. 8] Partial sectional view of the multilayer wiring board [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Laminated iron core body 2 Coil 3 End insulator 4 Terminal pin 5 Polar tooth unit body 21 Laminated iron core assembly 22 Multilayer wiring board 64A Terminal pin through-hole 64B Auxiliary through-hole 71 Copper foil pattern 72 Resist 73 Silk

Claims (2)

A laminated iron core that is divided and laminated in units of pole teeth, a coil that is wound around a pole tooth portion of the laminated core, an insulator in units of pole teeth that electrically insulates the coil from the laminated iron core, and the insulator Two stator pins provided for each pole tooth portion, and a stator in which a laminated iron core body in which a winding start portion and a winding end portion of the coil are respectively solder-connected to the two terminal pins is annularly joined, It further comprises a multilayer wiring board having a through-hole portion that penetrates the terminal pin and solders the coil, and the insulator is a resin molded product made of aromatic nylon, glass fiber, a flame retardant, and a flame retardant aid. Stator characterized by. The stator of covered claim 1, wherein silk printed on the resist film or the resist film is an insulator through hole portion other than the through hole through which the terminal pins of the multi-layer wiring board.

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