JPS596754A - Manufacturing method of molded motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a molded motor, in which stator windings are wound in a toroidal manner around the yoke of each slot of an annular stator core, and then integrally molded with synthetic resin. be.

When toroidal winding is applied to the yoke of each slot of the stator core, the coil end dimensions are significantly reduced compared to the conventional winding method in which the winding is pre-wound and inserted into the slot. This has the advantage that a thin motor can be obtained. However, since the windings are also set on the outer periphery of the core, it is difficult to attach a frame or bracket to the outer periphery of the core as in the past. A method is used to form a frame.

Furthermore, as a method for winding without relying on a toroidal winding machine, it is efficient to divide the iron core in the radial direction and wind the wire by winding a flyer around the yoke of each slot.

When the wire wound in this way is molded,
Since the winding is exposed from the end face of the core to the entire outer peripheral surface, the setting position of the gate becomes a problem. That is, if the resin directly injected into the exposed windings collides with it, its energy may damage or scrape off the insulation film of the windings, even causing wire breakage.

Normally, to avoid this problem, the gate position is shifted,
This prevents the injected resin from directly colliding with the windings.

FIG. 1 shows the mold structure at this time. However, when a toroidal winding is applied, the range in which the gate can be set is only a narrow range near both the upper and lower end surfaces of the molded product, as shown by g in FIG. 1, and the molding is extremely unbalanced.

That is, the resin is injected from G, flows in two paths, upper and lower as shown by the arrows, and fills the cavity formed by the lower mold 3, the center core 4, and the upper mold 5. Therefore, there is a difference in packing density between the upper housing part H1 and the lower housing part H2, resulting in a difference in dimensional accuracy between the upper and lower parts.

In FIG. 1, numeral 1 denotes an annular stator core, and numeral 2 denotes a stator winding wire wound around a yoke portion of the stator core 1 in a toroidal shape.

In view of the above points, the present invention aims to improve mold accuracy, quality, and reliability by making it possible to set the position of the gate regardless of the presence or absence of winding.

Hereinafter, a detailed explanation will be given based on examples.

FIG. 2 is a diagram showing a state in which an annular stator core 1 is divided into two parts and stator windings 2 are toroidally wound on yoke parts for each slot and molded.

Before the stator core 1 after winding is set in a mold, the outer periphery of the winding is covered with a plastic film tube 6 which has electrical insulation properties and has the property of shrinking when heated, and is heat-shrinked as shown in FIG. It is structured as follows. The width of this plastic film tube 6 after shrinkage is 1 of the stacking thickness of the iron core 1.
1. It is installed with the same width or a slightly wider width. If the thickness of each tube is thin, attach multiple tubes one on top of the other.

Thereafter, it is set together with the core 4 in the cavity 3' of the lower mold 3 and sealed with the upper mold 6 to complete the mold setting. In this way, even if G is set in the center of the core with a thickness of 11, the injected resin will hit the tube 6, so damage to the winding in that area due to resin collision can be prevented. .

In this case, the resin flows uniformly upward and downward as shown by the arrow, and therefore both the upper and lower housing parts H1 and 12 are under the same molding conditions. ≧Improvement of dimensional accuracy of the lever part and reduction of variation width It is possible to aim for

Furthermore, in the case of this embodiment in which the iron core is divided, temporary joining of the iron core is possible by the contraction of the covered tube 6, which facilitates handling and improves work efficiency when connecting the wires after winding or when connecting the Hiji line. There are also benefits to improvement.

In the embodiment, an example in which the core is divided is explained, but a structure in which the core is not divided can also have the same effect of improving dimensional accuracy.

As described above, according to the present invention, it is possible to obtain a molded product with high quality and reliability in a stator mold with a toroidal winding in which the winding is exposed on the outer periphery of the core. In some cases, the assembly work can also be streamlined.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a mold showing the relationship between gate position and resin flow in a conventional mold state, FIG. 2 is a cross-sectional view of a mold showing a mold state according to an embodiment of the present invention, and FIG. FIG. 3 is a perspective view of the stator with a heat shrink tube attached after winding is completed. 1...Stator core, 2...Stator winding, 3...Lower mold, 4...Center core, 6...
...Top mold, 6...Plastic film tube. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3!

Claims (3)

[Claims] (1) After winding the stator winding in a toroidal shape on the yoke of each slot of the annular stator core, the outer periphery of the stator winding is made of electrically insulating and heat-shrinkable plastic. After being covered with a film tube and heat-shrinked, the stator is placed in a mold that has a gate near the center of the core thickness, and synthetic resin is injected through the gate to integrate the stator core and stator windings. A method for manufacturing a molded motor. (2) After dividing the annular stator core into multiple parts and winding the stator winding in a toroidal shape on the yoke of each slot of each divided core, the divided surfaces of each divided core are brought into contact to form an annular shape. In this state, the outer periphery of the stator winding is covered with a plastic film tube that has electrical insulation and heat shrinkability and is heated and shrunk, and then the stator is gated near the center of the core thickness. 1. A method for manufacturing a molded motor, in which the stator core and stator windings are integrally molded by setting the motor in a mold having a mold and injecting synthetic resin through the gate. (3) The method for manufacturing a molded motor according to claim 2, wherein the plastic film tube is provided with a width approximately equal to the core thickness of the steel.