JPS62171441A - Molding method for molded stator - Google Patents

Abstract

PURPOSE:To improve quality, by setting a concave section between the butted section of the metallic mold of a core and a section facing a space section in the metallic mold adjacent to the butted section, and by filling up the concave section with mold resin. CONSTITUTION:A core 21 organizing the laminated core of a stator has a metallic- mold-butting section 21a for a metallic mold to the corner section of a part of an end surface, and on the both sides adjacent to the section 21a, sections 21b, 21b facing a space section in the metallic mold are formed. A penetration slot 22 for inserting a rivet into is for fitting a bracket. A concave section 23 is formed between the metallic-mold-butting section 21a of the stator 21 and the sections 21b facing the space section in the metallic mold on the both sides. The core 21 with the formed concave section 23 is set in the metallic mold, and synthetic resin is injected into the space section in the metallic mold to form a molded layer 24. Then, the synthetic resin is injected also into the concave section 23 which is filled up with. So far as the molded stator manufactured in this manner is concerned, the thickness of the molded layer 24 is increased by the synthetic resin contained in the concave section 23, and crack due to the controlling resilient force is not generated, and quality can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a molded stator molding method in which the stator is covered and molded with a synthetic resin.

[Technical Background of the Invention] Conventionally, there has been a motor configured as shown in FIG. This consists of a stator 4, which is constructed by installing a coil 1 wound around a bobbin 2 to a core 3 made of a laminated iron core, and is coated and molded with a synthetic resin represented by a mold layer 5. A rotor 6 is disposed on one side, and a bracket 9.9 that supports the shaft 7 of the rotor 6 via bearings 8, 8 has mounting portions 9a, 9a exposed at a part of the end surface of the core 3. It is fastened and fixed by a rivet 11 which is applied to the exposed parts 3a and passed through the insertion hole 10 between them.

FIG. 4 shows the form of the stator 4 when molded as described above. The stator 4 is set between the lower mold 12 and the upper mold 13, and in this state, the injection machine 14 is inserted into the mold interior space. A synthetic resin is injected into the portion 15 to form the mold layer 5. At this time, both the lower mold 12 and the upper mold 13 are inserted into the insertion hole 10 of the core 3, and the lower mold 12 and the upper mold 13 are inserted into a part of the end surface. are abutted against each other to prevent the synthetic resin from flowing, thereby forming the above-mentioned exposed portions 3a, 3a, particularly on a part of the end surface of the core 3.

[Problems with the Background Art] In the case of the above-mentioned product, when the lower mold 12 and the upper mold 13 are brought into contact with a part of the end surface of the core 3, that part of the core 3 is tightened by the two full molds 12 and 13 ( In particular, since the core 3 is made of a laminated iron core, there are large variations in dimensions due to differences in lamination thickness, and in general, the mold dimensions are set according to the minimum dimension to avoid the occurrence of burrs. On the other hand, when the thickness of the core 3 is large, it is tightened more strongly, and in that state, a large elastic force for restoration is stored in the tightened part of the core 3, which is used to tighten the mold 12.
, 13, a strong pushing and spreading force acts on the mold layer 5, especially around the outer periphery of the exposed portion 3a, and as shown in FIG. There was a problem in that cracks 113,18 were generated.

[Object of the Invention] The present invention has been made to solve the above-mentioned problems, and therefore, its purpose is to prevent cracks from occurring in the mold layer due to the elastic force caused by the restoration of the core from the tightened state. figure,
It is an object of the present invention to provide a method for molding a eroded mold stator which improves quality.

[Summary of the Invention] The present invention provides a recessed portion across the mold abutting portion of the core and the adjacent portion facing the mold inner space, and fills the recessed portion with mold resin.
It is characterized in that the bonding force between the core and the mold layer is strengthened to the extent of the restoring elastic force of the core.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. First, in FIG. 2, 21 is a core made of a laminated iron core of the stator, and has a mold abutment part 21a against which a mold (not shown) is abutted against a corner part that is a part of the end face, and adjacent both sides thereof. The part 21b facing the mold inner space
, 21b. 22 is an insertion hole through which a bracket mounting glue vent is passed. Reference numeral 23 denotes a recessed portion, which is formed over the mold abutting portion 21a of the stator 21 and the portions 21b facing the mold inner space on both sides.

Then, the core 21 with the recess 23 formed therein as described above is set in a mold (not shown) in the conventional manner, and a synthetic resin is injected into the space inside the mold from an injection machine (not shown) to form the mold layer 24 shown in FIG. Form.

While facing and folding, the synthetic resin is also injected and filled into the recesses 23, respectively.

Now, according to the mold stake produced by the two-legged method, the synthetic resin filled in the recess 23 forms the mold layer 24.
The wall thickness of the mold layer 24 is increased, and for example, half of the portion 21b faces the mold inner space adjacent to the mold abutting portion 21a in the mold layer 24.

In other words, the core 21 is covered without exposing the core 21b.
It completely suppresses the restoring elastic force of
Because it increases the contact area with and strengthens the bonding force with it,
As a result, the bonding force between the core 21 and the mold layer 24 in the area where cracks have conventionally occurred is strengthened by the Ichimoto elastic force in the mold abutting portion 21a of the core 21. Thus, in the case of this embodiment, cracks due to the restoring elastic force of the core 21 no longer occur, and quality can be improved. Since cracks can be prevented in this way, there is no need to weaken the clamping force of the mold abutting portion 21a of the core 21, and therefore, even if the stacking thickness of the core 21 is the minimum, burrs will not be generated and the burrs will be removed. It is also possible to prevent problems such as the rotor coming off during operation and locking the rotor.

[Effects of the Invention] As is clear from the description below, according to the present invention, a stator whose core is made of a laminated iron core is molded into synthetic resin with a mold abutting a part of the end face of the core. , 11h, in which a recess is provided across the mold abutment part of the core and a part facing the mold inner space adjacent thereto, and the synthetic resin is applied to the recess. By filling the core, the bonding force between the core and the mold layer is strengthened beyond the original elastic force of the core. This has the excellent effect of not causing cracks due to force and improving quality.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 show one embodiment of the method of the present invention.
The figure is a perspective view of the main part of the stator core after being coated and molded. Figure 2 is a perspective view of the stator core after being coated and molded. The perspective view before molding is a longitudinal cross-sectional side view of the stator during molding. Figure 5 is a view equivalent to Figure 1. be. In the figure, 21 is the core of the stator, 21a is a mold abutting portion, 21b is a portion facing the mold inner space adjacent to the mold abutting portion, 23 is a recess, and 24 is a mold layer.

Claims (1)

[Claims] 1. A stator whose core is made of a laminated iron core is covered and molded with a synthetic resin with a mold abutting a part of the end face of the core, and the mold abutment part of the core and this 1. A method for molding a mold stator, comprising: providing a recess over a portion facing an adjacent mold inner space, and filling the recess with the synthetic resin.