JPH0937501A - Stator for molded motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a coil from being exposed in a synthetic resin sheath coating surface and from being disconnected, by providing a rib, brought into contact with a stator core, in a bobbin flange part opposed to the stator core. SOLUTION: A stator of a molded motor comprises a stator semi-finish product consisting of a yoke core 1, stator core 2, coil 3 and a bobbin 4 and a synthetic resin sheath coating 5 integrally molded so as to wrap the stator semi-finish product. The yoke core 1 is provided with a plurality of radially arranged leg parts, to inset the bobbin 4, having a flange part in both ends to wind the coil 3, to each leg part. In the yoke core 1, the annular stator core 2 is fixedly press fitted so as to magnetically short-circuit a tip end of the adjacent leg parts, to provide a rib 41, brought into contact with the stator core 2, in a stator core side flange part of the bobbin 4. A rib shape, in order to facilitate press fitting work of the stator core 2, is formed into a shape of continuously decreasing a height toward the outside in a core thickness direction from a surface opposed to the stator core 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator for a molded motor having a synthetic resin outer coating formed by integral molding, which is used for driving various home appliances and for a blower fan.

[0002]

2. Description of the Related Art In recent years, molded motors have been increasingly used for motors used in home electric appliances for the purpose of reducing noise due to electromagnetic vibration of a core and protecting coils and cores against moisture.

The structure of a conventional molded motor will be described below with reference to FIGS. 7 and 8.

FIG. 7 shows a stator of a conventional mold motor, FIG. 7 (a) is a sectional view in the direction perpendicular to the core stacking thickness, and FIG. 7 (b) is a sectional view in the core stacking thickness direction.

FIG. 8 is a perspective view showing a part of a stator of a conventional molded motor before press-fitting a stator core and integrally molding a synthetic resin outer coating.

As shown in FIG. 7, the stator of the molded motor includes a yoke core 1, a stator core 2, a coil 3 and a winding frame 4.
And a semi-finished product of synthetic resin integrally molded so as to enclose the semi-finished product of the stator.

The yoke core 1 is provided with a plurality of radially arranged legs, and a winding frame 4 around which a coil 3 is wound and which has flanges at both ends is inserted into each leg. Further, an annular stator core 2 is press-fitted and fixed to the yoke core 1 so as to magnetically short-circuit the tips of adjacent legs. A certain gap is provided between the stator core 2 and the flange of the winding frame 4 so that the flange facing the stator core of the stator core 2 and the stator core of the winding frame 4 does not hit during this press-fitting work. The resin exterior coating 5 is filled during integral molding.

[0008]

In such a conventional stator of the molded motor, there is a gap between the flange portion of the winding frame 4 and the stator core 2 when the synthetic resin exterior coating 5 is integrally molded. Since the synthetic resin exterior coating 5 is filled, a large pressure is applied to the flange portion of the winding frame 4 to deform the winding frame 4, and as a result, the coil 3 is exposed on the surface of the synthetic resin exterior coating 5. The coil 3 is disconnected. There were many problems such as In particular, when a thermoplastic resin (which has advantages such as short molding time and easy post-treatment such as deburring) is used as the synthetic resin, the resin temperature is high at the time of integral molding, so that the reel becomes soft and the above problems occur. The points are noticeable.

The present invention solves the above problems, and an object of the present invention is to provide a stator of a molded motor which is of high quality and excellent in productivity.

[0010]

In order to achieve the above object, the present invention provides a rib for abutting the stator core on the flange portion of the winding frame facing the stator core.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a stator of a molded motor according to a first embodiment of the present invention, which is shown in FIG.
Is a sectional view in the direction perpendicular to the core stacking thickness, and FIG. 1B is a sectional view in the core stacking thickness direction.

FIG. 2 is a perspective view showing a part of the stator of the molded motor according to the first embodiment of the present invention, which is in a state before the synthetic resin outer covering is molded and before the stator core is press-fitted.

As shown in FIG. 1, the stator of the molded motor includes a yoke core 1, a stator core 2, a coil 3 and a winding frame 4.
And a synthetic resin outer covering 5 integrally formed so as to enclose the stator semi-finished product. The yoke core 1 is provided with a plurality of radially arranged legs, and a winding frame 4 around which a coil 3 is wound and which has flanges at both ends is inserted into each leg. Further, an annular stator core 2 is press-fitted and fixed to the yoke core 1 so as to magnetically short-circuit the ends of the adjacent legs, and a rib 41 is provided on the flange portion of the winding frame 4 on the stator core side so as to come into contact with the stator core 2. It is provided.

FIG. 3 is an enlarged perspective view of a rib portion according to the first embodiment of the present invention. The rib shape facilitates press-fitting work of the stator core 2, so that the height is higher than the surface facing the stator core in the core thickness direction. It has a shape that decreases continuously toward the outside.

FIG. 4 is an enlarged perspective view of a rib portion according to a second embodiment of the present invention, in which an end portion of the rib 41a is chamfered in order to facilitate press-fitting work of the stator core 2.

FIG. 5 is an enlarged perspective view of a rib portion according to the third embodiment of the present invention, in which the corners of the end portion of the rib 41b are rounded in order to facilitate the press-fitting work of the stator core 2.

FIG. 6 is an enlarged perspective view of a rib portion according to a fourth embodiment of the present invention. By providing the rib, the wall thickness of the bobbin collar portion becomes non-uniform, and a molding defect such as a sink mark occurs when the reel is formed. In order to prevent the occurrence of the above, a recess is provided in the center of the rib 41c. Further, the ribs may be provided at any position on the winding frame brim facing the stator core 2, but in order to facilitate the press-fitting work of the stator core 2, the ribs are not deformed by the stress caused by winding. It is preferable to arrange the inner peripheral portion in a small number.

As described above, according to the molded motor of the embodiment of the present invention, since the taper, the chamfer, etc. are provided at the ends of the winding frame ribs, the work of press-fitting the stator core 2 into the yoke core 1 is easy. Yes, stator core 2 and bobbin 4
Since the rib 41 closes a part of the gap of the flange portion, the pressure applied to the winding frame 4 when integrally molding the synthetic resin exterior coating 5 can be significantly reduced, and the deformation of the winding frame 4 can be prevented. Since the size is reduced to a level without a problem, it is possible to prevent the coil 3 from being exposed to the surface of the synthetic resin exterior coating 5 and the disconnection.

Further, since the winding frame is less likely to be deformed during the integral molding, the degree of freedom of molding conditions is increased and the molding cycle time can be set shorter, so that the productivity can be improved.

In this embodiment, the number of the yoke core legs is four, but the same effect can be obtained with a plurality of other legs.

[0022]

As is apparent from the above description, according to the present invention, by providing the rib for abutting the stator core on the flange portion of the winding frame, the pressure applied to the winding frame when integrally molding the synthetic resin outer covering is reduced. Since the deformation of the winding frame can be reduced to a level at which there is no problem, it is possible to prevent the coil from being exposed on the surface of the synthetic resin exterior coating, disconnection, and the like, and to shorten the molding cycle time.

[Brief description of drawings]

FIG. 1A is a cross-sectional view of a stator of a molded motor according to a first embodiment of the present invention in a direction perpendicular to a core stacking thickness, and FIG. 1B is a perspective view of the molded motor according to the first embodiment of the present invention. Cross section of child core stacking direction

FIG. 2 is a perspective view of the stator of the molded motor according to the first embodiment of the present invention before the synthetic resin exterior coating is formed and before the stator core is press-fitted.

FIG. 3 is an enlarged perspective view of a rib portion according to the first embodiment of the present invention.

FIG. 4 is an enlarged perspective view of a rib portion according to a second embodiment of the present invention.

FIG. 5 is an enlarged perspective view of a rib portion according to a third embodiment of the present invention.

FIG. 6 is an enlarged perspective view of a rib portion according to a fourth embodiment of the present invention.

FIG. 7A is a sectional view of a stator of a conventional molded motor in a direction perpendicular to the core stacking thickness. FIG. 7B is a sectional view of a stator of a conventional molded motor in a core stacking thickness direction.

FIG. 8 is a perspective view of a stator of a conventional molded motor before synthetic resin exterior coating molding and before stator core press-fitting.

[Explanation of symbols]

 1 yoke core 2 stator core 3 coil 4 winding frame 5 synthetic resin exterior coating 41, 41a, 41b, 41c rib

Claims (4)

[Claims] 1. A plurality of synthetic resin winding frames having flanges at both ends around which a coil is wound, and a yoke core having a plurality of radially arranged leg portions into which the winding frames are inserted. A stator half-finished product comprising an annular stator core press-fitted to the yoke core leg ends so as to magnetically short-circuit adjacent leg ends of the yoke core; and a stator semi-finished product that wraps around the stator half-finished product. A stator for a molded motor, comprising: a molded synthetic resin exterior coating; and a rib that abuts the stator core, which is provided on a flange portion of the winding frame that faces the stator core. 2. The stator of a molded motor according to claim 1, wherein the height of the rib continuously decreases from the surface facing the stator core toward the outside in the thickness direction of the stator core. 3. A chamfered end portion of the rib.
The stator of the described molded motor. 4. The stator of a molded motor according to claim 1, wherein a recess is provided in a central portion of a surface of the rib facing the stator core.