JPS5833945A - Stator core for inner rotor type motor - Google Patents

Abstract

PURPOSE:To readily respond to the many kind and small quantity production and to improve the degree of freedom of the motor characteristics by composing with an annula teeth unit and an outer wheel unit forming a magnetic path and forming arbitrarily discontinuous slits at the thin plate between the teeth. CONSTITUTION:A stator core is divided into an outer wheel unit 10 and teeth unit 20, and the unit 10 is formed of an annular magnetic path 11 and a recess 12 for engaging the teeth 21 after winding. On the other hand, the teeth unit 20 is composed of teeth 21 radially projected in response to the number of poles, slots 22 interposed between the teeth, an annular thin plate 23 for coupling the teeth group inside, and slits 24 provided through the plate 23 at the center between the teeth discontinuously in the thicknesswise direction of the stator. The slots of the unit 20 are opened toward the outer periphery, and the winding method enables to employ a flier winding type.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stator core for an inner rotor type electric motor.

The stator core of conventional inner rotor type electric motors has a shape in which the teeth protrude in the direction of the shaft center, so a method called the insert method is generally used for winding.
The wire wound around the formwork is inserted into a predetermined slot of the systator using a jig called a blade.

However, when winding wires using this insert method, it is necessary to prepare expensive blade jigs for each compatible model when producing a large number of models in small quantities, and the task of changing models is complicated.

Furthermore, for the purpose of smooth insertion, the outer circumference of the wire must be considerably longer than that of the slot of the stator, so that both ends of the stator are exposed after insertion.

As described above, winding using the insert method requires a large amount of manpower to process the wire even after inserting the wire, and automation of the process is also unsuitable for high-mix, low-volume production.

Further, the amount of wire used is more than necessary, and there are problems such as not only material loss but also current heat generation.

Fig. 1 shows the structure of a conventional stator core, in which an outer ring part 1 forming a magnetic path is integrally formed with teeth parts 2 arranged according to the number of poles of the motor, and teeth protruding in the direction of the shaft center. A slot 3 into which the winding is inserted is formed in a space surrounded by the outer ring portion 1 and the slot 3 between each tooth.
A slit 4 is formed which communicates with the.

One end of the wire will be inserted into the slot 3 through the slit 4. The width t of this slit 4 has a great influence on the characteristics of the electric motor, but there is little room to go into it since the main premise is to ensure the minimum dimension that allows insertion of the wire ring as an issue before considering the characteristics.

The present invention eliminates the above-mentioned conventional drawbacks by devising the shape of the stator core.The present invention will be described below with reference to FIG. 2. As shown in the figure, the stator core of the present invention is divided into an outer ring body 1o and a tooth body 2o, and the outer ring body 1o is composed of an annular magnetic path 11 and a recess 12 into which the teeth 21 after winding are fitted. On the other hand, the teeth body 2o includes teeth 21 that protrude radially according to the number of poles of the electric motor, slots 22 held by the teeth 21, an annular thin plate part 23 that connects the teeth groups on the inside, and a space between each tooth. The thickness of the stator is located at the center and penetrates the thin plate portion 23.
The slits 24 are provided discontinuously in the direction. 25 is a discontinuous point.

Since each slot 22 of the seat body 20 is open at the outer periphery unlike the conventional example, the flyer winding method can be used as the winding method.

Compared to the insert method, this method can be considerably covered by consideration in the design of the winding wiring, but some problems remain in terms of the wire area factor.

However, the flyer winding method has advantages beyond this point.

In other words, since the windings are directly wound, there is no excess wire protruding from both ends of the stator than necessary, the finish of the windings is tight and there is little wire breakage, and the productivity is relatively high. It is easy to automate, etc.

This reduces the number of required wires and current heat generation, greatly simplifies the wire processing process compared to the insert method, and is also effective in downsizing the electric motor.

The slits 24 are provided long enough in the thickness direction of the stator to maintain the minimum necessary strength for the subsequent process for the entire tooth portion. The discontinuous points 26 of the slits 24 exist so that the shape of the entire teeth body can be maintained. Due to the existence of this discontinuous point 26, the electric motor is slightly different, but unlike the insert method, the width of the slit 24 can be changed freely in consideration of characteristics.
There is a large degree of freedom in design, and there is room for further improvement in characteristics.

As described above, according to the present invention, the flyer winding method is possible, it can easily cope with small-volume production of many models, and it has excellent effects such as a high degree of freedom in motor characteristics.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a part of the stator core of a conventional inner rotor type electric motor, and FIG. 2 is an exploded perspective view of a part of the stator core of the present invention. 10... Outer ring body, 11... Magnetic path, 2o
... Teeth body, 21 ... Teeth, 22 ... Slot, 23 ... Thin plate part, 24 ... Slit, 26 ... ...discontinuity point. 211th

Claims (1)

[Claims] It is composed of an annular tooth body to which a winding wire having teeth corresponding to the number of poles of the electric motor is applied, and an outer ring body that combines with this tooth body to form a magnetic path, and the space between the teeth of the tooth body is A stator core for an inner rotor type electric motor, in which a thin plate part is provided with slits having arbitrary discontinuity in the thickness direction of the stator.