JPH0674060U - Outer rotor type induction motor - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide an outer rotor type induction motor with a ventilation structure for reducing a temperature rise around a stator winding. [Structure] A side surface of a rotor frame that supports a rotor core is positioned close to a side surface of a bracket, and a plurality of first vent holes are provided at positions on a predetermined concentric circle from the center of the side surface of the bracket, and the rotor frame faces each other. The second ventilation hole is provided at the position, and the rotation of the rotor sucks in air through the first ventilation hole of the bracket and sends it to the periphery of the stator winding inside the rotor frame to increase the temperature around the stator winding. The feature is that it is reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an outer rotor type induction motor, and more particularly to a ventilation structure for an outer rotor type induction motor.

[0002]

[Prior art]

 Conventionally, in outer rotor type induction motors, the outer circumference of the stator core is covered by a ring-shaped rotor core, and one side is shielded by the rotor frame, so the heat generated from the stator windings is internally caged. The problem is raising the temperature of. As a countermeasure against this, as shown in FIG. 4 and FIG. 5, a plurality of ventilation holes are formed along one side of the stator along the outer periphery, and a plurality of radial holes are radially formed on the outer edge of the rotor frame in order to ventilate the inside. The blades 18 are installed upright, and the air is taken in from the multiple ventilation holes provided in the bracket by the rotation of the rotor, passes between the outer periphery of the rotor and the bracket, and flows into the ventilation holes of the stator to perform internal ventilation. I have to. In this case, most of the internal air flow passes between the outer circumference of the rotor and the bracket, and the air around the stator windings remains trapped, which is effective in reducing the temperature rise in the stator windings. It wasn't a means.

[0003]

[Problems to be solved by the device]

 The present invention has been made in view of the conventional problems described above, and provides an outer rotor type induction motor that reduces the temperature rise of the stator winding by causing the internal air flow to go around the stator winding. The purpose is to do.

[0004]

[Means for Solving the Problems]

 In order to achieve the above object, a plurality of ventilation holes are formed on one side of the stator along the outer circumference, while a plurality of ventilation holes are formed concentrically with the rotor rotating shaft on the side surface of the bracket and the surface of the rotor frame which face each other. Vents were formed. In addition, a plurality of ventilation holes opened in the rotor frame have a sectional shape that is inclined toward the rotor rotation direction. Further, bent pieces that are inclined toward the rotor rotation direction are formed in the plurality of ventilation holes formed in the rotor frame.

[0005]

[Action]

 According to the above configuration, a plurality of ventilation holes are formed concentrically with the rotor rotation shaft on the side surfaces of the adjacent bracket and the surfaces of the rotor frame that face each other, and the ventilation holes of the rotor frame allow the ventilation holes of the rotor frame to pass through as the rotor rotates. Passes through the pores, draws air through the ventilation holes in the bracket, flows through the ventilation holes in the rotor frame to the inside and outside of the stator core, and the internal air flow passes through the holes in the end brackets that support the bearings on the stator side. The outside air flow is discharged from the ventilation holes of the stator to cool the stator winding and reduce the temperature rise of the stator winding. In addition, the ventilation hole of the rotor frame has a cross-sectional shape inclined toward the rotor rotation direction, so that the flow of the inflowing air can be promoted.

[0006]

【Example】

 Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a side sectional view showing the structure of the outer rotor type induction motor of the present invention, and FIG. 2 is a bottom view of the same. The stator core 2 around which the stator winding 1 is wound, the wiring board 3 and the like are made of insulating thermosetting resin 4 A plurality of ventilation holes 7 are concentrically provided along the outer periphery of the same side surface as the recessed seat 6 at the center of one side of the stator 5 integrally formed by, and the end bracket 9 supporting the bearing 8 is press-fitted into the recessed seat 6. Alternatively, a rotor frame 11 that is fixed by adhesion and supports the rotor core 10 formed in a ring shape is fixed to the rotor rotation shaft 12 so that the rotor core 10 faces the outer circumference of the stator core 2, and a recess provided in the center of the bracket 13 The bearing 8 is press-fitted into the bracket 14, the rotor core 10 is arranged so as to face the outer circumference of the stator core 2 by the bearing 8 of the bracket 13 and the bearing 8 of the stator 5, and the outer circumference of the stator 5 is press-fitted into the bracket 13. Then fixed . The upper side surface of the rotor frame 11 is arranged close to the bracket 13, and a plurality of first vent holes 14 are formed concentrically on the upper side surface of the bracket 13 in a radial pattern. A plurality of second ventilation holes 15 are formed concentrically in a radial pattern.

FIG. 3 is a cross-sectional side view of an essential part showing the relative positions of the first vent hole 14 and the second vent hole 15, and FIG. 3 (a) is an enlarged view within the circle A of FIG. 1. In FIG. 3 (a), the first ventilation hole 14 of the bracket 13 and the second ventilation hole 15 of the rotor frame 11 are placed so as to coincide with each other, and as shown in FIG. The air is sent between the rotor frame 11 and the stator 5 supporting the stator core 2 through the air holes 14 and the second air holes 15. 3 (c) and 3 (d) are sectional views taken along the line XX of FIG. 3 (a), in which the second ventilation hole 15 of the rotor frame 11 forms an angle on the upper surface in the rotation direction of the rotor 16. The lower surface has a cross-sectional shape in which the angle is reduced in the counter-rotational direction on the lower surface to accelerate the inflow of air from the first ventilation hole 14 by the rotation of the rotor 16 and to inject the inflowing air into the rotor frame 11 Between the core and the stator core 2. FIG. 3 (d) shows another embodiment, in which the second ventilation hole 15 of the rotor frame 11 is provided with a bent piece 17 bent downward or upward so as to take in air toward the rotation direction of the rotor 16. The ventilation effect around the stator winding can be improved.

[0008]

[Effect of device]

 As described above, according to the present invention, a plurality of ventilation holes are radially formed concentrically with the rotor rotation shaft on the opposite sides of the bracket and the rotor frame, so that air is also vented around the stator windings. Therefore, the temperature rise of the stator winding can be reduced.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a structure of an outer rotor type induction motor of the present invention.

FIG. 2 is a bottom view of the same.

FIG. 3 is a cross-sectional side view of essential parts showing the relative positions of a first ventilation hole and a second ventilation hole.

FIG. 4 is a side sectional view showing a structure of a conventional outer rotor type induction motor.

FIG. 5 is a bottom view of the same.

[Explanation of symbols]

 1 Stator Winding 2 Stator Core 3 Wiring Board 4 Thermosetting Resin 5 Stator 6 Recessed Seat 7 Vent Hole 8 Bearing 9 End Bracket 10 Rotor Core 11 Rotor Frame 12 Rotor Rotating Shaft 13 Bracket 14 First Vent Hole 15 Second Passage Pore 16 Rotor 17 Bending piece 18 Blade

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Yuji Soma 1116 Suenaga, Takatsu-ku, Kawasaki City Inside Fujitsu General Limited

Claims (3)

[Scope of utility model registration request] 1. A stator core around which a stator winding is wound is integrally molded of an insulating thermosetting resin to form a stator, and an end bracket holding a bearing is provided on one side of the stator. A bearing that supports the rotor rotation shaft is fixed to the center of the opposite bracket, and the rotor frame supporting the ring-shaped rotor core is fixed to the rotor rotation shaft so that the rotor core faces the outer circumference of the stator core. In the outer rotor type induction motor in which the rotor rotation shaft is supported by the bearings of the stator and the bracket, a plurality of ventilation holes are formed along the outer periphery on one side of the stator, while the side surface of the bracket and the An outer rotor type induction motor, characterized in that a plurality of vent holes are formed concentrically with the rotor rotation shaft on opposite surfaces of the rotor frame. 2. The outer rotor type induction motor according to claim 1, wherein the plurality of vent holes opened in the rotor frame have a cross-sectional shape inclined toward the rotor rotation direction. 3. The outer rotor type induction motor according to claim 1, wherein bent pieces that are inclined toward the rotor rotation direction are formed in a plurality of vent holes formed in the rotor frame.