JPH0229800Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention is a method for attaching a stator core with a stator winding wound around the salient pole part to a motor case, and also attaching a stator core to a motor case that corresponds to the end of the stator winding. This invention relates to a small motor in which an insulating plate is provided on the inner end surface of the motor.

(B) Prior art As disclosed in Japanese Utility Model Application No. 50-43806, this type of conventional device has an insulating plate disposed on the inner end surface of the motor case facing the end of the stator windings, which is connected to the bearing. The oil cap can be installed and fixed with the oil cap, or it can be press-fitted into the inner end surface. Therefore, for those that utilize an oil cap, the type of bearing used must be specified and a special mounting member such as an oil cap is required. In addition, in the case where an insulating plate is press-fitted into the inner end surface, shrinkage or expansion due to vibration of the motor case or temperature change of the insulating plate that occurs when the small motor is operated,
The installation state of the insulating plate may change, causing it to rise inside the motor case and come into contact with the rotor, resulting in poor rotation or sliding noise. In particular, if inexpensive fiber or thermoplastic resin is used as the insulating plate, these materials expand and contract significantly due to temperature changes. The size of the insulating plate is reduced and the inner diameter of the insulating plate is approximately equal to the inner diameter of the stator core, and the insulating plate is attached with an adhesive. However, in this case as well, due to vibration of the motor case or expansion and contraction of the insulating plate due to temperature changes, the insulating plate rises from the inner end surface of the motor case, causing the above-mentioned problem.

(c) Problems to be Solved by the Invention The present invention has been devised in view of these points, and an object of the invention is to provide a small motor in which lifting of the insulating plate is prevented.

(d) Means for Solving the Problems The small motor according to the present invention has a stator core with stator windings wound around the salient poles attached to a motor case, and a motor case that opposes the ends of the stator windings. A small motor having an insulating plate disposed on the inner end surface of the motor, characterized in that a magnetic bridging piece attached between adjacent salient pole parts is elongated so as to be close to the insulating plate. .

(E) Effect In the above means, since the magnetic bridging piece extends close to the insulating plate, even if the insulating plate stretches due to temperature changes and tries to lift up from the inner end surface of the motor case, the magnetic bridging piece The tips of the tabs prevent them from floating up.

(F) Embodiment An embodiment in which a small motor according to the present invention is applied to a cooling fan device for office automation equipment will be described with reference to the drawings. Figure 2 is a perspective view of the cooling fan device; Figure 3 is a perspective view of the cooling fan device;
The figure shows the same cross section. In these drawings, a fan casing 1 is integrally formed with a shallow dish-shaped motor case 3 via a plurality of support legs 2, for example, by die casting of aluminum.

A bearing holding sleeve 4 is insert-molded in the center of the motor case 3, and a pair of bearings 5, 5 are mounted within this sleeve.
In addition, a stator core 6 is provided on the inner peripheral surface of the motor case 3.
is attached by press-fitting or adhesive.

This stator core 6 has a pair of salient pole parts 7, as is clear from the front view of the stator shown in FIG. 4 and the exploded perspective view of the stator, insulating plate, and motor case shown in FIG. However, a stator winding 8 is wound in advance around each salient pole portion, and a shaded coil (not shown) is also installed. Insulating frame portions 9 are formed on both end surfaces of the stator core 6 and on the inner surface of the slot by outsert molding of resin. This insulating frame portion 9 is integrally provided with a terminal portion 10. Furthermore, a magnetic bridging piece 11 is press-fitted between the ends of the adjacent salient pole parts 7, 7 of the stator core 6 to improve magnetic properties, and the length of this magnetic bridging piece is a feature of the present invention. This point will be discussed later.

Rotating shaft 1 rotatably supported by a pair of bearings 5, 5
An end plate 13 is fixed to 2, and a cylindrical rotor 14 is fixed to this end plate. This rotor is a squirrel-cage rotor consisting of a rotor core 15 and a secondary conductor 16 made of aluminum die-cast, and together with the stator constitutes an induction motor. Also, the rotor 14
A fan 17 is attached around the .

Next, 18 is an insulating plate made of fiber or thermoplastic resin, whose outer diameter is smaller than the outer diameter of the stator core 6 and whose inner diameter is approximately equal to the inner diameter of the stator core 6. The end 19 is attached to the inner end surface 20 of the opposing motor case 3 to provide insulation between the stator winding end 19 and the inner end surface 20.

As is clear from FIG. 1, which is a sectional view of the motor case 3 to which the stator core 6 is attached, the magnetic bridging piece 11 is longer than the thickness of the stator core 6, and its lower end 21 is on the inner end surface. The insulating plate 18 attached to the insulating plate 20 is located close to the insulating plate 18 . Normally, the magnetic bridging piece 11a used in an electric motor is as shown in FIG.
When using a magnetic bridging piece 11a having a size that is approximately equal to the stacking thickness length of the stator core 6a, the insulating plate 18a is attached to the inner end surface 2 of the motor case 3a as shown in the figure.
Even when it floats up from 0a, it cannot be prevented from floating up. However, when the magnetic bridge piece 11 is made close to the insulating plate 18 as shown in FIG. It is possible to prevent it from rising above 20.

(g) Effects of the invention The small motor according to the invention has a stator core with a stator winding wound around the salient pole part attached to the motor case, and a stator core with a stator winding wound on the inner end face of the motor case opposite to the stator winding end. This is a small motor provided with an insulating plate, and is characterized in that the magnetic bridging piece attached between adjacent salient pole parts is elongated so as to be close to the insulating plate. Even if the insulating plate tries to lift up from the inner end surface of the motor case due to expansion due to temperature changes or vibration of the motor case, the presence of the insulating plate prevents the insulating plate from lifting up and prevents the insulating plate from touching the rotor. Sliding contact can be prevented.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the present invention applied to a cooling fan device, FIG. 1 is a sectional view of a motor case with a stator core attached, FIG. 2 is a perspective view of the cooling fan device, Figure 3 is an enlarged sectional view of the same, Figure 4
The figure is a front view of the stator, and FIG. 5 is an exploded perspective view of the stator, insulating plate, and motor case. FIG. 6 is a sectional view corresponding to FIG. 1 to show the conventional size of the magnetic bridge piece. 7, 7... Salient pole portion, 8... Stator winding, 6...
Stator core, 3... Motor case, 19... Stator winding end, 20... Inner end surface, 18... Insulating plate, 1
1...Magnetic bridging piece.

Claims (1)

[Scope of utility model registration request] A stator core with stator windings wrapped around the salient poles,
This is a small motor that is attached to a motor case and has an insulating plate disposed on the inner end surface of the motor case opposite to the end of the stator winding, and the magnetic bridging piece attached between adjacent salient pole parts is attached to the insulating plate. A small motor characterized by being long so that it is close to the motor.