JPH0564537B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a small electric motor, and particularly relates to insulation of a stator core.

(b) Prior art In general, the insulation between the iron core, stator windings, crossover wires, and wiring of an electric motor consists of inserting sheets of insulating paper into the slots of the iron core one by one, so assembly is not done by hand. It was time consuming. Furthermore, since this insulating paper is simply inserted, there are cases where the insulating paper falls out from the slot.

Furthermore, as mentioned above, instead of using insulating paper, a synthetic resin with good insulation and heat resistance and low moisture absorption is used to create insulation between the slots of the core, the yoke, etc., and the stator windings and crossover wires. Some of them were molded in such a way that they were interposed to maintain the necessary insulation distance. Although such insulation means ensure insulation between the iron core and the stator windings, they cannot sufficiently insulate and protect the crossover wires connecting the stator windings.

In addition, in the design of smaller electric motors in recent years,
Sufficient insulation and protection of crossover wires could not be achieved without extensive use of protective tubes.

Therefore, if the crossover wire is long and there are many connecting wires,
The process of drawing out and connecting crossover wires becomes complicated,
At the same time, protecting the crossover wires has been an obstacle to making the electric motor more compact.

(c) Purpose of the Invention The present invention, which was created in view of the above problems, does not require any special means such as a protective tube as a protection means for crossover wires or wiring, and furthermore, allows for easy pulling out of crossover wires. The present invention provides a compact electric motor that can be made smaller than before.

(d) Structure of the Invention The small electric motor of the present invention is composed of a plurality of teeth arranged on a concentric circle around a hole that accommodates a rotor, and a circular yoke that connects the outer periphery of these teeth. In a small electric motor having a stator core, the stator core has an insulating part for insulating between the stator core and the stator windings, and an insulating part is provided continuously along the concentric circle on the end face of the yoke. The two rows of protective walls that are placed in the inner protective wall and the guide rod that is higher than the protective wall and are installed in the cutout position of the inner protective wall are integrally molded from synthetic resin, and the guide rod is made of synthetic resin to guide the ends of the stator windings wound around the teeth. It is configured so that it is led into two rows of protective walls after being hooked to a rod, insulating and protecting the stator windings and the iron core, and the crossover wires and wiring from the core and brackets. This makes it easy to draw out the wiring.

In addition, the guide rod is integrally made of synthetic resin with a rib-shaped protrusion extending along the inner wall of the slot, and this protrusion is used as a path for the synthetic resin to prevent molding defects in the synthetic resin. It is intended to do so.

(E) Embodiment Below, embodiments of the present invention will be explained based on FIGS. 1 to 7. First, in FIG.
is formed by drawing with a mold, and in particular, a through hole 4 is machined in the bracket 2, through which the rotating shaft 3 passes. 5
is a rotor, which includes the rotating shaft 3, a rotor core 6 made of laminated iron plates made of silicon steel plates or electric iron plates,
It consists of a rotor core 6 and permanent magnets 7 made of ferrite glued around it. Reference numeral 8 is a metal bearing of the rotating shaft 3, which is supported in a self-aligning structure. Reference numeral 9 denotes a stator consisting of an iron core 10, a synthetic resin material 11, a stator winding 12, etc., and the structure before winding the stator winding 12 as shown in FIGS. 2 to 5 and the structure shown in FIGS. As can be seen from the structure in which the stator winding 12 is wound as shown in FIG. Crossing line 14 connecting between
Protective walls 15 and 16 that guide the
A guide rod 17 pulled out from 5 and 16 is made of synthetic resin injection molding. The guide rod 17 is higher than the protective walls 15 and 16 and has a semi-cylindrical shape, and in particular, the guide rod 17' provided in contact with the slot has a rib-shaped protrusion 18 extending from the inner wall of the slot. This convex portion 18 is surrounded by the bottom surface of the stator 9 as shown in FIG. As a result, even when the synthetic resin is injected only from the top surface of the stator 9, the synthetic resin flows well and the synthetic resin is sufficiently distributed to the bottom surface of the stator 9. Note that 19 is the mark of a gas vent hole provided in the mold.

By configuring as above, the iron core 10
A sufficient insulation distance is secured between the stator winding 12 and the stator winding 12 by injection molding of synthetic resin. Further, since the connecting wire 14 passes between the protective walls 15 and 16, the connecting wire 14 and the iron core 10 can be insulated and the connecting wire 14 can be sufficiently protected without providing any protective means such as a protective tube.

That is, the crossover wire between the stator windings can be housed within the protective wall, and the insulation and protection between the crossover wire and the stator winding and between the crossover wire and the bracket can be easily protected. Therefore, insulation and protection of the crossover wire can be maintained even if the distance between the crossover wire and the bracket (the width of the yoke part) is shortened, so the insulation distance can be secured by extending the coil end of the stator winding in the axial direction. There's no need to. Therefore, the diameter of the motor can be easily reduced without increasing the axial length of the motor.

Furthermore, the guide rod 17 is higher than the protective walls 15 and 16.
By using the guide rods 17 and 17', the step of pulling out or inserting the connecting wire 14 from between the protective walls 15 and 16 can be easily carried out by hooking the connecting wire 14 to the guide rods 17 and 17'. In other words, the crossover wire 14
can be easily introduced into the protective wall.

Furthermore, by hooking the crossover wire 14 to the guide rods 17, 17', it is possible to prevent the crossover wire 14 from coming off the protective wall, and also to position the crossover wire 14, thereby preventing variations in the crossover wire 14. It is something that can be done.

Incidentally, the above-mentioned crossover wire 14 is connected to an external lead wire via a connector 19.

(F) Effects of the Invention The small electric motor of the present invention is composed of a plurality of teeth arranged on a concentric circle around a hole that accommodates a rotor, and a circular yoke that connects the outer periphery of these teeth. In a small electric motor having a stator core, the stator core includes an insulating part that provides insulation between the stator core and the stator windings, and an insulating part that is continuously provided on the end face of the yoke along the concentric circle. Two rows of protective walls and a guide rod installed in a notch in the inner protective wall and higher than the protective wall are integrally molded with synthetic resin, and the ends of the stator windings wound around the teeth are connected to the guide rod. Since the wires are hooked onto the wire and then guided into two rows of protective walls, insulation and protection between the crossover wire and the stator winding, as well as between the crossover wire and the bracket, can be easily ensured even if the width of the yoke portion is narrowed. The diameter of this electric motor can be easily reduced without increasing the axial length of the motor.

Furthermore, the guide rod facilitates the introduction of the crossover wire into the protective wall, thereby simplifying the assembly process of the electric motor. In addition, if the guide rod is extended along the inner wall of the slot with a rib-shaped convex part and can be integrally molded with synthetic resin, when the synthetic resin is injected from one side of the stator, the synthetic resin will pass through this convex part. The hot water flow is good, the synthetic resin can be molded uniformly, and molding defects of the stator can be prevented.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a small electric motor showing an embodiment of the present invention, Fig. 2 is a top view of the stator shown in Fig. 1, and Fig. 3 is a -' sectional view of the stator shown in Fig. 2; Figure 4 is a bottom view of the stator shown in Figure 1, Figure 5 is a perspective view of the stator shown in Figures 2 to 4, and Figure 6 shows the stator windings on the stator shown in Figure 5. FIG. 7 is a side view of the stator and stator winding shown in FIG. 6. 10... Iron core, 12... Stator winding, 13...
Insulating section, 14... Crossing wire, 15, 16... Protective wall, 17, 17'... Guide rod, 18... Convex portion.

Claims (1)

[Scope of Claims] 1. A stator core comprising a plurality of teeth arranged concentrically around a hole that accommodates a rotor and a circular yoke that connects the outer periphery of these teeth. In a small electric motor, a stator core includes an insulating section that provides insulation between the stator core and the stator windings, and two rows of protective walls that are continuously provided on the end face of the yoke along the concentric circles. and a guide rod installed in a notch in the inner protective wall and higher than the protective wall are integrally molded with synthetic resin, and the ends of the stator windings wound around the teeth are hooked onto the guide rod. A small electric motor characterized by being guided within two rows of protective walls. 2. The small electric motor according to claim 1, wherein the guide rod extends along the inner wall of the slot with a rib-like convex portion and is integrally formed of synthetic resin.