JP2008005617A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor capable of attaining cost reduction by reducing the weight of a rotor because of no frame as a structure. <P>SOLUTION: This motor having a structure made of resin without using a frame 107, includes a plurality of air holes 20 for penetrating the resin portion 19 of the rotor 12 in the axial direction, and with extended projections 21 made of resin on the inner circumferential side. The motor includes through-holes 22 in the axial direction on the outer-periphery surface of the inner side rotor 14 and on the inner-periphery surface of an outer rotor 15 of the rotor and radial resin ribs 24 on step-off portions 23 of the rotor 12 in the axial direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an electric motor used in a washing machine or the like.

  Conventionally, in this type of electric motor, the stator 101 and the rotor 102 are separated, and for example, there is one shown in FIG. FIG. 5 shows a perspective view of the electric motor, FIG. 6 shows a state where the stator 101 and the rotor 102 of the electric motor are separated, and FIG. 7 shows a cross section of the stator 101 and the rotor 102 of the electric motor.

  The stator core 103 and the like are attached to an actual machine such as a washing machine by using holes provided in the mounting legs 104 extending in the radial direction of the stator 101 whose exterior is covered with resin or the like. A rotor 102 is rotatably held on a shaft of the actual machine via a boss 105 inside a stator 101 attached to the actual machine. At this time, the rotor 102 generally has a magnet.

  Here, the rotor 102 has a frame 107 as a structure. Furthermore, there is an air hole 106 in the axial direction, and the heat trapped inside the rotor 102 is naturally released from the air hole 106. Since such prior art is not related to the literature known invention, there is no prior art document information to be described.

  However, since the conventional configuration includes the frame 7 as a structure, the weight of the rotor 2 increases and the cost also increases. Moreover, although the heat accumulated inside the rotor 2 is released from the air holes 6, only the heat inside the rotor 2 is released, and the heat is spontaneously released, resulting in poor heat dissipation efficiency. In addition, a magnet is embedded in the vicinity of the rotor core 8, and when the electric motor is assembled to the washing machine, there is a problem that it is difficult to assemble the magnet due to the attractive force of the magnet.

In order to solve the above-mentioned problem, the present invention forms a structure with resin without using the frame 107, and provides a plurality of air holes 20 penetrating in the axial direction in the resin portion 19 of the rotor 12, Protrusions 21 extending from the resin are provided on the inner peripheral side, and axial through holes 22 are provided on the outer peripheral surface of the inner rotor 14 of the rotor and the inner peripheral surface of the outer rotor 15. Radial resin ribs 24 are provided at the step portions 23 in the direction.

  As described above, according to the electric motor of the present invention, since there is no frame as a structure, the weight of the rotor can be reduced and the cost can be reduced.

  Further, the heat generated from the stator is agitated by the rotation of the convex portion extended from the resin on the inner peripheral side of the air hole together with the rotor, and heat is radiated in the rotational tangential direction of the tip of the convex portion. Heat is released from the air holes provided in the. Therefore, heat accumulated in the rotor and the stator can be forcibly released from the air holes, and the heat dissipation efficiency can be increased.

  In addition, by inserting a jig through an axial through hole provided on the outer peripheral surface of the inner rotor of the rotor or the inner peripheral surface of the outer rotor, the magnets embedded in the vicinity of the rotor core are attracted when the electric motor is assembled to the washing machine. The problem that it is difficult to assemble by force disappears.

The structure is formed of resin without using a frame, and a plurality of air holes penetrating in the axial direction are provided in the resin portion of the rotor, and a convex portion extended by the resin is provided on the inner peripheral side thereof. Provided. Further, axial through holes were provided in the outer peripheral surface of the inner rotor of the rotor and the inner peripheral surface of the outer rotor. Further, radial resin ribs were provided at the step portions in the axial direction of the rotor.

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1)
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1, 2, 3, and 4.

The motor shown in FIG. 1 represents a toroidal winding brushless motor, and includes a stator 11 and a rotor 12. The stator 11 has a stator core 13 and a plurality of coils that are connected in a three-phase star or delta shape and are provided with toroidal windings on the stator core 13. The rotor 12 is rotatably held with respect to the stator 11, and includes an inner rotor 14 that faces the inner diameter side of the stator 11 and an outer rotor 15 that faces the outer diameter side, and the inner rotor 14 and the outer rotor 15. The permanent magnet 16 is disposed at a position facing the stator teeth.
It is attached to an actual machine such as a washing machine by using holes provided in the mounting legs 17 extending in the radial direction of the stator 11. The process is the same as in the background art until the rotor 12 is rotatably held on the shaft of the actual machine through the boss 18 inside the stator 11 attached to the actual machine.

  The electric motor of the present invention has a structure in which the inner rotor 14, the outer rotor 15, and the boss 18 are inserted into a resin molding die without using a frame in the rotor structure, and almost all of these parts are externally covered with the resin portion 19. It is.

  Therefore, since there is no frame as a structure, the weight of the rotor is reduced and the cost is reduced.

(Example 2)
A plurality of air holes 20 penetrating in the axial direction are provided in the resin portion 19 of the rotor 12, and a convex portion 21 extending from the resin is provided on the inner peripheral side thereof. When the rotor 12 rotates around the axis of the actual machine, the heat generated from the stator 11 is agitated by the rotation of the convex portion 21 extending from the resin on the inner peripheral side of the air hole 20 together with the rotor 12. Heat is radiated in the direction of the rotational tangent of the outer peripheral tip portion, and heat is released from the air hole 20 provided at the radiation destination.

  Therefore, the heat dissipation efficiency is increased.

(Example 3)
On the outer peripheral surface of the inner rotor 14 of the rotor 12 and the inner peripheral surface of the outer rotor 15, there are axial through holes 22. The through hole 22 is located in the axial direction of the gap portion between the inner rotor 14 and the inner peripheral side of the stator core 13 of the stator 11. When attaching the rotor 12 to the stator 11 previously attached to the actual machine, a jig capable of passing the gap portion between the inner rotor 14 and the inner peripheral side of the stator core 13 of the stator 11 is inserted into the through hole 22, The rotor 12 is attached to the actual machine. After the attachment of the rotor 12 to the actual machine is completed, the attachment of the rotor 12 to the actual machine is completed by removing the jig. Here, the through hole 22 may be provided on the inner peripheral surface of the outer rotor 15. In that case, the through hole 22 is located in the axial direction of the gap portion between the outer rotor 15 and the outer peripheral side of the stator core 13 of the stator 11.

  Therefore, the problem that it is difficult to assemble due to the attractive force of the magnet embedded in the vicinity of the rotor core when the electric motor is assembled to the washing machine is eliminated.

Example 4
The rotor 12 has radial resin ribs 24 in the stepped portion 23 in the axial direction. The rib 24 can compensate for the decrease in strength due to the abolition of the frame without increasing the amount of resin, and can further suppress the amplitude of the vibration mode of the rotor 12 to reduce vibration noise during operation of the motor. To do.

  According to the electric motor of the present invention, the weight of the rotor is reduced, the cost is reduced, and the heat dissipation efficiency is increased. Further, when the electric motor is assembled to the washing machine, the assembling becomes easy, which is useful for applications such as an electric motor used for the washing machine.

Assembly drawing of electric motor in one embodiment of the present invention Exploded view seen from the front Exploded view from the back Cross section Assembly drawing of a motor showing a conventional example Exploded view seen from the front Cross section

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Stator 12 Rotor 13 Stator core 14 Inner rotor 15 Outer rotor 16 Permanent magnet 17 Mounting foot 18 Boss 19 Resin part 20 Air hole 21 Convex part 22 Through hole 23 Step part 24 Rib 101 Stator 102 Rotor 103 Stator core 104 Attachment leg 105 Boss 106 Air hole 107 Frame 108 Rotor core

Claims (4)

A stator having a plurality of coils connected to each other in a three-phase star or delta shape and provided with a toroidal winding on the yoke of a stator core formed of a substantially annular yoke and a plurality of teeth provided on the yoke; And the rotor is configured by an inner rotor that faces the inner diameter side of the stator and an outer rotor that faces the outer diameter side, and the teeth extend from the yoke in the outer circumferential direction. The outer teeth that protrude and inner teeth that protrude in the inner circumferential direction from the yoke in the same number as the outer teeth, and the inner rotor and the outer rotor are provided with holes for permanent magnet insertion, In a rotor of a motor having a plurality of inner rotor permanent magnets and outer rotor permanent magnets stored and held in a frame, a frame is formed on the rotor structure. Without using the electric motor, characterized in that to form the structure of a resin An electric motor comprising a plurality of air holes penetrating in an axial direction in a resin portion of the rotor, and a convex portion extending from the resin on an inner peripheral side thereof An electric motor having an axial through hole on an outer peripheral surface of an inner rotor of the rotor or an inner peripheral surface of an outer rotor. An electric motor having radial resin ribs in the axial step portion of the rotor