KR100447185B1 - Rotor assembly of outer rotor type induction motor - Google Patents

Abstract

The present invention is to improve the rotor of the outer rotor type induction motor, to facilitate assembly and to improve mass production, and to reduce the manufacturing cost and product cost.

To this end, the present invention, in the outer rotor type induction motor including a rotor having a laminated iron core and a stator wound around the coil, the laminated iron core is provided, the boss on the bottom A cylindrical rotor core to be formed, a screw fastening portion corresponding to a boss formed on a bottom surface of the rotor core, a housing screwed to the rotor core, and a central portion of the housing and coupled to an external shaft. Provided is a rotor assembly of an outer rotor type induction motor, characterized in that it comprises a bushing rotor.

Description

Rotor assembly of outer rotor type induction motor

The present invention relates to an induction motor, and more particularly to a rotor assembly of an outer rotor type induction motor.

In general, an induction motor is a device that rotates a shaft directly connected to a shaft requiring driving without a separate power transmission means (especially a belt), and is widely used in a drum washing machine, a pulsator washing machine, etc., in which a washing tank is rotated.

Among them, the outer rotor type induction motor is, as is well known, a rotor, which is a rotor having a circumferential portion in which a plurality of ring-shaped thin plates are stacked, and a bottom portion engaged with an outer shaft, and a predetermined inner circumferential surface of the rotor. It consists of a stator, which is a fixed body that is provided at intervals, and a coil is wound along a circumference, and the rotational force generated by the interaction between the rotating magnetic field generated by the alternating current flowing through the coil of the stator and the induced current generated in the rotor. Will work

Hereinafter, the rotor of the outer rotor type induction motor according to the prior art will be described in detail with reference to FIGS. 1 and 2.

Conventional rotors include a housing (1) made of steel and a rotor core (2) forcibly pressed into an inner circumferential surface of the housing, and a bottom surface of the housing. It consists of a bushing rotor (3, bushing rotor) of steel material which is screwed on and coupled to an external shaft (not shown).

In addition, the rotor core will be described in more detail. The rotor core includes a laminated iron core in which a plurality of ring-shaped thin steel plates having a plurality of through holes (not shown) formed along a circumference thereof are laminated in multiple layers to correspond to the through holes ( 2a), a vertical core (not shown) provided in the through hole to fix the iron plates and exposed to the upper and lower portions of the laminated iron core 2a, and fixing the upper and lower ends of the vertical core, It consists of a ring-shaped ending member 2b provided on the upper and lower surfaces of the laminated iron core 2a, respectively. At this time, the vertical core and the end member 2b are formed together on the laminated iron core 2a by die casting casting.

However, the rotor of the outer rotor type induction motor according to the prior art made as described above had the following problems.

First, when the rotor core 2 is press-fitted into the housing 1, the rotor core must be press-fitted while maintaining the center of the housing 1 and the center of the rotor core 2 accurately. There was a problem with time delay.

Second, when using a separate indentation jig (not shown) that maintains the center correctly, there is a problem that the production cost is increased, and a separate process for using it has a problem that the productivity is lowered.

Third, a press die (not shown) is used to make the shape of the housing 1, which is a cutting die for cutting into a unit member, an upper mold for making the upper shape of the housing, and a lower shape for making the shape of the housing 1. The lower mold, and a number of other molds for making heat dissipation holes on the exterior or the bottom surface are required, resulting in a large mold cost burden, and these molds increase the number of processes for press working, resulting in a decrease in mass productivity. there was.

Fourth, the housing 1 is made of a steel material, there was a problem that the vibration or noise generated when the rotor is rotated directly to the other member (outer tub in the case of a washing machine).

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a rotor assembly of an outer rotor type induction motor, which facilitates assembly, improves mass production, and reduces manufacturing cost and product cost.

1 is a perspective view showing a rotor of an outer rotor type induction motor according to the prior art.

Figure 2 is in accordance with the prior art, an exploded perspective view showing the assembly process of the rotor.

Figure 3 is a perspective view of the rotor of the outer rotor type induction motor according to the present invention.

Figure 4 is in accordance with the present invention, an exploded perspective view showing the assembly process of the rotor.

Explanation of symbols for main parts of the drawings

10: rotor core 11: laminated core

13: boss 20: housing

21: fastening portion 21a: guide groove

22: seating portion 23: heat sink

24: rib 30: bushing rotor

In order to achieve the above object, the present invention, in the outer rotor type induction motor including a rotor having a laminated iron core and a stator wound around the coil, the laminated iron core is provided, the boss on the bottom Cylindrical rotor core (boss) is formed, a screw fastening portion corresponding to the boss formed on the bottom surface of the rotor core is formed to be screwed with the rotor core, the central portion of the housing is provided outside Provided is a rotor assembly of an outer rotor type induction motor, characterized in that it comprises a bushing rotor coupled with the shaft.

At this time, it is preferable that a coupling part having a boss or a coupling groove for screwing the housing is selectively formed on the bottom of the rotor core, and screwing the rotor core on the inner bottom of the housing. It is preferable that the fastening part is further formed.

In addition, the rotor core is correctly seated at the center point of the housing, and the boss of the rotor core is positioned at the fastening portion of the housing so that the fastening portion is further formed with a guide groove for guiding the boss. More preferred.

In addition, the housing is preferably made of a resin (resin) material to be injection molded at a time.

Therefore, by providing a rotor assembly of the outer rotor type induction motor according to the present invention, the assembly is easy to improve the mass production, and the manufacturing cost and the product cost can be reduced.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Figure 3 is a perspective view showing a rotor of the outer rotor type induction motor according to the present invention, Figure 4 is an exploded perspective view showing the assembly process of the rotor, according to the present invention.

Prior to the drawing description, since the outer rotor type induction motor has been mentioned in the prior art, the description thereof is omitted.

As shown in FIGS. 3 and 4, the rotor assembly of the outer rotor type induction motor according to the present invention is provided with a laminated iron core 11 in which a plurality of ring-shaped iron plates are stacked, and an upper and lower end members, respectively. Cylindrical rotor core 10 provided with 12, a housing 20 screwed to the bottom surface of the rotor core, and a bushing rotor 30 is provided in the central portion of the housing and coupled to an external shaft (not shown) ) Is included.

In addition, a coupling portion for screwing the housing 20 and the lower surface of the rotor core 10 may be further formed.

In this case, as shown in the drawing, it is preferable that the boss 13 protrudes from the bottom surface of the rotor core 10, and more specifically, the boss 13 of the rotor core 10 is formed. It is preferable to be formed on the bottom of the lower end member 12, and, if the end member 12 is formed by die casting casting method, it is more preferable that the boss 13 is also formed together with this.

In addition, although not shown in the coupling portion, in another embodiment, only the coupling groove may be formed on the bottom surface of the rotor core 10. Specifically, it is more preferable that the coupling groove is formed on the bottom surface of the lower ending member 12 of the rotor core 10.

On the other hand, it is preferable that a fastening portion 21 for screwing with the boss 13 of the rotor core is further formed on the inner bottom surface of the housing 20.

Of course, although not shown, only the boss 13 may be formed to be screwed to the housing 20, or only the fastening portion 21 may be formed to be screwed to the rotor core 10.

In addition, the rotor core 10 is accurately seated at the center point of the housing 20, and the boss 13 of the rotor core is accurately positioned at the fastening portion 21 of the housing, thereby producing workability and mass production. In order to improve the performance, the fastening portion 21 is more preferably formed with a guide groove (21a) for guiding the boss (13).

On the other hand, the housing 20 is preferably made of a resin material to be injection molded at a time, it is possible to improve the mass productivity as it is injection molded at a time.

In addition, the resin material has the advantages of lower cost than the steel material used in the prior art, thereby reducing the cost of the product, the advantage of reducing the inertia due to the low weight, and the low rigidity to reduce vibration and noise. It has an advantage to make.

In addition, the inner peripheral surface of the housing 20, it is preferable that the stepped mounting portion 22 is further formed so that the bottom surface of the rotor core 10 is smoothly seated, this also workability and mass productivity It is one of the components that can be improved.

In addition, the heat dissipation hole 23 for dissipating heat may be further formed in the circumference and the bottom of the housing 20, and in addition, the inner bottom surface of the housing 20 may provide the heat when the housing is rotated. More preferably, the rib 24 serving as a blade for cooling or applying air to smoothly discharge the heat to the heat dissipation hole 23 is formed. In addition, the rib 24 also serves to reinforce the strength of the housing 20.

Here, the heat dissipation hole 23 and the rib 24, unlike the prior art that requires a separate molding process for punching or sectioning, will be injection molded at the same time when the housing 20 is injected.

On the other hand, the bushing rotor 30 is preferably screwed and fixed to the inner bottom surface center portion of the housing 20.

The bushing rotor 30 is more preferably made of a resin material. Because, as described above, the resin material has the advantages of lower cost than the steel material used in the prior art to reduce the unit cost, the advantage of reducing the inertia due to the low weight, the advantage of reducing the vibration and noise due to the small rigidity, etc. It is because it has, and when used with the housing 20 made of a resin material it can double the advantages.

In addition, although not shown, the bushing rotor 30 may be injection molded integrally with the housing 20 in another embodiment. In another embodiment, the bushing rotor 30 is coupled to an outer shaft for strength reinforcement. The serration part 31 of 20 may be pre-machined from a metal material, and then integrally molded together with the housing 20 by an insert injection method.

Herein, the insert injection method will be described in detail, and the serration part 31 is inserted into a mold for insert injection (not shown) having a bushing rotor 30 (a part without the serration part) and a shape having a shape of the housing 20. When the pressure is applied to the resin, the resin adheres to the serration part together with the shape of the housing and the bushing rotor (the part without the serration part), so that the serration and the housing are integrally formed.

Hereinafter, with reference to Figure 4, the assembly process of the rotor assembly of the outer rotor type induction motor according to the present invention made as described above will be described with reference to the most preferred embodiment.

First, a boss 13 is formed on the bottom surface of the rotor core 10, and the housing includes the fastening part 21, the guide 21 a, the seating part 22, the heat dissipation hole 23, and the rib 24. 20 and the bushing rotor 30 are injection molded.

Thereafter, the boss 13 is introduced into the guide groove 21a so that the boss 13 of the rotor core 10 is guided along the guide groove 21a of the housing 20, and the boss 13 To face the fastening part 21, and then screw the fastening part 21 and the boss 13 sequentially to couple the rotor core 10 to the housing 20. Then, the bushing rotor 30 is screwed to the center of the bottom surface of the housing 20.

Therefore, by providing a rotor assembly of the outer rotor type induction motor according to the present invention, the assembly is easy to improve the mass production, and the manufacturing cost and the product cost can be reduced.

As described above, the present invention has been described by limiting the screw fastening method in order to easily assemble the housing 20 and the rotor core 10, in addition to this method it will be easy to be assembled in a number of different ways.

For example, although not shown, in another embodiment of the present invention, the rotor core 10 and the housing 20 may be integrally formed by an insert injection method.

That is, when the rotor core 10 is placed in an insert injection mold (not shown) in which a bone having a shape of the housing 20 is formed and pressure is applied to the resin, the resin adheres to the rotor core together with the housing shape. The rotor core and the housing are made integral.

So far, the present invention has been described with reference to the preferred embodiments, and those skilled in the art to which the present invention pertains to the detailed description of the present invention and other forms of embodiments within the essential technical scope of the present invention. Could be implemented. Here, the essential technical scope of the present invention is shown in the claims, and all differences within the equivalent range will be construed as being included in the present invention.

As described above, the present invention provides the rotor assembly of the outer rotor type induction motor, has the following advantages.

First, according to the present invention, the parts such as the housing are made by injection molding which can be molded at one time, and the housing and the rotor core can be easily assembled, thereby improving mass productivity.

Second, according to the present invention, as the assembly process is simple and easy, the manufacturing cost is reduced, and as a result, the product cost is lowered. In particular, there is an advantage that the manufacturing cost is reduced by about 10% compared to the conventional.

Third, according to the present invention, the rigidity of the components can be reduced by using the resin material, which can reduce vibration and noise.

Fourth, according to the present invention, the weight of the parts can be reduced by using the resin material, there is an advantage that can reduce the influence of inertia during rotation stop. In particular, the weight can be reduced by about 40.7% compared to the conventional, the effect of inertia has an advantage that can be reduced by about 52% compared to the conventional.

It also encompasses all the effects mentioned in the detailed description of the invention.

Claims (11)

In an outer rotor type induction motor including a rotor having a laminated iron core and a stator wound with a coil, A cylindrical rotor core having the laminated iron core and having a boss formed on a bottom thereof; A housing in which a screw fastening portion corresponding to a boss formed on a bottom surface of the rotor core is formed and screwed with the rotor core; The rotor assembly of the outer rotor type induction motor, characterized in that comprises a bushing rotor provided in the central portion of the housing and coupled to the outer shaft. delete delete The method of claim 1, A guide groove for guiding the boss is further formed at the screwing portion of the housing so that the rotor core is correctly seated at the center point of the housing and the boss of the rotor core is exactly positioned at the screwing portion of the housing. Rotor assembly of the outer rotor type induction motor, characterized in that. The method of claim 1, The rotor assembly of the outer rotor type induction motor, characterized in that the inner circumferential surface of the housing is further formed with a step-shaped mounting portion is seated on the bottom surface of the rotor core. The method according to claim 1 or 5, The rotor assembly of the outer rotor type induction motor, characterized in that the heat dissipation hole for dissipating heat is further formed in the peripheral portion and the bottom portion of the housing. The method according to claim 1 or 5, The inner bottom surface of the housing, the rotor assembly of the outer rotor type induction motor, characterized in that it further provided with a rib to cool the heat when the housing rotates or the air is smoothly discharged to the outside. The method of claim 1 The housing, the rotor assembly of the outer rotor type induction motor, characterized in that made of a resin (resin) material. The method of claim 8, The rotor assembly of an outer rotor type induction motor, wherein the bushing rotor is integrated with the housing, and the serration part directly coupled to the outer shaft of the bushing rotor is inserted. In an outer rotor type induction motor including a rotor having a laminated iron core and a stator wound with a coil, A cylindrical rotor core provided with the laminated iron core, A housing which is inserted into the insert with the rotor core, The rotor assembly of the outer rotor type induction motor, characterized in that comprises a bushing rotor provided in the central portion of the housing and coupled to the outer shaft. The method of claim 10, Heat dissipation holes for dissipating heat are further formed in the circumference and the bottom of the housing, The inner assembly of the outer rotor, rotor assembly of the outer rotor type induction motor, characterized in that the cooling of the heat during the rotation of the housing or the air is applied to the air to smoothly discharge to the heat dissipation hole is formed.