JP3023518B2 - Electric motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor in which a winding is wound directly on a stator core, the stator core is molded, and a bracket is fixed to the molded stator core.

[0002]

2. Description of the Related Art The applicant has firstly formed a ring-shaped yoke portion on the outer periphery, and provided a plurality of auxiliary poles protruding in the axial direction on the inner peripheral side of the yoke portion; A first winding portion axially protruding from the yoke portion, and an E-shape axially centered on the inner diameter side of the first winding portion. The first winding portion is provided with a first winding, and the first winding portion is adjacent to the pole adjacent to the auxiliary pole beyond the auxiliary pole. An electric motor in which a second winding is applied to a pole to be provided has been proposed.

[0003] With this motor, when the first winding and the second winding are wound around an iron core, the coil end is substantially eliminated. By comparison, the copper dose is reduced by about 30%. Further, this reduces the copper loss, reduces the amount of heat generation, and eliminates the coil end similarly to the motor in which the toroidal winding is applied to the yoke, so that an extremely small induction motor can be formed. In addition, the first and second windings can be wound without dividing the iron core, the magnetic flux density distribution of the air gap between the rotor and the stator approaches a sine curve, the magnetic unevenness is reduced, and the vibration is reduced. A small, quiet and highly efficient induction motor can be obtained, and its manufacture is extremely easy.

[0004]

In the above electric motor,
After winding the first winding and the second winding, the stator core is molded with resin. Then, a bracket is fixed to the molded stator core.

However, conventionally, it is difficult to fix the bracket to the molded stator, and various methods have been proposed. However. In any of the methods, when a metal bracket is fixed to a mold made of resin, the operation steps are complicated, and there is a problem in that other parts are used and the cost is increased.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides an induction motor having the above-mentioned configuration, wherein a motor whose bracket can be easily fixed to a molded stator is used.

[0007]

According to the present invention, there is provided an electric motor in which a stator core is molded, and a bracket is fixed to the molded stator core. It comprises a plurality of auxiliary poles protruding in the axial direction on the inner peripheral side of the iron portion, and a main pole formed between the plurality of auxiliary poles, and the main pole protrudes from the yoke portion in the axial direction. A stator core is constituted by a first winding portion and a tooth portion including three poles protruding toward the axis in an E-shape on the inner diameter side of the first winding portion, and a stator core is formed. A part of the outer peripheral surface other than the inner peripheral surface of the facing stator core, upper and lower surfaces, etc. are pre-molded with a thermoplastic resin to cover the stator core, and are protruded toward the axis in an E-shape. An arc-shaped inner partition wall is integrally provided with the pre-mold on the upper and lower surfaces of the pole base, And a protruding from pawl portions engaged in said partition wall, in which the bracket to the stator core.

[0008]

In the electric motor having the above structure, when the bracket is fixed to the stator core, a claw portion projecting from the bracket is provided on an inner partition wall integrally provided by a pre-mold made of a thermoplastic resin. Is engaged. Thereby, the bracket can be fixed to the stator core.

[0009]

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

FIG. 1 is a plan view of a stator core 10,
FIG. 2 is a perspective view of the stator core 10.

In FIG. 1, a stator core 10 of a motor is shown.
Is formed by laminating a strip-shaped steel plate by a press in a required amount, forming a ring-shaped yoke portion 1 on the outer peripheral side, and on the inner peripheral side of the yoke portion 1 toward the axis 14 of the rotor 12. The six first winding portions 2 that constitute the main pole projecting out are equally arranged.

A tooth portion 3 including three poles 3a, 3b, 3c is formed in an E-shape on the inner diameter side of the first winding portion 2.
The poles 3a, 3b, 3c are formed to have a minimum required width as a magnetic path in order to minimize the volume of the stator core 10. Further, the poles 3a, 3a
Since the teeth 3 composed of b and 3c are formed on the inner diameter side of the first winding 2, six teeth 3 are equally arranged as in the first winding 2. Six auxiliary poles 4 protruding from the yoke part 1 toward the inner diameter side toward the axis 10 are equally disposed between the tooth part 3 and the adjacent tooth part 3 similarly to the tooth part 3. I have.

The inner diameter sides of the poles 3a, 3b, 3c and the auxiliary pole 4 constituting the tooth portion 3 are formed in a series of circular arcs so as to face the outer peripheral surface of the rotor 12 provided adjacently with a small gap therebetween. Is formed. The rotor 12 is supported so as to rotate by a shaft (not shown), and forms a cage rotor 12 in which a secondary conductor is formed on the iron core 10 with an aluminum diecass.

On the outer periphery of the yoke 1, six grooves 8 are provided at equal intervals in the axial direction. The groove 8 is provided on a guide when the core plate constituting the stator core 10 is mounted on the winding machine after pre-molding.

The first winding part 2 is wound with a first winding 6, and is provided with a pole 3 c and a pole 3 a provided via an auxiliary pole 4.
, The second winding 7 is wound. The first winding 6 and the second winding 7 are both wound via both end surfaces of the stator core 10 in the laminating direction, and after winding a required amount, the first winding portion 2 or It is continuously wound around the teeth 3. Then, six first windings 6 and second windings 7 are continuously provided.
Are wound at predetermined positions, the ends of the windings are pulled out and connected to a power source and a capacitor (not shown).

When the first winding 6 and the second winding 7 are wound, an insulating layer is formed in advance on a portion where the windings of the stator core 10 are in contact with each other. Injection molding of a resin called a pre-mold to improve the target strength is performed.

Next, details of the pre-mold of the stator core 10 will be described with reference to FIGS.

The resin used in this pre-mold is a thermoplastic resin, which is liquid at high temperatures and high pressures, so that it can be easily injected into a mold, and the stator core 10 This resin spreads to every corner. When the thermoplastic resin is used, the temperature of the thermoplastic resin decreases from the curing start temperature (about 180 ° C.) to room temperature (about 40 ° C.).

The place where the resin layer 16 is formed by pre-molding the stator core 10 is, as shown in the plan view of the pre-molded stator core 10 in FIG.
0, the upper surface, the lower surface, the groove 8 of the outer peripheral portion of the yoke portion 1, the outer wall of the first winding portion 2, and the outer peripheral portion of the tooth portion 3 including the poles 3a, 3b, 3c are pre-molded to form the resin layer 16. Is done.
As a result, when the stator core 10 is pre-molded with a resin, since the stator core 10 is a thermoplastic resin, the stator core 10 contracts during the period from the curing start temperature to room temperature as described above, and the stator core 10 is tightened. Therefore, the mechanical strength of the stator core 10 is improved by this tightening. A resin layer is not formed on the inner peripheral surface of the tooth portion 3 facing the rotor 12, that is, the inner peripheral surface of the stator core 10 by pre-molding. The thickness of the resin layer 16 by pre-molding is 0.4
mm to 0.7 mm.

The upper surface of the stator core 10 corresponds to the shaft center 1.
Reference numeral 4 denotes a surface on which the bracket 54 of the stator core 10 protrudes, and the lower surface of the stator core 10 denotes a surface on which the shaft center 14 protrudes and is covered by the housing mold of the stator core 10.

The pre-mold has the following features in addition to forming the resin layer by covering the upper surface and the lower surface of the stator core 10 with a resin to improve the mechanical strength.

Reference numeral 50 is an outer partition. This outer partition 5
Numeral 0 is integrally protruded from the upper and lower surfaces of the outer peripheral surface of the yoke portion 1 together with the other resin layer 16 by pre-molding. The outer wall 50 allows the first winding 6
When the second winding 7 is wound around the stator core 10, the winding can be protected without contacting other parts. Further, if the height of the outer partition wall 50 is higher than the coil ends of the first winding 6 and the second winding 7, the stator cores 10 can be stacked, so that the winding operation is facilitated.

Reference numeral 58 denotes a fixing piece for fixing the winding end provided on a part of the outer partition wall 50 (see FIG. 4). The fixing piece 58 protrudes from the upper surface of the outer partition wall 50, and has a concave portion 60 at the center thereof for holding the winding end. If the ends of the windings are fixed to the fixing pieces 58, the end processing of the stator windings can be mechanized. That is, when a winding is placed on the stator core 10,
If the winding is left as it is, the winding may be loosened. However, if the end of the winding is fixed to the fixing piece 58, the winding will not be loosened.

In the fixing piece 58 of this embodiment, the winding end is fixed by providing a concave portion 60 as shown in FIG. 4, but instead of this, the winding end is sandwiched by the outer partition wall 50. Alternatively, a structure may be used in which a concave portion is provided directly, or two fixed pieces are protruded at shifted positions, and the winding ends are sandwiched between the shifted positions.

Reference numeral 66 denotes an inner partition wall 66 protruding from the lower surface of the stator core 10. The inner partition walls 66 are six arc-shaped partition walls protruding along the lower surface of the base of the tooth portion 3 composed of the E-shaped poles 3a, 3b, 3c. The role of this intermediate partition 66 is to make the first winding 6 and the second winding 7
With the inner partition 66.
There is no contact between the first winding 6 and the second winding 7. In particular, since the inner partition wall 66 is formed in an arc shape, even if the inner partition wall 66 is protruded from the lower surface of the stator core 10, its strength is sufficient and the first winding 6 falls down to the inner peripheral side. To prevent

Reference numeral 52 denotes a middle partition wall on the upper surface of the stator core 10. The inner partition 66 is a pole 3 formed in an E-shape.
This is a partition wall of the arc-shaped first winding 6 and second winding 7 provided along the upper surface of the base of the tooth portion 3 composed of a, 3b, and 3c. The inner partition wall 52 is protruded higher than the inner partition wall 66, and when the electric motor is assembled, the upper end reaches the bracket 54. The bracket 54 is fixed to the stator core 10 by making a claw 56 projecting from the outer peripheral portion of the bracket 54 made of a steel plate bite into the inner partition wall 52. In this case, since the pre-mold made of a thermoplastic resin is softer than the resin of the housing mold that covers the entire electric motor, the claw portion 56 of the bracket 54 can be easily cut into the pre-mold. That is, when the claw portion 56 of the bracket 54 is to be digged in, only the upper end portion of the inner partition wall 52 is heated by ultrasonic waves or the like to be soft, and the claw portion 56 is attached while the inner partition wall 52 is soft.

Reference numeral 68 denotes a main pole inner partition wall protruding from the ends of the poles 3a, 3b, 3c in an arc shape. The main pole inner partition wall 68 is for preventing the second winding 7 from falling to the inner peripheral side. Further, as shown in the drawing, since the second winding 7 is formed in a sloping shape, the second winding 7 is settled in a predetermined position.

Reference numeral 70 denotes an auxiliary pole inner partition provided at the tip of the auxiliary pole 4. This auxiliary pole inner partition wall 70 is also for preventing the second winding 7 from falling to the inner peripheral side. The inner wall 70 for the auxiliary pole is also formed so as to become more sloping toward the inner side, and the second winding 7 is formed so as to fit in a predetermined position.

Reference numeral 72 denotes a bushing integrally formed by pre-molding (see FIGS. 9 and 10).
The bushing 72 includes a bushing body 74 protruding from the outer periphery of the yoke 1 and a lid 76 rotatably provided on the body 74. Then, at the base of the main body 74,
An insertion portion 78 for inserting the ends of the first winding 6 and the second winding 7 is provided. When assembling the bushing 72, after soldering the ends of the first winding 6 and the second winding 7 and the tip of the lead wire 80 of the lead bump, the soldered portion 82 is inserted into the insertion portion 78. Insert and cover the lid 76 (see FIG. 10).

As a result, it is not necessary to attach only the bushing from the outside as in the related art, so that the assembling process can be simplified and the cost can be reduced. In the case where the bushing is integrally formed, the cost can be further reduced and the working efficiency can be improved by forming the relay holding portion and the connection insulating portion as an integrally formed product.

When the stator core 10 having the above-described configuration is pre-molded, the mechanical strength of the stator core 10 is improved by performing the pre-molding, and further, the first winding 6 and the second winding 7 are formed. Can be insulated.

[0032]

As described above, according to the motor of the present invention,
The bracket can be easily fixed to the stator core by engaging the claw protruding from the bracket with the inner partition wall provided integrally by pre-molding.

Therefore, the working efficiency in the manufacturing process of the electric motor can be increased, and the cost is reduced because no other parts are used.

[Brief description of the drawings]

FIG. 1 is a plan view of a stator core.

FIG. 2 is a perspective view of a stator core.

FIG. 3 is a plan view of a stator core in a pre-molded state.

FIG. 4 is a partially enlarged perspective view of a stator core in a pre-molded state.

FIG. 5 is a sectional view taken along line BB in FIG . 3;

FIG. 6 is a sectional view taken along line AA in FIG . 3;

FIG. 7 is a semi-longitudinal sectional view of the electric motor.

FIG. 8 is an enlarged cross-sectional view of a state in which a claw portion of a bracket has digged into a middle partition.

FIG. 9 is an enlarged perspective view of a bushing.

FIG. 10 is an enlarged sectional view of a bushing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Yoke part 2 ... 1st winding part 3 ... Tooth part 3a, 3b, 3c ... Pole 4 ... Complementary pole 5 ... Rotor 12 6 ... 1st winding 7 ... 2nd Winding 10 Stator core 12 Rotor 16 Resin layer 50 Outer partition 52 Middle partition 54 Bracket 56 Claw 58 Fixing piece 60 Middle recess 66 Middle Partition wall 68: Main partition inner partition wall 70: Complementary electrode inner partition wall 72: Bushing 74: Bushing body 76: Lid 78: Insertion section 80: Lead wire

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02K 5/04-5/08 H02K 5/15

Claims (1)

(57) [Claims] 1. An electric motor in which a stator core is molded and a bracket is fixed to the molded stator core, wherein a ring-shaped yoke portion is formed on an outer periphery, and an axial yoke is formed on an inner peripheral side of the yoke portion. A first winding portion comprising a plurality of protruding auxiliary poles, and a main pole formed between the plurality of auxiliary poles, the first winding portion projecting the main pole from the yoke portion in the axial direction; The stator core is composed of three poles protruding toward the axis in an E-shape on the inner diameter side of the winding part, and the stator core is formed except for the inner peripheral surface of the stator core facing the rotor. Part of the outer peripheral surface, upper and lower surfaces, etc. are pre-molded with a thermoplastic resin to cover the stator core, and the upper and lower surfaces of the bases of the three poles protruding toward the axis in an E shape are arc-shaped. The inner bulkhead is integrally protruded with the pre-mold, and the claw protruding from the bracket is And engaged, the motor being characterized in that the bracket to the stator core.