JPH11128588A - Motor for washing machine - Google Patents

Abstract

(57) [Problem] To provide a high efficiency, low cost, low noise motor for a washing machine. SOLUTION: A washing / dewatering tub 2, a stirring blade 3, and a motor 5 are provided.
Are arranged coaxially, the rotating shaft 8 of the rotor 7 is connected via the clutch / deceleration mechanism 4, the rotor 7 is arranged on the outer peripheral side of the clutch / deceleration mechanism 4, and the stator is mounted on the outer peripheral side of the rotor 7. 7 is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor used in a washing machine.

[0002]

2. Description of the Related Art FIG.
FIG. 14 is a cross-sectional view of a conventional motor for a washing machine described in Japanese Patent Publication No. 2 and FIG. 14 is a plan view of the motor of FIG. 13 and 14, reference numeral 1 denotes a washing machine outer tub, 2 denotes a washing tub and dewatering tub, 3 denotes a stirring blade, 5 denotes a motor, 6 denotes a stator, which is formed by laminating bow-shaped silicon steel plates. 7 are arranged via a gap. Reference numeral 15 denotes a clutch mechanism, and the motor 5
No mechanism for reducing the number of rotations is provided, and the motor 5 and the clutch mechanism 15 are directly connected. 8 is the clutch mechanism 1
A rotation shaft 5 and an outer shell 9 of the motor are fixed to the outer tub 1. The rotor 7 is arranged on the outer peripheral side of the clutch mechanism 15, uses the same rotating shaft 8, and the arcuate stator 6 is arranged on the outer peripheral side of the rotor 7 via a gap. The stator 6 is formed by laminating a large number of stamped electromagnetic steel sheets,
A coil 14 is wound inside the slot of the stator 6, and generates a magnetic field by flowing an electric current. The rotor 7 is rotated by the generated magnetic field to generate torque.

[0003]

In the conventional motor for a washing machine, since the stator 7 is formed in an arc shape as described above,
If the motor output cannot be increased and the motor is used for a washing machine that requires low speed and high torque during washing and rinsing, the motor size becomes large and the cost increases. Further, since the motor 5 is directly connected to the clutch mechanism 15 and does not have a speed reduction mechanism, the motor needs to generate a high torque, and the motor becomes large in size, which is not suitable for a washing machine. Further, since the stator 7 is not formed in a circular shape, the balance is poor and noise is easily generated. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain a small, highly efficient, and low-cost motor for a washing machine, and to further reduce noise. With the goal.

[0004]

A motor for a washing machine according to the present invention is provided at a lower portion of a washing / cum-drying tub and connected to a stirring blade, and is provided on an outer peripheral side of the speed reducing device. The rotor includes a cylindrical rotor fixed to a rotation shaft of the speed reduction means, and a stator disposed with an air gap on an outer peripheral side of the rotor.

[0005] The rotating shaft of the speed reducing means includes a rotating shaft portion and a fixing portion provided orthogonal to the rotating shaft and fixed to the inner peripheral portion of the rotor by welding.

[0006] Further, a speed reducing means provided at a lower portion of the washing tub and the dewatering tub and connected to the stirring blade, and disposed on the outer peripheral side of the speed reducing means, and a lower end is fixed to a rotating shaft of the speed reducing means. A cylindrical rotor having a bottom portion and a stator disposed with an air gap on the outer peripheral side of the rotor.

The motor for a washing machine according to claim 3, wherein the cylindrical portion of the rotor is formed by stacking ring-shaped silicon steel plates, and the bottom portion is formed by stacking silicon steel plates having holes for fixing a rotating shaft.

The rotor has a magnetic pole projection, and the stator has a magnetic pole projection around which a coil is wound.

Further, the stator is a divided stator.

[0010] Further, an N-pole magnet and an S-pole magnet are alternately provided on the outer periphery of the cylindrical portion.

Further, the rotor is a cage rotor, and a cooling fin is provided on an end ring.

Further, the rotor is a cage rotor, and the cage rotor is provided with an end ring and a cooling fin integrally formed by aluminum die casting.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a main part of a driving device for a washing machine according to Embodiment 1 of the present invention. In FIG.
1 is an outer tub of a washing machine, 2 is a washing tub and dehydration tub (hereinafter abbreviated as a washing tub), 3 is a stirring blade for stirring the laundry inside the washing tub 2, and 4 is a clutch / deceleration mechanism which is a speed reducing means. (Less than,
5 is a motor, 6 is a stator of the motor 5, 7 is a rotor of the motor 5, 8 is a rotating shaft of the clutch / deceleration mechanism 4 and the motor 5, 9 is an outer shell of the motor 5, It is fixed to the outer tank 1.

In FIG. 1, a rotor 7 is arranged on the outer peripheral side of the speed reduction mechanism 4 and uses the same rotation shaft 8 as the speed reduction mechanism 4. The stator 6 is arranged on the outer peripheral side of the rotor 7 via a gap. The stator 6 is formed by laminating a large number of stamped electromagnetic steel sheets. A coil is wound inside the slot of the stator 6 and generates a rotating magnetic field by flowing a current. The rotor 7 is rotated by the generated rotating magnetic field to generate torque. The generated torque of the motor 5 is transmitted to the stirring blade 3 during washing and rinsing via the speed reduction mechanism 4.
During the dehydration, the washing tub 2 and the stirring blade 3 are driven together.

Since the rotor 7 is arranged on the outer peripheral side of the speed reduction mechanism 4, the distance from the rotating shaft 8 (hereinafter, abbreviated as a rotating diameter) becomes long. Since the generated torque of the motor is proportional to the product of the core width and the rotation diameter of the rotor 7, the torque can be increased. That is, if the generated torque is the same, the core width can be reduced because the rotation diameter is large, and the motor 5 can be reduced in the height direction. By making the motor 5 smaller in the height direction, a washing machine having the same capacity can be made compact, and as a result, a low-cost washing machine can be obtained.

The washing machine repeatedly performs forward rotation and reverse rotation during washing and rinsing. Therefore, when switching the rotation direction, the washing machine repeatedly stops and starts, and requires a large starting torque. This method is effective for a washing machine requiring a large torque by increasing the rotation diameter.

As a method of providing the rotor 7 on the outer peripheral side of the speed reduction mechanism 4, there is also a method of directly connecting a motor without using a speed reduction mechanism. In the system using the reduction mechanism 4, for example, the motor 5
The rotation speed of 1500 rpm and the torque of 16 kg-cm are reduced by the reduction mechanism 4 so that the stirring blade 3 is rotated at 130 rpm during washing and rinsing.
Decelerate to m. The required torque at this time is 180k
g-cm. In a direct connection type system that does not use a reduction mechanism, a motor that generates a torque of 180 kg-cm is required, and the motor becomes large. Therefore, for a washing machine, the motor having the speed reduction mechanism 4 is smaller in size than the direct connection type motor, and the total cost can be reduced even if the speed reduction mechanism is added. In this method, by providing a speed reduction mechanism, the generated torque of the motor may be substantially the same as the method using a pulley, and a pulley is not required, so that a low-cost motor for a washing machine can be obtained as a whole.

With the above-described structure, the motor can be reduced in size in the height direction, and a motor for a washing machine with high efficiency, low noise, and low cost can be obtained.

Embodiment 2 Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 2 is a sectional view of the periphery of a speed reduction mechanism 4 of a washing machine according to Embodiment 2 of the present invention.
Is a speed reduction mechanism as a speed reduction means, 7 is a rotor, 8 is a rotation shaft of the speed reduction mechanism 4, 8a is a rotation shaft portion, 8b is a fixed portion, and 10 is an end ring of a cage rotor.

The rotor 7 is a cage rotor made of aluminum die-cast, and has a fixed portion 8b of the rotating shaft 8 of the reduction mechanism 4.
Are fixed to the inner peripheral end face of the rotor 7 by welding. FIG.
In the above, the washing machine repeatedly performs the forward rotation and the reverse rotation during washing and rinsing, and thus repeatedly starts and stops when the rotation direction is switched, and requires a large starting torque. Therefore, when switching from normal rotation to reverse rotation, a large force acts on the contact surface between the rotor 7 and the rotating shaft 8, so that the contact surface needs to maintain strength.

With the above configuration, the contact between the rotor 7 and the rotating shaft 8 is fixed to the fixed portion 8 having a large diameter of the rotating shaft 8.
Since welding is performed at b, the area to be welded is increased, the strength of the contact portion can be maintained, and a highly reliable motor for a washing machine can be obtained. FIG. 3 is another sectional view of the second embodiment of the present invention, in which a fixed portion 8b of the rotating shaft 8 of the speed reduction mechanism 4 and an inner peripheral surface of the rotor 7 are arranged at the center of the rotor 7 in the height direction. Welded. In this method, the vibration of the motor can be more effectively suppressed by supporting the rotating body at a balanced portion, and a low-noise washing machine can be obtained.

Embodiment 3 FIG. An embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a cross-sectional view of the periphery of the speed reduction mechanism 4 of the washing machine according to Embodiment 3 of the present invention. The rotor 7 shown in FIG. Using a steel plate, a silicon steel plate having a small inner diameter is laminated on the lower side and a larger inner diameter is laminated on the upper side, and the diameter of the rotating shaft 8 is made the same as the inner diameter of the lower silicon steel plate. 8 is supported.

At this time, for example, the rotating shaft 8 is pressed into the rotor 7 by using a press or the like, or the rotating shaft 8 is inserted after the rotor 7 is heated and the inner diameter is expanded by heat. The strength of the contact portion between the shaft 7 and the rotating shaft 8 can be maintained. Further, by increasing the number of silicon steel plates having a small inner diameter, the contact area between the rotor 7 and the rotating shaft 8 increases, and the strength of the contact portion can be further enhanced.

Since the rotating shaft 8 is supported by the silicon steel plate constituting the rotor 7 as described above, the working process of supporting the rotating shaft is simplified, and the working can be performed at low cost. it can. That is, a low-cost motor for a washing machine can be obtained.

Embodiment 4 An embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a sectional view of the periphery of a speed reduction mechanism 4 of a washing machine according to Embodiment 4 of the present invention, in which a cooling fin 11 is bonded to an end ring 10 of a rotor 7 shown in FIG. Since the washing machine repeatedly starts and stops,
When a squirrel-cage induction motor is used as a motor, a state in which the secondary current is always large continues. As a result, secondary copper loss increases,
The heat generated by the rotor 7 may affect other mechanisms such as a bearing.

Since the cooling fins 11 are adhered to the end ring 10 to dissipate the heat generated by the rotor 7, the motor loss can be reduced, and high efficiency and high reliability can be obtained. A high washing machine motor can be obtained.

The bonding in this embodiment is for transferring the heat of the end ring 10 to the cooling fins 11, and it is desirable to use a resin having a high heat conductivity or an industrial adhesive as the adhesive.

Embodiment 5 An embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a sectional view of the periphery of the speed reduction mechanism 4 of the washing machine according to Embodiment 5 of the present invention, in which the end ring 10 and the cooling fin 11 shown in FIG. 5 are integrally formed. FIG. 7 is a bottom view of FIG. 6, in which the rotor 7 is provided with a ventilation hole 12 for cooling. When a squirrel-cage induction motor is used as the motor, the rotor generally forms a bar of the secondary conductor and the end ring 10 integrally by laminating a large number of silicon steel plates and then performing aluminum die casting.

With the above configuration, the shape of the end ring 10 on one side is changed to the shape of the cooling fin 11 and die-casting with aluminum is performed.
This eliminates the need for a step of bonding, so that processing can be performed at low cost. That is, a low-cost and high-efficiency washing machine motor can be obtained. In addition, by providing the ventilation holes 12, the heat generated by the rotor 7 can be effectively radiated by effectively utilizing the flow generated by the rotation of the rotor 7, and the washing machine having high efficiency and high reliability can be provided. Motor can be obtained.

Embodiment 6 FIG. An embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a sectional view of a periphery of a speed reduction mechanism 4 of a washing machine according to Embodiment 6 of the present invention, which uses a DC brushless motor in which a magnet 13 is provided on an outer diameter side of a rotor 7 having silicon steel sheets laminated. In addition, the magnet 13 is bonded to the rotor 7. FIG. 9 is a bottom view of FIG. 8 and shows a four-pole DC brushless motor in which four magnets 13 are alternately arranged with N and S poles.

FIG. 10 shows a structure in which the rotating shaft 8 is integrally formed with the rotating steel shaft 8 shown in FIG. 8 and a laminated silicon steel plate. When a DC brushless motor is used, the rotor 7 does not need to be laminated with a silicon steel plate, so that the rotor core can be formed integrally with the rotating shaft 8.

When a squirrel-cage induction motor is used as a motor for a washing machine, the motor often operates at a rotational speed much lower than the synchronous rotational speed, so that slippage is large, secondary copper loss increases and loss increases. There are many.

With the above configuration, the use of a DC brushless motor as a motor makes it possible to control the motor at an arbitrary rotational speed, and to perform the control with high efficiency under all the rotational speed conditions. Therefore, a high-efficiency washing machine motor with reduced loss can be obtained. In addition, the cost of the rotor 7 is reduced, that is, a low-cost washing machine motor can be obtained. In this embodiment, four poles have been described, but the same effect can be obtained with any number of poles. Also, the method of bonding the magnet to the outer diameter side of the rotor has been described. However, the same effect can be obtained by a method in which the magnet is embedded in the rotor or a method in which the magnet and plastic are integrally formed.

Embodiment 7 of the Invention An embodiment of the present invention will be described with reference to the drawings. FIG. 11 shows Embodiment 7 of the present invention.
1 is a cross-sectional view of the vicinity of a clutch / speed reduction mechanism 4 of a washing machine using a reluctance motor having a reluctance iron core. In FIG. 11, the stator 16 is 12
The stator has a plurality of magnetic pole protrusions, and a coil 17 is wound around the magnetic pole protrusions in a concentrated winding. Reference numeral 18 denotes a rotor having eight magnetic pole projections.

As described above, by using a reluctance motor as a motor, the structure of the motor is simplified.
A low-cost motor for a washing machine can be obtained.

In this embodiment, the number of magnetic pole protrusions of the stator 15 and the rotor 16 is 12: 8, but the same effect can be obtained with other numbers.

Embodiment 8 of the Invention An embodiment of the present invention will be described with reference to the drawings. FIG. 12 shows Embodiment 8 of the present invention.
FIG. 9 is a cross-sectional view of the periphery of the speed reduction mechanism 4 of the washing machine according to FIG.
In this embodiment, a stator 19 divided from the sixth embodiment shown in FIG.

As described above, by using the divided stator 6, the coil 14 can be wound around the teeth of the stator 6 in a concentrated manner, so that a highly efficient washing machine motor with reduced copper loss can be obtained. Can be. In addition, the amount of copper can be reduced by the concentrated winding, and the process of performing the winding is facilitated, so that the processing can be performed at low cost. That is, a low-cost motor for a washing machine can be obtained.

Although a DC brushless motor has been described in this embodiment, similar effects can be obtained with other motors.

[0040]

Since the present invention is configured as described above, it has the following effects.

A motor for a washing machine according to the present invention is provided with a speed reducer provided at a lower portion of a washing tub and a dewatering tub and connected to a stirring blade, and is disposed on an outer peripheral side of the speed reducer, and a rotating shaft of the speed reducer is provided. Since the motor has a cylindrical rotor fixed to the motor and a stator arranged with an air gap around the outer periphery of the rotor, the motor becomes smaller in the height direction and lower cost is realized. it can.

Further, the rotating shaft of the speed reduction means includes a rotating shaft portion and a fixed portion provided orthogonal to the rotating shaft and fixed to the inner peripheral portion of the rotor by welding. And a highly reliable motor can be obtained.

A deceleration means provided at a lower portion of the washing / dewatering tub and connected to the agitating blades, and is disposed on an outer peripheral side of the deceleration means, and a lower end is fixed to a rotating shaft of the deceleration means. The motor has a small size in the height direction and a low cost because it has a cylindrical rotor with a bottom and a stator arranged with an air gap on the outer circumference of the rotor. it can.

Further, since the cylindrical portion of the rotor is formed by laminating a ring-shaped silicon steel plate and the bottom portion is formed by laminating a silicon steel plate having a hole for fixing the rotation shaft, the process of supporting the rotation shaft is simplified, and the cost is reduced. Can be realized. Further, by increasing the number of silicon steel plates to be supported, the strength of the contact portion can be maintained, and a highly reliable motor can be obtained.

Further, since the rotor has the magnetic pole projections and the stator has the magnetic pole projections on which the coils are wound, the structure of the motor is simplified and the cost can be reduced.

Also, since the stator is a divided stator, high efficiency and energy saving can be realized.

Further, since N-pole magnets and S-pole magnets are alternately provided on the outer periphery of the cylindrical portion, high-efficiency control can be performed at all rotation speeds, and energy saving can be realized. Further, by integrally molding the rotor core and the rotating shaft, cost reduction can be realized.

Further, since the rotor is a cage rotor and the end fins are provided with cooling fins, the heat of the rotor can be dissipated and a highly reliable motor can be obtained.

Further, since the rotor is a cage rotor, and the cage rotor is provided with an end ring and cooling fins integrally formed by aluminum die-casting, the end ring has a cooling fin shape. Thereby, processing can be performed at low cost. In addition, by providing the rotor with a vent hole, heat can be effectively radiated from the rotor, and a highly reliable motor can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a driving device of a washing machine according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view around a speed reduction mechanism of a washing machine according to Embodiment 2 of the present invention.

FIG. 3 is a cross-sectional view around a speed reduction mechanism of a washing machine according to Embodiment 3 of the present invention.

FIG. 4 is a cross-sectional view around a speed reduction mechanism of a washing machine according to Embodiment 3 of the present invention.

FIG. 5 is a sectional view around a speed reduction mechanism of a washing machine according to Embodiment 4 of the present invention.

FIG. 6 is a sectional view around a speed reduction mechanism of a washing machine according to Embodiment 5 of the present invention.

FIG. 7 is a bottom view around a speed reduction mechanism of a washing machine according to Embodiment 5 of the present invention.

FIG. 8 is a sectional view around a speed reduction mechanism of a washing machine according to Embodiment 6 of the present invention.

FIG. 9 is a bottom view around the speed reduction mechanism of the washing machine according to Embodiment 6 of the present invention.

FIG. 10 is a sectional view around a speed reduction mechanism of a washing machine according to Embodiment 6 of the present invention.

FIG. 11 is a plan view around a speed reduction mechanism of a washing machine according to Embodiment 7 of the present invention.

FIG. 12 is a plan view around a speed reduction mechanism of a washing machine according to Embodiment 8 of the present invention.

FIG. 13 is a sectional view of a driving device of a conventional washing machine.

FIG. 14 is a plan view of a conventional washing machine motor.

[Explanation of symbols]

1 outer tub of washing machine, 2 washing tub and dewatering tub, 3 stirring blade, 4
Clutch / reduction mechanism, 5 motors, 6, 16, 19
Stator, 7, 18 rotor, 8 rotation axis, 10 end ring, 11 cooling fin, 12 vent, 13 magnet,
17 coils, 15 clutch mechanism.

Claims (9)

[Claims] A speed reducer provided at a lower portion of the washing / dewatering tub and connected to a stirring blade; and a cylindrical rotation fixed to a rotating shaft of the speed reducer and disposed on an outer peripheral side of the speed reducer. A motor for a washing machine, comprising: a rotor; and a stator disposed with an air gap on an outer peripheral side of the rotor. 2. The rotation shaft of the speed reduction means includes a rotation shaft portion, and a fixing portion provided orthogonal to the rotation shaft and fixed to an inner peripheral portion of the rotor by welding. 2. The motor for a washing machine according to 1. 3. A deceleration means provided at a lower portion of the washing / dewatering tub and connected to a stirring blade, and is disposed on an outer peripheral side of the deceleration means, and a lower end is fixed to a rotating shaft of the deceleration means. A motor for a washing machine, comprising: a cylindrical rotor having a bottom portion; and a stator disposed with an air gap on an outer peripheral side of the rotor. 4. The motor for a washing machine according to claim 3, wherein the cylindrical portion of the rotor is formed by stacking ring-shaped silicon steel plates, and the bottom portion is formed by stacking silicon steel plates having holes for fixing a rotation shaft. 5. The motor for a washing machine according to claim 1, wherein the rotor has a magnetic pole projection, and the stator has a magnetic pole projection wound with a coil. 6. The motor for a washing machine according to claim 1, wherein the stator is a divided stator. 7. The washing machine motor according to claim 1, wherein N-pole magnets and S-pole magnets are alternately provided on the outer periphery of the cylindrical portion. 8. The motor for a washing machine according to claim 1, wherein the rotor is a cage rotor, and a cooling fin is provided on an end ring. 9. The washing machine according to claim 1, wherein the rotor is a cage rotor, and the cage rotor is provided with an end ring and a cooling fin integrally formed by die-casting with aluminum. For motor.