JP2002035467A - Electric washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric washing machine with a simple structure and produced at a low cost. SOLUTION: An electric motor 64 for driving a washing/drying tub 60 in washing has windings 80-82 changing each of inductances according to rotation, allowing differences of winding current values of the motor in the washing/ drying to be restrained, ohmic losses of the windings in the washing to be decreased, and a switching element having a smaller rated current to be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric washing machine used in ordinary households and the like.

[0002]

2. Description of the Related Art FIG. 14 shows the configuration of a conventional washing machine of this type.

[0003] As shown in FIG.
A plurality of small holes are provided on the inner wall surface, a stirring blade 2 is rotatably arranged on the bottom surface, and a water receiving tank 3 is provided outside the washing and dewatering tank 1. A drive unit 4 for driving the washing / dewatering tub 1 and the stirring blade 2 is provided on the bottom surface of the water receiving tank 3, and the drive unit 4 has a speed reducer 5 having a reduction ratio of 1/6 by a planetary gear. .

The speed reducer 5 also has a clutch function so as to drive the washing / dewatering tub 1 or the stirring blade 2.

[0005] The water receiving tank 3 is supported on the outer frame 6 through four suspensions 7 by vibration isolation. A waterway cover 8 is fixed to the inner wall of the washing and dewatering tub 1 to form a circulation waterway 9, and the circulation waterway 9 is provided with a lower blade 10 integrally provided on the back surface of the stirring blade 2.
A pump chamber 11 formed on the outer periphery and a lint filter 12 on the upper part of the washing and dewatering tub 1 are connected.

A fluid balancer 13 containing a liquid is fixed above the washing / dewatering tub 1. The upper surface of the water receiving tank 3 is covered with a water receiving tank cover 14. Here, packing (not shown) or the like is interposed between the water receiving tank 3 and the water receiving tank cover 14 to ensure water tightness. The washing and dewatering tub 1 is provided on the lower surface of the water receiving tub cover 14.
A rectifying member 15 is provided toward a substantially rotation center of the rectifying member.

The drain valve 16 drains the washing water in the water receiving tub 3, and the water supply valve 17 supplies water into the water receiving tub 3.

By controlling the operation of the driving means 4, the drain valve 16, the water supply valve 17 and the like, a series of washing, rinsing, and dehydrating steps can be sequentially performed.

When washing the perishable laundry, the washing and dewatering tub 1 is rotated at, for example, 150 rpm in each of the washing and rinsing steps.
By rotating the pump, the washing liquid between the washing and dewatering tub 1 and the water receiving tub 3 is moved from between the washing and dewatering tub 1 and the water receiving tub cover 14 to approximately the center of rotation of the washing and dewatering tub 1. It is configured to discharge toward.

The drive means 4 is transmitted from the electric motor 18 to the speed reducer 5 via the belt 19, and during this time, the drive means 4
It has a reduction ratio of.

A flow regulating rib 20 is provided on the inner surface of the bottom of the water receiving tank 3 by resin molding.

FIG. 15 is a circuit diagram for driving the electric motor 18.

In FIG. 15, the electric motor 18 has a winding 2
1, 2, and 23 are three phases, and have permanent magnets 24 and 25 movably provided.

The DC power supply 26 comprises an AC power supply 27 of 100 V 60 Hz, a choke coil 28, and a rectifier circuit 29. The rectifier circuit 29 includes four diodes 30,
A full-wave rectifier having a bridge connection of 31, 32 and 33 is used.

An output of the DC power supply 26 is connected to an inverter circuit 34 of three phases and six stones, and an electrolytic capacitor 35 is connected between input terminals of the inverter circuit 34.

The switching elements 40, 41, 42, 43, 44 and 45 in the inverter circuit 34 are all IG
It is composed of a BT and a diode connected in anti-parallel to the BT.

These diodes all pass a current in the reverse direction immediately after switching of the switching elements 40, 41, 42, 43, 44, 45.

The windings 21, 22, and 23 of the motor 1 are connected in a so-called star connection, and one terminal of each winding is an input terminal 46, 47, and 48.

The control circuit 49 includes a switching element 40,
It is connected to each of the gate terminals 41, 42, 43, 44, and 45, and controls on / off of each switching element.

The Hall IC 5 provided in the motor 18
Numerals 0, 51, and 52 constitute position detecting means for detecting whether the opposing magnetic poles are N poles or S poles by the rotation of the permanent magnets 24, 25, and thereby outputting a high and low logic signal to the control circuit. 49 to cause the control circuit 49 to operate.

FIG. 16 is a waveform diagram showing the output signal waveforms of the Hall ICs 50, 51 and 52.
Is provided, a signal change from high to low or from low to high occurs sequentially every electrical angle of 60 degrees, and the position detection signal is transmitted to the control circuit 49.

Here, the windings 21, 22, 23 of the electric motor 1
Have a substantially constant self-inductance even when rotated, and the mutual inductance between the two windings is smaller than the self-inductance, but the change due to rotation is also small.

Accordingly, a force (torque) according to the Fleming's left-hand rule acts on the permanent magnets 24 and 25, and the permanent magnets 24 and 25 operate as an electric motor of a type generally called a brushless DC motor or the like.

The operation as an electric washing machine will be described. When laundry is put in the washing and dewatering tub 1 and the washing and dewatering tub 1 is rotated in the washing liquid, the water receiving tub 3 is centrifugally generated by the rotation. The washing liquid is straightened by the straightening ribs 20 on the inner surface of the washing machine.

In this case, the speed reducer 5 is in a directly connected state, and operates only by １ ／ reduction by the belt 19.

FIG. 17 is a diagram showing a detailed configuration of the inner surface of the bottom of the water receiving tank 3, and shows an example of the rectifying rib 20.

Due to the rectifying action of the rectifying ribs 20, a more upward movement is generated, and the rotating washing and dewatering tub 1 is rotated.
The liquid is separated from the liquid layer of the washing liquid rotating in conjunction with the flow by the rectifying member 15 and discharged from the space between the washing and dewatering tub 1 and the water receiving tub cover 14 toward a substantially rotation center in the washing and dewatering tub 1. Can be.

Therefore, regardless of the quality or quantity of the laundry in the washing and dewatering tub 1, the washing liquid is discharged stably and in a well-balanced manner to the substantially rotation center of the washing and dewatering tub 1,
The washing liquid can be circulated throughout the laundry, so that the laundry can be washed without being damaged or entangled, and without unevenness in washing.

Regarding the operation during dewatering, first, the drain valve 16 is opened, and the water in the washing and dewatering tub 1 is almost drained from the drain valve 16 by the gravity of the earth.
The washing and dewatering tub 1 is also rotated by the driving means 4,
A centrifugal force is applied to the laundry containing water, and the water is further separated and drained from the drain valve 16.

At the time of spin-drying, the speed reducer 5 is operated in a directly connected state, and the speed of the washing and spin-drying tub 1 is reduced to 88 / min.
By increasing the rotation to zero rotation, the laundry can be sufficiently dehydrated.

At the time of washing, the stirring blades 2 are effective for removing severe dirt in a short time and for correcting unevenness of the laundry before dehydration. Rotation is also performed.

The rotation axis of the stirring blade 2 is
Since the output is connected to the output decelerated to / 6, the stirring blades 2 are driven to rotate by low-speed and high-torque power.

[0033]

In the prior art described above, the washing and dewatering tub 1 is rotated both during washing and during dehydration, and the speed reducer 5 is directly connected to each other. However, the required torque and speed are greatly different between washing and dehydrating.

That is, when compared with the axis of the washing and dewatering tub 1, the speed is about 150 N / min and 4 Nm per minute during the washing, but is about 880 N / min and about 0.5 Nm during the dehydration.

The electric motor 18 generates torque by the interaction between the magnetic flux generated from the permanent magnets 24 and 25 and the current supplied to the windings 21, 22 and 23.
The value obtained by multiplying the current value by the value of the interlinkage magnetic flux of the permanent magnets 24 and 25 was the torque.

However, on the other hand, an induced electromotive force proportional to a value obtained by multiplying the value of the interlinkage magnetic flux by the rotation speed is generated in the windings 21, 22, and 23.
It is necessary to supply electric power of a voltage higher than the induced electromotive force.

That is, since the value of the linkage magnetic flux of the permanent magnets 24 and 25 is constant, the value of the induced electromotive force with respect to the speed and the value of the torque with respect to the current are always substantially constant.

Therefore, for example, the windings 2 are so arranged that the induced electromotive force does not become excessive even at 880 revolutions per minute during dehydration.
The number of turns of 1, 22, and 23 is designed so that the value of the interlinkage magnetic flux is suppressed, that is, the value of torque (torque constant) with respect to current becomes a small value.

Therefore, there is a problem that a large current is required to generate a large torque during washing using centrifugal force.

For this reason, the copper loss of the windings 21, 22, and 23 during washing is larger than that during dehydration, and the peak value of the current flowing through the switching elements 40 to 45 constituting the inverter circuit 34 is also large. Also, the current rating of each switching element needs to be large so that it can cope with washing, and the cost is high.

[0041]

According to the present invention, there is provided a washing and dewatering tub, and a driving means for driving a rotating shaft of the washing and dewatering tub. The driving unit includes a motor having a winding whose inductance changes according to a rotation angle, and an inverter circuit, wherein the inverter circuit includes a DC power supply, a switching element, and a control circuit for turning on and off the switching element. As a result, it is possible to improve an increase in current at the time of high torque (a winding current proportional to the torque is required), as in the case of using a motor that generates power only by the interaction between the permanent magnet and the winding current, and to reduce the speed at high speed. In the torque range, it is possible to obtain the characteristic that the magnitude of the winding current with respect to the torque is suppressed. With reducing, suppressing the peak value of the current flowing through the switching device constituting the inverter Ichita circuit, and realizes a low cost as possible the use of smaller switching element having a current rating.

[0042]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention has a washing and dewatering tub and a driving means for driving a rotating shaft of the washing and dewatering tub, The driving means includes a motor having a winding whose inductance changes according to a rotation angle, and an inverter circuit, and the inverter circuit supplies power to the DC power supply and the winding intermittently in synchronization with the motor. By providing a switching element and a control circuit for turning the switching element on during the increase period of the inductance, the induced electromotive force generated at high speed is suppressed to achieve good power supply even during dehydration, and high torque is provided. It supplies a large torque generated by a change in inductance even when washing is necessary, suppresses winding current, suppresses copper loss, and is a component of the inverter circuit. Current rating of the switching element is also suppressed, it is an inexpensive.

According to a second aspect of the present invention, there is provided the electric washing machine according to the first aspect, further comprising a liquid supply means for supplying a washing liquid to the inside of the washing and dewatering tub during washing. Since the washing liquid received from the supply means is re-separated from the object to be washed by centrifugal force, the winding current is also suppressed, and washing with less entanglement and damage to the object to be washed can be performed.

According to a third aspect of the present invention, there is provided an electric washing machine according to the second aspect, wherein the liquid supply means includes a water receiving tank and a water receiving tank cover, and the washing and dewatering tank is provided in the water receiving tank. The washing / dewatering tub cover is disposed rotatably. The water receiving tub cover covers the upper part of the water receiving tub. The liquid is supplied from the washing and spin-drying tub and the water receiving tub cover toward the rotation center of the washing and spin-drying tub. The present invention realizes an electric washing machine having high washing performance by performing the passage washing in which a large amount of washing liquid is circulated.

According to a fourth aspect of the present invention, the electric motor of the electric washing machine according to any one of the first to third aspects is configured to have a permanent magnet, so that the torque and inductance of the permanent magnet are reduced. By generating both torques due to the change, the winding current is also suppressed, and the configuration is slightly complicated, but the power can be efficiently supplied in both the washing operation and the dehydrating operation. This is to realize a washing machine.

According to a fifth aspect of the present invention, the electric motor of the electric washing machine according to any one of the first to fourth aspects is driven while being directly connected to the shaft of the washing and dewatering tub. With the configuration, the winding current is also suppressed, and an electric washing machine having a simple configuration without a reduction gear is realized.

According to a sixth aspect of the present invention, there is provided the electric washing machine according to any one of the first to fifth aspects, further comprising a stirring blade and a clutch, wherein the stirring blade is provided on a bottom surface of the washing and dewatering tub. Provided inside, the clutch switches rotation transmission from the electric motor to the washing and dewatering tub, and the electric motor drives only the stirring blade when the clutch is off, and when the clutch is on, By driving the washing and dewatering tub together with the stirring blades, it is possible to perform washing with the stirring blades that require a particularly large torque, and in the case of severely soiled laundry, electricity can be dropped in a short time. A washing machine is provided.

Further, the invention according to claim 7 has a washing and dewatering tub, a stirring blade disposed at the bottom of the washing and dewatering tub, and a drive means for driving a rotating shaft of the washing and dewatering tub and the stirring blade. The driving means includes: a motor having a winding whose inductance changes according to a rotation angle; a clutch for switching rotation transmission from the motor to the washing and dewatering tub; and an inverter circuit. A switching element for supplying power to the DC power supply and the windings intermittently in synchronization with a motor, and a control circuit for turning on the switching element during an increase period of the inductance. When the clutch is turned off, the stirring blades are driven to rotate, and at the time of dehydration, the clutch is turned on and the washing and dewatering tub is driven to rotate together with the stirring blades. With a simple configuration that does not use permanent magnets, the ratio of the supply current of the winding at each operating point of torque and speed during washing and dehydration is suppressed, the copper loss of the winding is suppressed, and the switching element required This realizes an electric washing machine with a reduced current rating.

[0049]

Next, specific examples of the present invention will be described.

(Embodiment 1) FIG. 1 is a sectional view of Embodiment 1 of the present invention.

As shown in FIG. 1, the washing and dewatering tub 60 is
A number of small holes are provided on the inner wall surface, and a stirring blade 61 is rotatably arranged on the bottom surface.
2 and a washing and dewatering tub 60 is rotatably disposed in a water receiving tub 62.

A washing and dewatering tank 6 is provided on the bottom of the water receiving tank 62.
A drive means 63 for driving the agitating blade 61 is provided. The drive means 63 has an electric motor 64 coaxially with the washing and dewatering tub 60.

The water receiving tank 62 is supported on the outer frame 65 via a suspension 66 in a vibration-proof manner. A waterway cover 67 is fixed to the inner wall of the washing and dewatering tub 60 to form a circulation waterway 68,
The circulation channel 68 connects between a pump chamber 70 formed on the outer periphery of a lower blade 69 provided integrally on the back surface of the stirring blade 61 and a lint filter 71 on the upper part of the washing and dewatering tub 20.

A fluid balancer 72 containing a liquid is fixed above the washing / dehydrating tub 60. Water receiving tank 62
Is covered with a water receiving tank cover 73. Here, packing (not shown) is interposed between the water receiving tank 62 and the water receiving tank cover 73 to ensure water tightness. A rectifying member 74 is provided on the lower surface of the water receiving tub cover 73 so as to be substantially at the center of rotation of the washing and dewatering tub 60.

In this embodiment, the driving means 63 is provided with a clutch 75, and the electric motor 64 drives only the stirring blade 61 when the clutch 75 is off.
Is on, the washing and dewatering tub 60 together with the stirring blade 61
It is driven in a state where it is directly connected to the axis.

The drain valve 76 drains the washing water in the water receiving tank 62, and the water supply valve 77 supplies water to the water receiving tank 62.

Although the driving means 63 includes an inverter circuit, it is not shown in FIG. 1 and will be described later in detail with reference to a circuit diagram.

In the present embodiment, the water receiving tank 62, the lower blade 69, the pump chamber 70, the water receiving tank cover 73, and the rectifying member 74 are components of the liquid supply means. Therefore, by realizing the liquid supply means with a relatively simple configuration, there is an effect that a low-cost electric washing machine is realized.

In the operation of the electric washing machine, a series of steps of washing, rinsing, and dewatering are sequentially performed by controlling the operations of the driving means 63, the drain valve 76, the water supply valve 77, and the like. .

When washing perishable laundry, the washing and dewatering tub 60 is placed in each step of washing and rinsing.
The washing and dewatering tub 60 is rotated at 50 rpm, and the washing and dewatering tub 60 is rotated by the pump action. The washing and dewatering tub 60 is discharged from the space toward the center of rotation.

FIG. 2 is a circuit diagram showing the inside of the driving means 63 of the first embodiment.

In FIG. 2, a motor 64 and an inverter circuit 80 for supplying a current to the motor 64 are provided.
The electric motor 64 has windings 80, 81, 82 whose inductance changes according to the rotation, and a position detecting means 83 for optically detecting the angle of the rotation.

The inverter circuit 80 is composed of switching elements 84 to 89 constituted by IGBTs, a diode 90
95, a control circuit 96, and a DC power supply 99. The control circuit 96 controls on / off of the switching elements 84 to 89 in accordance with a position detection signal from the position detection means 83, and a rotor in the electric motor 64. 100 to create torque,
It is driven to rotate.

FIG. 3 shows a configuration diagram of the electric motor 64 according to the first embodiment. The configuration of the stator core 101 and the rotor core 102 is such that the number of teeth 103 of the stator core is six. Two small teeth 104a for one tooth 103,
104b, that is, the total number of small teeth is 12
This number is twice the number 6 of the teeth of the stator core 101, that is, an integer multiple.

The number of teeth 105 of the rotor core is ten.

The coils 106 to 111 are formed by winding an enameled wire.

In this embodiment, the teeth 1 of the iron core of the stator are used.
The intervals at the center of 03, that is, the intervals between the coils 106 to 111 are all equal intervals at a mechanical angle of 60 degrees, and all are wound around teeth of the iron core 101 of the stator.

FIG. 4 is a connection diagram of the electric motor 64 according to the first embodiment.

The winding 80 is formed by connecting the coils 106 and 109 in series, the winding 81 is formed by connecting the coils 107 and 110 in series, and the winding 82 is formed by the coils 108 and 1
11 are connected in series.

A black circle attached to one of the coils indicates the polarity of the coil. When current is supplied from the terminal with the black circle to each coil,
This indicates that an N pole is generated in a portion facing the rotor.

Therefore, for example, U1
When current is supplied from the terminals, the coils 106, 1
09 flows through the coil 106, and a current flows from the terminal indicated by the black circle.
Generates an S pole.

Therefore, in the present embodiment, a magnetic path passing substantially through the center of the rotor 102 is formed.

In this embodiment, when the electric motor 64 is rotated from the outside, the self-inductance of the windings 80, 81 and 82 changes, and the motor has the characteristic that the self-inductance changes.
For example, in the state shown in FIG. 3, the self-inductance value of the U-phase winding 80 becomes maximum, and the V-phase winding 81 and W
The phase winding 82 has a considerably lower value than that of the U phase because the overlap between the rotor and stator teeth is small, and furthermore, the self inductance value in a state where the teeth are completely different from each other. Is the lowest, so that the inductance of each of the windings 80, 81, 82 changes in accordance with the rotation angle.

Accordingly, the current is supplied from the inverter circuit 80 to the phase winding whose self-inductance value is increasing by the position detecting means 83, so that the windings 80, 81, Reluctance torque is generated from one of the currents 82, and as a result, the motor functions as an electric motor.

In the first embodiment, the small teeth 104
Since the motors a and 104b are provided, the electric motor 64 mechanically makes 1/10 rotation during a period of one electrical cycle.

FIG. 5 is a configuration diagram of a cross section of a main part near the clutch 75 of the first embodiment.

As shown in FIG. 5, a hollow washing and dewatering tub shaft 116 fixed to the washing and dewatering tub 60 and having an engagement portion 115 at an end thereof, and an outer periphery of the stirring blade shaft 117 are displaced in the thrust direction to form an end. It has a plunger 119 provided with a drive portion 118 that engages with the meshing portion 115, and a solenoid 120 that disconnects the washing / dewatering tub shaft 116 and the stirring blade shaft 117 via the plunger 119.

In the clutch 75 having the above structure, the plunger 119 is displaced upward by energizing the solenoid 120 at the time of spin-drying and at the time of washing using centrifugal force, and the driving portion 118 at the end of the plunger spins. The meshing portion 115 at the end of the shaft is brought into horizontal contact with the meshing portion 115 and meshes with the shaft.
6 and the stirring blade shaft 117 are connected. During the washing and rinsing operations in which only the stirring blade 61 is rotationally driven, the solenoid 120 is not energized, the plunger 119 moves downward by its own weight, and the driving unit 118 at the end of the plunger and the driving unit 118 at the end of the dehydrating shaft. The engagement with the engagement portion 115 is released, and the connection between the washing and dewatering tub shaft 116 and the stirring blade shaft 117 is released.

Reference numeral 121 denotes a bearing, 122 denotes a metal bearing, 123 denotes a serration, and 64 denotes an electric motor.

The operation of the above construction will be described. When the laundry is put in the washing and dewatering tub 60 and the washing and dewatering tub 60 is rotated in the washing liquid, the inner surface of the water receiving tub 62 is centrifugally generated by the rotation. The washing liquid is rectified by the rectifying ribs 20 (a configuration equivalent to that shown in FIG. 17 shown in the prior art), so that a more upward movement occurs, and the washing liquid that rotates in conjunction with the rotating washing and dewatering tub 60 is rotated. It can be separated from the liquid layer by the rectifying member 74 and discharged from the space between the washing and dewatering tub 60 and the water receiving tub cover 73 toward a substantially rotation center in the washing and dewatering tub 60.

Therefore, during the washing, the liquid supply means supplies the washing liquid to the inside of the washing and dewatering tub 60, and the laundry is again separated from the laundry by the centrifugal force of the washing liquid received from the liquid supply means. It is configured to perform the passage cleaning.

Accordingly, irrespective of the quality or quantity of the laundry in the washing and dewatering tub 60, the center of rotation of the washing and dewatering tub 60 may be eccentric with respect to the water receiving tub 62 or may be misaligned during manufacturing. , Water receiving tank cover 73 and fluid balancer 7
Even if the interval between the two becomes uneven, the washing liquid can be stably and well-balanced and discharged to substantially the center of rotation of the washing and dewatering tub 60 to circulate the washing liquid throughout the laundry.
In particular, since the electric motor of the driving means operates efficiently, the consumed electric energy is small,
And without damaging or tangling the laundry,
It can be washed without uneven washing.

FIG. 6 shows the relationship between torque and speed at the shaft of the electric motor 64 according to the first embodiment.

In FIG. 6, X is an operating point when washing is performed using centrifugal force, Y is an operating point when spinning is performed, and Z is an operating point when only the stirring blade 61 is rotated.

The point Z at which only the stirring blade 61 is rotationally driven is that the clutch 75 is turned on and the washing and dewatering tub 60 is rotationally driven together with the stirring blade 61, and the apparatus has a very simple configuration without using a reduction gear. This is a simple motor configuration that does not require permanent magnets.

In the first embodiment, the speed of the agitating blade 61 or the speed of the washing and dewatering tub 60 and the speed of the electric motor 64 are the same because they are directly connected, and the torque is also the same.

The solid line curve shows the relationship between the drive torque and the speed of the motor 64 of the type called a so-called switch reluctance motor used in the present embodiment. It has the characteristic of connecting high torque.

The motor 64 of this embodiment is designed to slightly exceed the Y point and the Z point, so that the operation is ensured even when the voltage of the commercial power supply 31 is slightly reduced. .

It is to be noted that by adjusting the conduction ratio (on duty) of the switching elements 84 to 89, the motor 6
From the curve of the solid line, which is the characteristic of No. 4, there is a degree of freedom to use with the reduced characteristic, and it is possible to control to a desired speed or torque.

In the operation at the point X, the conduction ratio is set to about 60
%, A good washing operation utilizing centrifugal force can be performed.

Incidentally, the dashed curve shows an example of the characteristics of a conventional motor configuration using only permanent magnets. In order to realize an operation of 880 revolutions per minute during dehydration, At points X and Z, the conduction ratio is considerably reduced. On the other hand, the current value supplied to the winding and the peak current value of each switching element become considerably high. In this case, the copper loss of the winding of the motor becomes large, and it is necessary to use an expensive switching element having a large rated current capacity.

The ratio of the supply current of the winding at each of the operating points of the torque and the speed at the time of washing at either the point X or the point Z and the dehydration at the point Y is suppressed, and the copper loss of the winding and the switching element It is intended to realize an electric washing machine in which a required current rating is suppressed.

In the present embodiment, the liquid supply means has a water receiving tank 62 and a water receiving tank cover 73, and uses a pump action generated by rotating the washing and dewatering tank 60. Although it is not particularly necessary to have such a configuration, for example, using a small electric pump,
Even in the case where water is circulated and sprayed again from the center of the washing and dewatering tub 60 to the laundry, the effect of suppressing damage to the laundry and reducing tangling can be obtained.

Further, the liquid supply means may be configured to be sprayed into the washing and dewatering tub 60 in the form of a mist.
When the rotation speed at the time of washing is set to, for example, about 880 to 900 rotations per minute and a higher speed compared to this embodiment,
A strong acceleration (gravitational force) acts to reduce dirt in the interstices of the fibers, thereby obtaining good washing performance. At that time, a low torque is required.

When such a mist-like washing liquid is supplied, the diameter of water droplets is as fine as 10 to 90 micrometers, and can be sprayed in a jet shape at a speed of about 20 meters per second. Then, since the surface area of the mist reaches 10,000 times, the effect of penetrating dirt from the surface of the water droplets and the residue of the detergent (during rinsing) becomes very high.

The washing liquid once separated from the laundry by the centrifugal force may be drained as it is without being circulated, and it is possible to prevent the dropped dirt from returning to the laundry again.

Further, the washing may be performed by rotating the washing and dehydrating tub 60 in a state where the washing liquid and the article to be washed are put in the washing and dewatering tub 60 without providing the liquid supply means. In this case, the required torque is considerably large. The speed is low compared to the time of dehydration, which is a condition of low speed and high torque.However, by using a reluctance type motor, washing current can be realized while suppressing winding current, copper loss, and switching The current rating of the element can also be realized with a small value.

In addition to the switch reluctance type used in the present embodiment, the cylindrical rotor has an axially laminated structure inside, so that the magnetic resistance is changed. The winding may be configured as a distributed winding, which is often found in induction motors,
Even if there is no permanent magnet, if the self-inductance or mutual inductance changes depending on the angle of rotation, reluctance torque will be generated by supplying current to the windings, and low-speed and high-torque operating conditions and high-speed and low-torque operation To reduce the ratio of winding current under the conditions,
The same effect can be obtained.

In the configuration in which the liquid supply means is not provided and the laundry to be immersed in the washing liquid is washed by rotating the washing and dewatering tub 60, the washing and dewatering is performed as compared with the washing method in which only the stirring blade is rotated. Since the surface area of the inside of the water tank 60 is about 7 times as large, the unevenness in washing can be reduced as compared with the stirring blade 61 alone. Can be realized.

Although the washing and dewatering tub 60 of this embodiment has a large number of holes having a diameter of 6 mm, it may have a structure without holes. By rotating while the laundry is soaked, washing is the same, for example, by accelerating the washing and dewatering tub 60 up to 180 rotations per minute, by repeatedly performing left and right alternate rotation directions, Good washing performance can be obtained with effects such as shaking, tapping, and pushing.

By providing the washing and dewatering tub 60 without holes, not only water can be saved, but also the effect of suppressing damage to the laundry during dehydration can be improved.

By using the reluctance type motor, even if the washing and dewatering tub 60 is accelerated from a stationary state to 180 rotations per minute within 0.5 seconds, the winding and dewatering can be performed. The peak value of the current can be set to within about 4 A. Even with a switching element having a small current capacity, a sufficient washing effect can be obtained, and the amount of cloth involved is greatly reduced as compared with washing with the stirring blade 61 alone. Can be done.

(Embodiment 2) FIG. 7 is a configuration diagram of an electric motor 64 according to Embodiment 2, and the other configuration is completely the same as that of Embodiment 1.

In FIG. 7, the configuration of the stator iron core 130 and the rotor iron core 131 is six, and the number of teeth 132 of the stator iron core is six.
The number of teeth 133 of the rotor core is four.

Also in this embodiment, the intervals between the centers of the teeth of the stator core, that is, the intervals between the coils 106 to 111 are all equal intervals having a mechanical angle of 60 degrees.

The connection diagram of the motor 64 of the second embodiment is the same as that of FIG. 4 of the first embodiment.

Also in the present embodiment, since the self-inductance of each winding changes due to the rotational movement of the motor 64, reluctance torque is generated by the current of each winding, and It works.

In this embodiment, since the electric motor 64 mechanically makes a 1/4 turn during a period of one electrical cycle, the frequency is lower than that of the first embodiment.

Therefore, the switching loss of the switching elements 84 to 89 of the inverter circuit 80 can be suppressed lower than in the first embodiment, and the iron loss can be reduced.

(Embodiment 3) FIG. 8 is a sectional view of an electric washing machine according to Embodiment 3 of the present invention. An inverter circuit (not shown in FIG. 8) (not shown in FIG. Although the configuration of the driving means 140 including the details is different from that of the first embodiment, the configuration of the other parts is realized by a configuration completely equivalent to that of the first embodiment. is there.

The driving means 140 according to the present embodiment comprises the electric motor 14
1 and a speed reducer 142.

FIG. 9 shows a detailed configuration diagram of a main part centering on the speed reducer 142.

In FIG. 9, a sun gear 144 and planetary gears 145, 146, and 14 are mounted on a shaft 143 of a motor 141.
7, a case 148 with an internal gear cut, and a speed reduction mechanism 142 having a ring 149 are connected.

A stirring blade 61 is connected to the ring 149, and a washing and dewatering tub 60 is coaxially connected to the case 148.

At the time of washing using only the stirring blade 61,
Although not shown, the case 148 is fixed in the rotational direction by the brake means, and the shaft 1 of the electric motor 141 is fixed.
When the sun gear 144 is rotated by 43, the planetary gear 1
45, 146, and 147 perform revolving motions, and a ring 149 connecting the center axes of the respective planetary gears is connected to the sun gear 1.
The speed is reduced to 1/6 of the speed of 44 and the washing blade 150 is rotated to rotate the stirring blade 61 from the washing shaft 150.

On the other hand, during dehydration, the case 148 is rotatable (not shown), and the case 148 is rotated by the clutch mechanism (not shown).
And the agitating blade 61 and the washing and dewatering tub 60 are both directly connected to the output shaft 143 of the electric motor 141, and are all rotationally driven at the same speed. It will be.

During the spin-drying and the spinning of the washing and dewatering tub 60, the washing and dewatering tub 60 and the stirring blade 61 are both directly connected to the shaft 143 of the electric motor 141. Appears as it is,
At the time of washing with only the stirring blade 61, the speed reducer 142
Of the motor 1
This is six times the value supplied from 41.

Therefore, even when driving the stirring blade 61 requiring a large torque, the supply torque from the electric motor 141 can be reduced to 1/6.

However, the speed is six times that of the stirring blade 61, but according to the experiments by the inventors, the stirring blade 61
However, at a speed of 150 revolutions per minute, almost sufficient washing performance can be obtained. Therefore, the speed of 900 revolutions per minute, which is six times that of the above, is almost the same as the speed of the washing and dewatering tub 60 at the time of spin-drying, so that The motor 141 can be designed, and as a result, a small motor 141 with a small torque can be used, so that the motor 141 can be reduced in size and cost, and an extremely practical configuration can be achieved even with the reduction gear 142 in total. It becomes.

In this embodiment, the speed reducer 142
Is set to 1/6, but this value is not necessarily required.

The structure of the speed reducer 142 is not limited to the structure of the present embodiment using the planetary gears, but may be a structure using a worm gear, for example.

FIG. 10 is a circuit diagram for driving the electric motor 141.

In FIG. 10, the motor 141 has a rotor 163 movably provided with the windings 160, 161 and 162 having three phases.

The DC power supply 99 has the same configuration as that of the first embodiment.

An output of the DC power supply 99 is connected to an inverter circuit 165 of three phases and six stones.

Switching elements 166, 167, 168, 169, 170, 171 in the inverter circuit 165
Are composed of an IGBT and a diode connected in anti-parallel to the IGBT.

All of these diodes pass current in the reverse direction immediately after switching of the switching elements 166 to 171.

The windings 160, 161 and 162 of the electric motor 1
Are connected in a so-called star connection, and one terminal of each winding is an input terminal 175, 176, or 177.

The control circuit 179 includes the switching element 16
It is connected to each of the gate terminals 6 to 171 and controls on / off of each switching element.

Also, a Hall IC provided in the motor 141
180, 181, and 182 constitute a position detecting means, which detects whether the opposing magnetic pole is an N pole or an S pole by the rotation of the rotor 163, and thereby outputs a high and low logic signal to the control circuit 179. Output to operate the control circuit 179.

FIG. 11 is a sectional view of a motor 141 according to the third embodiment.

The electric motor 141 includes the stator 190 and the rotor 1
The stator 190 has a stator core 191 having 24 teeth (teeth) formed by stacking silicon steel plates, and enamel wires are wound around the teeth of the stator core 191 respectively. 24 coils 193 to 216 configured as described above.

FIG. 12 shows a connection diagram of the windings 160, 161 and 162 by the coils 193 to 216.

The U-phase winding 160 has eight coils 19
3, 194, 199, 200, 205, 206, 21
1, 212 in series, and a V-phase winding 161
Are the eight coils 195, 196, 201, 202, 2
07, 208, 213, 214 in series,
The W-phase winding 162 includes eight coils 197, 198, 2
03, 204, 209, 210, 215 and 216 are connected in series.

Each coil is marked with a black circle, which indicates the polarity of each coil. When a current is supplied from the terminal with the black circle, the inside of each coil is indicated. That is, this indicates that an N pole is generated on the side facing the rotor 163.

On the other hand, the structure of the rotor 163 has, as shown in FIG. 11, 20 iron cores 220 to 239 and 20 strontium ferrite permanent magnets 240 to 259 sandwiched therebetween. The polarity of the 20 permanent magnets 240 to 259 has an N pole and an S pole, respectively, but the permanent magnets adjacent to each other across the iron core have the same polarity. As shown in FIG.

Thus, the ten iron cores 220, 22
2, 224, 226, 228, 230, 232, 23
4, 236 and 238 are N poles, and the other ten iron cores 221, 223, 225, 227, 229, 231,
233, 235, 237, and 239 are S poles.

With the above configuration, the motor 141 is
It has a configuration of 24 poles.

Here, the value of the self-inductance of each of the windings 160, 161 and 162 changes periodically depending on the angle of rotation.

That is, for example, in the case of the U-phase winding 160, the magnetic flux generated by the current supplied to the U-phase winding 160 at the position of the rotor 163 shown in FIG. A magnetic path is generated between adjacent coils and passes through the permanent magnet 240, and the coils constituting the U-phase winding 160 all have the same positional relationship.

In general, the magnetic path passing through the permanent magnets 240 to 259 has a relative permeability of 1 which is almost the same as that in the case of air.
Since the magnetic resistance is large because the magnetic recording medium is placed in the state of being lowered to the extent, the inductance of the U-phase winding 160 is small.

On the other hand, when the rotor 190 rotates a little more in the counterclockwise direction, since the iron core 220 faces just between the coils 193 and 194, the magnetic resistance decreases and the U-phase The inductance of the winding 160 becomes large.

When a motor 141 having a structure in which the inductance value changes according to the rotation angle is used, if a current is supplied at a timing when the inductance value increases, a reluctance torque is generated, and the electric power is reduced. It can be converted to mechanical power.

In this embodiment, the permanent magnet 24
0 to 259 and the torque (BIL torque) hijacked by the Fleming's left hand rule generated between the windings 160, 161 and 162 is also generated, so the reluctance torque and the BIL torque are added. The device is driven by the applied torque.

FIG. 13 shows an electric motor 141 according to the third embodiment.
3 shows a characteristic diagram of the torque and speed of the driving of FIG.

The point X is the operating point when the electric washing machine is rotating the washing and spinning tub 60 for washing, and the point Y is the operating point during spinning. (Reduction ratio 1/1).

In this embodiment, the control circuit 179 controls the Hall ICs 180 and 18 especially at the point Y, that is, at the time of spin-drying.
1 and 182, and the timing is electrically advanced by 50 degrees to turn on and off the switching elements 166 to 171.
At 162, a current component (negative direct-axis component) which weakens the magnetic flux of the permanent magnets 240 to 259 is generated equivalently, and is generated in each of the windings 160 to 162 even at a high speed of 880 revolutions per minute. Reduce the magnitude of induced electromotive force,
In addition to enabling current supply from the DC power supply 99, the timing at which the current of each of the windings 160 to 162 flows can be increased during the period in which the inductance value increases. The reluctance torque can be effectively used, and an electric washing machine that is advantageous in terms of ensuring the efficiency of the device can be realized.

In this embodiment, a speed reducer 142 is provided.
At the time of washing in which only the stirring blade 61 is rotated, the speed of the electric motor 141 is reduced to 1/6, and the torque is increased six times, so that the rotation of the stirring blade 61 is performed.

In the case where the speed is reduced by 1/6 by the speed reducer 142, if the speed of the stirring blade 61 is 150 revolutions per minute, the speed of the motor 141 is as high as 900 revolutions per minute. In the present embodiment, the control circuit 179 controls the output signals of the Hall ICs 180 to 182 to electrically advance the phase by 55 degrees in the same manner as in the dehydration, and the switching elements 166 to 171 are turned on and off. By doing so, the rotation of the stirring blade 61 can be driven with high efficiency by using the reluctance torque in addition to the BIL torque, and an electric washing machine having excellent washing performance can be realized.

Therefore, power can be efficiently supplied in the washing operation in which only the stirring blade 61 and both the stirring blade 61 and the washing and dewatering tub 60 are driven, and in the dehydration operation. is there.

In this embodiment, for example, the stirring blade 61 is set at 1 / min.
With 50 rotations, it is also possible to apply a high torque of 40 Nm or more, and by repeating the rotation alternately left and right, it is possible to remove terrible dirt in a short time, and in a washing method particularly required for cleaning performance. It is possible to realize an excellent electric washing machine that can cope with the problem.

In this embodiment, the rotor 163
The structure of the iron cores 220 to 239 and the permanent magnets 240 to 25
9 and alternately arranged in a sandwich shape,
The configuration is not necessarily limited to such a configuration. For example, another configuration may be used as long as the inductance of the winding changes due to rotation, such as embedding a permanent magnet in an iron core.

[0153]

As described above, the invention according to the first aspect of the present invention particularly has a washing and dewatering tub and a driving means for driving a rotating shaft of the washing and dewatering tub. An electric motor having a winding whose inductance changes according to the rotation angle, and an inverter circuit, the inverter circuit having a configuration including a DC power supply, a switching element, and a control circuit for turning on and off the switching element, In addition to suppressing the winding current and suppressing copper loss, the current rating of the switching element, which is a component of the inverter circuit, is also suppressed. It is assumed that.

According to a second aspect of the present invention, there is provided the electric washing machine according to the first aspect, further comprising liquid supply means for supplying a washing liquid into the washing and dewatering tub during washing. The washing liquid received from the liquid supply means is re-separated from the object to be washed by centrifugal force, so that the winding current is suppressed and washing with less entanglement and damage of the object to be washed is enabled. .

According to a third aspect of the present invention, there is provided an electric washing machine according to the second aspect, wherein the liquid supply means includes a water receiving tub and a water receiving tub cover, and the washing and dewatering tub is provided in the water receiving tub. The water-receiving tub cover covers the upper part of the water-receiving tub, and is rotated between the washing and dewatering tub and the water-receiving tub by a pumping action by rotating the washing and dewatering tub. With the configuration in which the washing liquid is discharged from between the washing and dewatering tub and the water receiving tub cover toward the substantially rotation center of the washing and dewatering tub, the winding current is also suppressed, with a simple configuration, An object of the present invention is to realize an electric washing machine having high cleaning performance.

According to a fourth aspect of the present invention, in particular, the electric motor of the electric washing machine according to any one of the first to third aspects is configured to have a permanent magnet, so that the torque by the permanent magnet can be reduced. By generating both torques due to the inductance change, the winding current is also suppressed, realizing an electric washing machine that can efficiently supply power during both washing and spinning operations. is there.

According to a fifth aspect of the present invention, in particular, the electric motor of the electric washing machine according to any one of the first to fourth aspects is driven in a state of being directly connected to the shaft of the washing and dewatering tub. With this configuration, the winding current is also suppressed, and an electric washing machine with a simple configuration is realized.

According to a sixth aspect of the present invention, there is provided an electric washing machine according to any one of the first to fifth aspects.
A stirrer and a clutch are provided, the stirrer is provided inside the bottom surface of the washing and spin-drying tub, the clutch switches rotation transmission from the electric motor to the washing and spin-drying tub, and the electric motor operates when the clutch is off. When the clutch is ON, the washing and dewatering tub is driven together with the stirring blade when the clutch is ON. It is intended to provide an electric washing machine capable of performing the following.

[0159] The invention according to claim 7 is characterized in that the washing and dewatering tub, the stirring blade disposed at the bottom of the washing and dewatering tub, and the driving means for driving the rotating shaft of the washing and dewatering tub and the stirring blade are provided. Wherein the driving means comprises: a motor having a winding whose inductance changes according to a rotation angle; a clutch for switching rotation transmission from the motor to the washing and dewatering tub; and an inverter circuit. The circuit includes a DC power supply and a switching element that intermittently supplies power to the winding in synchronization with the motor, and a control circuit that turns on the switching element during an increase period of the inductance, and the driving unit includes: The clutch is turned off at the time of washing to rotate the stirring blade, and the clutch is turned on at the time of spin-drying, and the washing and spin-drying tub is rotated with the stirring blade. With a simpler structure, the ratio of the supply current of the winding at each operating point of the torque and speed during washing and dehydration is suppressed, and the copper loss of the winding and the current rating required for the switching element are suppressed. This is to realize a washing machine.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a cross section of an electric washing machine according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of the driving means.

FIG. 3 is a sectional view of the electric motor.

FIG. 4 is a wiring diagram of the motor.

FIG. 5 is a sectional view of the clutch.

FIG. 6 is a graph showing the relationship between the speed and torque of the washing and dewatering tub.

FIG. 7 is a sectional view of an electric motor according to a second embodiment.

FIG. 8 is a configuration diagram of a cross section of an electric washing machine according to a third embodiment.

FIG. 9 is a configuration diagram of a main part around the speed reducer.

FIG. 10 is a circuit diagram of the driving means.

FIG. 11 is a sectional view of the electric motor.

FIG. 12 is a wiring diagram of the same motor.

FIG. 13 is a graph showing the relationship between speed and torque.

FIG. 14 is a configuration diagram of a cross section of an electric washing machine according to a conventional technique.

FIG. 15 is a circuit diagram of the same driving means.

FIG. 16 is an operation waveform diagram of the inverter device.

FIG. 17 is a detailed configuration diagram of a bottom portion of the water receiving tank.

[Explanation of symbols]

 43 Water Receiving Tank Cover 60 Washing and Dewatering Tank 61 Stirring Blade 62 Water Receiving Tank 63, 140 Driving Means 64, 141 Motor 75 Clutch 80, 165 Inverter Circuit 80-82, 160-162 Winding 84-89, 166- 171 Switching element 96, 179 Control circuit 99 DC power supply 150 Washing shaft 240-259 Permanent magnet

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Taketoshi Sato 1006 Kazuma Kadoma, Kazuma, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. (reference) 3B155 AA01 AA03 AA06 BA09 BB05 BB15 BB19 CA06 CA07 CA16 CB06 FA14 FD08 GC06 HB10 HC05 HC07 KA33 KB10 KB11 KB27 LA02 LB18 LB26 LC02 LC14 MA01 MA02 MA07 MA09

Claims (7)

[Claims] An electric motor having a washing and dewatering tub and a driving means for driving a rotating shaft of the washing and dewatering tub, wherein the driving means has a winding whose inductance changes according to a rotation angle; A switching element for intermittently supplying power to the DC power supply and the winding in synchronization with a motor; and controlling the switching element to turn on the switching element during an increase period of the inductance. Electric washing machine with a circuit. 2. A washing machine according to claim 1, further comprising a liquid supply unit for supplying a washing liquid to the inside of the washing and dewatering tub during washing, wherein the laundry is separated from the laundry by centrifugal force of the washing liquid received from the liquid supplying unit. The electric washing machine according to claim 1. 3. The liquid supply means has a water receiving tub and a water receiving tub cover, and the washing and dewatering tub is rotatably disposed in the water receiving tub, and the water receiving tub cover is provided on the water receiving tub. The washing liquid between the washing and dewatering tub and the water receiving tub is washed with the washing liquid between the washing and dewatering tub and the water receiving tub cover by a pump action by covering the upper portion and rotating the washing and dewatering tub. 3. The electric washing machine according to claim 2, wherein the electric washing machine is configured to discharge toward a substantially rotation center of the dewatering tub. 4. The electric washing machine according to claim 1, wherein the electric motor has a permanent magnet. 5. The electric washing machine according to claim 1, wherein the electric motor is driven while being directly connected to a shaft of the washing and dewatering tub. 6. A washing machine comprising a stirring blade and a clutch, wherein the stirring blade is provided inside a bottom surface of the washing and dewatering tank, and the clutch switches rotation transmission from the electric motor to the washing and dewatering tank.
The motor according to any one of claims 1 to 5, wherein the motor drives only the stirring blade when the clutch is off, and drives the washing and dewatering tub together with the stirring blade when the clutch is on. An electric washing machine as described. 7. A washing and dewatering tub, a driving means for driving a stirring blade disposed at a bottom portion of the washing and dewatering tub, and a rotating shaft of the washing and dewatering tub and the stirring blade, wherein the driving means comprises An electric motor having a winding whose inductance changes according to the angle, a clutch for switching rotation transmission from the electric motor to the washing and dewatering tub, and an inverter circuit, wherein the inverter circuit includes a DC power supply and the winding. A switching element for intermittently supplying power in synchronization with an electric motor; and a control circuit for turning on the switching element during an increase period of the inductance. And an electric washing machine which rotates the washing and dewatering tub together with the agitating blade by rotating the clutch at the time of spin-drying.