JP3394687B2 - Inverter device and washing machine - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an inverter device for driving a motor and a washing machine.

[0002]

2. Description of the Related Art A conventional general washing machine uses a single-phase induction motor, and the single-phase induction motor rotates a pulsator or a dehydration tub at a rotation speed determined by a commercial power frequency. In this case, for example, a clutch is used to switch the rotation speed according to the commercial power frequency, and the rotation speed is variably controlled by a reduction gear and a pulley or belt provided for adjusting the rotation speed and torque. .

Control systems such as an on / off system and a phase control system have been proposed for varying the number of revolutions of a single-phase induction motor, but in both cases, noise and vibration increase.
There was a problem that the variable width was also narrow. In order to eliminate these drawbacks, an inverter control type washing machine using a three-phase motor has recently been proposed. The three-phase motor means an induction motor or a three-phase DC brushless motor.

In order to drive this three-phase motor, it is necessary to apply three-phase alternating currents which are 120 ° out of phase with each other. Therefore, as shown in FIG. 20, a power transistor or an IGBT (Insulated) is added to the inverter device.
6 switching devices such as Gate Bipolar Transistor)
3 by using an arm structure corresponding to each phase
It has a phase full-wave bridge configuration. FIG. 20 shows a case where the transistors 35a to 35f are used. Upper arm transistors 35a-35c and lower arm transistor 35
Each phase (U phase, V phase) of the motor 21 is connected to each connection point of d to 35f.
Phase, W phase) are connected.

To briefly explain FIG. 20, the commercial power supply 54 is once converted into a DC voltage by the rectifying circuit 53 and the smoothing capacitor 52. Then, this DC voltage is supplied to each arm. Transistor 3 that constitutes each arm
5a to 35f are on / off controlled by drive circuits 36a to 36f. The drive circuit 36a to 36f includes a control unit 90.
Drive signals are sent from each.

As a result, a three-phase alternating current is generated by the signal from the control unit 90. Then, this three-phase alternating current is supplied to the three-phase motor 21 to drive the three-phase motor 21. The free wheel diodes 34a to 34f are connected in parallel with the transistors 35a to 35f, respectively.

Further, the drive circuits 36d to 36 on the lower arm side
Power is supplied to f by a common power supply circuit 37d. On the other hand, in the drive circuits 36a to 36c on the upper arm side, the emitters of the transistors 35a to 35c have windings of each phase (U phase, V phase, Since they are connected to the W phase) and are in a floating state, the power supply circuits 37a to 37a are separately provided.
7c is provided.

The use of a DC brushless motor as the three-phase motor 21 has an advantage that noise and vibration can be reduced as compared with an induction motor. Generally, a DC brushless motor includes a three-phase armature winding, a rotor formed of permanent magnets, and Hall elements 40a to 40c that detect the rotational position of the rotor. Unlike the induction motor, the DC brushless motor has hall elements 40a to 40c.
The three-phase alternating current is generated based on the signal that is synchronized with the rotor position detected in (3) and is supplied to the armature winding to rotate.

In the washing machine, as shown in FIG. 21, the pulsator is operated so as to rotate forward, stop, reverse, stop ... In the washing machine using the DC brushless motor. Then, in order to completely stop the motor, for example, the upper arm transistors 35a to 35c are turned off, and the lower arm transistors 35d to 35f are turned on to apply the brake. In FIG. 21, the signal HU,
HV, HW, HW, LU, LV and LW are transistors 35a, 35b, 35c, 35d, 35e and 35, respectively.
The drive signal output from the control unit 90 for controlling f is shown.

[0010]

In the above-mentioned conventional washing machine (FIG. 20), three transistors each having a different reference level are required to drive the upper arm transistors 35a to 35c.
Since individual independent drive power supply circuits 37a to 37c are required, four power supply circuits 37a to 37d are required in the inverter section which constitutes the arm. Further, in order to make the signal level of the drive signal output from the control unit 90 such as a microcomputer compatible with the inverter unit, an insulating circuit 55 such as the photocouplers 55a to 55f is usually required in the interface unit between the inverter unit and the control unit 90. It was.

Further, since the power supply circuit 37e for the controller 90 is also required, the conventional washing machine described above requires at least five independent power supply circuits. Further, since the insulating circuit 55 is indispensable to the interface portion, the circuit becomes complicated, the circuit board becomes large, and the number of parts increases, so that the reliability is deteriorated. Further, this has also been a factor of increasing the cost of the circuit.

When the DC brushless motor 21 is used as the three-phase motor, it is indispensable to detect the rotor position by using the hall elements 40a to 40c. It will cause a startup failure.

In the above conventional washing machine, the pulsator repeats forward rotation, stoppage, reverse rotation, stoppage, etc. during washing and rinsing, so when the forward rotation is stopped, the electric brake is applied as shown in FIG. The motor position is stopped completely so that the rotor does not fluctuate so that the rotor position can be detected well. However, in reality, when connecting the motor to the pulsator or dehydration tank via the pulley, belt or reduction gear, this deviation of the rotor position detection occurs due to the deflection of the belt and the play of the reduction gear. And a step-out phenomenon had occurred.

The present invention solves the above-mentioned problems. In an inverter-controlled washing machine, the number of independent power supply circuits is reduced to reduce the size of the circuit, and in the case of controlling a DC brushless motor, the rotor is well suited. An object of the present invention is to provide a washing machine that can detect a position and perform a quick reversal operation.

[0015]

In order to achieve the above object, the constitution of the present invention will be described below. Here, the first to tenth configurations are inverter devices, but it is assumed that the inverter devices are installed in the washing machine in the eleventh configuration. In the first configuration of the present invention, a switching element connected to each of an upper arm and a lower arm of an inverter device that supplies a drive current to each phase of a three-phase motor, a drive circuit that drives each of the switching elements, and A power supply circuit that applies power to each drive circuit of the lower arm, and each drive circuit of the upper arm includes a bootstrap type power supply circuit that charges a capacitor from the power supply circuit via a diode. And above
In the washing machine to perform the reverse and forward rotation of the motor alternately, upper
The motor is driven by a transmission device whose rotation is playable.
It is said to be transmitted to the rotating body of the washing machine.
The electric brake can be applied to the
The barter device has a rotation mode for rotating the motor and
Equipped with a stop mode with an electric braking period
In the stop mode, apply an electric brake to the motor.
Before and after the opening period, all the switching elements
There is a period for turning off the
In off control before work, deceleration due to mechanical friction of the motor
To the brake operation with the off control after the brake operation.
After alleviating the play of the transmission that occurs more
It is designed to perform an inversion operation.

With such a configuration, the inverter device drives the motor by supplying the drive current. When the motor is rotated intermittently, such as when washing or rinsing a washing machine, the inverter device has a stop mode in which the electric brake is applied during the rotation mode. The switching element of is turned off for a certain period. Next, for example, all the switching elements of the upper arm are turned off and all the lower arms are turned on to apply an electric brake to stop the motor. And
All the switching elements are turned off again and then the rotation mode is entered. The play includes not only mechanical allowance such as backlash of gears but also bending of a belt or the like under tension.

Further, in the second structure of the present invention, the above first
In the above configuration, the electric braking is performed by turning off all the switching elements of the upper arm and turning on all the switching elements of the lower arm.

With such a configuration, the inverter device applies the electric brake by turning off all the switching elements of the upper arm and turning on the switching elements of the lower arm in the stop mode. That is, since the switching elements are provided with the freewheel diodes so as to be in parallel with each other, the regenerative current is attenuated on the lower arm side so that the braking is applied.

According to the third aspect of the present invention, the first
In the above configuration, the electric braking is performed by turning on all switching elements of the upper arm and turning off all switching elements of the lower arm.

According to this structure, in the inverter device, in the stop mode, the upper arm is turned on and the lower arm is turned off, so that the regenerative current is supplied to the upper arm side and the brake is applied.

Further, in the fourth structure of the present invention, the first structure
In the configuration, a brake arm including a resistor and a switching element is connected to both ends of the upper arm and the lower arm, and the electric brake turns off all the switching elements of the upper arm and the lower arm,
This is performed by turning on the switching element of the brake arm.

With such a configuration, the inverter device loops the regenerative current by turning on the switching element of the brake arm in the stop mode, and attenuates the current by the resistance provided in the brake arm to generate an electric current. Apply the brakes.

According to the fifth aspect of the present invention, the first
In any one of the fourth to fourth configurations, a unit for detecting the rotor position of the motor is provided, and in the stop mode, the rotor position is detected after the electric brake is applied for a certain time, and the rotor position is detected for a certain time. If they do not match before and after, the electric brake is applied for a certain period of time until the rotor positions match.

According to this structure, when the inverter device shifts from the rotation mode to the stop mode, first, all the switching elements of the upper arm and the lower arm are turned off.
Next, the electric brake is applied by turning off the upper arm and turning on the lower arm for a certain time, for example, to turn off all the switching elements, and then detect the rotor position. After that, the brake is applied again for a certain period of time, all the switching elements are turned off, and then the rotor position is detected. If the rotor position has not changed before and after this braking, the rotor is completely stopped, and the stop mode is changed to the rotation mode, for example, the rotation direction is reversed to rotate the motor.

In the sixth aspect of the present invention, the first
In any one of the fourth to fourth configurations, a unit for detecting the rotation speed of the motor is provided, and a period in which all the switching elements are turned off is provided immediately after shifting from the rotation mode to the stop mode. The time for applying the electric brake is determined based on the rotation speed of the motor.

With such a configuration, the inverter device detects the rotation speed of the motor at the end of the off period of all the switching elements provided at the start of the stop mode, and when the rotation speed is high, the braking time is lengthened, Conversely, when the rotation speed is slow, the braking time is shortened. As a result, the braking time is determined according to the rotation speed until it completely stops.

In the seventh structure of the present invention, the sixth structure
In the configuration, immediately after shifting from the rotation mode to the stop mode, a period for turning off all the switching elements is provided, and the rotation speed of each of the motors is detected before and after the start of this period, and these rotation speeds are detected. The acceleration is calculated from the above, and the time for applying the electric brake is determined based on the acceleration.

According to such a configuration, the inverter device detects the rotation speed of the motor at the start and end of the period when all switching elements that are initially provided are turned off when shifting to the stop mode, and from these rotation speeds. Calculate the acceleration. If the acceleration is large, the large braking is applied by the resistance of the transmission mechanism or the like without applying the braking. Therefore, the braking time is shortened to shorten the braking time. On the other hand, when the acceleration is small, the braking time is lengthened to stop the motor completely.

In the eighth structure of the present invention, the first
In any one of the fourth to fourth configurations, when the rotation mode is changed to the stop mode, the electric current of the motor is detected, and the time for applying the electric brake is determined based on the electric current.

According to such a configuration, the inverter device detects the current flowing through the motor when shifting to the stop mode, and determines the braking time based on the current value. For example, when the current value is large, the rotation speed is high, so that the braking time is lengthened. On the contrary, when the current value is small, the rotation speed is small, so the braking time is shortened.

Further, in a ninth structure of the present invention, the above first
In any one of the fourth to fourth configurations, the time for applying the electric brake is determined based on the regenerative current of the motor in the stop mode.

According to such a configuration, the inverter device detects the regenerative current in the stop mode, and if the regenerative current is large, the inverter is rotating rapidly, so that the braking time is lengthened, and conversely, if the regenerative current is small, the braking time is shortened. Shorten.

According to a tenth structure of the present invention, in any one of the first to ninth structures, the transmission device transmits the rotation of the motor via a belt.

In such a structure, the transmission device is provided with a pulley on the rotary shaft of the motor, for example, and a belt is hung on the pulley to transmit the rotation of the motor. By this, the tension applied to the belt is removed and then the rotation mode is set, so that the inverter device can successfully detect the rotor position even if the transmission mechanism using the belt is provided.

According to the eleventh structure of the present invention, in a washing machine equipped with an inverter device for driving a three-phase motor, the washing machine is connected to an upper arm and a lower arm for supplying a driving current to each phase of the three-phase motor. A switching circuit for driving the switching element, a driving circuit for driving the switching element, a power circuit for applying power to the driving circuits of the lower arm, and a driving circuit for the upper arm via diodes from the power circuit. And a circuit for power supply of a bootstrap method for charging a capacitor by using a power supply.

According to such a construction, the washing machine controls the switching element provided on the arm by turning on / off the switching element.
Generates a phase alternating current and drives a three phase motor. Of the drive circuits that drive these switching elements, the one on the lower arm side has a common ground side, so that power is supplied to the drive circuit by one power supply circuit. On the other hand, the bootstrap type circuit is provided on the upper arm side, and the capacitors are charged through the respective diodes, and power is supplied to each drive circuit by these capacitors.

According to a twelfth configuration of the present invention, in the eleventh configuration, a control circuit for outputting a drive signal to each of the drive circuits is provided, and the power supply circuit supplies power to the control circuit. .

In such a structure, the power supply circuit for the control circuit and the drive circuit may be a single power supply circuit.

According to a thirteenth configuration of the present invention, in the eleventh configuration, a control circuit for outputting a drive signal to each of the drive circuits is provided, and the drive circuit is a high breakdown voltage IC, and the high breakdown voltage IC is provided. Is provided with a level shift circuit for level shifting the drive signal to the reference potential of each drive circuit of the upper arm.

In such a structure, a high withstand voltage IC in which a drive drive circuit is integrated is used in the washing machine, and the drive signal from the control circuit is used as the reference level of the drive circuit of the upper arm on the upper arm side. In order to adapt, the signal level is changed by using a level shift circuit such as a high voltage transistor, and the signal level is input to the drive circuit.

According to a fourteenth structure of the present invention, in any one of the eleventh to thirteenth structures, the inverter device is any one of the first to tenth structures.

According to such a construction, when the washing machine performs the braking operation, for example, all the upper arms are turned off and all the lower arms are turned on. Therefore, at this time, the capacitors of the bootstrap circuit are charged, respectively. Power can be supplied to the drive circuit.

[0043]

DETAILED DESCRIPTION OF THE INVENTION

<First Embodiment> A first embodiment of a washing machine to which the present invention is applied will be described below with reference to the drawings. Figure 1
FIG. 1 shows a schematic configuration of the inside of the washing machine of this embodiment. The washing machine 1 is a one-tank type fully automatic washing machine, and includes a dehydrating tub 12 and a water tub 13 which are also used as a washing tub inside a main body 11. The water tank 13 is made up of the suspension 11 and the main body 11
The dehydration tank 12 is rotatably mounted inside the water tank 13 so as to be rotatable. A pulsator 15 is provided at the bottom of the dehydration tank 12. The main body 11 has a lid 11a for loading and unloading laundry.

The washing machine 1 includes a water supply pipe 16 for supplying water to the water tank 13, a water supply valve 17 for controlling water supply, and a water tank 13.
A water distribution pipe 18 for draining the water from the tank, a drain valve 19 for controlling the drainage, and a circulation pump 20 for circulating the water in the water tank 13 are provided. Normally, the water supply pipe 16 is connected to the water supply, but it is also possible to connect the water supply pipe 16 to a bath pump (not shown) to inject bath water into the aquarium 13.
Further, by operating the circulation pump 20, air can be mixed into the water in the water tank 13 to accelerate the dissolution of the detergent and enhance the washing effect.

A motor 21 and a transmission mechanism 22 having a rotating shaft 22a are fixed to the lower portion of the water tank 13. The rotation of the motor 21 is transmitted to the transmission mechanism 22 via a belt 23 hung between a pulley 21b provided on the rotary shaft 21a and a pulley 22b provided on the rotary shaft 22a. The transmission mechanism 22 contains a reduction gear and a clutch, reduces the rotation of the motor 21 and transmits it to the dehydration tank 12 and the pulsator 15.

In the washing process and the rinsing process, the pulsator 15 to which the rotation of the motor 21 is transmitted rotates to generate a rotating water flow in the water tank 13. In the dehydration step, the dehydration tub 12 to which the rotation of the motor 21 is transmitted rotates at the same speed as the pulsator 15, and the centrifugal force generated thereby removes water from the laundry in the dehydration tub 12. The dehydration tank 12 is provided with a large number of small holes for discharging the separated water. However, the dehydration tank 12 may be a tank without holes.

The dewatering tank 12 and the pulsator 15 rotate in synchronization with the rotation of the motor 21 when they are connected to the rotating shaft 22a by the clutch, and stop when the motor 21 is stopped. Further, the load applied to the spinning dewatering tank 12 and the pulsator 15 becomes the load of the motor 21.

On the upper part of the main body 11, there are provided an operating section 24, a display section 25, a buzzer 26, and a lid sensor 27 for detecting the opening / closing of the lid 11a, and the water level in the aquarium 13 is provided on the side of the aquarium 13. A water level sensor 28 for detecting A main control unit (control means) 31 including a microcomputer for controlling the entire operation of the washing machine 1 is provided below the operation unit 24, and the motor 21 is provided with a rotational driving force in the vicinity of the motor 21. There is provided a drive unit 32 for supplying the electric power, and a control unit (control means) 33 composed of a microcomputer for controlling the rotation of the motor 21 via the drive unit 32. The washing machine may be configured without the circulation pump 20 and the like.

FIG. 2 shows an outline of a configuration relating to operation control of the washing machine 1. The main control unit 31 stores a program describing the operation contents of each process such as washing, rinsing, dehydration, etc., and the execution sequence of the process, that is, a processing course, and according to this program, the water supply valve 17 and the drain valve 19 are controlled. Opening / closing, operation of circulation pump 20, and motor 21 in transmission mechanism 22
Of the transmission destination of the rotation of the sub-control unit 3
The rotation of the motor 21 is controlled via 3.

The main controller 31 determines the state of the lid 11a based on the output of the lid sensor 27, and does not start the dehydration process of rotating the dehydration tank 12 at a high speed when the lid 11a is open. When the lid 11a is opened during the dehydration process, the motor 21 is stopped and the rotation of the dehydration tank 12 is immediately stopped.

In the treatment course, in addition to the fully automatic course in which the steps of washing, intermediate dehydration, rinsing, and dehydration are performed in this order, the treatment can be stopped until the middle of the steps, or the treatment can be started from the middle of the steps. There are several courses available. The user can wash the desired course by operating the operation unit 24. It is also possible to give an instruction to perform only one arbitrary step.

In the fully automatic course, the cloth amount is detected before the washing process. This is a process for calculating an appropriate value of the water level and the number of rotations of the motor 21, and the main control unit 31 is in a state where the laundry is put in the washing tub 12 and before the water is supplied to the tub 13, the pulsator is supplied. 15 is rotated for a short time, and the amount of cloth is judged from the load applied to the motor 21 at this time. Main control unit 31
In the subsequent washing process and rinsing process, the water supply amount is controlled while monitoring the output of the water level sensor 28 according to the detected cloth amount. When the motor 21 is rotated, the target rotation speed is set based on the detected cloth amount.

By operating the operation unit 24, the user can also specify a desired water level and the strength and time of washing, rinsing and dehydrating. The designation by these manual operations is useful when washing a course other than the fully automatic course. When the strength of washing or the like is designated, the main control unit 31 sets the target rotation speed of the motor 21 based on the designation.

The display unit 25 is for displaying information for assisting the user's operation, the process in progress, the remaining time until the completion of all processes, and the like. When the lid 11a is opened at the start of the dehydration process, or when any abnormality occurs, the main control unit 31 displays a message to that effect on the display unit 25 and also issues an alarm sound from the buzzer 26.

In the washing machine 1 of this embodiment, a three-phase four-pole DC brushless motor is used as the motor 21, and drive power is supplied to the motor 21 from the inverter circuit 41 in which six switching elements have a three-phase full-wave bridge configuration. I am trying to supply it. The drive unit 32 includes the inverter circuit 41,
The drive circuit 45 is configured to drive the switching element of the inverter circuit 41 based on the drive signal (inverter signal IS) provided from the sub control unit 33 .

As shown in FIG. 2, the main control unit 31 transmits the control signal S2 for controlling the rotation of the motor 21 to the sub control unit 33 together with the clock CL indicating the timing thereof. The clock CL is not particularly limited, but is 250 Hz in this embodiment. The reason why the clock CL is set to 250 Hz is that the inverter signal IS has a high frequency of about 3 to 5 kHz and the commercial power source is 50 Hz or 60 Hz. Because.

The sub control unit 33 reads the signal S1 in synchronization with the clock CL. Further, the sub control unit 33 transmits the signal S1 in synchronization with the clock CL. In the washing machine 1 where there are many restrictions on wiring due to waterproofing, serial communication is more efficient than parallel communication because the number of signal lines is smaller.

In the main controller 31, the inverter signal IS and the clock CL are made asynchronous by using a delay means such as a timer. As a result, noise induced on the lines of the clock CL and the signals S1 and S2 by the inverter signal IS is not taken in by the sub control unit 33, so that there is an effect such as malfunction prevention. Further, when the lid is opened during dehydration, the main control unit 31 stops the supply of the clock CL, and when the sub control unit 33 detects this, the output of the inverter signal IS is immediately stopped and the motor 21 is emergency stopped. To do. This prevents the danger that the user will put his / her hand into the dehydration tub that is rotating at high speed.

Next, the configuration of the inverter device incorporated in the washing machine will be described in detail with reference to FIG. The commercial power supply 54 is converted into pulsating DC by the rectifying unit 53. A diode bridge is used for the rectification unit 53, for example. The DC voltage rectified by the rectifying unit 53 is the smoothing capacitor 52.
Is smoothed by. Then, this DC voltage is supplied to the drive unit 32, and is converted into a three-phase AC by the drive unit 32. The DC brushless motor 21 is rotated by supplying the drive current of the three-phase AC to the DC brushless motor 21.

The drive unit 32 includes an inverter circuit 41 (see FIG.
(See), three pairs of arms corresponding to three phases are formed,
Six transistors 35a, 3 as switching elements
5b, 35c, 35d, 35e and 35f are provided. 30. As described above, in the smoothing capacitor 52 (+) 3 which is connected to the side of the transistor 35a~35c referred to as upper arm, (-) three transistors 35d~35f connected to side of the lower arm .

Then, the six transistors 35a to 35
Free wheel diodes 34a are connected in parallel to f.
~ 34f are connected. The connection point between the upper arm and the lower arm is at each phase (U of the armature winding of the DC brushless motor 21).
Phase, V phase, W phase). A drive circuit 36 is provided at the base of each of the transistors 35a to 35f.
a to 36f are connected to drive the transistors 35a to 35f under the control of the sub control unit 33.

The DC brushless motor 21 is provided with Hall elements 40a to 40c for detecting the rotor position. The rotor position detection circuit 43 obtains the rotor position based on the signals from the Hall elements 40a to 40c, and the rotor position information is transmitted to the sub control unit 33. A power supply circuit 37b that supplies power to the sub control unit 33 is provided. The power supply to the drive circuits 36d to 36f on the lower arm side is supplied by the power supply circuit 37a. The power supply circuit 37
A voltage reduced by a transformer or the like is supplied from the commercial power supply 54 to a and 37b.

With respect to the upper arm, the bootstrap circuit connects the power supply circuit 37a to the diodes 50a.
The capacitors 51a to 51c are charged via 50c. The voltages across the capacitors 51a to 51c are applied as power supply voltages to the drive circuits 36a to 36c, respectively. As a result, one power supply circuit 37
a serves as a power source for the six drive circuits 36a to 36f.

Next, the bootstrap circuit will be described. FIG. 4 is a circuit diagram for explaining the operation of the bootstrap circuit, and for simplification, only one phase (U phase) is shown. The diode 50a has the anode side connected to the (+) side of the power supply circuit 37a via the resistor R, and the cathode side connected to the capacitor 51a.

The voltage across the capacitor 51a is applied as the power supply voltage for the drive circuit 36a, and its (-) side is connected to the midpoint of the transistors 35a and 35d. The resistor R is inserted to limit the charging current of the capacitor 51a. The end point 56 represents that it is connected to another bootstrap circuit.

To charge the capacitor 51a, the transistor 35d is turned on while the transistor 35a is turned off. Then, as shown by an arrow G, the capacitor 5 is passed from the power supply circuit 37a through the diode 50a.
A current flows through 1a, and the capacitor 51a is charged. After that, when the transistor 35d is turned off, the drive circuit 36a operates in the upper arm by the charged electric charge of the capacitor 51a, and the transistor 35a can be turned on.

For continuous operation, the condenser 51a
It is necessary to turn on the transistor 35d to charge the transistor 35d at an appropriate timing according to the amount of charge discharge. Although the power supply circuits 37a and 37b are separately provided in FIG. 3 , they may be commonly provided as one power supply circuit as long as the power supply capacity can be secured.

The circuit of the ordinary washing machine uses elements such as a triac for operating loads such as the drain valve 19, the water supply valve 17 and the bath water pump, and the ground of the sub control unit 33 and the inverter circuit side. Since there is no problem in sharing the ground with the above, there is no problem in sharing the power source.

The photocoupler 55, which is required in the conventional washing machine (FIG. 20), is not required in the present embodiment. However, as shown in FIG. 5, the drive unit is an HVIC.
This is because the voltage is adjusted internally by the (high breakdown voltage IC) 60. Input terminal 67 of HVIC60
The drive signal from the sub-control unit 33 is input to. The drive signal is stored in the input buffer 61 so as to cope with the dead time.

The HVIC 60 includes drive circuits 36a to 36f.
Is built in. The power supply for the upper arm is provided by a bootstrap circuit which is provided outside the HVIC 60 and includes diodes 50a to 50c and capacitors 51a to 51c. In the upper arm, the reference voltage changes, but the signal from the input buffer 61 is adapted to the reference level of the drive circuit 36a by the level shift circuit 62 composed of a high breakdown voltage transistor. In the drive circuit 36a, the U-phase voltage is monitored by the undervoltage protection circuit 79 and adjustment is performed by the upper arm logic 77 at 36a. Further, the drive circuits 36b and 36c for the V phase and the W phase have the same configuration.

The HVIC 60 causes the transistors 35a ...
35f is controlled to generate a three-phase alternating current, and drives the motor 21 (see FIG. 3) connected to the terminal 68. The terminals 75 and 76 are terminals to which the DC voltage generated by the rectifier circuit 53 (see FIG. 3) and the smoothing capacitor 52 (see FIG. 3) is input. The HVIC 60 is provided with an overcurrent protection circuit 63 and an undervoltage protection circuit 65, and outputs a warning signal from the circuit 64 when the rated range is exceeded. Although the power supply circuit 37a and the inverter circuit 41 have the same power supply ground, there is no problem as described above.

In this embodiment, in the washing and rinsing process, the pulsator 15 (see FIG. 1) is intermittently repeatedly rotated in the forward and reverse directions, while the DC brushless motor 21 is electrically braked to stop the motor 21 once. The mode is inserted. Immediately after shifting from the normal rotation mode to the stop mode, all the transistors 35a to 35f are turned off as shown in FIG. 6, and this switching pattern is continued for a certain period K1. In the period K1, the motor 21 gradually decelerates due to loss due to mechanical friction of the reduction gear, the pulley, etc., and the rotation speed decreases. The period K1 is about 0.1 to 0.8 milliseconds although it depends on the gear case and the like.

Next, the upper arm transistors 35a.about.
35c are all turned off, and the lower arm transistor 35d
Turn on all ~ 35f. In FIG. 6, the drive signals (HU, HV, HW) output from the sub control unit 33 are at a low level, and the drive signals (LU, LV, LW) are at a high level, which indicates that. As a result, the electric brake is applied and the motor 21 is completely stopped, as will be described later. The period K2 is not particularly limited, but is 0.3 to 0.
It is about 5 milliseconds.

Since the motor 21 is forcibly stopped by the electric brake, excessive tension is generated on the belt 23 that transmits the rotation to the gear case 22 of the motor 21, and bending is generated. If the mode is changed to the reverse rotation mode as it is, the rotor of the motor 21 slightly moves due to the bending due to the tension at the moment when the brake is released, and the rotor position shifts. Therefore, when the motor 21 is started, a start failure or a step-out phenomenon occurs.

Therefore, in the present embodiment, as shown in FIG. 6, after the braking period K2, the transistors 36a to 3a.
A period K3 is provided in which all 6f are turned off again. As a result, the motor 21 becomes free, so that the tension applied to the belt 23 is relieved and the rotor position is prevented from shifting.

After that, if the rotor position is detected at the end of the period K3, the rotor position will not be displaced, so that the engine can be started successfully. Even when the rotation mode for reverse rotation shifts to the stop mode, and the rotation mode for normal rotation changes,
Periods K1 to K3 are provided to continue the same switching pattern.

FIG. 8 shows how the electric brake is applied by the regenerative current. Transistor 35a in rotation mode
When the state is turned on to the stop mode, the upper arm transistors 35a to 35c are turned off and the lower arm transistors 35d to 35f are turned on in the braking period K2 (see FIG. 6). This allows the motor 2
The current flowing into the U phase of No. 1 flows out from the V phase and the W phase, passes through the transistors 35e and 35f, respectively, and loops through the freewheel diode 34d. Since the current loops and is attenuated in this way, the motor 21 is braked.

Next, the processing of the sub control unit 33 which carries out the above operation will be described. FIG. 7 is a flowchart of the processing. First, in step S1, it is determined whether or not the washing or rinsing step is completed. When the washing or rinsing process is completed by a timer or the like, this process ends.

Next, in step S2, the direction of rotation of the motor 21 is determined by the forward rotation flag and the reverse rotation flag. In the case of normal rotation, the process proceeds to step S3, and processing is performed in a predetermined normal rotation sequence. On the other hand, in the case of reversing, the process proceeds to step S13, and processing is performed in a predetermined reverse rotation sequence. In the forward rotation sequence (S3) and the reverse rotation sequence (S13), the U-phase, the V-phase, and the W-phase synchronize with each other by 12 in synchronization with the rotor position detection signal.
The drive signals (HU, HV, HW, LU, LV, LW) are output so that signals with a 0 ° phase shift are generated. The rotation direction of the motor 21 can be changed by the drive current flowing in each phase (U phase, V phase, W phase).

In the case of normal rotation, the normal rotation sequence of step S3 is continued until the normal rotation mode ends in step S4. When the normal rotation mode ends, the mode shifts to the stop mode. First, in step S5, all the upper and lower arms are turned off, and in step S6, the period K1
The switching pattern is continued until is completed.
When the period K1 ends in step S6, the upper arm is turned off and the lower arm is turned on (ON) in step S7. Then, in step S8, this switching pattern is set to the period K.
2 Continue.

After the end of the period K2, all of the upper arm and the lower arm are turned off again in step S9, and this switching pattern is continued in period S3 in step S10. After the end of the period K3, the rotor position is detected in step S11. Then, in step S12, the forward rotation flag is set to 0 and the reverse rotation flag is set to 1. Then, the process returns to step S1.

When the forward rotation flag is 0 and the reverse rotation flag is 1, it is determined in step S2 that the rotation mode is the reverse rotation mode, and the process proceeds to step S13. In step S11 at the end of the above stop mode, the rotor position is detected after the tension of the belt 23 (see FIG. 1) is removed, so that the reverse sequence of step S13 is performed without causing a start failure or the like. be able to.

The reverse rotation sequence (S13) is performed in step S
It continues until the reverse rotation mode is completed by 14. After the reverse rotation mode ends, shift to the stop mode,
In step S15, all the upper and lower arms are turned off. Then, this switching pattern is set in step S1.
At K6, the period K1 continues. Next, in step S17, the upper arm is turned off and the lower arm is turned on. Then, this switching pattern is continued for the period K2 in step S18.

Next, in step S19, all the upper and lower arms are turned off, and this switching pattern is continued in period K3 in step S20. Then, step S21
The rotor position is detected in step S22, and the forward rotation flag is set to 1 and the reverse rotation flag is set to 0 in step S22. And step S1
The process returns to. When the forward rotation flag is 1 and the reverse rotation flag is 0, it is determined in step S2 that the rotation mode is the forward rotation mode.

As described above, according to this embodiment,
As shown in FIG. 1, a bootstrap circuit is used to drive the upper arm and lower arm drive circuits 36a through one power supply 37a.
Since the power is supplied to 36f, the number of power circuits decreases,
The cost can be reduced. Moreover, since the number of parts is reduced, reliability against failures and the like is improved. In addition, the capacitors 51a to 51c are simultaneously operated during the braking operation.
Since the charging is performed on the upper arm, the drive circuits 36a to 36c on the upper arm side can be reliably operated in the rotation mode.

A switching element such as an IGBT can be used in the transistors 35a to 35f.
Further, in the washing machine of the present embodiment (FIG. 1), the rotation is transmitted by the belt 23, but even if a transmission mechanism having a backlash such as gears is used, there is an effect of alleviating play in the backlash. The position detection accuracy can be improved. The brake can be applied by turning on a part of the lower arm at the time of braking, but the maximum effect is obtained when all the lower arms are turned on.

<Second Embodiment> A second embodiment of the present invention will be described. Since it is almost the same as the first embodiment, the description of the overlapping parts will be omitted. In the first embodiment, the lower arm applies regenerative braking, but in the present embodiment, part of the processing is changed and the upper arm applies regenerative braking.

FIG. 9 shows a flowchart of the processing in the sub control unit 33 (see FIGS. 1 and 2). The upper arm is turned on and the lower arm is turned off in steps S25 and S26 in the period K2. Only the process is different from the process (FIG. 7) of the first embodiment, and the other processes are the same, so the same reference numerals are given and description thereof is omitted.

During the braking period K2, a regenerative current flows through the upper arm as shown in FIG. FIG. 10 shows an example of a case where the transistor 35a is turned on in the rotation mode and is then shifted to the stop mode. After shifting to the stop mode, the upper arm transistor 35a
~ 35c is turned on, the lower arm transistors 35d ~ 3
5f turns off. As a result, the current flowing into the U phase of the motor 21 flows out from the V phase and the W phase, passes through the freewheel diodes 34b and 34c, and loops through the transistor 35a. The brake is applied in this way.

After the braking operation, the upper arm may be turned off and the lower arm may be turned on to charge the capacitors 51a to 51c (see FIG. 3) constituting the bootstrap circuit. At this time, charging ends immediately, so there is no significant time loss.

<Third Embodiment> A third embodiment of the present invention will be described. In FIG. 11, a braking arm composed of a resistor 70 and a transistor 71 which is a switching element is connected to both (+) and (−) sides of a DC voltage supplied to the transistors 35a to 35f of the upper and lower arms. It is a partial circuit diagram of an inverter device. The other parts are almost the same as those in the first embodiment, and there are some changes in the processing. This processing will be described.

FIG. 12 is a flow chart of the processing of this embodiment, which is almost the same as the processing shown in FIG.
The only difference is that the switching patterns of 1 to K3 (see FIG. 6) are changed. Since other processes are the same, the same reference numerals are given and the description thereof will be omitted.

When shifting from the normal rotation mode to the stop mode, the upper arm, the lower arm and the brake arm are turned off in step K30 in the period K1. next,
The braking operation in the period K2 is performed by turning off the upper arm and the lower arm and turning on the braking arm as in step S31. Then, in the period K3, step S
As in 32, the upper arm, the lower arm, and the brake arm are turned off to put the motor in a free state.

Even when the reverse rotation mode is switched to the stop mode, the same switching pattern as in step S30 is set in step S33 during the period K1. Period K2
Then, in step S34, the same switching pattern as in step S31 is set. In period K3, step S35
Then, the same switching pattern as in step S32 is set.

After the braking operation, the upper arm may be turned off and the lower arm may be turned on to add a switching pattern for charging the capacitors 51a to 51c forming the bootstrap circuit.

<Fourth Embodiment> A fourth embodiment of the present invention will be described. In the washing machine of this embodiment, in order to stop the motor 21 (see FIG. 3) completely, the brake is applied a plurality of times to check whether or not the motor 21 is completely stopped. Since the other parts are the same as those in the first embodiment, duplicate description will be omitted.

As shown in FIG. 13, when the normal rotation mode is shifted to the stop mode, the motor 21 is first brought into the free-run state in the period T1. This period T1 is about 0.1 to 0.5 milliseconds as described above, and is uniquely determined in the washing process. In the next period T2, all upper arms are turned off and all lower arms are turned on. The period T2 is about 0.3 to 0.5 milliseconds as described above. Subsequent period T
3 Turn off the upper arm and the lower arm again and turn the motor 21
To release the belt tension. This prevents the rotor position from moving, but the rotor position may shift due to external factors such as residual tension and vibration.

Therefore, in this embodiment, the rotor position is detected at the end time t1 of the period T3 and is temporarily stored in the memory built in the sub control unit 33 (see FIG. 3). Then, the brake is applied again for the period T2a, and the motor 21 is brought into the free state during the period T3a. The rotor position is detected at the end time t2 of the period T3a and compared with the rotor position at the time t1 stored in the memory.

If the rotor positions match, it is determined that the rotor is not moving, the stop mode is terminated, and the reverse rotation mode is entered. If they are different, the sub-control unit 33 replaces the rotor position detected at time t2 with the previous position information, and updates and stores it. Then, the braking period T again
2b and the free period T3b of the motor 21 are provided, rotor detection is performed at the end time t3 of the period T3b, and the rotor position information stored previously is compared.

If they match, the mode is changed to the rotation mode. If different, the rotor position information stored in the memory is updated, and a braking period and a free period are further provided. In this way, this operation is repeated until the rotor positions match. If the braking period T2 is sufficient for braking, the braking periods T2a, T2b, etc. can be made sufficiently shorter than the initial braking period T2.

FIG. 14 shows a flowchart of the processing for performing the above operation. In this figure, only the processing portion when the rotation mode in the normal rotation sequence is changed to the stop mode is shown.

The normal rotation sequence in step S40 is continued until it is determined in step S41 that the end time is reached. When the normal rotation sequence (S40) is completed, the upper arm and the lower arm are all turned off in step S42, and the switching pattern is continued in period T1 in step S43. Next, in step S44, the upper arm is turned off, the lower arm is turned on, and the brake is applied. The period in which the brake is applied in step S45 is set to T2.

Next, in step S46, all the upper and lower arms are turned off, and this switching pattern is set in step S46.
At 47, the period T3 continues. Next, in step S48, the rotor position is detected and stored in the memory built in the sub control unit 33. Then, in step S49, the upper arm is turned off and the lower arm is turned on to apply the brake,
At 50, the period T2a continues. Then, in step S51, all the upper and lower arms are turned off, and this switching pattern is continued in period T3a in step S52.

Then, in step S53, the rotor position is detected, and in step S54, it is compared with the previously detected rotor position stored in the memory. If they match, the forward rotation flag is set to 0 and the reverse rotation flag is set to 1 in step S55, and steps S1 and S2 in FIG.
Make a decision. On the other hand, if the rotor positions do not match in step S54, the rotor position (memory contents) detected in step S56 is updated, and the process returns to step S49.
A braking period T2a (T2b in FIG. 13) and a free period T3a (T3b in FIG. 13) are provided. After that, the process is repeated until the rotor is completely stopped.

Even when the reverse rotation sequence (not shown) shifts to the stop mode, steps S42 to S54,
The process of S56 is performed as it is, and the normal rotation flag is set to 1 and the reverse rotation flag is set to 0 at the end of the stop mode. In the present embodiment, the braking is applied by the same method as the first embodiment, but the same effect can be obtained by applying the braking by the method of the second or third embodiment.

As described above, in the present embodiment, the rotor is completely stopped in the stop mode and then the rotor is shifted to the next rotation mode. Therefore, detection deviation of the rotor position or the like does not occur and start-up failure occurs. And step out phenomenon are prevented.

<Fifth Embodiment> A fifth embodiment of the present invention will be described. In the present embodiment, the braking time is optimized by controlling the braking amount according to the rotation speed of the motor 21. The other parts are the same as those in the first embodiment, and thus the duplicate description will be omitted.

As shown in FIG. 15, when the normal rotation mode is changed to the stop mode, a free period K1 is first provided in which all the upper and lower arms are turned off. The period K1 is, for example, about 0.1 to 0.5 milliseconds and is uniquely determined in the washing process. Then, at the end time t1 of the period K1, the rotation speed of the motor 21 (see FIG. 3) is detected by the rotor position detection circuit 43, a rotation speed detection circuit (not shown), or the like. The next braking period K2 is determined based on this rotation speed. When the rotation speed of the motor 21 is high, FIG.
15B, the period K2 is set large, and conversely, when the rotation speed is slow, the period K2 is shortened to shorten the period as shown in FIG. 15B.

Then, the upper arm and the lower arm are turned off to provide a free period K3 to relieve the tension applied to the belt 23 (see FIG. 1). Then, the next reverse rotation mode is entered. Specifically, the characteristics of the rotation speed and the time until it is stopped by the brake are experimentally obtained, and a period K2 during which the motor 21 can be stopped is provided according to the rotation speed.

FIG. 16 shows a flowchart of the processing for performing the above operation. In this figure, only the processing portion when the rotation mode in the normal rotation sequence is changed to the stop mode is shown.

The normal rotation sequence in step S60 is continued until it is determined in step S61 that the end time is reached. When the normal rotation sequence (S60) is completed, the upper arm and the lower arm are all turned off in step S62, and the switching pattern is continued in period K1 in step S63. Next, in step S64, the rotation speed of the motor 21 is detected. Based on this detection result, the time of the braking period K2 is determined in step S65 as described above. Then, in step S66, the upper arm is turned off, the lower arm is turned on, and the brake is applied. In step S67, the braking period is set to K2.

Next, in step S68, all the upper and lower arms are turned off, and this switching pattern is set in step S68.
At 69, the period K3 continues. Then, in step S70, the rotor position is detected. The last step S7 of the stop mode
At 1, the forward rotation flag is set to 0 and the reverse rotation flag is set to 1. The subsequent processing and the case of shifting to the stop mode from the reverse sequence are as described in the above embodiment.

As described above, according to this embodiment,
Since the braking period K2 is provided so that the rotor can be completely stopped regardless of whether the rotation speed is fast or slow, extra braking is not applied. If the accuracy of rotation speed detection is high, the braking period K2 may not be determined at the end time t1 of the period K1, the rotation speed may be detected at any time, and the braking period may be continued until the rotation speed becomes zero. . Regarding the braking system, the second
Alternatively, the method described in the third embodiment may be used.

<Sixth Embodiment> A sixth embodiment of the present invention will be described. The difference between this embodiment and the fifth embodiment is that the regenerative current of the motor 21 is detected instead of detecting the rotation speed of the motor 21 in order to determine the length of the braking period K2 (see FIG. 15). To do. Since the other points are the same as those in the fifth embodiment, description thereof will be omitted. Since the regenerative current has a property of increasing as the rotation speed of the motor increases, the sub-control unit 33 (see FIG. 3) determines the braking period K2 based on the magnitude of the regenerating current. As in this embodiment, it is possible to determine an appropriate braking period K2 by detecting the regenerative current.

<Seventh Embodiment> A seventh embodiment of the present invention will be described. In the present embodiment, the fifth or sixth aspect described above is used.
Although the length of the braking period K2 is determined during the stop mode as in the first embodiment, the braking period K2 is detected by detecting the current of the motor 21 (see FIG. 3) immediately before the rotation mode is switched to the stop mode. Has been decided.

FIG. 17 shows a flowchart of the processing for performing the above operation. In this figure, only the processing portion when the rotation mode in the normal rotation sequence is changed to the stop mode is shown.

The normal rotation sequence of step S75 is continued until it is determined in step S76 that it is completed. When the forward rotation sequence (S75) is completed, the motor current is detected in step S77 before the motor is brought into the free state. Then, in step S78, the time of the braking period K2 is determined. Then, in step S79, the upper arm and the lower arm are all turned off, and the switching pattern is continued in period K1 in step S80. Next, in step S81, the upper arm is turned off, the lower arm is turned on, and the brake is applied.
In step S82, the braking period is set to K2.

Next, in step S83, all the upper and lower arms are turned off, and this switching pattern is set in step S83.
At 84, the period K3 continues. Then, in step S85, the rotor position is detected. Step S8 at the end of the stop mode
At 6, the forward rotation flag is set to 0 and the reverse rotation flag is set to 1. The subsequent processing and the case of shifting to the stop mode from the reverse sequence are the same as the processing described in the above embodiment, and the description of the other parts will be omitted.

<Eighth Embodiment> An eighth embodiment of the present invention will be described. In the present embodiment, the speed of the motor is detected before and after the free period K1 of the motor provided at the beginning of the transition to the stop mode, and the braking period K2 is determined from the state in which the rotation speed decreases.

FIG. 18 shows a flowchart of the processing of this embodiment. In this figure, only the processing portion when the rotation mode in the normal rotation sequence is changed to the stop mode is shown.

The normal rotation sequence of step S91 is continued until it is determined in step S92 that the end time is reached. When the forward rotation sequence (S91) is completed, the upper arm and the lower arm are turned off in step S92. At this time, in step S94, the rotation speed (N1) of the motor is detected by the rotor position detection circuit 43, a rotation speed detection circuit (not shown), or the like. Then, set the switching pattern in step S
At 95, the period K1 continues. Next, in step S96, the rotation speed (N2) of the motor 21 is detected.

Then, in step S97, the acceleration α is calculated. α = (N1-N2) / t0. However, t0
Is a time interval when the motor rotation speed is detected twice as shown in FIG. In step S98, the length of the braking period K2 is determined based on the acceleration α. If the acceleration α is large, the braking effect is strong even when the motor is in a free state, so that the motor can be completely stopped even if the braking period K2 is shortened. On the contrary, if the acceleration α is small, the braking period K2 is made large.

Then, in step S99, the upper arm is turned off, the lower arm is turned on, and the brake is applied. Step S
A braking period K2 is set at 100. Although the subsequent processing is not shown, the free period K3 is provided as in the above embodiment. The same processing is performed on the reverse rotation sequence side. The other parts are the same as those in the above-described embodiment, and thus the duplicate description will be omitted.

As described above, according to this embodiment,
The braking period K2 is determined by calculating the acceleration α in the free period K1. That is, the inertia of the rotor is required. Therefore, even if the degree to which the electric brake is applied may change due to external conditions or the like, the brake can be appropriately applied in response to the change.

[0125]

<Effects of claim 1> One power supply circuit is provided for the drive circuit on the lower arm side,
Since the power supply circuit supplies power to the drive circuit on the upper arm side by the bootstrap circuit, only one power supply circuit supplies power to the drive circuit. Therefore, the number of parts is reduced and the reliability of the device is improved.
There is also an effect of cost reduction. Also, brake operation
There is a period before and after switching off the switching element,
The electric brake is released during this period. At this time
The tension applied to the belt of the reaching device is removed.
This prevents the occurrence of startup failure. Especially DC
Rotorless motor detects rotor position well
Therefore, the occurrence of the step-out phenomenon is prevented. <Effect of claim 2> Since the power supply voltage can be supplied to the control circuit and the six drive circuits by one power supply circuit, the number of power supply circuits in the inverter type washing machine is reduced, and the reliability is further improved. There is an effect of improvement of and cost reduction. <Effect of claim 3> Since the level shift is performed in the high voltage IC, parts such as a photocoupler are not required.

<Effect of Claim 4> A period during which the switching element is turned off is provided before and after the braking operation, and the electric brake is released during this period.
At this time, the tension applied to the belt of the transmission device is removed. This prevents the start-up failure. In particular, even if the motor is a DC brushless motor , the rotor position can be detected well, so that the occurrence of step-out phenomenon is prevented. <Effect of claim 5 > By turning off all of the upper arms and turning on all of the lower arms, a higher braking effect can be obtained than in the case of turning on some of the switching elements.

<Effect of Claim 6 > Conversely, the maximum braking effect can be obtained by turning off all the lower arms and turning on the upper arms.

<Effect of Claim 7 > By turning off the upper arm and the lower arm and turning on the switching element provided in the brake arm, regenerative current flows in the brake arm and is provided in the brake arm. The current is attenuated by the existing resistance, and the brake is applied.

<Effect of Claim 8 > In the state where the brake is applied, tension is applied to the belt or the like, and even if the motor is started as it is,
Although the rotor position may shift at the time of start-up, resulting in poor start-up, after the brake is applied, the brake is released to remove the tension and the like so that the rotor stops completely before shifting to the rotation mode. Therefore, the startup failure and the step-out phenomenon do not occur.

<Effect of Claim 9 > For example, since an appropriate braking time is set based on the rotation speed at the time of shifting to the stop mode, the braking time can be optimized.

<Effect of claim 10 > By calculating the acceleration in the free period of the motor provided at the time of shifting to the stop mode, determining the braking time until complete stop based on the acceleration, and performing braking, The time is optimized.

<Effect of Claim 11 > The current flowing through the motor is detected at the time of shifting to the stop mode, and the braking time is determined based on the current value. Is provided, the braking time can be optimized.

<Effect of Claim 12 > Since the rotation speed can be obtained also by the regenerative current of the motor, an appropriate braking time can be determined and the braking period can be shortened.

<Effect of Claim 13 > Even when the rotation of the motor is transmitted through the belt, the tension applied to the belt during braking is removed, and the rotor position can be detected well. Is prevented.

[0135]

[0136]

[0137]

[0138]

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an entire washing machine according to a first embodiment of the present invention.

FIG. 2 is a block diagram thereof.

FIG. 3 is a circuit diagram of the inverter device.

FIG. 4 is a diagram showing a flow of a charging current of the capacitor 51a.

FIG. 5 is a block diagram when the drive circuit has an HVIC configuration.

FIG. 6 is a waveform diagram for explaining the operation.

FIG. 7 is a flowchart of the processing.

FIG. 8 is a diagram showing a flow of a regenerative current during the braking period.

FIG. 9 is a flowchart of processing of the washing machine according to the second embodiment of the present invention.

FIG. 10 is a diagram showing the flow of regenerative current during the braking period.

FIG. 11 is a diagram showing a flow of regenerative current during a braking period of the washing machine according to the third embodiment of the present invention.

FIG. 12 is a diagram showing the flow of regenerative current during the braking period.

FIG. 13 is a waveform chart for explaining the operation in the fourth embodiment of the present invention.

FIG. 14 is a flowchart of the processing.

FIG. 15 is a waveform chart for explaining the operation in the fifth embodiment of the present invention.

FIG. 16 is a flowchart of the processing.

FIG. 17 is a waveform chart for explaining the operation in the seventh embodiment of the present invention.

FIG. 18 is a waveform chart for explaining the operation in the eighth embodiment of the present invention.

FIG. 19 is a waveform diagram for explaining the operation.

FIG. 20 is a circuit diagram of a conventional inverter device.

FIG. 21 is a waveform diagram for explaining the operation.

[Explanation of symbols]

1 washing machine 11a lid 12 dehydration tank 15 pulsator 21 motor 24 Operation part 25 Display 27 Lid sensor 31 Main control unit 32 Drive 33 Sub control unit 41 Inverter circuit 43 Rotor position detection circuit

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-3-15290 (JP, A) JP-A-4-58779 (JP, A) JP-A-8-103087 (JP, A) JP-A-9- 47054 (JP, A) JP 9-163791 (JP, A) JP 51-41813 (JP, A) JP 62-296787 (JP, A) Actual development JP 59-179495 (JP, U) 62-159199 (JP, U) Tokuhei HEI-50-501920 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02P 6/24 D06F 37/40

Claims (13)

(57) [Claims] 1. A drive current is supplied to each phase of a three-phase motor.
Switching devices respectively connected to the upper arm and the lower arm of the inverter device, drive circuits for respectively driving the switching devices, power supply circuits for applying power to the respective drive circuits of the lower arm, and respective drives of the upper arm Rutotomoni the circuit and a circuit for the power supply of the bootstrap method to charge the capacitor through the respective diode from the power supply circuit, reverse and normal rotation of the motor
In the washing machine to perform alternately, the motor, through the rotation of a play transfer device
Is transmitted to the rotating body of the washing machine.
However, it is possible to apply the electric brake and
The inverter device has a rotation mode to rotate the motor and
A stop mode with a period for applying the electric brake is provided.
In the stop mode, apply an electric brake to the motor.
Before and after the opening period, all the switching elements
There is a period for turning off the
In off control before work, deceleration due to mechanical friction of the motor
To the brake operation with the off control after the brake operation.
After alleviating the play of the transmission that occurs more
Washing characterized by performing a reversing operation
Rinsing machine. 2. The washing machine according to claim 1, wherein each of the drive circuits includes a control circuit that outputs a drive signal, and the power supply circuit supplies power to the control circuit. 3. A control circuit for outputting a drive signal to each of the drive circuits, wherein the drive circuit is a high breakdown voltage IC, and the drive signal is applied to a reference potential of each drive circuit of the upper arm in the high breakdown voltage IC. The washing machine according to claim 1, further comprising a level shift circuit for level shifting each. 4. The motor is a brushless DC motor.
The transmission device is connected to the rotating shaft on the motor side and the rotating shaft on the rotated body side.
The belts hung on a pair of pulleys provided on the rolling shafts respectively.
1 to claim 1, which includes a filter.
The washing machine according to any one of 3 above. 5. The washing according to claim 1 , wherein the electric braking is performed by turning off all switching elements of the upper arm and turning on all switching elements of the lower arm. Machine. 6. The washing machine according to claim 1 , wherein the electric braking is performed by turning on all switching elements of the upper arm and turning off all switching elements of the lower arm. Machine. 7. A braking arm including a resistance and a switching element is connected to both ends of the upper arm and the lower arm, and the electric brake turns off all the switching elements of the upper arm and the lower arm, and washing machine according to claim 1 characterized by being performed by turning on the switching elements of the arm brake. 8. A means for detecting the rotor position of the motor is provided, and in the stop mode, the rotor position is detected after the electric brake is applied for a certain time, and the rotor position must match before and after the certain time. if further washing machine according to any one of claims 1 to 7, characterized in that subjecting said electrical brake fixed time until the rotor position coincides. 9. A means for detecting the rotation speed of the motor, wherein a period for turning off all the switching elements is provided immediately after shifting from the rotation mode to the stop mode, and the rotation of the motor after the lapse of this period. washing machine according to any of claims 1 to 7, characterized in that determining the time taken for the electric brake on the basis of speed. 10. Immediately after shifting from the rotation mode to the stop mode, a period in which all the switching elements are turned off is provided, and the rotation speeds of the motors are detected before and after the start of this period, respectively. The washing machine according to claim 9, wherein the acceleration is calculated from the speed, and the time to apply the electric brake is determined based on the acceleration. From 11. The rotation mode when shifting of the stop mode, detects the current of the motor, according to claim 1 or claims, characterized in that determining the time taken for the electric brake based on the current Item 8. The washing machine according to any one of Item 7. 12. The washing machine according to claim 1, wherein a time for applying the electric brake is determined based on a regenerative current of the motor in the stop mode. 13. The washing machine according to claim 1, wherein the transmission device transmits the rotation of the motor via a belt.