JP4847552B2 - Washing and drying machine - Google Patents

Description

  The present invention relates to a washing and drying machine using a dehumidifying and drying method using a heat pump.

  An example of the structure of a drum-type washing / drying machine using a dehumidifying and drying system using a heat pump is shown in FIG. FIG. 4 is a cross-sectional view showing the main configuration of the drum type washing and drying machine.

  In this washing machine, the water tank 2 is supported in a suspended state in the washing machine main body 1 by a suspension structure (not shown). A drum 3 formed in a bottomed cylindrical shape is supported in the water tank 2 with its axial direction inclined downward from the front side to the back side. On the front side of the aquarium 2 is formed a clothing doorway 4 leading to the opening end of the drum 3, and by opening the door 5 that closes the opening provided in the upward inclined surface on the front side of the washing machine body 1 so as to be openable and closable, Laundry can be taken in and out of the drum 3 through the clothing entrance 4.

  The drum 3 has a large number of through holes 6 formed in the peripheral surface thereof that communicate with the water tank 2, and is provided with stirring protrusions 3a for stirring clothes at a plurality of positions on the inner peripheral surface. The drum 3 is rotationally driven in the forward and reverse directions by a drum motor 7 attached to the back side of the water tank 2. In addition, a water injection pipe 8 and a drain pipe 9 are connected to the water tank 2 to perform water injection and drainage into the water tank 2 by controlling a water injection valve and a water discharge valve (not shown).

  When the door 5 is opened, laundry and detergent are put into the drum 3, and the operation is started by an operation on the operation panel 10 provided on the front surface of the laundry dry body 1, for example, a water injection pipe is provided in the water tank 2. A predetermined amount of water is injected from 8, the drum 3 is driven to rotate by the drum motor 7, and the washing process is started. By the rotation of the drum 3, the laundry accommodated in the drum 3 is lifted in the rotation direction by the stirring protrusion 3a provided on the inner peripheral wall of the drum 3, and the stirring operation of dropping from the lifted appropriate height position is repeated. As a result, the laundry has the effect of tapping and washing.

  After the required washing time, the dirty washing liquid is discharged from the drain pipe 9 and the washing liquid contained in the laundry is dehydrated by a dehydrating operation of rotating the drum 3 at a high speed. The rinsing process is performed by pouring water from 8. Also in this rinsing process, the laundry stored in the drum 3 is rinsed by repeating the stirring operation of being lifted and dropped by the stirring protrusion 3 a by the rotation of the drum 3.

  This drum-type washing and drying machine is provided with a function of drying laundry stored in the drum 3, and the air in the water tank 2 is exhausted and dehumidified by the circulation air passage 11 to be heated and dried. Is again blown into the water tank 2. In the middle of the circulation air passage 11, a heat pump unit comprising a dehumidifying means such as an evaporator 12 and a heating means such as a condenser 13 and a circulation fan 14 serving as an air blowing means are provided. The evaporator 12 and the condenser 13 are arranged at the lowest position of the circulation air passage 11 as a heat exchange part with the circulation air.

  By rotating the circulation fan 14, an air flow is generated in the circulation air flow path 11, and the air in the drum 3 containing the laundry is introduced into the circulation fan 14 from the water tank 2 through the through holes 6. It is exhausted to the pipe line 15 and dehydrated by dehydrating the evaporator 12 positioned upstream of the circulation fan 14 and heated by heat exchange with the condenser 13, so that it is always dry hot air. The

  The dried high-temperature air is sent from the circulation fan 14 to the air duct 16 to the water tank 2 and blown into the water tank 2. The high-temperature dry air blown into the water tank 2 enters the drum 3 through the through holes 6 and escapes to the water tank 2 while being exposed to laundry such as clothes, and is again introduced into the circulating air introduction pipe line 15. The drying process is carried out by repeating the circulation of air in the circulation air passage 11.

  FIG. 5 is a block diagram showing a schematic configuration of a control device for controlling the operation of the drum type washing and drying machine having the above configuration. However, the illustration of the control unit other than the part related to the driving of the drum motor 7 is simplified.

  In this control device, the AC power of the commercial power supply 21 is smoothed by a rectifying / smoothing circuit including a rectifier 22 and a smoothing capacitor 23, and the DC power is converted into an inverter circuit 24 for a drum motor, an inverter circuit 25 for a fan motor, and a compressor This is supplied to the inverter circuit 26.

  The drum motor inverter circuit 24 converts the DC power into three-phase AC power, which is supplied as driving power for the drum motor 7. Similarly, the three-phase AC power converted by the fan motor inverter circuit 25 is supplied to the fan motor 27 for the circulation fan 14, and the three-phase AC power converted by the compressor inverter circuit is supplied to the compressor 28 of the condenser 13. Supplied.

  The control unit 29 configured by the microcomputer controls each inverter circuit 24, 25, 26 based on the driving instruction input from the input setting unit 30 and the monitoring information of the driving state detected by each detecting means, Moreover, although illustration is abbreviate | omitted, operation | movement of a water supply valve, a drain valve, etc. is controlled.

  In the drawing, only the circuit for the drum motor inverter circuit 24 is specifically shown, but the other inverter circuits 25 and 26 have the same configuration. The drum motor 7 includes a stator having three-phase windings 7a, 7b, and 7c and a rotor (not shown) having two-pole permanent magnets, and three position detection elements 31a, 31b, and 31c are provided. DC brushless motor. The position detection elements 31a to 31c output a rotor position signal for every electrical angle of 60 degrees corresponding to the rotor magnetic pole position.

  The inverter circuit 24 that controls the rotation of the drum motor 7 is configured by connecting six switching elements 24a to 24f in a three-phase bridge, and a flywheel diode is connected in parallel to each switching element 24a to 24f. Rotor position detection signals detected by the position detection elements 31 a to 31 c are input to the control unit 29. Based on the rotor position detection signal, the drive circuit 32 performs PWM control of the on / off states of the switching elements 24a to 24f. Thereby, energization to the three-phase windings 7a, 7b, 7c of the stator is controlled, and the rotor is rotated at a required rotational speed.

  The control unit 29 also includes a rotation speed detection unit 33 to which detection outputs of the three position detection elements 31a to 31c are input. The rotation speed detection unit 33 detects the period each time the position detection signal of any of the three position detection elements 31a to 31c changes, and calculates the rotation speed Nd of the rotor from the period. Using the rotational speed Nd, processing such as cloth amount detection is performed.

  In the washing / drying machine having the above-described configuration, after the drum motor 7 is driven to rotate the drum 3 at a high speed, the drum motor inverter circuit 24 is stopped, and the drum 3 may continue to rotate freely. At that time, the drum motor 7 generates an electromotive force due to the inertial rotation of the drum 3. Effective use of this electromotive force without wasting is important for achieving energy saving.

Patent Document 1 describes a technique for avoiding wasteful consumption of electromotive force generated by inertial rotation of a motor during motor control in an inverter washing machine. That is, charging / discharging means comprising a power storage means and a switching element is connected in parallel with the smoothing capacitor, and charging / discharging is controlled via the charging / discharging means. As a result, electric power generated by inertial rotation immediately after the motor is stopped is charged in the power storage means and discharged during operation, so that the motor can be started more smoothly and the generated electric power of the motor can be used without waste.
Japanese Patent Laid-Open No. 11-276781

  However, in the configuration of Patent Document 1, a power storage unit is necessary, which causes an increase in cost.

  By the way, in the washing / drying machine using the heat pump, the mode of the preliminary drying operation may be set. In the preliminary drying operation, the drum motor 7 is driven to rotate the drum 3 at a high speed to dehydrate the laundry, and at the same time, the fan motor 27 and the compressor 28 are driven to send warm air to the drum 3. This mode warms the laundry inside.

  During this pre-drying operation, it is conceivable to use the rotational energy of the drum 3 due to inertial rotation after the drum motor 7 is stopped during dehydration rotation to drive the compressor 28 and the fan motor 27 to achieve energy saving. However, it is necessary not only to simply supply the regenerative power from the drum motor 7 to the compressor 28 and the fan motor 27, but also to ensure a stable operation during the preliminary drying operation.

  Then, this invention aims at providing the washing-drying machine which can use the electromotive force by the inertial rotation of the drum at the time of the preliminary drying operation using a heat pump effectively at low cost, and can ensure the stable driving | operation. To do.

  In order to solve the above problems, a washing and drying machine according to the present invention includes a drum that accommodates laundry and performs a rotational motion, a water tank that rotatably includes the drum and is elastically supported in the washing machine body. A drum motor that rotationally drives the drum, a fan motor that rotationally drives a fan that blows air into the drum, a heat pump unit that cools and dehumidifies the air blown by the fan, and a refrigerant of the heat pump unit , A rectifying / smoothing circuit for converting AC power to DC power, a voltage detection circuit for detecting the voltage of the DC power, and the drum motor, fan motor, and compressor based on the DC power of the rectifying / smoothing circuit Drum motor inverter circuit, fan motor inverter circuit, Comprises an inverter circuit for fine compressor, a relay connected in series with the AC power supply, and a control unit for controlling the driving of each of said inverter circuit and the relay.

  The controller drives the drum motor to rotate the drum at a high speed to dehydrate the laundry, and simultaneously drives the fan motor and the compressor to send warm air to the drum. A function of controlling a pre-drying operation for warming the laundry, and during the pre-drying operation, the controller stops the drum motor inverter circuit after dehydrating for a predetermined time and simultaneously opens the relay. The power supply from the AC power source to the rectifying and smoothing circuit is cut off, and the relay is returned to the closed state when the electromotive force due to inertial rotation of the drum is lower than a predetermined magnitude.

  According to the above configuration, the electromotive force due to the inertial rotation of the drum at the time of preliminary drying operation using a heat pump is effectively used at a low cost by providing a relay, and power is supplied by an AC power source according to a decrease in electromotive force. By returning to, stable operation can be ensured.

  The washing and drying machine of the present invention can take the following aspects based on the above configuration.

  That is, when the DC voltage detected by the voltage detection circuit is lower than the switching threshold, it can be determined that the electromotive force is lower than the predetermined magnitude.

  Alternatively, the apparatus includes a rotation sensor that detects the rotation speed of the drum motor, and determines that the electromotive force is lower than the predetermined magnitude when the rotation speed detected by the rotation sensor is lower than a predetermined value. It can be.

  Further, the control unit reduces the power consumption of the fan motor and the compressor so that the DC voltage detected by the voltage detection circuit does not drop below a predetermined control reference value during a period in which the relay is open. Preferably, the electromotive force when the control becomes impossible to maintain the DC voltage reference value by controlling the power consumption of the fan motor and the compressor is set as a predetermined magnitude of the electromotive force.

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

(Embodiment)
FIG. 1 shows a block diagram of a motor driving device of a drum type washer / dryer according to an embodiment of the present invention. The overall structure of the drum-type washing and drying machine in the present embodiment is the same as that shown in FIG. The basic configuration of the motor drive device shown in FIG. 1 is the same as that of the conventional example shown in FIG. Therefore, the same reference numerals are assigned to similar elements, and the overlapping description is simplified.

  Also in the present embodiment, in the motor drive device shown in FIG. 1, the AC power of the commercial power source 21 is smoothed by the rectifier 22 and the smoothing capacitor 23, and the DC power source is the drum motor inverter circuit 24, the fan motor inverter. The circuit 25 and the compressor inverter circuit 26 are supplied. The control unit 29 has a function of controlling the preliminary drying operation, drives the drum motor 7 to rotate the drum 3 at a high speed, dehydrates the laundry, and simultaneously drives the fan motor 27 and the compressor 28 to Is sent to the drum 3 to warm the laundry in the drum 3.

  A relay 34 connected in series is provided between the commercial power supply 21 and the rectifier 22 in order to effectively use the electromotive force generated by the inertial rotation of the drum 3 during the preliminary drying operation. In order to control the relay 34, a voltage detection circuit 35 that detects the voltage of the DC power supply of the rectifying and smoothing circuit including the rectifier 22 and the smoothing capacitor 23 is used. The voltage detection circuit 35 includes resistors 35 a and 35 b connected in parallel with the smoothing capacitor 23, and a connection node between the resistors 35 a and 35 b is connected to the control unit 29. The relay 34 is closed during normal operation, and in the pre-drying operation mode, the control unit 29 controls on (closed) / off (open).

  Control for the relay 34 for effective use of regenerative power is performed after the drum motor inverter circuit 24 is stopped and the drum 3 starts inertial rotation after dehydrating for a predetermined time in the preliminary drying operation. . The operation will be described with reference to FIGS. FIG. 2 is a flowchart showing the operation during the preliminary drying operation by the motor driving device of the present embodiment.

  As shown in FIG. 2, when the preliminary drying operation is started (step S10), the control unit 29 controls the drum motor inverter circuit 24, the fan motor inverter circuit 25, and the compressor inverter circuit 26 so as to control the drum motor. 7. Drive of the fan motor 27 and the compressor 28 is started (step S20). Thereafter, it is determined whether or not a predetermined time has elapsed since the start of dehydration (step S30). After dehydration for a predetermined time, the next operation is started. That is, when the predetermined time has elapsed, the drum motor inverter circuit 24 is stopped (step S40). Thereby, the drum 3 shifts to inertial rotation.

  At the same time as the drum motor inverter circuit 24 is stopped, the relay 34 is opened (step S50), and the power supply from the commercial power supply 21 to the rectifier 22 is cut off. In this state, the drum motor 7 generates an electromotive force by the rotational energy of the drum 3 due to inertial rotation. The electric power is supplied to the fan motor inverter circuit 25 and the compressor inverter circuit 26 via the drum motor inverter circuit 24.

  Thus, while the relay 34 is in the open state, the regenerative power from the drum motor 7 is supplied to the fan motor inverter circuit 25 and the compressor inverter circuit 26 instead of the DC voltage obtained by rectifying and smoothing the commercial power supply 21. Is done. Therefore, the rotational energy of the drum 3 due to inertial rotation can be used effectively. Although not shown, while the relay 34 is in the open state, the control unit 29 consumes power of the fan motor 27 and the compressor 28 so that the DC voltage detected by the voltage detection circuit 35 does not drop below a predetermined control reference value. To control. Thereby, the preliminary drying operation can be maintained in a stable state. However, such control of power consumption is not essential for obtaining the effect of power regeneration according to the present embodiment.

  In this state, the control unit 29 determines whether or not the voltage of the DC power source of the rectifying / smoothing circuit including the rectifier 22 and the smoothing capacitor 23 is lower than a predetermined switching threshold based on the detection output of the voltage detection circuit 35. (Step S60). When the voltage of the DC power supply is lower than the switching threshold, the relay 34 is controlled to be closed (step S70). As a result, the use of the regenerative power due to the inertial rotation of the drum 3 returns to the power supply from the commercial power source 21. Then, after the predetermined time has elapsed in the preliminary drying operation (step S80), the preliminary drying operation ends (step S90).

  FIG. 3 is a waveform diagram for explaining the effect of power regeneration by the above operation. 3A shows the number of rotations of the drum 3, and FIG. 3B shows the voltage across the smoothing capacitor 23, that is, the voltage of the DC power supply of the rectifying and smoothing circuit. (C) shows the power consumption of the compressor 28 (same for the fan motor 27).

  When the preliminary drying operation starts, the drum rotation speed (a) increases, and after reaching the predetermined rotation speed, the rotation speed is maintained and the dehydration rotation is continued. At this stage, the relay (c) is turned on, the voltage (b) of the DC power supply is kept at a predetermined magnitude, and the power consumption (d) of the compressor 28 is a constant magnitude accordingly.

  When the drum motor inverter circuit 24 is stopped at time t1, the drum rotation speed (a) drops due to inertial rotation. At this time, the relay (c) is controlled to be turned off, and the voltage (b) of the DC power supply decreases due to the balance between the current supplied by the electromotive force of the drum inertia rotation and the power consumption by the fan motor 27 and the compressor 28. go. Further, the power consumption (d) of the compressor 28 is controlled to a low value so that the DC voltage does not drop below a predetermined control reference value.

  When the voltage (b) of the DC power supply falls below the switching threshold at time t2, the relay (c) is controlled to be turned on, and the voltage (b) of the DC power supply returns to a predetermined value. Further, the power consumption (d) of the compressor 28 is also controlled to a normal magnitude.

  In the above configuration, it is determined whether the voltage of the DC power supply has dropped below a predetermined switching threshold based on the detection output of the voltage detection circuit 35 because the electromotive force due to inertial rotation of the drum 3 is greater than a predetermined magnitude. This is to detect the decrease. This is because when the electromotive force is lowered, it becomes impossible or inappropriate to stably drive the fan motor 27 and the compressor 28 due to the regenerative power, so that the relay 34 is turned on to return to the power supply by the AC power source 21.

  Thus, the configuration is not limited to detecting that the electromotive force of the drum motor 7 is lower than a predetermined magnitude based on the detection output of the voltage detection circuit 35. For example, the electromotive force is based on the number of rotations of the drum motor 7. It is also possible to use a configuration for detecting that the value has decreased below a predetermined size. That is, as the rotation sensor, the rotation speed detection unit 33 that detects the rotation speed based on the outputs of the position detection elements 31a to 31c is used. When the output detected rotational speed is lower than a predetermined value, it is determined that the electromotive force is lower than a predetermined magnitude. Since the electromotive force of the drum motor 7 corresponds to the number of rotations, according to this configuration, it is possible to perform power regeneration without increasing costs.

    By the way, as described above, while the relay 34 is in the open state, the control unit 29 consumes power of the fan motor 27 and the compressor 28 so that the DC voltage detected by the voltage detection circuit 35 does not drop below a predetermined control reference value. To control. When the electromotive force is reduced to such an extent that such control becomes impossible, it is necessary to return to the power supply by the AC power supply 21 in order to ensure stable operation. Therefore, a predetermined magnitude of the electromotive force of the drum motor 7 that is a reference for turning on the relay 34 can be set as an electromotive force when the DC voltage reference value cannot be maintained by controlling the power consumption.

  According to the washing and drying machine of the present invention, it is possible to effectively use the electromotive force generated by the inertial rotation of the drum at a low cost, and to ensure a stable operation and to have a mode of a preliminary drying operation using a heat pump. Useful for laundry dryers.

The block diagram which shows the motor drive device of the drum type washing-drying machine in Embodiment 1 of this invention Flow chart showing operation during pre-drying operation by the motor drive device Waveform diagram for explaining the effect of power regeneration during preliminary drying operation by the motor drive device Sectional drawing which shows the structure of the drum type washing-drying machine using the dehumidification drying system by the heat pump of a prior art example Block diagram showing the motor drive device of the washing and drying machine

DESCRIPTION OF SYMBOLS 1 Washing machine main body 2 Water tank 3 Drum 3a Stirring protrusion 4 Clothes entrance / exit 5 Door 6 Through-hole 7 Drum motor 7a, 7b, 7c Three-phase winding 8 Water injection pipe 9 Drain pipe 10 Operation panel 11 Circulation ventilation path 12 Evaporator 13 Condenser 14 Circulating fan 15 Circulating air introduction line 16 Blowing line 21 Commercial power supply 22 Rectifier 23 Smoothing capacitor 24 Drum motor inverter circuits 24a to 24f Switching element 25 Fan motor inverter circuit 26 Compressor inverter circuit 27 Fan motor 28 Compressor 29 control unit 30 input setting unit 31a, 31b, 31c rotor position detection element 32 drive circuit 33 rotation speed detection unit 34 relay 35 voltage detection circuit

Claims (4)

A drum that houses the laundry and performs a rotational movement;
A water tub containing the drum rotatably and elastically supported in the washing machine body;
A drum motor for rotating the drum;
A fan motor that rotationally drives a fan that blows air into the drum;
A heat pump unit that heats the air blown by the fan after cooling and dehumidifying;
A compressor for transporting the refrigerant of the heat pump unit;
A rectifying / smoothing circuit for converting AC power into DC power;
A voltage detection circuit for detecting the voltage of the DC power supply;
An inverter circuit for a drum motor, an inverter circuit for a fan motor, and an inverter circuit for a compressor that supply AC power to the drum motor, the fan motor, and the compressor, respectively, based on a DC power source of the rectifying and smoothing circuit;
A relay connected in series to the AC power source;
Each inverter circuit and a control unit that performs drive control of the relay,
The controller drives the drum motor to rotate the drum at a high speed to dehydrate the laundry, and simultaneously drives the fan motor and the compressor to send warm air to the drum. Has the function of controlling the pre-drying operation to warm the laundry
In the preliminary drying operation, the control unit stops the drum motor inverter circuit after dehydrating for a predetermined time, and simultaneously shuts off the power supply from the AC power source to the rectifying and smoothing circuit by opening the relay. And the relay is returned to a closed state when an electromotive force due to inertial rotation of the drum falls below a predetermined magnitude.   The washing / drying machine according to claim 1, wherein when the DC voltage detected by the voltage detection circuit is lower than a switching threshold, the electromotive force is determined to be lower than the predetermined magnitude.   2. A rotation sensor that detects the number of rotations of the drum motor is provided, and when the number of rotations detected by the rotation sensor decreases below a predetermined value, it is determined that the electromotive force has decreased below the predetermined level. The washing dryer as described in. The control unit controls power consumption of the fan motor and the compressor so that a DC voltage detected by the voltage detection circuit does not drop below a predetermined control reference value during a period in which the relay is open. ,
The said electromotive force when it becomes impossible to maintain the said DC voltage reference value by control of the power consumption of the said fan motor and the said compressor was set as a predetermined magnitude | size of the said electromotive force. The washing dryer according to any one of the above.

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