JP2001224889A - Drum type washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drum type washing machine generating less noise and vibration when the unbalance of washed clothes is detected. SOLUTION: A control device operates a washing motor at a constant speed of 40 rpm and 70 rpm, and after that, the speed is increased to 100 rpm to detect the unbalance of the laundry inside the washing machine. Therefore, as the laundry tumbled and gradually dispersed on the periphery inside a drum 14, generation of heavy vibration or noise is prevented when the unbalance of the laundry is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum type washing machine for stirring laundry in a drum based on rotating the drum about a horizontal axis.

[0002]

The above-mentioned drum type washing machine detects the capacity of the laundry before detecting the imbalance of the drum, and accelerates the drum from an acceleration region corresponding to the detected capacity to the unbalance detection speed. There is a configuration in which laundry is dispersed by a centrifugal force on the outer peripheral portion of the drum based on this.
In this configuration, when the laundry capacity is detected to be larger than the actual capacity, the acceleration area of the drum is set higher than the actual laundry capacity. For this reason, when the unbalance is detected, the laundry becomes a lump in the drum, and there is a possibility that large vibrations and noises may occur.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drum-type washing machine that can prevent laundry from clumping in a drum when an imbalance is detected.

[0004]

According to a first aspect of the present invention, there is provided a drum type washing machine, comprising: a water receiving tub into which water for washing is poured; a drum accommodated in the water receiving tub; A washing motor for rotating the drum about a horizontal axis; and control means for controlling the drive of the washing motor, wherein the control means detects the unbalance of the laundry before the drum is unbalanced. It is characterized by rotating at a plurality of different speeds. In the drum type washing machine according to the present invention, the drum may be driven at a set speed of less than 50 rpm and 50 rpm before the control means detects the imbalance of the laundry.
It is characterized in that it is rotated at a set speed of not less than pm. According to the first and second aspects, the drum is accelerated to the unbalance detection speed after rotating at a plurality of different speeds lower than the unbalance detection speed. As a result, the laundry gradually disperses to the outer peripheral portion of the drum while being tumbled in the drum, thereby preventing the occurrence of large vibration and noise when detecting imbalance.

According to a third aspect of the present invention, there is provided a drum type washing machine, wherein the control means detects the weight of the laundry before detecting the imbalance of the laundry, and adds the detected weight of the laundry after detecting the imbalance of the laundry. The feature is that the spin-drying operation is performed with a corresponding starting torque. According to the third aspect of the present invention, an appropriate starting torque can be set according to the detected weight of the laundry, so that the laundry is not activated when the spin-drying operation is started due to an imbalance between the weight of the laundry and the starting torque. Agglomeration in the drum and vibration and noise are prevented from occurring.

According to a fourth aspect of the present invention, when the unbalance of the laundry is larger than the unbalance determination value, the control means slows down the drum from the unbalance detection speed, and determines whether the laundry is loosened at the time of deceleration. When the value is larger than the value, the drum is accelerated to the unbalance detection speed, and the unbalance of the laundry is detected again. According to the fourth aspect, when the imbalance of the laundry is large, the laundry is tumbled based on the deceleration of the drum and the imbalance is corrected, so that large vibration and noise are surely generated. Is prevented.

In the drum-type washing machine according to the fifth aspect, the control means detects the weight of the laundry before detecting the imbalance of the laundry, and detects the weight when the imbalance of the laundry is larger than the unbalance determination value. Is characterized in that the drum is decelerated from the unbalance detection speed in a form corresponding to the above. According to the means of claim 5, an appropriate deceleration pattern can be set according to the weight of the laundry, so that the laundry is unnecessarily entangled based on sudden deceleration of a small amount of laundry, This prevents the laundry from being loosened sufficiently due to slow deceleration of the laundry.

According to a sixth aspect of the present invention, in the drum type washing machine, after the control means detects the imbalance of the laundry, the washing motor is accelerated from the unbalance detection speed to the vicinity of the vertical resonance speed of the water receiving tub. The feature is that the imbalance is detected again based on the rotation state of the washing motor. According to the means of the sixth aspect, the vibration of the drum is large near the resonance speed in the vertical direction of the water receiving tank, and the load on the washing motor is high. For this reason, the imbalance of the laundry is easily reflected on the rotation state of the washing motor, and the detection accuracy of the imbalance is improved.

According to a seventh aspect of the present invention, in the drum type washing machine, a balancer having a liquid sealed in the hollow body is provided on the drum, and the control means moves the drum near the vertical resonance speed of the water receiving tank from before and after the same. The feature is that it accelerates at a small rate. According to the means of claim 7, since the liquid is less likely to be biased in the balancer when the drum is accelerated near the resonance speed, the vibration near the resonance speed of the drum may increase due to the imbalance of the liquid. Is prevented.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. First, in FIG. 5, the cabinet 1 is formed based on combining steel plates in a rectangular box shape, and a circular opening 2 is formed in a front plate of the cabinet 1. A circular door 3 is rotatably mounted on the front plate of the cabinet 1.
The door is opened and closed based on a rotation operation of the door 3.

A cylinder 4 of a plurality of dampers 4 corresponding to a buffer mechanism is fixed to a bottom plate of the cabinet 1. Each of these dampers 4 has a structure in which a spring and a fluid (both not shown) are sealed in a cylinder 5 and a rod 6 is elastically supported by a spring. A water receiving tank 7 is fixed to the rods 6 of the plurality of dampers 4. ing. The water receiving tank 7 has a cylindrical shape with a closed rear surface, and the axial center line 8 is arranged horizontally horizontally.

A cylindrical drain port 9 is fixed to the bottom of the water receiving tank 7, and the drain port 9 communicates with the outside of the cabinet 1 through a drain hose 10. A drain valve 11 is attached to the drain port 9. The drain valve 11 is driven by a valve motor (not shown), and the drain port 9 is opened and closed based on switching of the drain valve 11 between an open state and a closed state according to the forward / reverse rotation of the valve motor. Is done.

A washing motor 12 is mounted on the rear surface of the water receiving tank 7. The washing motor 12 is an outer rotor type three-phase DC brushless motor. The stator of the washing motor 12 has 12 teeth wound with a U-phase stator coil and a V-phase stator coil wound thereon. The washing motor 12 has 12 teeth and 12 teeth wound with a W-phase stator coil (both not shown). The rotor of the washing motor 12 has 12 rotor magnets of N poles and 12 rotors of S poles. Rotor magnets (both not shown).

The rotating shaft 13 of the washing motor 12 has a water receiving tank 7
And the drum 14 is fixed, and when the washing motor 12 is driven, the drum 14 rotates integrally with the rotating shaft 13 (direct drive system). The drum 14 has a cylindrical shape with a closed rear surface, and is arranged coaxially with the water receiving tank 7 in a lateral direction. A balance ring 15 is fixed to a front end of the drum 14. The balance ring 15 has a structure in which a liquid is sealed in a hollow body, and has a function of improving the rotational balance of the drum 14.

A circular opening 16 and an opening 17 are formed in the front plate of the water receiving tank 7 and the front plate of the drum 14, and the opening 16 of the water receiving tank 7 and the opening 2 of the cabinet 1 are formed.
A cylindrical bellows 18 is interposed between the bellows. The bellows 18 connect the opening 2 and the opening 16 in a water-tight manner. In the drum 14, with the door 3 open, the bellows 18 extend from the opening 2 of the cabinet 1 to the opening 16 of the water receiving tank 7 and the drum 16. The laundry (not shown) is thrown in through the opening 17 of 14.

A plurality of projecting baffles 19 are provided on the inner peripheral surface of the drum 14. When the drum 14 rotates at a low speed, the laundry is lifted up by the baffle 19 and falls down ( Tumbling), drum 14
When rotating at a high speed, the laundry sticks to the inner peripheral surface of the drum 14 by centrifugal force. Further, a plurality of dehydration holes 20 are formed in the peripheral plate of the drum 14 over the entire area.
The inside of 4 communicates with the inside of the water receiving tank 7 through a plurality of dehydration holes 20.

An electromagnetic water supply valve 21 is provided in the cabinet 1.
Has been fixed. The water supply valve 21 has an input port and an output port (neither is shown),
The input port of the water supply valve 21 is connected to a tap (not shown) through a tap water hose. The output port of the water supply valve 21 is a tap water injection hose (not shown).
When the output port is open, tap water is injected into the water receiving tank 7 through a tap water hose and a tap water injecting hose when the output port is opened.

A water supply pump 22 is fixed in the cabinet 1. This water supply pump 22 has a pump motor 23
It is of a self-priming type driven by a driving source (see FIG. 4), and the water inlet of the water supply pump 22 communicates with a bathtub (both not shown) via a bathwater hose. Further, the water outlet of the water supply pump 22 communicates with the inside of the water receiving tank 7 via a bath water injection hose (not shown). When the pump motor 23 is driven, the bath water flows through the bath water hose and the bath water injection hose. 7 is injected.

A water level sensor 24 is provided in the cabinet 1. The water level sensor 24 is provided with a conductive pole slidably inserted in the inner peripheral portion of a cylindrical coil slidably in the axial direction, and the pole is slid according to the water level in the water receiving tank 7. It changes the amount of wrap (inductance) in the axial direction, and outputs a water level signal having a frequency corresponding to the amount of wrap between the pole and the coil (corresponding to the water level in the water receiving tank 7).

An operation panel 25 is fixed to the cabinet 1, and a circuit box 2 is mounted on a rear surface of the operation panel 25.
6 is mounted. A circuit board (not shown) is housed in the circuit box 26, and a control device 27 and a drive circuit 28 (both shown in FIG. 5) mainly composed of a microcomputer are mounted on the circuit board. I have.

The control device 27 corresponds to a control means, and a water level sensor 24 and a rotation sensor 29 are electrically connected to input terminals of the control device 27 as shown in FIG. A drive circuit 28 is provided at the output terminal.
The drain valve 11, the water supply valve 21, and the pump motor 23 are electrically connected via the.

The rotation sensor 29 comprises a Hall IC corresponding to the U-phase stator coil of the washing motor 12 and a Hall IC corresponding to the V-phase stator coil. Based on the detection of the rotor magnet by the Hall IC and the V-phase Hall IC, a U-phase position signal and a V-phase position signal are output, and the control device 27 calculates the U-phase position signal and the V-phase position signal. A W-phase position signal is generated based on the processing.

The drive circuit 28 has an inverter circuit section (not shown). This inverter circuit is formed by bridging six IGBTs, and the U-phase stator coil to the W-phase stator coil of the washing motor 12 are electrically connected to the inverter circuit.

The control device 27 has a PWM signal generation circuit, an energization signal generation circuit, and a waveform synthesis circuit (all not shown). The PWM signal generation circuit includes a speed detection unit that generates a speed detection signal based on the U-phase position signal to the W-phase position signal, and a voltage command generation that generates a voltage command based on the speed command signal and the speed detection signal. And generates a PWM signal based on comparing the voltage command with the triangular carrier signal.

The energization signal generation circuit generates six energization signals based on the U-phase position signal to the W-phase position signal. These six energization signals are for individually determining the energization phase switching timing for the six IGTs of the inverter circuit section, and the waveform synthesizing circuit synthesizes the waveforms of the six energization signals and the PWM signal. Drive signals are individually generated for the six IGBTs based on Then, each IGBT is individually turned on / off based on the drive signal, and the washing motor 12 is rotated at a speed corresponding to the speed command signal based on the application of the three-phase alternating-current voltage to the washing motor 12.

As shown in FIG. 4, a start switch 30 and a plurality of setting switches 31 are electrically connected to input terminals of the control device 27. The start switch 30 and the plurality of setting switches 31 are connected to the operation panel 2.
5 is mounted on the front surface of the control switch 27. The control device 27 controls the setting switch 3 based on an output signal from the setting switch 31.
The operation content is detected, and the washing time, the number of times of rinsing, the dehydration time, the washing course are set, and the presence or absence of the bath water use mode is determined based on the detection result of the operation content.

Next, the operation of the above configuration will be described.
In the following description, the rotation direction of the washing motor 12 during the spin-drying operation is referred to as forward rotation. When detecting the operation of the start switch 30, the control device 27 starts the automatic washing operation and executes the following washing step and rinsing step.

<Regarding the Washing Process> When the control device 27 shifts to the washing process, the drain valve 11 is closed. When the bath water use mode is not set, the water supply valve 21
Is opened, and tap water is injected into the water receiving tank 7 until the water level signal from the water level sensor 24 reaches the set water level. When the bath water use mode is set, the drive power is applied to the pump motor 23 and the water level sensor 24
The bath water is injected into the water receiving tank 7 until the water level signal from the water reaches the set water level.

When the water at the set water level is injected into the water receiving tank 7, the control device 27 tumbles the laundry in the drum 14 based on the forward and reverse rotation of the washing motor 12 at a low speed (slap washing). Then, an electrical braking force such as a DC braking force is applied to the washing motor 12 based on the elapse of the set washing time, and the washing process is completed based on stopping the washing motor 12.

<Regarding the Rinsing Step> After the washing step is completed, the controller 27 shifts to the rinsing step, and discharges the water in the water receiving tank 7 to the outside based on the opening of the drain valve 11. After the tap water or bath water is injected into the water receiving tank 7 with the drain valve 11 closed, the laundry in the drum 14 is tumbled based on the normal rotation of the washing motor 12 at a low speed. Then, an electric braking force is applied to the washing motor 12 based on the elapse of the set rinsing time, and the washing motor 12 is stopped.

When the control unit 27 stops the washing motor 12, the control unit 27 discharges the water in the water receiving tank 7 to the outside based on the opening of the drain valve 11. Then, the rinsing step is completed, and the process proceeds to the following dehydration step.

<About the dehydration step (when the first unbalance amount and the second unbalance amount of the laundry are small)
When the control device 27 shifts to the dehydration process, the starting torque Tr1 is set to “large” in step S1 of FIG. And
The process proceeds to step S2, in which a driving signal for reverse rotation is generated at a duty ratio according to the starting torque Tr1, and the washing motor 12 is driven by the starting torque Tr1 for a set time (for example, 5 seconds) based on output to the inverter circuit unit. Reverse. FIG. 3A shows a change in the rotation speed of the washing motor 12 during the spin-drying process. As is clear from FIG. 5, in step S2, the washing motor 12 is rotated at a low speed of 40 rpm, so that the laundry is not entangled during rinsing.

The controller 27 detects the rotation speed 0.5 seconds after the start of the start of the washing motor 12 in step S2 of FIG. 1, and based on the magnitude of the rotation speed, the capacity W (including water) of the laundry. Weight). Then, based on the application of an electric braking force to the washing motor 12, the washing motor 12
Is stopped, and the routine goes to Step S3. The capacity W of the laundry is set to be smaller as the rotation speed after 0.5 seconds is higher.

At step S3, the controller 27 compares the detected capacity W at step S2 with the first judgment value W1 and the second judgment value W2 (W1 <W2). And
When "detected capacity W <first determination value W1" is detected, it is determined that the capacity of the laundry is small, and the process proceeds to step S4 to set the starting torque Tr2 of the washing motor 12 during the spin-drying operation to "small". . Further, when detecting "first determination value W1≤detected capacity W≤second determination value W2", it is determined that the laundry capacity is medium, and the process proceeds to step S5.
The starting torque Tr2 is set to “medium”. When "detected capacity W> second determination value W2" is detected, the capacity of the laundry is determined to be large, and the routine proceeds to step S6, where the starting torque Tr2 is set to "large".

After setting the starting torque Tr2, the control device 27 proceeds to step S7, generates a drive signal for normal rotation at a duty ratio corresponding to the starting torque Tr1 in step S1, and outputs the signal to the inverter circuit unit. As shown in (a), the washing motor 12 is stopped after rotating forward at a low speed of 40 rpm for a set time (for example, 3 seconds).

When the control device 27 stops the washing motor 12, the process proceeds to step S8 in FIG.
N + 1 ". Then, the process proceeds to step S9,
It is determined whether the counter value N in step S8 has reached the set value No. Here, when “counter value N <set value No” is detected, the process proceeds to step S10.

When the control device 27 proceeds to step S10, it generates a drive signal for normal rotation at a duty ratio corresponding to the starting torque Tr2 set in any of steps S4 to S6. Then, a drive signal for normal rotation is output to the inverter circuit unit, and the washing motor 12 is started with the starting torque Tr2.

When the control device 27 starts the washing motor 12, the process proceeds to step S11. Here, a drive signal for forward rotation is generated, and the washing motor 12 is rotated forward at a low speed of 40 rpm for a set time (for example, 2 seconds). Thereafter, the washing motor 12 is accelerated and normally rotated at a low speed of 70 rpm for a set time (for example, 3 seconds). S11 in FIG.
a and S11b show how the washing motor 12 rotates at speeds of 40 rpm and 70 rpm.

The control device 27 controls the washing motor 12 at 70 rpm
When the motor rotates forward at a low speed of m for 3 seconds, the duty ratio is adjusted so that the acceleration rate of the washing motor 12 becomes a set value (for example, 5 rpm / second), as shown in S11c of FIG. While rotating, the rotation speed is increased from 70 rpm to a first unbalance detection speed (for example, 100 rpm). The first unbalance detection speed is experimentally set so that a rated amount of laundry is stuck in the drum 14.
When accelerating the washing motor 12 to the first unbalance detection speed, the control device 27 fixes the duty ratio and proceeds to step S12 in FIG.

When the control device 27 proceeds to step S12, it performs the operation of detecting the time Tn required for the washing motor 12 to advance by the electrical angle "360 ° / 4" 12 times. The electrical angle “360 °” of the washing motor 12 is equal to the mechanical angle “30”.
°), and the control device 27
Fixed timing of 60 ° (for example, electrical angle of 180 °
The rotation time Tn is measured at の 間 270 °). Therefore,
Twelve rotation times T1 to T12 are detected during one rotation of the washing motor 12 mechanically.

When detecting the rotation times T1 to T12, the control device 27 calculates the average rotation time T (ave) based on the calculation of the following equation (1). Next, a first unbalance amount S1 is obtained based on the calculation of the following equation (2).

(Equation 1)

The controller 27 controls the first unbalance amount S1
Is detected, the process proceeds to step S13 in FIG. 1, and the first unbalance amount S1 is compared with the set value S1o corresponding to the unbalance determination value. Here, when "first unbalance amount S1≤set value S1o" is detected, it is determined that the imbalance of the laundry is small, and the process proceeds to step S14.

At step S14, the control device 27 sets the acceleration rate of the washing motor 12 to a set value (for example, 5 rpm).
/ Sec) while adjusting the duty ratio so as to achieve a second unbalance detection speed (for example, 170 rpm) from 100 rpm (see S14 in FIG. 3A). The second unbalance detection speed is the speed at which the drum 14 resonates in the vertical direction together with the water receiving tank 7 when there is no load (20
0 rpm) is experimentally obtained, and the longitudinal resonance speed 200r
pm, the control device 27 accelerates the washing motor 12 to 170 rpm.
The process moves to step S15 in FIG.

When the control device 27 proceeds to step S15, it detects the second unbalance amount S2. The second unbalance amount S2 is detected as a duty ratio when the washing motor 12 reaches the second unbalance detection speed (resonance speed), and the control device 27 determines the second unbalance amount S2. Is detected, the process proceeds to step S16, where the second unbalance amount S2 is compared with the set value S2o. Here, “second unbalance amount S2 ≦ set value S2
When "o" is detected, it is determined that the unbalance amount is small, and the routine goes to Step S17.

At step S17, the controller 27 sets the acceleration rate of the washing motor 12 to a set value (for example, 5 rpm).
/ Sec) while accelerating to the first dehydration preparation speed (for example, 340 rpm) while adjusting the duty ratio so that
A) of S17). Then, the washing motor 12 is set to 340
The motor is driven at a constant speed for a set period of time at rpm, and step S1 in FIG.
Move to 8.

At step S18, the control device 27 sets the acceleration rate of the washing motor 12 to a set value (for example, 10 rpm).
m / sec) while adjusting the duty ratio to
To the dehydration preparation speed (for example, 500 rpm) (see S18 in FIG. 3A). Then, the washing motor 12 is set to 50
At 0 rpm, the motor is driven at a constant speed for a set time, and the operation proceeds to step S in FIG.
Move to 19.

At step S19, the control device 27 sets the acceleration rate of the washing motor 12 to a set value (for example, 20 rpm).
m / sec) while accelerating to the maximum dehydration speed (eg, 1000 rpm) while adjusting the duty ratio to
The washing motor 12 is operated at the dehydrating speed for a set time (see S19 in FIG. 3A). At this time, water discharged from the laundry by centrifugal force is discharged into the water receiving tank 7 through the plurality of dehydrating holes 20 of the drum 14 and flows out of the machine through the drain valve 11.

After finishing the dehydrating operation, the controller 27 shifts to the imbalance correcting step. Here, the imbalance of the laundry is corrected based on injecting tap water or bath water into the water receiving tub 7, rotating the washing motor 12 forward and reverse at a low speed at which the laundry is tumbled, and then draining the laundry.

<Regarding the Dehydration Step (When the First Unbalance Amount S1 is Large)> The control device 27 determines in step S13 of FIG. 1 that "the first unbalance amount S1> set value S1o"
Is detected, it is determined that the imbalance of the laundry is large, and the process shifts to step S20 in FIG. 2 to execute step S3 in FIG.
Is read out. Here, when the detected capacity W is small, the process proceeds to step S21, and the washing motor 12 is set to the small capacity deceleration value while adjusting the duty ratio so that the deceleration rate of the washing motor 12 becomes a set value (for example, 11.7 rpm / sec). (For example, 65 rpm). FIG. 3 (b)
FIG. 3B shows a change in the rotation state of the washing motor 12 when the first unbalance amount S1 is large.
S21 shows how the washing motor 12 is decelerated from the first unbalance detection speed to a small capacity deceleration value.

The control device 27 controls the washing motor 12 to operate at 65 rpm.
When the speed is reduced to m, the process proceeds to step S22 in FIG. 2, and the rotation speed of the washing motor 12 is reduced by 1 rpm over 1 second to fix the duty ratio. These steps S21
At the time of deceleration in step S22, the laundry is tumbled in order from the smaller laundry according to the decrease in the centrifugal force (deceleration loosening operation), so that the imbalance is reduced.

After fixing the duty ratio, the control device 27 proceeds to step S23, compares the rotation speed of the washing motor 12 with a set value for small capacity (for example, 45 rpm), and
When it is detected that the rotation speed is higher than 45 rpm, the process proceeds to step S24.

After proceeding to step S24, the control device 27 detects the unbalance amount S in the same procedure as in step S12 of FIG. Then, the process proceeds to step S25 in FIG. 2, and the imbalance amount S is compared with the set value So. Here, when "imbalance amount S ≧ set value So" is detected, it is determined that the imbalance of the laundry is still large, the process returns to step S22, and steps S22 to S25 are repeated.

When the control device 27 detects that the unbalance amount S has become smaller than the set value So before the rotation speed of the washing motor 12 becomes less than 45 rpm, the control device 27 proceeds to step S2.
The process proceeds from S5 to S26. Here, the speed of the washing motor 12 is set to 100 rpm at a set acceleration rate (for example, 5 rpm / sec).
(Refer to S26 in FIG. 3B), and the step S in FIG.
It returns to 12.

When the control device 27 returns to step S12, it re-detects the first unbalance amount S1. And
When "first unbalance amount S1 ≤ set value S1o" is detected in step S13, second unbalance amount S2 is detected, and in step S13, "first unbalance amount S1" is set.
When the "set value S1o" is detected, the unbalance amount S is detected while the speed of the washing motor 12 is reduced.

Before the imbalance amount S becomes smaller than the reference value So, the control device 27 reduces the rotation speed of the washing motor 12 to four.
When it is detected that the rotation speed has dropped to less than 5 rpm, the process shifts from step S23 in FIG. 2 to step S27 in FIG. 1 to execute the reverse loosening operation. This reverse loosening operation is to stop the washing motor 12 → reverse rotation → stop in this order,
During the reverse rotation loosening operation, the laundry is entangled based on the fact that the washing motor 12 reverses at a low speed of 40 rpm for a set time (for example, 3 seconds), and the imbalance is corrected.

When the control device 27 has completed the reverse loosening operation, it returns to step S8 in FIG. 1 and adds "1" to the counter based on calculating "N ← N + 1". Then, the process proceeds to step S9, where the counter value N is set to the set value N.
When it is detected that o has not been reached, step S1
The process proceeds to 0 to S12, and the first unbalance amount S1 is detected again. Here, when "first unbalance amount S1 ≤ set value S1o" is detected, second unbalance amount S2 is detected, and when "first unbalance amount S1> reference value S1o" is detected, washing motor is detected. While decelerating 12, the unbalance amount S is detected again. Note that the broken line in FIG. 3B indicates a case where the rotation speed of the washing motor 12 is reduced to less than 45 rpm.

When the control device 27 detects that the laundry has a medium capacity in step S20 of FIG. 2, it proceeds to step S28.
Then, while adjusting the duty ratio so that the deceleration rate of the washing motor 12 becomes a set value (for example, 8.3 rpm / second), the washing motor 12 is decelerated to a medium capacity deceleration value (for example, 75 rpm).
m). Then, the process proceeds to step S29, in which the rotation speed of the washing motor 12 is reduced by 1 rpm over one second to fix the duty ratio.

After fixing the duty ratio, control device 27 proceeds to step S30. Here, the washing motor 1
The rotation speed of 2 is a set value for medium capacity (for example, 55 rpm)
When it is detected that the value is higher, the process proceeds to step S31, and the unbalance amount S is detected in the same procedure as in step S12 of FIG.

When the control device 27 detects the unbalance amount S, the process proceeds to step S32. Here, when "imbalance amount S ≧ set value So" is detected, it is determined that the imbalance of the laundry is still large, the process returns to step S29, and steps S29 to S32 are repeated.

If the control device 27 detects that the imbalance amount S has become smaller than the set value So before the rotation speed of the washing motor 12 becomes less than 55 rpm, the control device 27 proceeds to step S3.
The process moves from S2 to S33. Here, the speed of the washing motor 12 is set to 100 rpm at a set acceleration rate (for example, 5 rpm / sec).
And returns to step S12 in FIG. And
The first unbalance amount S1 is detected again, and when "the first unbalance amount S1 ≤ set value S1o", the second unbalance amount S2 is detected, and the "first unbalance amount S1" is detected.
> Set value S1o, the unbalance amount S is detected while the washing motor 12 is decelerated.

The controller 27 determines that the rotation speed of the washing motor 12 is 55 r while the unbalance amount S is larger than the set value So.
When it is detected that it has decreased to less than pm, the process proceeds from step S30 in FIG. 2 to step S27 in FIG. 1 to perform the reverse loosening operation. Then, "N ← N + 1" is calculated in step S8, and when it is detected in step S9 that the counter value N has not reached the set value No, the first unbalance amount S1 is detected again. Here, when "first unbalance amount S1 ≤ set value S1o" is detected, second unbalance amount S2 is detected, and when "first unbalance amount S1> set value S1o" is detected, washing motor is detected. While decelerating 12, the unbalance amount S is detected.

When the control device 27 detects that the laundry has a large capacity in step S20 of FIG. 2, it proceeds to step S34.
Then, while adjusting the duty ratio so that the deceleration rate of the washing motor 12 becomes a set value (for example, 6.7 rpm / sec), the washing motor 12 is moved to a large capacity deceleration value (for example, 80 rpm).
m). Then, the process proceeds to step S35, where the rotation speed of the washing motor 12 is reduced by 1 rpm over one second to fix the duty ratio.

After fixing the duty ratio, control device 27 proceeds to step S36. Here, the washing motor 1
The rotation speed of 2 is a set value for large capacity (for example, 60 rpm)
When it is detected that the value is higher, the process proceeds to step S37, and the unbalance amount S is detected in the same procedure as in step S12 of FIG. Then, the process proceeds to step S38 in FIG. 2, and when it is detected that the unbalance amount S ≧ the set value So, it is determined that the unbalance of the laundry is still large, and the process returns to step S35, and repeats steps S35 to S38.

When the control device 27 detects that the unbalance amount S has become smaller than the set value So before the rotation speed of the washing motor 12 becomes less than 60 rpm, the control device 27 proceeds to step S3.
8 to S39. Here, the speed of the washing motor 12 is set to 100 rpm at a set acceleration rate (for example, 5 rpm / sec).
And returns to step S12 in FIG. And
The first unbalance amount S1 is detected again, and when "the first unbalance amount S1 ≤ set value S1o", the second unbalance amount S2 is detected, and the "first unbalance amount S1" is detected.
> Set value S1o ", the unbalance amount S is detected again while the speed of the washing motor 12 is reduced.

The control device 27 controls the speed of the washing motor 12 to 60 rpm while the unbalance amount S is larger than the reference value So.
When it is detected that it has decreased to less than pm, the process proceeds from step S36 in FIG. 2 to step S27 in FIG. 1 to perform the reverse loosening operation. Then, "N ← N + 1" is calculated in step S8, and when it is detected in step S9 that the counter value N has not reached the set value No, the first unbalance amount S1 is detected again. Here, when "first unbalance amount S1 ≤ set value S1o" is detected, second unbalance amount S2 is detected, and when "first unbalance amount S1> set value S1o" is detected, washing motor is detected. While decelerating 12, the unbalance amount S is detected again.

<About the dehydration process (when the second unbalance amount S2 is large)> When the control device 27 detects "the second unbalance amount S2> set value S2o" in step S16 of FIG. 1, the control unit 27 proceeds to step S27. Transfer and perform reverse loosening operation. Then, “N ← N + 1” is calculated in step S8, and when it is detected in step S9 that the counter value N has not reached the set value No, the first unbalance amount S
Rediscover 1

<About the dehydration step (when the first unbalance amount S1 and the second unbalance amount S2 are not improved)> The counter value is maintained without the first unbalance amount S1 or the second unbalance amount S2 being improved. N is the set value N
If the number has reached o, the control device 27 shifts from step S9 in FIG. 1 to the unbalance correction step. And the water receiving tank 7
Tap water or bath water is injected into the inside of the washing machine, and the washing motor 12 is rotated forward and backward at a low speed and then drained, thereby correcting the imbalance of the laundry.

According to the above embodiment, the drum 14 is driven at a plurality of different speeds (40 rpm, 70 rpm in step S11) slower than the first unbalance detection speed (100 rpm).
After rotating at m), acceleration was made to the first unbalance detection speed. For this reason, the laundry gradually disperses to the outer peripheral portion in the drum 14 while being tumbled in the drum 14, so that large vibration and noise are prevented from occurring when the first imbalance is detected.

Further, the capacity W was detected before detecting the imbalance of the laundry, and the dehydration operation was started with the starting torque Tr2 corresponding to the detected capacity W after detecting the imbalance of the laundry. Therefore, an appropriate starting torque Tr2 according to the detected capacity W is set, so that the laundry capacity and the starting torque Tr2 are set.
The laundry is prevented from clumping in the drum 14 at the start of the spin-drying operation due to the poor balance between the washing and the vibration, and the occurrence of vibration and noise is prevented.

When the first unbalance amount S1 is larger than the unbalance determination value S1o, the drum 14 is moved to the first position.
When the unbalance amount S of the laundry at the time of deceleration becomes smaller than another unbalance determination value So (when the looseness of the laundry at the time of deceleration becomes larger than the looseness determination value). The drum 14 is accelerated to the first unbalance detection speed and the first unbalance amount S1
Was detected again. For this reason, when the first unbalance amount S1 is large, the laundry is tumbled based on the deceleration of the drum 14, and the imbalance is corrected, so that generation of large vibration and noise is reliably prevented. In addition, the deceleration loosening operation is performed only when the imbalance of the laundry is large, so that the deceleration loosening operation is not performed irrespective of the amount of unbalance of the laundry, and waste of operation time is prevented.

Further, before detecting the first unbalance amount S1, the capacity W of the laundry is detected. When the first unbalance amount S1 is larger than the unbalance determination value S1o, the laundry capacity W is calculated at a rate corresponding to the detected capacity W. The drum 14 was decelerated to a speed range corresponding to the detected capacity W. Therefore, it is possible to prevent the laundry from being excessively entangled based on suddenly decelerating a small amount of laundry, or from being unraveled sufficiently due to slow deceleration of a large amount of laundry. Therefore, the laundry is surely unraveled.

After the first unbalance amount S1 is detected, the washing motor 12 is moved from the first unbalance detection speed to the second unbalance detection speed (near the resonance speed of the water receiving tank 7).
And the second unbalance amount S2 is detected. At the second unbalance detection speed, the vertical vibration of the drum 14 is large, and the load on the washing motor 12 is high. For this reason, the imbalance of the laundry is easily reflected on the rotation state of the washing motor 12, and the detection accuracy of the imbalance increases.

In particular, when laundry near the rated amount is loaded in the drum 14, the laundry is densely packed in the drum 14.
When the drum 14 is rotated at a high speed, the drum 1 is rotated at a high speed.
There is a temporal difficulty in detecting the rotation unevenness (rotation time Tn) of No. 4. However, since the second unbalance amount S2 is detected based on the duty ratio of the washing motor 12 in a state where the drum 14 is rotated at the vertical resonance speed, the unbalance is detected without detecting the rotation time Tn of the drum 14. Can be detected with high accuracy.

The resonance speed 20 of the water receiving tank 7 when there is no load is set.
0 rpm is determined by the mass of the water receiving tank 7 and the like and the spring force of the damper 4. Therefore, when the capacity of the laundry is small and the sinking amount of the water receiving tank 7 is small, the gap between the water receiving tank 7 and the top plate of the cabinet 1 is small, and the water receiving tank 7 may interfere with the top plate of the cabinet 1 due to vibration. There is. However, since the second unbalance detection speed 170 rpm is set slightly lower than the resonance speed 200 rpm, the water receiving tank 7 is prevented from interfering with the top plate of the cabinet 1 due to vibration.

Further, since the drum 14 is accelerated to the second unbalance detection speed at a small rate of 5 rpm / sec, the liquid is less likely to be biased in the balancer 15 when the drum 14 is accelerated to the second unbalance detection speed. Become. For this reason, the vibration of the drum 14 at the time of detecting the second imbalance is prevented from increasing due to the influence of the bias of the liquid. Is reliably prevented. Moreover, since it is difficult for the bias of the liquid to be reflected in the second unbalance amount S2,
The detection accuracy of the second unbalance amount S2 is further improved.

In the above embodiment, when the drum 14 is accelerated to the second unbalance detection speed, the acceleration rate (step S14 in FIG. 1) is the same as the preceding and subsequent acceleration rates (steps S11 and S17). Although set to 5 rpm / sec, the present invention is not limited to this.
The acceleration rate may be set to be smaller than the acceleration rate in Step 11 and the acceleration rate in Step S17.

In the above embodiment, the drum 14
Are arranged in a horizontal state, but the present invention is not limited to this. For example, they may be arranged in a front-up slope state or a rear-up slope state. In the above embodiment, the washing motor 12 directly drives the drum 14. However, the present invention is not limited to this. For example, the washing motor 12 is driven via a reduction gear mechanism, a speed increasing gear mechanism, a belt transmission mechanism, and the like. The configuration may be such that:

In the above embodiment, before the first unbalance amount S1 of the laundry is detected, the drum 14 is moved four times.
It was rotated at the set speed of 0 rpm and 70 rpm,
The rotation speed is not limited to this, and the rotation may be performed at three or more different speeds, for example, less than 100 rpm.

In the above embodiment, the second unbalance detection speed is set to 170 rpm which is slightly lower than the resonance speed.
However, the present invention is not limited to this. For example, when the detected capacity W of the laundry is close to the rated load, the resonance speed may be set to be slightly higher than the resonance speed. In this case, since the sinking amount of the water receiving tank 7 becomes large, the gap between the water receiving tank 7 and the top plate of the cabinet 1 becomes large. Therefore, the water receiving tank 7 has the cabinet 1
Therefore, there is no problem even if the second unbalance detection speed is increased to the resonance speed of 200 rpm.

[0080]

As is clear from the above description, the drum type washing machine of the present invention has the following effects. Claim 1
According to the means described in (2) and (3), the drum is rotated at a plurality of different speeds lower than the unbalance detection speed and then accelerated to the unbalance detection speed. As a result, the laundry gradually disperses to the outer peripheral portion of the drum while being tumbled in the drum, thereby preventing the occurrence of large vibration and noise when detecting imbalance. According to the means of claim 3, the weight is detected before detecting the imbalance of the laundry, and the dehydration operation is performed with the starting torque according to the detected weight after detecting the imbalance of the laundry. The laundry is prevented from clumping in the drum at the start of the spin-drying operation due to the poor balance between the weight of the object and the starting torque, thereby preventing the occurrence of vibration and noise.

According to the fourth aspect of the present invention, when the imbalance of the laundry is large, the drum is decelerated from the unbalance detection speed, and when the unraveling of the laundry during deceleration is large, the drum is decelerated at the unbalance detection speed. Accelerated to re-detect the imbalance. Therefore, the laundry is tumbled based on the deceleration of the drum, and the imbalance is corrected, so that the occurrence of large vibration and noise is reliably prevented. According to the fifth aspect of the present invention, the weight is detected before detecting the imbalance of the laundry, and when the imbalance is large, the drum is decelerated in a form corresponding to the detected weight. Done in

According to the means of claim 6, after detecting the imbalance of the laundry, the washing motor is accelerated from the unbalance detection speed to the vicinity of the resonance speed of the water receiving tub, and the imbalance is detected again. For this reason, the imbalance of the laundry is easily reflected on the rotation state of the washing motor, so that the imbalance of the laundry is accurately detected based on the rotation state near the resonance speed of the washing motor. According to the seventh aspect of the present invention, the drum is accelerated to near the vertical resonance speed of the water receiving tank at a smaller rate than before and after the drum, so that the vibration near the resonance speed of the drum is caused by the imbalance of the liquid. Is prevented from increasing.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention (flow chart showing control contents in a dehydration step of a control device).

FIG. 2 is another flowchart showing the control contents of the control device during the dehydration step.

FIG. 3 is a diagram showing a rotation state of a washing motor during a spin-drying process (a is a rotation state when the first unbalance amount and the second unbalance amount are small, and b is a case where the first unbalance amount is large). Diagram showing the rotation state of

FIG. 4 is a block diagram showing an electrical configuration.

FIG. 5 is a side view showing the internal configuration of the washing machine in a state in which a cabinet is broken.

[Explanation of symbols]

Reference numeral 7 denotes a water receiving tank, 12 denotes a washing motor, 14 denotes a drum, 15 denotes a balancer, and 27 denotes a control device (control means).

Claims (7)

[Claims] 1. A water receiving tank into which water for washing is poured, a drum housed in the water receiving tank and into which laundry is loaded, a washing motor for rotating the drum about a horizontal axis, Control means for controlling the driving of the washing motor, wherein the control means rotates the drum at a plurality of different speeds slower than when the unbalance is detected before detecting the unbalance of the laundry. Type washing machine. 2. The control device according to claim 1, wherein the control unit controls the speed of the drum to be less than 50 rpm and a predetermined speed before detecting the imbalance of the laundry.
The drum type washing machine according to claim 1, wherein the drum type washing machine is rotated at a set speed of 0 rpm or more. 3. The control means detects the weight of the laundry before detecting the imbalance of the laundry, and after detecting the imbalance of the laundry, performs the dehydration operation with the starting torque according to the detected weight of the laundry. 3. The drum type washing machine according to claim 1, wherein the washing is performed. 4. The control means decelerates the drum from the unbalance detection speed when the unbalance of the laundry is larger than the unbalance determination value, and activates the drum when the unraveling of the laundry during the deceleration becomes larger than the unbalance determination value. The drum-type washing machine according to any one of claims 1 to 3, wherein the imbalance of the laundry is detected again by accelerating to an unbalance detection speed. 5. The control means detects the weight of the laundry before detecting the imbalance of the laundry, and when the unbalance of the laundry is larger than the unbalance determination value, unloads the drum in a form corresponding to the detected weight. The drum type washing machine according to claim 4, wherein the speed is reduced from a balance detection speed. 6. The control means, after detecting the imbalance of the laundry, accelerates the washing motor from the unbalance detection speed to near the vertical resonance speed of the water receiving tub, and controls the imbalance of the laundry by rotating the washing motor. The drum-type washing machine according to any one of claims 1 to 5, wherein the detection is performed again based on the state. 7. The drum is provided with a balancer in which a liquid is sealed in a hollow body, and the control means accelerates the drum near a longitudinal resonance speed of the water receiving tank at a rate smaller than before and after. The drum type washing machine according to claim 6, characterized in that: