washing machine

Abstract

To provide a washing machine capable of safely shifting to post-stop operation after speed reduction of rotation of a washing and dewatering tub.SOLUTION: A washing machine according to the present disclosure includes: an outer tub provided so as to be able to store water; a washing and dewatering tub provided inside the outer tub, for accommodating laundry; an electric motor serving as a driving source of rotation of the washing and dewatering tub; and a control section for controlling the rotation of the electric motor and controlling operation including a first process. In speed reduction of the washing and dewatering tub during the first process, when a first time determined according to a cloth amount of the laundry elapses after a magnitude of a phase current of the electric motor or an estimated rotation speed of the washing and dewatering tub reaches a prescribed value or less, the control section enables execution of post-stop operation.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a washing machine.

Background Art

[0002] Patent Document 1 discloses a washing machine that estimates the motor rotation speed of a motor using a sensorless position estimation method that estimates the magnetic pole position of a rotor by supplying a single pulse voltage or current at predetermined intervals via an inverter circuit and measuring the response current of the motor.

Prior Art Literature

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] The present disclosure provides a washing machine that can safely transition to post-stop operation after the rotation of the washing and dewatering tub is decelerated.

Means for Solving the Problem

[0005] The washing machine according to the present disclosure includes: an outer tub configured to be capable of storing water; a washing and dewatering tub provided inside the outer tub and configured to accommodate laundry; an electric motor serving as a drive source for rotating the washing and dewatering tub; and a control unit configured to control rotation of the electric motor and control an operation including a first process. During deceleration of the washing and dewatering tub in the first process, the control unit enables execution of post-stop operation when a first time period, which is determined according to the laundry amount of the laundry, elapses after the magnitude of the phase current of the electric motor or the estimated rotation speed of the washing and dewatering tub falls to a predetermined value or lower.

Effects of the Invention

[0006] The washing machine according to the present disclosure can safely transition to post-stop operation after the rotation of the washing and dewatering tub is decelerated. [Brief explanation of the drawing]

[0007] [Figure 1] Cross-sectional view of the washing machine in Embodiment 1 [Figure 2] Control block circuit diagram of the washing machine in Embodiment 1 [Figure 3] Detailed circuit diagram of the washing machine power supply circuit in Embodiment 1 [Figure 4] Block diagram of the motor control unit and motor of the washing machine in Embodiment 1 [Figure 5] A block diagram detailing the internal configuration of the current vector setter of the washing machine in Embodiment 1. [Figure 6] Flowchart of the washing machine drum rotation operation from start to stop in Embodiment 1 [Figure 7] A graph showing the relationship between the washing machine's time, phase current during braking, and rotation speed in Embodiment 1. [Figure 8] A graph showing the relationship between the fabric load determination value of the washing machine and the waiting time until the machine stops in Embodiment 1. [Figure 9] Flowchart of the washing machine drum rotation operation from start to stop in Embodiment 2 [Figure 10] This graph shows the relationship between the washing machine's time, the target rotation speed, estimated rotation speed, and torque current when transitioning from acceleration to constant speed rotation in Embodiment 3. [Figure 11] This graph shows the relationship between the average torque current during constant rotation of the washing machine in Embodiment 3 and the waiting time until the machine stops. [Figure 12] Graph showing the relationship between washing machine time, target rotation speed during acceleration, estimated rotation speed, and torque current in Embodiment 4. [Figure 13] Graph showing the relationship between the average torque current during acceleration of the washing machine in Embodiment 4 and the waiting time until stopping is complete. [Figure 14] Graph showing the relationship between washing machine time and estimated rotation speed during braking in Embodiment 5. [Figure 15]Graph showing the relationship between deceleration time during braking of the washing machine in Embodiment 5 and waiting time until stopping is complete. [Modes for carrying out the invention]

[0008] (Knowledge and other information that formed the basis of this disclosure) At the time the inventors conceived of this disclosure, there was a technology for controlling the rotation of the washing and spinning tub in a sensorless manner, without a position sensor to detect the rotation speed of the washing and spinning tub in a washing machine.

[0009] In sensorless systems, it is difficult to estimate the rotational speed and phase of the washing / spinning tub and the motor when the washing / spinning tub is rotating at low speed. When stopping the rotation of the washing / spinning tub, it is difficult to estimate the rotational speed and phase of the washing / spinning tub and the motor in the low-speed rotation range. Therefore, it is difficult to determine which direction to control the current to act as a reverse torque brake, making it difficult to control the brake and to correctly estimate the rotational speed just before stopping and when to stop.

[0010] In washing machines like drum-type washing machines, where the central axis of the washing and spinning tub extends almost horizontally, when the washing and spinning tub rotates at a low speed, the laundry tends to accumulate at the bottom of the tub, making it easier to stop the tub from rotating.

[0011] On the other hand, in washing machines like vertical washing machines, where the central axis of the washing and spin-drying tub extends vertically, the laundry rests on the pulsator inside the tub. While the rotation of the pulsator is easy to stop, the rotation of the washing and spin-drying tub is difficult to stop due to the influence of inertia (moment of inertia). In particular, when there is a large amount of laundry or when the washing and spin-drying tub contains water, the rotation of the washing and spin-drying tub is difficult to stop due to the large inertia. As a result, the stopping time until the rotation of the washing and spin-drying tub stops becomes longer, making it difficult to estimate when the rotation of the washing and spin-drying tub will stop.

[0012] Under such circumstances, the inventors have found that there is a problem of the need to prevent unsafety and equipment failures caused by the washing and dewatering tub being presumed to have stopped even when the washing and dewatering tub has not stopped, and have come to constitute the subject matter of the present disclosure in order to solve this problem.

[0013] Accordingly, the present disclosure provides a washing machine that can accurately estimate the stop of rotation of the washing and dewatering tub according to the amount of laundry, and can safely transition to post-stop operations.

[0014] Hereinafter, embodiments will be described in detail with reference to the drawings. However, unnecessarily detailed descriptions may be omitted. For example, detailed descriptions of well-known matters or redundant descriptions of substantially the same configurations may be omitted.

[0015] It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims thereby.

[0016] (Embodiment 1) Hereinafter, Embodiment 1 will be described with reference to FIG. 1 to FIG. 8.

[0017] [1-1. Configuration] [1-1-1. Configuration of Washing Machine] FIG. 1 shows a cross-sectional view of the washing machine, and FIG. 2 shows a control block circuit diagram of the washing machine.

[0018] As shown in Figure 1, the washing machine 1 comprises a washing machine outer frame 2, a water receiving tank 3 provided inside the washing machine outer frame 2, and a washing and dewatering tank 4 rotatably provided inside the water receiving tank 3. The water receiving tank 3 is provided to hold water and is vibration-dampingly supported to the washing machine outer frame 2 via a suspension 3a. The washing and dewatering tank 4 is provided to accommodate laundry. Water passage holes 4a are provided in the wall surface of the washing and dewatering tank 4 to allow water to pass between it and the water receiving tank 3. A pulsator 5 for agitating laundry is provided at the inner bottom of the washing and dewatering tank 4 so as to be rotatable from side to side. The washing machine 1 is a so-called vertical washing machine in which the central axes of the water receiving tank 3 and the washing and dewatering tank 4 are provided to extend in the vertical direction.

[0019] Inside the outer frame 2 of the washing machine are a motor 6, a belt 7, a transmission means 8, and a control device 9. The transmission means 8 includes a clutch that switches the power from the motor 6 between the integrated rotation of the washing / spinning tub 4 and the pulsator 5, and the rotation of the pulsator 5 alone, and a brake that suppresses the rotation of the washing / spinning tub 4. The rotation of the motor 6 rotates or brakes the washing / spinning tub 4 and the pulsator 5 via the belt 7 and the transmission means 8. The control device 9 controls the overall operation of the washing machine 1.

[0020] An operation display unit 10 is provided on the upper surface of the washing machine outer frame 2. The operation display unit 10 includes an input setting means 10a for the user to set the desired washing course, start the operation, pause the operation, etc., and a display means 10b that displays the progress of the operation and various information using an emitting element such as an LED or LCD.

[0021] An opening 2a is formed on the upper surface of the washing machine outer frame 2, allowing laundry to be loaded into and unloaded from the washing and spin-drying tub 4. A lid 11 is provided to cover the opening 2a in a way that allows it to be opened and closed. A magnet 14 is provided at the front end of the lid 11 and is positioned opposite a magnetic sensor 15 provided on the upper surface of the washing machine outer frame 2. The magnetic sensor 15 is made up of a Hall IC or the like and detects the opening and closing of the lid 11 by the magnetic field lines of the magnet 14 provided on the lid 11. The magnet 14 and the magnetic sensor 15 function as a lid opening / closing detection means 16.

[0022] The lid 11 has a ring-shaped locking portion 17 at its front end. When the lid 11 is closed, a locking pin 18 can be fitted into the ring-shaped locking portion 17 to lock the lid 11 in the closed position. The locking portion 17 and the locking pin 18 constitute the lid locking mechanism 19. The lid locking mechanism 19 is composed of a solenoid and a heart cam, and can switch between a locked state and an unlocked state each time power is supplied, and can maintain that state even after the power is cut off.

[0023] A water supply valve 20 is provided at the top of the washing machine 1. The water supply valve 20 controls the supply of water to the water receiving tank 3.

[0024] A drain valve 21 and a geared motor 21a are provided at the bottom of the washing machine 1. The geared motor 21a controls the opening and closing of the drain valve 21. When the drain valve 21 is open, the water in the water receiving tank 3 is discharged to the outside of the washing machine 1 through the drainage path.

[0025] [1-1-2. Configuration of the control device and motor] As shown in Figure 2, the control device 9 includes a motor 6, a drain valve 21 (geared motor 21a), The control unit 22 consists of a microcomputer that controls the operation of the water supply valve 20 and other components, and sequentially controls a series of processes such as washing, rinsing, and spinning. Based on information input by the user via the input setting means 10a, when the start of operation is set in the input setting means 10a, the control unit 22 receives data from the water level detection means, lid opening / closing detection means 16, etc., and controls the operation of the geared motor 21a, lid locking means 19, water supply valve 20, etc., via the switching control means 23a and switching means 23 to execute the operation. Note that the operation may include some or all of the washing process, rinsing process, spinning process, drying process, and tub cleaning process. In each process, the control unit 22 drives the motor 6 to rotate the washing / spinning tub 4 and pulsator 5.

[0026] The control unit 22 supplies current to the motor 6 via the power supply circuit 24. The motor 6 is a DC brushless motor, and although not shown, it consists of a stator having three phase windings and a rotor with two-pole permanent magnets arranged on a ring. The stator is constructed by winding the first winding 6a (U phase), the second winding 6b (V phase), and the third winding 6c (W phase), which constitute the three phase windings, around an iron core with slots.

[0027] Next, Figure 3 shows a detailed circuit diagram of the power supply circuit 24 in this embodiment 1.

[0028] The switching elements 55, 56, 57, 58, 59, and 60 are each composed of an IGBT (Insulated Gate Bipolar Transistor) and a diode connected in antiparallel between its collector and emitter terminals. The drive circuit 61 is connected to the gate terminal of each switching element to control its on / off state.

[0029] The DC power supply 63 performs full-wave rectification or voltage doubling rectification of the AC commercial power supply. Shunt resistors 66, 67, and 68 of approximately 50 milliohms are connected between the switching elements 58, 59, and 60 on the low-potential side and the negative terminal of the DC power supply 63. The amplification circuit 70 amplifies the voltage generated in proportion to the current flowing through the shunt resistors 66, 67, and 68. The level shift is performed so that the zero current is approximately 2.5V, so that it falls within the range of the AD terminal of the microcomputer (not shown), and this is transmitted to the control unit 22 as the output of the current sensing circuit 71.

[0030] In this embodiment 1, the current sensing circuit 71 has shunt resistors 66, 67, and 68, but other configurations are also acceptable. For example, a single shunt resistor can be used to output the line currents of each of the three phases UVW at multiple timings within the carrier period of PWM (Pulse Width Modulation), and then separate them into three phases by addition and subtraction. Alternatively, a component called a DCCT (DC Current Transformer), which converts currents of frequencies from DC to high frequencies into voltage via magnetic coupling such as a Hall element, can be inserted into each of the three lines UVW that serve as input to the motor.

[0031] Next, Figure 4 shows a block diagram of the control device 9 and motor 6 of the washing machine 1.

[0032] The control device 9 obtains the rotational speed of the washing and spin-drying tub 4 using a speed calculation method called sensorless. Sensorless and vector control will be described below. The current control unit 105 includes a power supply circuit 24, a first coordinate transducer 100, error subtractors 102 and 103, a current error amplifier 101, and a second coordinate transducer 104, as shown below. The current sensing circuit 71 of the power supply circuit 24 supplies current to the windings 97, 98, and 99 of each phase of the motor 6.

[0033] The first coordinate converter 100 decomposes the output currents Iu, Iv, and Iw of the power supply circuit 24 into Iγ and Iδ, which are the γδ components of the rotation coordinate (estimated d and estimated q components), along with the θ value. The difference subtractor 102 calculates the error between the current command values ​​Iγr and Iγ in γδ coordinates. The error subtractor 103 also calculates the error between the current command values ​​Iδr and Iδ in γδ coordinates. The current error amplifier 101 outputs voltage commands Vγ and Vδ by applying the PI (proportional + integral) element to these errors. The second coordinate converter 104 uses θ to perform an inverse transformation to convert the voltage values ​​of each phase of the stationary coordinate system (UVW). As described above, the current control unit 105 controls the γδ current. Here, the first coordinate converter 100 and the second coordinate converter 104 perform calculations using the following equations (Equation 1) and (Equation 2), respectively. Note that this is just one example; various equations using trigonometric functions can be used, and conversions between stationary and rotating coordinates, and inverse conversions, can be performed.

[0034]

number

[0035]

number

[0036] Furthermore, the phase error detector 107 calculates the phase θ by inputting Vγ, Iγ, and Iδ, as shown in (Equation 3). Here, Ra is the resistance value of windings 97, 98, and 99, and Lq is the q-axis inductance of motor 6.

[0037]

number

[0038] From the above, the speed calculator 108 outputs the calculated angular velocities ω and ω1 as shown in (Equation 4) and (Equation 5).

[0039]

number

[0040]

number

[0041] ω1 is output by the integrator 110 as a time integral θ to the first coordinate transformer 100 and the second coordinate transformer 104, as shown in (Equation 6), where θ becomes the estimated phase.

[0042]

number

[0043] Meanwhile, ω, along with ωr, which is the output value of the speed command means 111, is input to the subtractor 112. Then, as a speed error with respect to the command speed, the speed error amplifier 113 performs error amplification in the form of PI (proportional + integral). As a result, Iγra and Iδra are output. During powering, the current vector setter 115 inputs Iγra and Iδra as Iγr and Iδr, respectively, to the current control unit 105. As a result, vector control and speed control are established, and the motor 6 is driven.

[0044] Next, Figure 5 shows a block diagram that details the internal configuration of the current vector setter 115 in this embodiment 1.

[0045] The current vector setter 115 includes switches 118 and 119. Switches 118 and 119 are switchable between side a (speed control) and side b (constant torque current control). In other words, side a is connected when speed control is performed using torque according to the deviation between the target and current rotational speed, and side b is connected when torque current constant control is performed using a constant torque.

[0046] [1-2. Operation] The operation and function of the washing machine 1, configured as described above, will now be explained.

[0047] The operation of washing machine 1 will be explained based on Figure 6.

[0048] When the control unit 22 receives an instruction to start operation from the input setting means 10a, the control unit 22 starts operating the washing machine 1 (step S10). Starting operation includes starting the operation of a washing course and resuming operation that was previously paused.

[0049] When operation starts in step S10, the control unit 22 performs a fabric quantity determination (step S100). In the fabric quantity determination in step S100, the control unit 22 rotates the washing and spin-drying tub 4 and obtains a fabric quantity determination value M as the amount of laundry contained in the washing and spin-drying tub 4 from the current flowing to the motor 6. The control unit 22 may obtain the fabric quantity determination value M by receiving it directly from the user via the input setting means 10a, or it may obtain it from the amount of fabric detected by the fabric quantity detection unit, which is provided to detect the amount of fabric.

[0050] Next, the lid opening / closing detection means 16 detects whether the lid 11 is open or closed (step S101). If the lid opening / closing detection means 16 detects that the lid 11 is closed (if the answer is YES in step S101), the control unit 22 drives the lid locking means 19 to lock the lid 11 in a closed position so that it cannot be opened, and starts the tub rotation operation (step S103). The tub rotation operation refers to the operation in which the control unit 22 drives the motor 6 to rotate the washing and spin-drying tub 4.

[0051] After the washing and spin-drying tub 4 starts rotating, the control unit 22 determines whether or not it has received a tub rotation stop instruction (step S104). If the control unit 22 has received a tub rotation stop instruction (if it is YES in step S104), the control unit 22 starts brake control to decelerate the rotation of the washing and spin-drying tub 4 (step S105). Note that receiving a tub rotation stop instruction in step S104 means that the control unit has received an instruction from the user to temporarily suspend or end the operation via the input setting means 10a or a terminal provided to communicate with the washing machine 1. This includes, at the end of operation or during a series of operations, the control unit 22 stopping the rotation of the washing and dewatering tub 4 in order to perform the following actions, and detecting an abnormality such as a power outage.

[0052] In step S105, during brake control, the control unit 22 slows down the rotation of the washing and spin-drying tub 4 by applying a reverse torque to the motor 6. The method of applying a reverse torque to the motor 6 may be a so-called short-circuit brake, in which the switching elements 58, 59, and 60 on the low-potential side of the motor 6 short-circuit the three-phase windings (U-phase, V-phase, and W-phase) and the negative terminal of the DC power supply 63, or it may be controlled by applying a reverse torque current to the motor 6.

[0053] During brake control, the control unit 22 determines whether the magnitude of the phase currents (Iu, Iv, Iw) of all phases (U phase, V phase, W phase) in the motor 6 is less than or equal to a predetermined current value I0 (for example, 0.4A or less) (step S106). If the magnitude of the phase currents of all phases in the motor 6 is less than or equal to the predetermined current value I0 (if YES in step S106), the control unit 22 determines whether a waiting time Tw has elapsed since the magnitude of the phase currents of all phases in the motor 6 became less than or equal to the predetermined current value I0 (step S107). The waiting time Tw will be described in detail later, but it is the time from when the magnitude of the phase currents of all phases in the motor 6 became less than or equal to the predetermined current value I0 until it is estimated that the rotation of the washing and dewatering tub 4 has stopped. If the magnitude of the phase currents of all phases in the motor 6 becomes less than or equal to a predetermined current value I0, and a waiting time Tw has elapsed (if the answer is YES in step S107), it is estimated that the rotation of the washing and spin-drying tub 4 has stopped (step S108), and the control unit 22 executes post-stop operations (step S109).

[0054] As an operation after stopping in step S109, if the user has given an instruction to temporarily suspend or terminate the operation in step S104, or if the series of operations has ended, the control unit 22 releases the lock on the lid 11 by the lid locking means 19. If operation continues after step S109, the control unit 22 may switch the clutch to make the pulsator 5 rotatable, or restart the motor 6 to perform a tub rotation operation to rotate the washing and dewatering tub 4. The control unit 22 may also open the water supply valve 20 to supply water, or control the geared motor 21a to open the drain valve 21. Furthermore, if an abnormality such as a power outage is detected in step S104, the control unit 22 may restart the motor 6 to perform a tub rotation operation to rotate the washing and dewatering tub 4, or it may perform an abnormality notification via the display means 10b and notification means such as a buzzer.

[0055] Figure 7 illustrates the relationship between the phase current of the motor 6 and the rotational speed of the washing and spin-drying tub 4 during brake control.

[0056] When the rotation of the washing and spin-drying tub 4 is reduced and its rotational speed decreases, the magnitude of the phase currents (Iu, Iv, Iw) flowing through the motor 6 decreases. In sensorless control, it is not possible to detect the actual rotational speed of the washing and spin-drying tub 4 when it is rotating at a low speed. Therefore, in the washing machine 1 of this embodiment, when the magnitude of the phase currents (Iu, Iv, Iw) of all phases (U phase, V phase, W phase) in the motor 6 falls below a predetermined current value I0, it is estimated that the rotational speed of the washing and spin-drying tub 4 has decreased, and when a waiting time Tw has elapsed from that point, it is estimated that the washing and spin-drying tub 4 has stopped. Thus, although it is not possible to detect that the rotation of the washing and spin-drying tub 4 has stopped in sensorless control, the control unit 22 can estimate that the washing and spin-drying tub 4 has stopped based on the magnitude of the phase currents and the waiting time Tw, and safely proceed to post-stop operation (step S108 in Figure 6). In this embodiment, the control unit 22 compares the magnitude of the phase currents (Iu, Iv, Iw) of all phases (U phase, V phase, W phase) in the motor 6 with the relationship between them and a predetermined current value I0 or less. However, the determination may also be made based on the magnitude of one or two of the phase currents.

[0057] Next, we will explain the relationship between the fabric quantity judgment value M and the waiting time Tw using Table 1 and Figure 8.

[0058] [Table 1]

[0059] The fabric load determination value M has a positive correlation with the inertia of the washing and spin-drying tub 4. Therefore, if the fabric load determination value M is large, the rotation of the washing and spin-drying tub 4 is less likely to stop, and the time required for the rotation of the washing and spin-drying tub 4 to stop is longer. On the other hand, if the fabric load determination value M is small, the rotation of the washing and spin-drying tub 4 stops more easily, and the time required for the rotation of the washing and spin-drying tub 4 to stop is shorter. For this reason, as shown in Table 1, the waiting time Tw is set according to the fabric load determination value M. When the fabric load determination value M is large, the waiting time Tw is set to be long, and when the fabric load determination value M is small, the waiting time Tw is set to be short. This makes it possible to reduce the difference between the estimated stop time, which is the estimated time when the rotation of the washing and spin-drying tub 4 is estimated to have stopped after the waiting time Tw has elapsed since the magnitude of the phase current (Iu, Iv, Iw) fell below a predetermined current value I0, and the actual stop time when the rotation of the washing and spin-drying tub 4 stops. As shown in Figure 8, if we let the amount of fabric judged value M be X1 and the waiting time Tw be Y1, we can set the relationship between X1 (amount of fabric judged value M) and Y1 (waiting time Tw) by setting the function Y1 = A1 × X1^2 + B1 × X1 + C1 (parameters A1, B1, C1). By appropriately setting parameters A1, B1, and C1, it becomes possible to set the waiting time Tw in accordance with minute differences in the amount of fabric judged value M, thereby reducing the difference between the estimated stop time and the actual stop time of the washing and spin-drying tub 4.

[0060] Next, using Table 2, we will explain the relationship between the fabric quantity judgment value M, including more detailed conditions, and the waiting time Tw.

[0061] [Table 2]

[0062] As described above, the fabric load determination value M has a positive correlation with the inertia of the washing and spin-drying tub 4. Therefore, if the fabric load determination value M is large, the rotation of the washing and spin-drying tub 4 is less likely to stop, and the time required for the rotation of the washing and spin-drying tub 4 to stop is longer. On the other hand, if the fabric load determination value M is small, the rotation of the washing and spin-drying tub 4 stops more easily, and the time required for the rotation of the washing and spin-drying tub 4 to stop is shorter. For this reason, in Table 2, the waiting time Tw is set according to the fabric load determination value M, with the waiting time Tw being set longer when the fabric load determination value M is large, and the waiting time Tw being set shorter when the fabric load determination value M is small. This makes it possible to reduce the difference between the estimated stop time, which is the estimated time when the rotation of the washing and spin-drying tub 4 is estimated to have stopped after the waiting time Tw has elapsed since the magnitude of the phase current (Iu, Iv, Iw) fell below a predetermined current value I0, and the actual stop time when the rotation of the washing and spin-drying tub 4 stops.

[0063] The first course is for loads of less than 2.5 kg of laundry, and the second course is for loads of less than 5 kg of laundry. In certain courses, such as the first and second courses, where the amount of laundry that can be loaded is limited, the waiting time Tw may be set based on the amount of laundry pre-set for the course, rather than the amount of laundry judgment value M.

[0064] The control unit 22 performs a drum rotation operation to rotate the washing and spin-drying drum 4 during the dewatering process and the drum rotation process. The dewatering process is a process in which the drum rotation operation is performed with the drain valve 21 open and when there is no water or only a small amount of water in the water receiving tank 3 and the washing and spin-drying drum 4. On the other hand, the drum rotation process is a process in which the drum rotation operation is performed with the drain valve 21 closed and when there is water in the water receiving tank 3 and the washing and spin-drying drum 4 or when the water supply valve 20 is open and water is being supplied. Examples of the drum rotation process include the washing operation in the washing process and the rinsing operation in the rinsing process.

[0065] In the dewatering process, the drum rotation operation is performed with the water in the washing / dewatering drum 4 drained. On the other hand, in the drum rotation process, the drum rotation operation is performed with water in the washing / dewatering drum 4, that is, with the laundry containing a lot of water. Therefore, in the drum rotation process, the inertia of the washing / dewatering drum 4 is greater than in the dewatering process, making it more difficult for the washing / dewatering drum 4 to stop rotating, and the time required for the washing / dewatering drum 4 to stop rotating is longer. To address this, the waiting time Tw is set longer in the drum rotation process and shorter in the dewatering process. This reduces the difference between the estimated stop time, which is the estimated time when the rotation of the washing / dewatering drum 4 is estimated to have stopped after the waiting time Tw has elapsed since the magnitude of the phase current (Iu, Iv, Iw) fell below a predetermined current value I0, and the actual stop time when the rotation of the washing / dewatering drum 4 stops.

[0066] Furthermore, the waiting time Tw may be different depending on whether the user has given an instruction to temporarily stop operation as a tank rotation stop instruction (step S104 in Figure 6) or not.

[0067] When the user requests a temporary pause in operation as a drum rotation stop instruction, the waiting time Tw is set short because the user wants to pause the operation. This shortens the time between the user giving the instruction to pause operation and the lid locking mechanism 19 releasing the lock on the lid 11, allowing the lid 11 to be opened, in case the user wants to open the lid 11 to add more laundry. In addition, even when the user requests a temporary pause in operation, the waiting time Tw may be determined according to the amount of laundry judged or the course being run.

[0068] On the other hand, except when the user requests a temporary halt to operation as a drum rotation stop instruction, the waiting time Tw is set to be long. This prevents malfunctions and failures of the equipment caused by the machine presuming that the washing and spin-drying drum 4 has stopped rotating even though it has not actually stopped, and executing the post-stop operation (step S109 in Figure 6). For example, if the post-stop operation involves restarting the motor 6 to rotate the washing and spin-drying drum 4 again, this prevents starting failures caused by the motor 6 not being stopped when it is restarted. Also, if the post-stop operation involves switching the clutch, this prevents wear and damage to the clutch caused by switching the clutch while the washing and spin-drying drum 4 is still rotating.

[0069] [1-3. Effects, etc.] As described above, in this embodiment, the washing machine 1 comprises a washing machine outer frame 2 (casing), a water receiving tank 3 (outer tank) provided within the washing machine outer frame 2 to store water, a washing and dewatering tank 4 provided within the water receiving tank 3 to hold laundry, a motor 6 (electric motor) which is the driving source for the rotation of the washing and dewatering tank 4, and a control unit 22 which controls the rotation of the motor 6 and controls the operation including the first step. When the washing and dewatering tank 4 is decelerated during the first step, the control unit 22 enables post-stop operation after the magnitude of the phase current of the motor 6 becomes less than or equal to a predetermined current value I0 (predetermined value) and a waiting time Tw (first hour) determined according to the amount of laundry has elapsed.

[0070] This allows the waiting time Tw from when the phase current of the motor 6 falls below a predetermined value until post-stop operations can be performed to be determined according to the amount of fabric. Therefore, the stopping of the rotation of the washing and spin-drying tub 4 can be accurately estimated according to the amount of fabric, and the transition to post-stop operations can be made safely.

[0071] As in this embodiment, the control unit 22 may set the waiting time Tw to be longer as the amount of fabric increases.

[0072] As a result, the larger the amount of fabric, the longer it may take for the washing and spinning tub 4 to stop rotating, so the waiting time Tw before the operation can be performed after stopping can be set to be longer. Therefore, the stopping of the rotation of the washing and spin-drying tub 4 can be accurately estimated according to the amount of fabric, and the system can safely transition to post-stop operation.

[0073] As in this embodiment, the control unit 22 may set the waiting time Tw when the first step is performed with water in the water receiving tank 3 to be longer than the waiting time Tw when the first step is performed with the water in the water receiving tank 3 drained.

[0074] As a result, in processes performed with water in the water receiving tank 3, the inertia of the washing and spin-drying tub 4 is large, and the time it takes for the washing and spin-drying tub 4 to stop rotating may be long. Therefore, the waiting time Tw before the post-stop operation can be made available can be set to be longer. Consequently, the stopping of the rotation of the washing and spin-drying tub 4 can be accurately estimated according to the amount of fabric and the presence or absence of water in the water receiving tank 3, and the system can safely transition to the post-stop operation.

[0075] As in this embodiment, the washing machine 1 further includes a lid 11 that can open and close to cover the opening 2a formed in the outer frame 2 of the washing machine, and a lid locking means 19 that locks the lid 11 in a closed state. When the control unit 22 receives an instruction to temporarily suspend operation, after the magnitude of the phase current becomes less than or equal to a predetermined current value I0 and a waiting time Tw has elapsed, it may perform a post-stop operation which involves releasing the lock on the lid 11 using the lid locking means 19.

[0076] This allows the lid locking mechanism 19 to release the lock on the lid 11 after the rotation of the washing and spin-drying tub 4 has stopped. As a result, the user can safely open the lid 11 and remove the laundry from inside the washing and spin-drying tub 4.

[0077] As in this embodiment, the control unit 22 may set the waiting time Tw when it receives an instruction to temporarily suspend operation to be shorter than the waiting time Tw when it does not receive an instruction to temporarily suspend operation.

[0078] This allows for a shorter waiting time Tw to be set when an instruction to temporarily suspend operation is received, allowing the user to open the lid 11 by releasing the lock on the lid 11 by the lid locking means 19. Conversely, when an instruction to temporarily suspend operation is not received, a longer waiting time Tw can be set to allow for a safe transition to the post-stop operation.

[0079] As in this embodiment, if the control unit 22 has not received an instruction to temporarily suspend operation, it may restart the motor 6 as a post-stop operation after a waiting time Tw has elapsed since the magnitude of the phase current fell below a predetermined current value I0, enabling the rotation of the washing and spin-drying tub 4.

[0080] This allows the motor 6 to restart after it has estimated that the washing and spin-drying tub 4 has stopped rotating, thereby allowing the washing and spin-drying tub 4 to start rotating again. Therefore, it is possible to suppress the occurrence of startup failures that may occur when the motor 6 is restarted if it has not stopped.

[0081] As in this embodiment, the washing machine 1 further includes a pulsator 5 (agitating blade) rotatably mounted inside the washing and spin-drying tub 4, and a clutch that switches the output of the motor 6 to the rotation of the pulsator 5, or the pulsator 5 and the washing and spin-drying tub 4. The control unit 22 may, if it has not received an instruction to temporarily suspend operation, perform clutch switching as a post-stop operation after a waiting time Tw has elapsed since the magnitude of the phase current fell below a predetermined current value I0.

[0082] This allows the clutch to be switched after the rotation of the washing and spin-drying tub 4 has stopped. Therefore, wear and damage to the clutch caused by switching the clutch while the washing and spin-drying tub 4 is still rotating can be suppressed.

[0083] (Embodiment 2) Embodiment 2 will be described below with reference to Figure 9. Embodiment 2 differs from Embodiment 1 in that step S106 (Figure 6) is replaced by step 116.

[0084] [2-1. Operation] Steps up to S105 are the same as in Embodiment 1, so the explanation will be omitted.

[0085] During brake control (step S105), the control unit 22 determines whether the estimated rotation speed of the washing and spin-drying tub 4 is less than or equal to a predetermined rotation speed N0 (for example, 35 r / min). If the estimated rotation speed of the washing and spin-drying tub 4 is less than or equal to the predetermined rotation speed N0 (if YES in step S116), the control unit 22 determines whether a waiting time Tw has elapsed since the estimated rotation speed of the washing and spin-drying tub 4 became less than or equal to the predetermined rotation speed N0 (step S107). In this embodiment, the waiting time Tw is the time from when the estimated rotation speed of the washing and spin-drying tub 4 becomes less than or equal to the predetermined rotation speed N0 until it is estimated that the rotation of the washing and spin-drying tub 4 has stopped. If the waiting time Tw has elapsed since the estimated rotation speed of the washing and spin-drying tub 4 became less than or equal to the predetermined rotation speed N0 (if YES in step S107), the control unit 22 estimates that the rotation of the washing and spin-drying tub 4 has stopped (step S108), and executes post-stop operations (step S109).

[0086] In sensorless control, the control unit 22 can estimate the rotation speed of the washing and dewatering tub 4 from the magnitude of the phase current in the motor 6 when the rotation speed of the washing and dewatering tub 4 is high, but it cannot estimate the rotation speed of the washing and dewatering tub 4 when the rotation speed of the washing and dewatering tub 4 is low. If the control unit 22 sets the estimated rotation speed of the washing and dewatering tub 4 to a lower limit (for example, 30 r / min), it is desirable that the predetermined rotation speed N0 be set to a rotation speed slightly higher than the estimated lower limit.

[0087] [2-2. Effects] As described above, in this embodiment, the washing machine 1 comprises a washing machine outer frame 2 (housing), a water receiving tank 3 (outer tank) provided within the washing machine outer frame 2 to store water, a washing and dewatering tank 4 provided within the water receiving tank 3 to hold laundry, a motor 6 (electric motor) that serves as the driving source for the rotation of the washing and dewatering tank 4, and a control unit 22 that controls the rotation of the motor 6 and controls the operation including the first step. When the washing and dewatering tank 4 is decelerated during the first step, the control unit 22 enables post-stop operations after the estimated rotation speed of the washing and dewatering tank 4 falls below a predetermined rotation speed N0 (predetermined value) and a waiting time Tw (first hour) determined according to the amount of laundry has elapsed.

[0088] This allows the waiting time Tw from when the estimated rotation speed of the washing and spin-drying tub 4 falls below a predetermined value until the post-stop operation can be performed to be determined according to the amount of fabric. Therefore, the stopping of the rotation of the washing and spin-drying tub 4 can be estimated accurately according to the amount of fabric, and the system can safely transition to the post-stop operation.

[0089] As in this embodiment, the washing machine 1 further includes a lid 11 that can open and close to cover the opening 2a formed in the outer frame 2 of the washing machine, and a lid locking means 19 that locks the lid 11 in a closed state. When the control unit 22 receives an instruction to temporarily stop operation, after the estimated rotation speed of the washing and spin-drying tub 4 has fallen below a predetermined rotation speed N0 and a waiting time Tw has elapsed, it may perform a post-stop operation which involves releasing the lock on the lid 11 using the lid locking means 19.

[0090] This allows the lid locking mechanism 19 to release the lock on the lid 11 after the rotation of the washing and spin-drying tub 4 has stopped. As a result, the user can safely open the lid 11 and remove the laundry from inside the washing and spin-drying tub 4.

[0091] As in this embodiment, if the control unit 22 has not received an instruction to temporarily suspend operation, it waits for a waiting time Tw to elapse after the estimated rotation speed of the washing and spin-drying tub 4 falls below a predetermined rotation speed N0. As a post-stop operation, the motor 6 may be restarted to enable the rotation of the washing and spin-drying tub 4.

[0092] This allows the motor 6 to restart after it has estimated that the washing and spin-drying tub 4 has stopped rotating, thereby allowing the washing and spin-drying tub 4 to start rotating again. Therefore, it is possible to suppress the occurrence of startup failures that may occur when the motor 6 is restarted if it has not stopped.

[0093] As in this embodiment, the washing machine 1 further includes a pulsator 5 (agitating blade) rotatably mounted inside the washing and spin-drying tub 4, and a clutch that switches the output of the motor 6 to the rotation of the pulsator 5, or the pulsator 5 and the washing and spin-drying tub 4. The control unit 22 may, if it has not received an instruction to temporarily stop operation, perform clutch switching as a post-stop operation after a waiting time Tw has elapsed since the estimated rotation speed of the washing and spin-drying tub 4 fell below a predetermined rotation speed N0.

[0094] This allows the clutch to be switched after the rotation of the washing and spin-drying tub 4 has stopped. Therefore, wear and damage to the clutch caused by switching the clutch while the washing and spin-drying tub 4 is still rotating can be suppressed.

[0095] (Embodiment 3) Embodiment 3 will be described below with reference to Figures 10 and 11.

[0096] [3-1. Operation] During steady rotation, when the washing and spin-drying tub 4 is rotating at a stable speed, the torque current flowing through the motor 6 is positively correlated with the inertia of the washing and spin-drying tub 4. If the torque current during steady rotation is large, the inertia of the washing and spin-drying tub 4 is large, making it difficult for the rotation of the washing and spin-drying tub 4 to stop during brake control, and thus increasing the waiting time Tw during brake control. On the other hand, if the torque current during steady rotation is small, the inertia of the washing and spin-drying tub 4 is small, making it easier for the rotation of the washing and spin-drying tub 4 to stop during brake control, and thus decreasing the waiting time Tw during brake control.

[0097] As shown in Figure 10, the magnitude of the torque current is unstable during acceleration of the washing and spin-drying tub 4 and immediately after transitioning to steady rotation (for example, 3 to 10 seconds). Therefore, the control unit 22 calculates the average of the torque current values ​​over a predetermined time (for example, 1 second) during the period when the torque current is stable after transitioning to steady rotation (for example, 10 seconds or more after transitioning to steady rotation). This makes it possible to obtain a more accurate torque current value during steady rotation.

[0098] As shown in Figure 11, if the average torque current obtained above is X2 and the waiting time Tw is Y2, then Y2 can be set as a function of X2, given by Y2 = A2 × X2^2 + B2 × X2 + C2 (where A2, B2, and C2 are parameters). By appropriately setting parameters A2, B2, and C2, even if the amount of fabric is not determined or the correct amount of fabric cannot be determined, the control unit 22 can adjust the waiting time Tw from the average torque current during steady rotation relative to the predetermined waiting time Tw, thereby reducing the difference between the estimated stop time and the actual stop time of the washing and spin-drying tub 4.

[0099] [3-2. Effects] As described above, in this embodiment, the control unit 22 may adjust the waiting time Tw according to the magnitude of the torque current of the motor 6 during constant-speed rotation of the washing and dewatering tub 4.

[0100] This allows the waiting time Tw to be set from the torque current during steady rotation, even when the amount of fabric cannot be obtained, and the estimated time when the washing and spinning tub 4 stopped, and the actual washing and spinning The difference in time between when tank 4 stops and when it stops can be reduced.

[0101] (Embodiment 4) Embodiment 4 will be described below with reference to Figures 12 and 13.

[0102] [4-1. Operation] The torque current flowing through the motor 6 during acceleration of the washing and spin-drying tub 4 is positively correlated with the inertia of the washing and spin-drying tub 4. When the torque current during acceleration is large, the inertia of the washing and spin-drying tub 4 is large, making it difficult for the rotation of the washing and spin-drying tub 4 to stop during brake control, and thus increasing the waiting time Tw during brake control. On the other hand, when the torque current during acceleration is small, the inertia of the washing and spin-drying tub 4 is small, making it easier for the rotation of the washing and spin-drying tub 4 to stop during brake control, and thus decreasing the waiting time Tw during brake control.

[0103] As shown in Figure 12, during acceleration of the washing and spin-drying tub 4, there are rotational speeds (e.g., 50-150 r / min, 200-300 r / min, 450-550 r / min) in which the washing machine 1 is prone to vibration. In this rotational speed range, the actual rotational speed of the washing and spin-drying tub 4 and the torque current flowing through the motor 6 tend to fluctuate. Therefore, the control unit 22 calculates the average value of the torque current over a predetermined time (e.g., 0.5 seconds) in rotational speed ranges other than the vibration-prone range, where the torque current is relatively stable.

[0104] As shown in Figure 13, if the average torque current obtained above is X3 and the waiting time Tw is Y3, then Y3 can be set as a function of X3, where Y3 = A3 × X3^2 + B3 × X3 + C3 (A3, B3, and C3 are parameters). By appropriately setting parameters A3, B3, and C3, even if the amount of fabric is not determined or the correct amount of fabric cannot be determined, the control unit 22 can adjust the waiting time Tw from the average torque current during acceleration relative to the predetermined waiting time Tw, thereby reducing the difference between the estimated stop time and the actual stop time of the washing and spin-drying tub 4.

[0105] [4-2. Effects] As described above, in this embodiment, the control unit 22 may adjust the waiting time Tw according to the magnitude of the torque current of the motor 6 during acceleration of the washing and dewatering tub 4.

[0106] This allows for a reduction in the difference between the estimated time when the washing and spin-drying tub 4 stops and the actual time when the washing and spin-drying tub 4 stops, by setting a waiting time Tw from the torque current during acceleration, even when the amount of fabric cannot be obtained.

[0107] (Embodiment 5) Embodiment 4 will be described below with reference to Figures 14 and 15.

[0108] [5-1. Operation] Within the estimated rotational speed range of the washing and spin-drying tub 4, the deceleration time—the time required for the washing and spin-drying tub 4 to slow down from one rotational speed to another during brake control—is positively correlated with the inertia of the washing and spin-drying tub 4. A longer deceleration time indicates a larger inertia of the washing and spin-drying tub 4, making it more difficult for the tub 4 to stop rotating during brake control, thus increasing the waiting time Tw during brake control. Conversely, a shorter deceleration time indicates a smaller inertia of the washing and spin-drying tub 4, making it easier for the tub 4 to stop rotating during brake control, thus shortening the waiting time Tw during brake control.

[0109] As shown in Figure 14, during the deceleration of the washing and spin-drying tub 4, there is a rotational speed range (e.g., 50-150 r / min) in which the washing machine 1 is prone to vibration. In this configuration, the actual rotational speed of the washing and dehydrating tub 4 and the torque current flowing through the motor 6 are prone to fluctuations. Furthermore, in sensorless control, the control unit 22 can estimate the rotational speed of the washing and dehydrating tub 4 from the magnitude of the phase current in the motor 6 when the rotational speed of the washing and dehydrating tub 4 is high, but it cannot estimate the rotational speed of the washing and dehydrating tub 4 when the rotational speed of the washing and dehydrating tub 4 is low. If the control unit 22 sets the estimated lower limit rotational speed (e.g., 30 r / min) for the washing and dehydrating tub 4 that it can estimate, the control unit 22 avoids rotational speeds that are prone to vibration (e.g., 50-150 r / min) and rotational speeds lower than the estimated lower limit rotational speed (e.g., 30 r / min), and measures the deceleration time from a rotational speed (e.g., 35-45 r / min) where fluctuations in the estimated speed due to disturbances such as vibration and deterioration of estimated rotational speed accuracy are small. This allows for obtaining a more accurate deceleration time.

[0110] As shown in Figure 15, if the deceleration time obtained above is X4 and the waiting time Tw is Y4, then Y4 can be set as a function of X4, where Y4 = A4 × X4^2 + B4 × X4 + C4 (A4, B4, and C4 are parameters). By appropriately setting parameters A4, B4, and C4, even if the amount of fabric is not determined or the correct amount of fabric cannot be determined, the control unit 22 can adjust the waiting time Tw from the deceleration time relative to the default waiting time Tw, thereby reducing the difference between the estimated stop time and the actual stop time of the washing and spin-drying tub 4.

[0111] [5-2. Effects] As described above, in this embodiment, the control unit 22 may adjust the waiting time Tw according to the length of the deceleration time during the deceleration of the washing and dewatering tub 4.

[0112] This allows for a reduction in the difference between the estimated time when the washing and spin-drying tub 4 stops and the actual time when the washing and spin-drying tub 4 stops, by setting a waiting time Tw from the deceleration time during deceleration, even when the amount of fabric cannot be obtained.

[0113] (Other embodiments) As described above, Embodiments 1 to 5 have been explained as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited thereto and can be applied to embodiments that have been modified, replaced, added, or omitted. Furthermore, it is possible to create new embodiments by combining the components described in Embodiments 1 to 5 above.

[0114] Therefore, other embodiments are illustrated below.

[0115] In this embodiment, as an example of a washing machine, a washing machine 1 that uses a sensorless control method without a position detection sensor to detect the rotation speed of the washing and spin-drying tub was described. The washing machine is not limited to the washing machine 1 that uses a sensorless control method, as it can control the rotation of the washing and spin-drying tub. The washing machine may be controlled by vector control, which controls the current vector using a motor with a rotation sensor, or by voltage control, which controls the speed by adjusting the voltage and modulation degree. In this case, the estimated rotation speed in the embodiment is replaced with the rotation speed detected by the rotation sensor, and the estimated lower limit rotation speed is replaced with the detected lower limit rotation speed.

[0116] In this embodiment, as an example of a drum rotation process, a drum rotation process in which the drum is rotated while water is present in the washing and spin-drying drum was described. The drum rotation process may be performed while supplying water, or while draining water.

[0117] (Note) Based on the above description of embodiments, the following technologies are disclosed.

[0118] The washing machine in the first embodiment comprises a housing, an outer tub provided within the housing to store water, a washing and dewatering tub provided within the outer tub for holding laundry, an electric motor that serves as a driving source for the rotation of the washing and dewatering tub, and a control unit that controls the rotation of the electric motor and controls the operation including the first step, wherein, during the deceleration of the washing and dewatering tub in the first step, the control unit enables post-stop operation after a first time determined according to the amount of laundry has elapsed, after the magnitude of the phase current of the electric motor or the estimated rotational speed of the washing and dewatering tub falls below a predetermined value.

[0119] In the second embodiment of the washing machine, as in the washing machine of the first embodiment, the control unit sets the first time to be longer the larger the amount of fabric.

[0120] In a third embodiment of the washing machine, in the washing machine of the first or second embodiment, the control unit sets the first time when the first step is performed with water in the outer tub to be longer than the first time when the first step is performed with the water in the outer tub drained.

[0121] The washing machine in the fourth embodiment further comprises, in addition to the washing machine in any one of the first to third embodiments, a lid that can open and close to cover an opening formed in the housing, and a lid locking means for locking the lid in a closed state, wherein when the control unit receives an instruction to temporarily suspend operation, after 1 hour has elapsed since the magnitude of the phase current or the estimated rotation speed fell below a predetermined value, it performs a post-stop operation by releasing the lock on the lid using the lid locking means.

[0122] In the fifth embodiment, as a washing machine in any one of the first to fourth embodiments, the control unit can set the first time when it receives an instruction to temporarily suspend operation to be shorter than the first time when it does not receive an instruction to temporarily suspend operation.

[0123] As a washing machine in the sixth embodiment, in a washing machine in any one of the first to fifth embodiments, if the control unit has not received an instruction to temporarily suspend operation, it restarts the motor as a post-stop operation when 1 hour has elapsed after the magnitude of the phase current or the estimated rotation speed falls below a predetermined value, enabling the rotation of the washing and spin-drying tub.

[0124] The washing machine in the seventh embodiment further comprises, in the washing machine of any one of the first to sixth embodiments, an agitator rotatably mounted inside the washing and dewatering tub, and a clutch for switching the output of the electric motor to the rotation of the agitator or the washing and dewatering tub, wherein, if the control unit has not received an instruction to temporarily suspend operation, it enables the switching of the clutch as a post-stop operation after 1 hour has elapsed since the magnitude of the phase current or the estimated rotational speed fell below a predetermined value.

[0125] In the eighth aspect of the washing machine, in any one of the first to seventh aspects, the control unit adjusts the first time according to the magnitude of the torque current of the electric motor during constant rotation of the washing and spinning tub.

[0126] In the ninth embodiment, as a washing machine in any one of the first to eighth embodiments, the control unit adjusts the first time according to the magnitude of the torque current of the electric motor during acceleration of the washing and spin-drying tub.

[0127] In the washing machine according to the tenth embodiment, in the washing machine according to any one of the first to ninth embodiments, the control unit adjusts the first time according to the length of the deceleration time during the deceleration of the washing and spinning tub. [Industrial applicability]

[0128] This disclosure is applicable to washing machines. [Explanation of Symbols]

[0129] 1. Washing machine 2. Washing machine outer frame (casing) 2a Inlet 3. Water receiving tank (outer tank) 4. Washing and spin-drying tub 4a Water passage hole 5. Pulsator (agitator blade) 6. Motor (electric motor) 7 belts 8. Means of transmission 9 Control device 10 Operation display section 10a Input setting means 10b Display means 11 Lid 14 Magnets 15 Magnetic element 16. Lid opening / closing detection means 17. Lock section 18 lock pins 19 Lid locking mechanism 20 Water supply valve 21 Drain valve 21a Geared motor 22 Control Unit 23 Switching means 23a Switching control means 24 Power circuit 55, 56, 57, 58, 59, 60 Switching elements 61 Drive Circuit 66, 67, 68 Shunt resistors 70 Amplifier Circuit 71 Current detection circuit 100 First Coordinate Transformer 101 Current Error Amplifier 102 Error Subtractor 103 Error Subtractor 104 Coordinate Transformer 105 Current Control Unit 107 Phase Error Detector 108 Speed ​​Calculator 110 Integrator 111 Speed ​​command means 112 Subtractors 113 Speed ​​Error Amplifier 115 Current Vector Setter 118 Switch 119 Switch

Claims

1. The casing and An outer tank is provided within the housing so as to be able to store water, A washing and dewatering tub for holding laundry is provided inside the outer tub, An electric motor that serves as the driving source for the rotation of the washing and spin-drying tub, A control unit that controls the rotation of the electric motor and controls the operation including the first step, Equipped with, The control unit, During the deceleration of the washing and dewatering tub in the first step, after the magnitude of the phase current of the motor or the estimated rotational speed of the washing and dewatering tub falls below a predetermined value, and after a first time has elapsed determined according to the amount of laundry, the post-stop operation can be performed. The first time is adjusted according to the length of the deceleration time during the deceleration of the washing and spin-drying tub. washing machine.

2. Housing and An outer tank is provided within the housing so as to be able to store water, A washing and dewatering tub for holding laundry is provided inside the outer tub, A lid that can be opened and closed to cover the input opening formed in the housing, A lid locking means for locking the lid in a closed position, An electric motor that serves as the driving source for the rotation of the washing and spin-drying tub, A control unit that controls the rotation of the electric motor and controls the operation including the first step, Equipped with, The control unit, During the deceleration of the washing and dewatering tub in the first step, after the magnitude of the phase current of the motor or the estimated rotational speed of the washing and dewatering tub falls below a predetermined value, and after a first time has elapsed determined according to the amount of laundry, the post-stop operation can be performed. When an instruction to temporarily suspend the operation is received, and the magnitude of the phase current or the estimated rotational speed falls below a predetermined value, the first time elapses, and as a post-stop operation, the lid locking means is used to release the lock on the lid. The first time period when an instruction to temporarily suspend the operation is received can be set to be shorter than the first time period when an instruction to temporarily suspend the operation is not received. washing machine.

3. Housing and An outer tank is provided within the housing so as to be able to store water, A washing and dewatering tub for holding laundry is provided inside the outer tub, An electric motor that serves as the driving source for the rotation of the washing and spin-drying tub, A control unit that controls the rotation of the electric motor and controls the operation including the first step, Equipped with, The control unit, During the deceleration of the washing and dewatering tub in the first step, after the magnitude of the phase current of the motor or the estimated rotational speed of the washing and dewatering tub falls below a predetermined value, and after a first time has elapsed determined according to the amount of laundry, the post-stop operation can be performed. The first time is adjusted according to the magnitude of the torque current of the electric motor during constant rotation of the washing and spin-drying tub. washing machine.

4. Housing and An outer tank is provided within the housing so as to be able to store water, A washing and dewatering tub for holding laundry is provided inside the outer tub, An electric motor that serves as the driving source for the rotation of the washing and spin-drying tub, A control unit that controls the rotation of the electric motor and controls the operation including the first step, Equipped with, The control unit, During the deceleration of the washing and dewatering tub in the first step, after the magnitude of the phase current of the motor or the estimated rotational speed of the washing and dewatering tub falls below a predetermined value, and after a first time has elapsed determined according to the amount of laundry, the post-stop operation can be performed. The first time is adjusted according to the magnitude of the torque current of the electric motor during acceleration of the washing and dewatering tub. washing machine.

5. The control unit sets the first time to be longer as the amount of fabric increases. A washing machine according to any one of claims 1 to 4.

6. The control unit sets the first time to be longer when the first step is performed with water inside the outer tank than when the first step is performed with the water drained from the outer tank. A washing machine according to any one of claims 1 to 4.

7. If the control unit has not received an instruction to temporarily suspend the operation, and the first time has elapsed since the magnitude of the phase current or the estimated rotation speed fell below a predetermined value, the control unit will restart the motor as a post-stop operation, enabling the rotation of the washing and dewatering tub to be performed. A washing machine according to any one of claims 1 to 4.

8. A rotatable agitator blade is provided inside the washing and dewatering tub, A clutch that switches the output of the electric motor to the rotation of the agitator blade, or the agitator blade and the washing / drying tub, Furthermore, If the control unit has not received an instruction to temporarily suspend the operation, the magnitude of the phase current... Alternatively, after the estimated rotational speed falls below a predetermined value and the first time has elapsed, the clutch switching can be performed as a post-stop operation. A washing machine according to any one of claims 1 to 4.

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