WO2019128733A1

WO2019128733A1 - Washing machine

Info

Publication number: WO2019128733A1
Application number: PCT/CN2018/121074
Authority: WO
Inventors: 间宫春夫
Original assignee: 青岛海尔洗衣机有限公司; Aqua株式会社
Priority date: 2017-12-26
Filing date: 2018-12-14
Publication date: 2019-07-04
Also published as: JP7164100B2; JP2019115389A

Abstract

A washing machine, which is capable of detecting clothing rotation state at low cost. The washing machine (1) comprises: a washing tub (4) that contains laundry (Q); a pulsator (5) that is configured within the washing tub (4); a water level detecting part (28) that detects the water level in the washing tub (4); and a microcomputer (21). After the microcomputer (21) opens a water supply valve (14) to supply water into the washing tub (4) to a set water level (f), the pulsator (5) intermittently rotates so as to carry out washing, and water flow is generated in the washing tub (4) by means of the rotation of the pulsator (5). The microcomputer obtains a water level reduction amount (△F) in the washing tub (4) on the basis of the difference during the cleaning process between the water level (fr) detected by the water level detecting part (28) during a period in which the rotation of the pulsator (5) is interrupted and the set water level (f). When the water level reduction amount (△F) is less than a first threshold (α), the microcomputer (21) weakens the intensity of the water flow.

Description

washing machine

Technical field

The present invention relates to a washing machine.

Background technique

The washing machine described in Patent Document 1 includes: an outer tub that can store water; an inner tub housed in the outer tub; a stirring wing disposed in the inner tub; a driving motor that rotates the stirring blade; and a water level that detects a water level in the outer tub a sensor; and a pulse encoder that extracts a rotation pulse of the drive motor. After the water is supplied to the determined water level in the outer tub, the stirring wing is rotated by the drive motor. Thereby, a water flow is generated in the inner tub, and the laundry in the inner tub is washed by the water flow. In the cleaning process, the rotation state of the cloth is detected in consideration of the "splashing" phenomenon in which the water in the inner tub splashes to the outside due to the water flow. Specifically, the number of the inertial rotation pulses when the drive motor is turned off is extracted by the pulse encoder, and if the number of the inertia rotation pulses is larger than the predetermined value, it is determined that the cloth rotation is too good, that is, it is determined that the water splash is likely to occur.

In the case where a relatively expensive pulse encoder is used to detect the rotation state of the cloth like the washing machine described in Patent Document 1, it is difficult to reduce the cost.

Prior art literature

Patent literature

Patent Document 1: Japanese Patent No. 3015638

Summary of the invention

Problems to be solved by the invention

The present invention has been made in such a background, and an object thereof is to provide a washing machine capable of detecting a cloth rotation state at low cost.

Solution to solve the problem

The washing machine of the present invention includes: a washing tub for accommodating laundry; a water supply portion that supplies water into the washing tub; a rotating member disposed in the washing tub; and a water flow generating portion that passes the washing tub to the washing tub After the internal water supply to the set water level, the rotating member is intermittently rotated for washing, and a water flow is generated in the washing tub by the rotation of the rotating member; a water level detecting portion detects a water level in the washing tub; The acquisition unit acquires a water level decrease amount in the washing tub based on a difference between a water level detected during a period in which the rotation of the rotating member is interrupted by the water level detecting unit during the cleaning process, and the acquisition When the amount of water level reduction obtained by the part is less than the first threshold value, the water flow generating unit reduces the intensity of the water flow.

Further, the present invention is characterized in that, when the amount of water level decrease obtained by the acquisition unit is larger than a second threshold value larger than the first threshold value, the water flow generation unit enhances the intensity of the water flow.

Further, according to the present invention, the acquisition unit acquires the water level decrease amount based on a difference between a water level detected by the water level detecting unit after a predetermined period of time and the set water level in the cleaning process.

Effect of the invention

According to the present invention, in the washing machine, after the water is supplied into the washing tub to the set water level, the rotating member in the washing tub intermittently rotates. The laundry in the washing tub is washed by the flow of water generated by the rotation of the rotating member. The water level decrease amount of the difference between the water level in the washing tub and the set water level detected by the water level detecting unit during the cleaning process during the cleaning process is an index of the cloth rotation state. When the amount of water level reduction is less than the first threshold value, the amount of laundry is small with respect to the current amount of water, so that the cloth is rotated too well, that is, the activity of the laundry is too active, so that splashing water is likely to occur. Therefore, the intensity of the water flow is weakened. In this way, by using the conventional water level detecting unit, the rotation state of the cloth can be detected at low cost, and the occurrence of splashing water can be suppressed.

Further, according to the present invention, in the case where the amount of water level decrease is larger than the second threshold value which is larger than the first threshold value, the laundry is excessive with respect to the current amount of water, so that the cloth rotation is poor, that is, the activity of the laundry is slow, so that it is difficult to pass. The water stream effectively washes the laundry. In this case, in order to increase the strength of the water flow in order to make the cloth rotation better, it is possible to efficiently wash the laundry by the intensity-enhanced water flow.

Further, according to the present invention, it is possible to obtain the water level reduction amount with a small deviation based on the difference between the water level which has been stabilized for a predetermined period of time in the cleaning process and the set water level, and therefore the cloth rotation state can be accurately detected.

DRAWINGS

Fig. 1 is a schematic longitudinal cross-sectional view showing a washing machine in accordance with an embodiment of the present invention.

Fig. 2 is a block diagram showing an electrical configuration of a washing machine.

Fig. 3 is a flow chart showing a part of the processing in the washing process performed in the washing machine.

Fig. 4 is a flow chart showing the remaining processing in the cleaning process.

FIG. 5 is a flowchart showing details of processing in the middle of the cleaning process.

Fig. 6 is a timing chart showing the state of the motor and the water level in the washing tub during the washing process.

Description of the reference numerals

1: washing machine; 4: washing tub; 5: pulsator; 14: water supply valve; 21: microcomputer; 28: water level detecting unit; f: setting water level; fr: water level; Δf: water level reducing amount; Q: washing ; α: first threshold; β: second threshold.

Detailed ways

Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. Fig. 1 is a schematic longitudinal cross-sectional view of a washing machine 1 according to an embodiment of the present invention. The vertical direction in FIG. 1 is referred to as the vertical direction Z of the washing machine 1, and in the vertical direction Z, the upper side is referred to as the upper side Z1, and the lower side is referred to as the lower side Z2. The washing machine 1 includes a casing 2, an outer tub, a washing tub 4, a pulsator 5 as an example of a rotating member, a motor 6, and a transmission mechanism 7.

The case 2 is made of, for example, metal, and is formed in a box shape. An opening 2B that allows the inside and the outside of the casing 2 to communicate with each other is formed on the upper surface 2A of the casing 2. A door 10 that opens and closes the opening 2B is provided on the upper surface 2A. A display operation portion 11 composed of a liquid crystal operation panel or the like is provided around the opening 2B of the upper surface 2A. The user of the washing machine 1 selects the operating conditions of the washing operation performed by the washing machine 1 by operating the display operation unit 11, or instructs the washing machine 1 to start or stop the washing operation. The display operation unit 11 displays information provided to the user.

The outer tub 3 is made of, for example, a resin, and is formed into a bottomed cylindrical shape. The outer tub 3 has a substantially cylindrical circumferential wall 3A disposed in the up-and-down direction Z, a bottom wall 3B that blocks the hollow portion of the circumferential wall 3A from the lower side Z2, and an annular annular wall 3C that surrounds the circumferential wall 3A. The end edge of the upper side Z1 side is hem and protrudes toward the center side of the circumferential wall 3A. Inside the annular wall 3C, an inlet and outlet 3D that communicates from the upper side Z1 is formed in a hollow portion of the circumferential wall 3A. The doorway 3D faces the opening 2B of the casing 2 from the lower side Z2, and is in a communicating state. A door 12 that opens and closes the entrance and exit 3D is provided in the annular wall 3C. The bottom wall 3B is formed in a disk shape extending substantially horizontally, and a through hole 3E penetrating the bottom wall 3B is formed at a center position of the bottom wall 3B.

In the annular wall 3C of the outer tub 3, a water supply path 13 connected to the tap of the tap water is connected from the upper side Z1. A water supply valve 14 as an example of a water supply unit is provided in the middle of the water supply path 13. A drain passage 15 is connected to the bottom wall 3B of the outer tub 3 from the lower side Z2. A drain valve 16 is provided in the middle of the drain passage 15. When the water supply valve 14 is opened in a state where the drain valve 16 is closed, water can be supplied to the outer tub 3 by supplying water from the water supply path 13 to the outside of the tub 3. When the water supply valve 14 is closed, the water supply is stopped. When the drain valve 16 is opened, the water in the outer tub 3 is discharged from the drain passage 15 to the outside of the machine.

The washing tub 4 is made of, for example, metal, and has a bottomed cylindrical shape that is smaller than the outer tub 3, and can accommodate the laundry Q inside. The washing tub 4 is housed coaxially in the outer tub 3. The washing tub 4 in a state of being housed in the outer tub 3 is rotatable about an axis J which is a central axis thereof and extends in the vertical direction Z. The washing tub 4 has a substantially cylindrical circumferential wall 4A disposed in the up-and-down direction Z, and a bottom wall 4B that blocks the hollow portion of the circumferential wall 4A from the lower side Z2.

The inner circumferential surface of the circumferential wall 4A is the inner circumferential surface of the washing tub 4. The upper end portion of the inner circumferential surface of the circumferential wall 4A is an inlet and outlet 4C that exposes the hollow portion of the circumferential wall 4A to the upper side Z1. The entrance and exit 4C is opposed to the entrance and exit 3D of the outer tub 3 from the lower side Z2, and is in a communicating state. The user takes the laundry Q from the upper side Z1 to the washing tub 4 via the open opening 2B, the entrance 3D, and the entrance 4C.

A plurality of through holes 4D are formed in the circumferential wall 4A and the bottom wall 4B of the washing tub 4, and water in the outer tub 3 passes between the outer tub 3 and the washing tub 4 through the through holes 4D, and can also be stored in the washing tub 4. Therefore, the water level in the outer tub 3 coincides with the water level in the washing tub 4.

The bottom wall 4B of the washing tub 4 is formed in a disk shape extending substantially parallel to the upper side Z1 of the bottom wall 3B of the outer tub 3, and is formed at a center of the bottom wall 4B at the center of the axis J. The through hole 4E of the wall 4B. A tubular support shaft 17 is provided on the bottom wall 4B, surrounding the through hole 4E and extending along the axis J to the lower side Z2. The support shaft 17 is inserted into the through hole 3E of the bottom wall 3B of the outer tub 3, and the lower end portion of the support shaft 17 is located on the lower side Z2 of the bottom wall 3B.

The pulsator 5 is formed in a disk shape centered on the axis J, and is disposed concentrically with the washing tub 4 along the bottom wall 4B in the washing tub 4. In the pulsator 5, a plurality of blades 5A radially arranged are provided on the upper surface of the inlet and outlet 4C facing the washing tub 4. The pulsator 5 is provided with a rotating shaft 18 extending from its center along the axis J to the lower side Z2. The rotating shaft 18 is inserted into the hollow portion of the support shaft 17, and the lower end portion of the rotating shaft 18 is located on the lower side Z2 of the bottom wall 3B of the outer tub 3.

The motor 6 is an electric motor such as a variable frequency motor. The motor 6 is disposed in the casing 2 on the lower side Z2 of the outer tub 3. The motor 6 has an output shaft 19 that rotates about the axis J, and outputs the generated driving force from the output shaft 19. The transmission mechanism 7 is interposed between the lower end portion of each of the support shaft 17 and the rotary shaft 18 and the upper end portion of the output shaft 19 that protrudes from the motor 6 to the upper side Z1. The transmission mechanism 7 selectively transmits the driving force output from the output shaft 19 of the motor 6 to one or both of the support shaft 17 and the rotation shaft 18. A known mechanism is used as the transmission mechanism 7. When the driving force from the motor 6 is transmitted to the support shaft 17 and the rotary shaft 18, the washing tub 4 and the pulsator 5 receive the driving force of the motor 6 to rotate about the axis J.

FIG. 2 is a block diagram showing an electrical configuration of the washing machine 1. The washing machine 1 includes a water supply unit, a water flow generation unit, and a microcomputer 21 as an example of an acquisition unit. The microcomputer 21 includes, for example, a memory 22 such as a CPU 22, a ROM or a RAM, and a timer 24 for counting, and is built in the casing 2 (see Fig. 1).

The motor 6, the transmission mechanism 7, the water supply valve 14, and the drain valve 16 are electrically connected to the microcomputer 21 via, for example, the drive circuit 25, and the display operation unit 11 described above is also electrically connected to the microcomputer 21. The microcomputer 21 turns on the motor 6 to drive it, or turns off the motor 6 to stop it. The microcomputer 21 can also control the direction of rotation of the motor 6. Thereby, the motor 6 can be rotated forward or reversed. The microcomputer 21 controls the transmission mechanism 7 to switch the transmission target of the driving force of the motor 6 to one or both of the support shaft 17 and the rotation shaft 18. The microcomputer 21 controls opening and closing of the water supply valve 14 and the drain valve 16. When the user operates the display operation unit 11 to select an operation condition or the like, the microcomputer 21 receives the selection. The microcomputer 21 controls the display content of the display operation unit 11.

The washing machine 1 further includes a buzzer 26 electrically connected to the microcomputer 21, a rotational speed reading device 27, and a water level detecting portion 28. The microcomputer 21 notifies the user of the start or end of the washing operation by causing the buzzer 26 to emit a predetermined sound.

The rotational speed reading device 27 is a reading device that reads the rotational speed of the motor 6, and strictly reads the rotational speed of the output shaft 19 of the motor 6, and is constituted, for example, by a Hall IC. The rotational speed read by the rotational speed reading device 27 is input to the microcomputer 21 in real time. The microcomputer 21 controls the duty ratio of the voltage applied to the motor 6 based on the input rotational speed, thereby controlling the motor 6 to rotate at a desired rotational speed. In addition, the rotation speed of each of the washing tub 4 and the pulsator 5 may be the same as the rotation speed of the motor 6, or may be a value obtained by multiplying a predetermined constant such as a reduction ratio in the transmission mechanism 7 by the rotation speed of the motor 6. .

The water level detecting unit 28 is a water level sensor that detects the water level in the outer tub 3, that is, the water level in the washing tub 4. In the present embodiment, the pressure level is detected based on the pressure in the outer tub 3 to detect the water level in the washing tub 4. sensor. Specifically, the water level detecting unit 28 is connected to an air trap 29 that is a space that communicates with the lower portion of the internal space of the outer tub 3 via the ventilation hose 30 (see FIG. 1 ). The hole 29 generates a pressure corresponding to the water level in the washing tub 4, and the pressure is transmitted to the water level detecting unit 28 via the vent hose 30, and the diaphragm (not shown) of the water level detecting unit 28 is vibrated. The frequency of the vibrating diaphragm or the frequency of an oscillating circuit (not shown) that is interlocked with the diaphragm indicates the water level in the washing tub 4. That is, the water level detecting unit 28 converts the water level in the washing tub 4 into a frequency and outputs it. When the water level in the washing tub 4 rises, the frequency output from the water level detecting portion 28 decreases, and when the water level in the washing tub 4 decreases, the frequency output from the water level detecting portion 28 rises. It should be noted that other known configurations can be used as the water level detecting unit 28.

The microcomputer 21 performs a washing operation by controlling the operations of the motor 6, the transmission mechanism 7, the water supply valve 14, and the drain valve 16. The washing operation has a washing process of washing the laundry Q, a rinsing process of rinsing the laundry Q after the washing process, and a dehydrating process of rotating the washing tub 4 to dehydrate the laundry Q after the rinsing process. It should be noted that the washing machine 1 may also be a washing and drying machine that performs a drying process of drying the laundry Q after the dehydration process.

When the user puts the laundry Q into the washing tub 4 and instructs to start the washing operation, the microcomputer 21 starts the washing process. It should be noted that the user may also put the detergent into the washing tub 4 before or after the laundry Q is put in. Referring to the flowchart of FIG. 3, first, the microcomputer 21 confirms whether or not the water level in the washing tub 4 during the washing process has been manually set in accordance with the operation of the display operation portion 11 by the user (step S1). If the water level is not manually set (NO in step S1), the microcomputer 21 detects the amount of the laundry Q in the washing tub 4, that is, the load amount (step S2). As an example of the load amount detection, the microcomputer 21 detects the amount of load based on the deviation of the number of revolutions of the motor 6 when the washing tub 4 is stably rotated at a low speed. Then, the microcomputer 21 determines the water level of the water stored in the washing tub 4 after the water supply is subsequently performed based on the amount of load just detected (step S3). The relationship between the water level and the load amount is obtained in advance by experiments or the like and stored in the memory 23.

The water level manually set by the user or the water level determined in step S3 is referred to as the set water level f. The microcomputer 21 determines the initial value of the set value of the intensity of the water flow generated in the washing tub 4 by the rotation of the pulsator 5 in the current washing process based on the set water level f (step S4). A plurality of levels including the lower limit value and the upper limit value are set in the set value, and a value of any level can be used as the initial value. The relationship between the set value and the set water level f is obtained in advance by an experiment or the like and stored in the memory 23. The set value is specifically related to the rotational speed of the motor 6, that is, the energization time of the motor 6. When the set value is raised to the upper limit side, the energization time becomes longer and the rotational speed is the rotational speed of the pulsator 5, so the water flow The intensity segmentation is enhanced.

Next, the microcomputer 21 opens the water supply valve 14 to start supplying water into the washing tub 4 (step S5). Since the drain valve 16 is in the closed state, the water level in the washing tub 4 rises. When the water level in the washing tub 4 reaches the set water level f, the microcomputer 21 closes the water supply valve 14 to stop supplying water to the washing tub 4, and starts washing the laundry Q (step S6). Specifically, the microcomputer 21 rotates the pulsator 5 by the motor 6 in a state where the washing tub 4 is stationary. Thereby, a water flow of intensity corresponding to the above initial value is generated in the washing tub 4. The laundry Q in the washing tub 4 is stirred by the rotating pulsator 5 or the water flow. Therefore, the dirt is removed from the laundry Q. That is, the laundry Q is cleaned. In the case where the detergent is put into the washing tub 4, the dirt of the laundry Q is decomposed by the detergent.

The microcomputer 21 measures the elapsed time from the start of the stirring in step S6 by the timer 24. When the cleaning time set for this cleaning process has elapsed (YES in step S7), the microcomputer 21 stops the rotation of the pulsator 5 by the motor 6, and opens the drain valve 16 to discharge the washing tub 4 ( Step S8). Thereby, the cleaning process ends.

The period until the cleaning time has elapsed (NO in step S7), the microcomputer 21 performs the water level decrease amount determining process shown in Fig. 4 (step S11). The water level reduction amount determining process will be described with reference to the flowchart of Fig. 5 and the timing chart of Fig. 6. In the timing chart of FIG. 6, the horizontal axis represents the elapsed time, and the vertical axis represents the on/off state of the motor 6 and the frequency at which the water level as the water level in the washing tub 4 is output by the detecting unit 28. The unit of elapsed time is, for example, seconds, and the unit of frequency is, for example, KHZ. It should be noted that, as described above, when the actual water level in the washing tub 4 is lowered, the frequency corresponding to the water level is increased.

In the cleaning time, the microcomputer 21 repeats the agitation cycle in which the forward rotation and the reverse rotation of the motor 6 are alternately repeated a plurality of times. One agitation cycle lasts, for example, for 20 seconds. In each stirring cycle, the pulsator 5 is rotated forward in the same direction as the output shaft 19 of the motor 6 in accordance with the normal rotation of the motor 6, and the pulsator 5 is reversed in the same direction as the output shaft 19 in accordance with the reversal of the motor 6. It should be noted that the pulsator 5 may be continuously rotated in one direction by rotating the motor 6 only in the forward or reverse direction in each stirring cycle. The microcomputer 21 turns off the motor 6 during the pause cycle between the respective stirring cycles, so that the rotation of the pulsator 5 is stopped. Therefore, the microcomputer 21 intermittently rotates the pulsator 5 by alternately repeating the agitation cycle and the pause cycle in the washing time. The above-described water flow is generated in the washing tub 4 by the rotation of the pulsator 5 in the stirring cycle to agitate the laundry Q.

In the cleaning process, when 20 seconds have elapsed from the start of the stirring cycle, that is, from the start of the stirring of the laundry Q (YES in step S111), the microcomputer 21 stops the stirring of the laundry Q by stopping the rotation of the pulsator 5, that is, The stirring cycle is ended (step S112). Thus, the pause loop begins. The microcomputer 21 increments the number N of detections set in advance in the memory 23 by 1 (+1) (step S113). Since the number N of detections before the start of the cleaning is 0, the number N of detections at the end of the first stirring cycle immediately after the start of the cleaning is 1. In this case (YES in step S114), the microcomputer 21 repeats the processing from step S111.

Since the number N of detections at the end of the second-time stirring cycle is larger than 1, in this case (NO in step S114), the microcomputer 21 confirms whether or not the agitation stop in step S112 is the start of the pause cycle. For example, a predetermined time of 4 seconds (step S115). When the predetermined time has elapsed (YES in step S115), the microcomputer 21 measures the current water level fr in the washing tub 4 by the water level detecting unit 28 (step S116). Strictly speaking, since the water level detecting unit 28 always detects the water level in the washing tub 4, the microcomputer 21 acquires the detection result of the water level detecting unit 28 at the time when the predetermined time has elapsed as the water level fr. The water level in the washing tub 4 is lowered by the water absorption of the laundry Q, so the water level fr is lower than the initial set water level f. The microcomputer 21 calculates the absolute value of the difference between the set water level f and the water level fr, and takes the absolute value as the water level decrease amount Δf in the washing tub 4 (step S117).

The microcomputer 21 repeats the processing from steps S111 to S117 until the number N of detections is, for example, four times a predetermined number of times. Thus, here, the microcomputer 21 calculates the water level decrease amount Δf once in each of the second to fourth pause cycles, and calculates the total amount three times (step S117). When the number of detections N reaches the predetermined number of times (NO in step S118), the microcomputer 21 determines the final value of the water level decrease amount Δf (step S119). This final value is referred to as the water level reduction amount ΔF. The water level decrease amount ΔF itself may be the water level decrease amount Δf calculated at any one of the second to fourth times. Alternatively, the water level decrease amount ΔF may be an integrated value obtained by summing the plurality of water level decrease amounts Δf calculated this time, or may be an average value obtained by dividing the cumulative value by the number of calculations of the water level decrease amount Δf. When the number N of detections is four, the water level decrease amount ΔF is determined in the fourth pause cycle (see FIG. 6). When the water level decrease amount ΔF is determined, the water level decrease amount determination process ends. Further, based on the determination of the water level decrease amount ΔF, the microcomputer 21 resets the number of detections N to zero.

Returning to Fig. 4, the microcomputer 21 confirms whether or not the determined water level decrease amount ΔF is lower than the first threshold value α (step S12). The first threshold value α is a value that is determined in advance by an experiment or the like in order to determine whether or not the water level decrease amount ΔF is smaller than the assumed amount due to the water absorption of the laundry Q, and is stored in the memory 23. When the water level decrease amount ΔF is smaller than the first threshold value α (YES in step S12), the microcomputer 21 confirms the current water level fr measured by the water level detecting unit 28 (step S13).

In the case where the water level fr is a high water level near the upper limit water level when the maximum water storage in the washing tub 4 is reached or a middle water level when the water is stored in the washing tub 4 to about half (YES in step S13), if the current water flow is maintained, As a result, there is a high possibility that the water in the washing tub 4 splashes from the inlet and outlet 4C to the outside. Therefore, if the current set value of the intensity of the water flow is not the lower limit value (NO in step S14), the microcomputer 21 lowers the set value by one step (step S15). Thus, when the next stirring cycle is started, the agitation of the laundry Q is restarted by the water flow whose strength is weakened by one stage.

On the other hand, when the water level fr is lower than the middle water level (NO in step S13), the possibility of occurrence of splashing water is low, and therefore the microcomputer 21 maintains the set value of the water flow as it is. Further, although the water level is the high water level or the middle water level (YES in step S13), if the current water flow setting value is the lower limit value (YES in step S14), since the set value cannot be further degraded, The microcomputer 21 maintains the set value of the water flow as it is. When the next agitation cycle is started while the set value of the water flow is maintained as it is, the agitation of the laundry Q is restarted by the water flow of the same strength as the previous agitation cycle.

When the water level decrease amount ΔF is equal to or greater than the first threshold value α (NO in step S12), the microcomputer 21 confirms whether or not the water level decrease amount ΔF exceeds the second threshold value β (step S16). The second threshold value β is a value obtained in advance by an experiment or the like in order to determine whether or not the water level decrease amount ΔF is larger than the assumed amount due to the water absorption of the laundry Q, and is stored in the memory 23. The second threshold β is larger than the first threshold α. When the water level decrease amount ΔF exceeds the second threshold value β (YES in step S16), the amount of laundry Q is large with respect to the current amount of water, and there is a possibility that the laundry Q is sluggish, that is, the cloth rotation difference is caused. In this case, the microcomputer 21 confirms the current set value of the water flow (step S17). If the current water flow is not the upper limit value (NO in step S17), the set value is incremented by one step (step S18). Thus, when the next agitation cycle begins, the agitation of the laundry Q is restarted by the intensity-enhanced first-order water flow.

On the other hand, when the water level decrease amount ΔF is equal to or less than the second threshold value β (NO in step S16), the cloth rotation state is appropriate (refer to the water level shown by the thick solid line in FIG. 6), and the microcomputer 21 will The set value of the water flow maintains the status quo. Further, although the water level decrease amount ΔF exceeds the second threshold value β (YES in step S16), if the current water flow setting value is the upper limit value (YES in step S17), the set value cannot be upgraded again. Therefore, the microcomputer 21 maintains the set value of the water flow as it is. When the next agitation cycle is started while the set value of the water flow is maintained as it is, the agitation of the laundry Q is restarted by the water flow of the same strength as the previous agitation cycle.

When the rinsing process after the washing process is started, the microcomputer 21, after supplying water to the set water level in the washing tub 4, rotates the pulsator 5 by the motor 6 in a state where the washing tub 4 is stationary. Thereby, a water flow is generated in the washing tub 4, and the laundry Q in the washing tub 4 is rinsed by being stirred by the rotating pulsator 5 or the water flow. When the rinsing time set for this rinsing process has elapsed, the microcomputer 21 stops the rotation of the pulsator 5 by the motor 6 to perform drainage of the washing tub 4. Thereby, the rinsing process ends. The set water level during the rinsing process can be the same as the set water level f during the cleaning process. Further, during the rinsing process, the water flow adjustment processing of steps S11 to S18 in the cleaning process can be performed until the rinsing time elapses. The rinsing process can also be carried out multiple times.

In the dehydration process after the rinsing process, the microcomputer 21 rotates the washing tub 4 at a high speed in a state where the drain valve 16 is opened. The laundry in the washing tub 4 is dehydrated by the centrifugal force generated by the high-speed rotation. The water oozing out from the laundry by dehydration is discharged from the drainage path 15 to the outside of the machine. It should be noted that the dehydration process can also be carried out as an intermediate dehydration process different from the final dehydration process performed at the end of the washing operation, respectively after the washing process and the rinsing process.

As described above, in the washing machine 1, the microcomputer 21 obtains the washing tub 4 based on the difference between the water level fr detected in the pause cycle and the set water level f during the washing process during the washing process. The amount of water level reduction within the ΔF. The water level reduction amount ΔF is an index of the cloth rotation state, that is, the activity state of the laundry Q accompanying the water flow. In the case where the water level decrease amount ΔF is smaller than the first threshold value α, the laundry Q is small with respect to the current water amount, so that the cloth rotation is too good, that is, the activity of the laundry Q is too active, so that splashing water is likely to occur (refer to The water level shown by a thick one-dot chain line in Fig. 6). When the water level decrease amount ΔF is smaller than the first threshold value α (YES in step S12), the microcomputer 21 degrades the set value of the water flow (step S15), and weakens the water flow intensity after the pulsator 5 restarts rotation.

On the contrary, in the case where the water level decrease amount ΔF is larger than the second threshold value β (YES in step S16), the laundry Q is excessive with respect to the current amount of water, so that the cloth rotation is poor, that is, the activity of the laundry Q is sluggish. It is difficult to efficiently wash the laundry Q by the water flow (refer to the water level shown by the thick broken line in Fig. 6). In this case, the microcomputer 21 enhances the water flow intensity after the pulsator 5 restarts rotation by upgrading the set value of the water flow (step S18). Thereby, the cloth rotation becomes good, so that the laundry Q can be efficiently washed by the intensity-enhanced water flow.

By using the conventional water level detecting unit 28 as described above, the cloth rotation state can be detected at low cost, and the occurrence of splashing water can be suppressed or the cloth rotation can be improved. In particular, since the microcomputer 21 detects the water level decrease amount ΔF in the pause cycle in which the rotation of the pulsator 5 is stopped, not in the stirring cycle, the detection accuracy of the water level decrease amount ΔF can be improved. Further, the microcomputer 21 calculates the water level decrease amount Δf based on the difference between the water level fr detected by the water level detecting unit 28 after the predetermined period of time and the set water level f during the cleaning process, and obtains the final water level decrease amount based on the water level decrease amount Δf. ΔF (steps S114 to S119). The predetermined period of time is at least one of the following: from the start of washing (step S6) to the period until the number of times of detection N becomes 2 (NO in step S114); and from the pulsator 5 in each of the second and subsequent pause cycles. The above-described 4 seconds after the start of the rotation is interrupted (YES in step S115). Therefore, in the case of step S115, since the water level decrease amount ΔF with a small deviation can be obtained from the difference between the water level fr which is stabilized by the predetermined period of 4 seconds and the set water level f, the cloth rotation state can be accurately detected. Further, in the case of step S114, the water level in the first pause cycle can be changed in the same manner as the above-described 4 second water level after the start of each of the second and subsequent pause cycles, and therefore is not used for the calculation of the water level decrease amount ΔF. (YES in step S114), the correct water level decrease amount ΔF can be obtained.

Unlike the present embodiment, a pulse encoder that extracts the number of inertial rotation pulses when the motor 6 is turned off is separately provided, and based on the relationship between the number of inertial rotation pulses and the threshold value, the possibility of splashing water is determined, and the water is splashed. The difference in the number of inertial rotation pulses is small when the time is not splashed, so setting the relevant threshold is difficult in itself. However, in the case of the present embodiment, since the water level decrease amount Δf is significantly different from the case where water splashing is not performed (see FIG. 6), it is easy to set the first threshold value α and the second threshold value β described above.

The deviation of the water level decrease amount ΔF obtained by the cumulative value of the water level decrease amount Δf and the moving average value is small, and is significantly different depending on the difference in the rotation state of the cloth. Therefore, the detection accuracy of the water level decrease amount ΔF can be further improved. Thereby, the cloth rotation state can be accurately detected, the occurrence of splashing water can be effectively suppressed, or the cloth rotation can be effectively improved.

The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the invention.

For example, the water flow adjustment process (steps S11 to S18) may be performed only once in the initial stage of the cleaning process or in the cleaning process.

Further, although the washing machine 1 is a vertical washing and drying machine (see FIG. 1) in which the axis J of the washing tub 4 is vertically extended in the vertical direction Z, the washing machine 1 also includes the axis J slightly with respect to the up and down direction Z. The configuration of the oblique arrangement.

Claims

A washing machine, comprising:

Washing the tub to contain the laundry;

a water supply unit that supplies water to the washing tub;

a rotating member disposed in the washing tub;

The water flow generating unit intermittently rotates the rotating member to perform washing after the water is supplied to the set water level through the water supply unit, and generates water flow in the washing tub by the rotation of the rotating member. ;

a water level detecting unit that detects a water level in the washing tub;

The acquisition unit acquires a water level reduction amount in the washing tub based on a difference between a water level detected by the water level detecting unit during a rotation of the rotating member and the set water level during the cleaning process.

When the amount of water level decrease obtained by the acquisition unit is smaller than the first threshold value, the water flow generation unit reduces the intensity of the water flow.
A washing machine according to claim 1, wherein

When the water level decrease amount obtained by the acquisition unit is larger than the second threshold value greater than the first threshold value, the water flow generation unit enhances the intensity of the water flow.
A washing machine according to claim 1 or 2, characterized in that

The acquisition unit acquires the water level decrease amount based on a difference between a water level detected by the water level detecting unit after a predetermined period of time and the set water level in the cleaning process.