JP7614759B2 - washing machine - Google Patents

Description

The present invention relates to a washing machine.

There are washing machines that perform a "pre-wash process." The pre-wash process is performed before the "main wash" (see Patent Document 1).

JP 2018-130238 A

In Patent Document 1, dirt that dissolves in the cleaning solution during pre-washing may reattach to laundry.

The present invention aims to provide a washing machine that can prevent dirt removed from laundry during the pre-wash process from reattaching to the laundry.

The washing machine of the present invention comprises a washing tub, a water supply flow path, a water supply valve, a drainage flow path, a drainage valve, and a control unit. The washing tub stores laundry and cleaning liquid. The water supply flow path supplies water to the washing tub. The water supply valve controls the supply of water to the water supply flow path. The drainage flow path drains water from the washing tub to the outside. The drainage valve controls the drainage of water from the washing tub to the drainage flow path. The control unit executes a pre-wash process in which the laundry is washed while water is being supplied to the washing tub with the drainage valve open.

According to the present invention, it is possible to prevent dirt removed from laundry during the pre-wash process from reattaching to the laundry.

1 is a perspective view of a washing machine according to an embodiment of the present invention; FIG. 2 is a cross-sectional view of the washing machine according to the embodiment. FIG. 1 is a block diagram of a washing machine according to an embodiment. 13 is a flowchart of a pre-washing process. 1 is a flowchart of a washing course including a pre-wash. FIG. 2 is a perspective view of another washing machine according to the embodiment. FIG. 4 is a cross-sectional view of another washing machine according to the embodiment.

Embodiments of the present invention will be described below with reference to the drawings. Note that in the drawings, the same or equivalent parts will be given the same reference symbols and descriptions will not be repeated.

A washing machine 100 according to an embodiment of the present invention will be described with reference to Figures 1 to 3. Figure 1 is a perspective view of the washing machine 100 according to an embodiment. Figure 2 is a cross-sectional view of the washing machine 100. Figure 3 is a block diagram of the washing machine 100.

As shown in FIG. 1, the washing machine 100 of the embodiment is a vertical washing machine. The washing machine 100 includes a housing 101, a lid 102, and an operation display unit 103. The housing 101 is a casing that houses each device and each unit therein. The washing machine 100 may also include a laundry drying function.

As shown in FIG. 2, the housing 101 has an opening 104 at the top. The lid 102 closes the opening 104. The lid 102 is supported by a hinge so that it can be opened and closed.

The operation display unit 103 is provided on the upper part of the housing 101. The operation display unit 103 includes a display device 40. The display device 40 has a display unit 41 and an input unit 42 (see FIG. 3).

The internal structure of the washing machine 100 will be described. As shown in FIG. 2, the washing machine 100 internally comprises a water tub 1, a balancer 2, a water supply unit 10, three water supply valves (first water supply valve 11, second water supply valve 12, and third water supply valve 13), a drain unit 20, a drain valve 21, and a drive unit 30. The drive unit 30 includes a drive motor 31, a drive shaft 32, a rotating tub 33 (drum), and an agitator 34. As shown in FIG. 3, the washing machine 100 further comprises various sensors 51 to 53, a detergent dispenser 60, a control device 70, and a memory unit 80.

The water tub 1 and the spin tub 33 are cylindrical containers with a bottom. In the vertical washing machine 100, the water tub 1 and the spin tub 33 are open at the top. The water tub 1 and the spin tub 33 have an opening 22 in approximately the center of the bottom surface. The opening 22 penetrates the bottom of the water tub 1 and the spin tub 33. The opening 22 functions as a drain port for draining water from within the spin tub 33. Hereinafter, the opening 22 may be referred to as the "drain port 22."

The rotating tub 33 is disposed inside the water tub 1. With the lid 102 open, laundry is placed into the rotating tub 33 through the opening 104. The rotating tub 33 rotates when driven by the drive motor 31.

The balancer 2 is a weight. The balancer 2 is attached around the opening of the rotating tub 33. The balancer 2 suppresses the eccentric rotation of the rotating tub 33 (so-called miso grinding motion).

In addition, the spin tub 33 of the washing machine 100 of the embodiment is a so-called "holeless tub" in that the side wall (circumferential surface) does not have any holes that communicate with the water tub 1. Therefore, the spin tub 33 can store water by itself. The spin tub 33 is an example of a washing tub that stores laundry and cleaning solution.

The agitating member 34 is, for example, a pulsator. The agitating member 34 agitates the laundry. Hereinafter, the agitating member 34 may be referred to as "pulsator 34."

The pulsator 34 is disposed at the bottom of the rotating tub 33. The pulsator 34 rotates or oscillates independently of the rotating tub 33 by being driven by the drive motor 31 via the drive shaft 32. The drive shaft 32 is inserted through the drainage port 22 of the rotating tub 33.

The drive motor 31 drives the rotating tub 33 and the pulsator 34. The drive motor 31 rotates the rotating tub 33 and the pulsator 34 via a drive force transmission mechanism (not shown) and a drive shaft 32. The drive motor 31 is, for example, a DC (direct current) motor unit. The DC motor unit includes a rotation sensor 31a.

The drive motor 31 rotates the rotating tub 33 and the pulsator 34 independently via a drive force transmission mechanism. The drive force transmission mechanism includes, for example, a gear and a clutch. The drive force transmission mechanism can individually control the transmission of power to the rotating tub 33 and the pulsator 34.

The drive shaft 32 has a double shaft structure consisting of an agitation shaft and a spin-dry shaft. The agitation shaft is connected to the pulsator 34 and rotates the pulsator 34. The spin-dry shaft is connected to the rotating tub 33 and rotates the rotating tub 33.

The drive motor 31 rotates the pulsator 34 at the specified speed in response to instructions from the control device 70 (control unit). The rotation sensor 31a sends out a pulse as feedback information each time the motor rotates a certain angle. The control device 70 (capacity acquisition unit 71 or fabric quality acquisition unit 72) uses this pulse to measure the load (torque) of the motor.

The motor load (torque) measured using the pulses sent from the rotation sensor 31a is used for capacitance (cloth amount) sensing or cloth quality sensing. In other words, the rotation sensor 31a is an example of the "cloth quality sensor" of the present invention.

As shown in FIG. 3, the water supply unit 10 includes a first water supply valve 11, a second water supply valve 12, and a third water supply valve 13. The water supply unit 10 further includes a first water supply passage W1, a second water supply passage W2, and a third water supply passage W3 that are connected to the water supply valves 11, 12, and 13, respectively. Note that only the third water supply passage W3 is shown in FIG. 2.

The upstream sides of the first water supply passage W1, the second water supply passage W2, and the third water supply passage W3 are connected to a water source such as a water faucet. Water supplied from the water source branches toward the first water supply passage W1, the second water supply passage W2, and the third water supply passage W3 upstream of the first water supply valve 11, the second water supply valve 12, and the third water supply valve 13.

As shown in FIG. 2, the third water supply passage W3 sprays water directly onto the laundry in a shower-like manner without passing through the detergent dispenser or fabric softener dispenser. Note that the first water supply valve 11 and the second water supply valve 12 may be arranged as a single switching valve rather than as separate opening and closing valves.

The detergent dispenser 60 includes a detergent dispenser, a fabric softener dispenser, and a feed pump 61. The detergent dispenser includes a detergent tank 64 and a detergent supply valve 62. The fabric softener dispenser includes a fabric softener tank 65 and a fabric softener supply valve 63.

The detergent dispenser is disposed, for example, in the flow path (flow passage) of the first water supply passage W1. The detergent tank 64 stores liquid detergent for clothes. The supply pump 61 supplies the liquid detergent in the detergent tank 64 to the first water supply passage W1 via the detergent supply valve 62. The detergent supply valve 62 is an electromagnetic opening/closing valve whose opening and closing is controlled by the control device 70.

While the detergent supply valve 62 is open, detergent pumped from the detergent tank 64 by the feed pump 61 is introduced into the first water supply passage W1. When the first water supply valve 11 of the water supply unit 10 is opened and water flows into the first water supply passage W1, the detergent introduced into the first water supply passage W1 is carried by the water flow and introduced into the rotating tub 33. This is sometimes described as "automatic detergent introduction."

In this embodiment, the water supply unit 10 includes a detergent storage case 14 and a fabric softener storage case 15. The detergent storage case 14 is located at the end of the water flow path (flow path) of the first water supply passage W1. Similarly, the fabric softener storage case 15 is located at the end of the water flow path (flow path) of the second water supply passage W2.

If the detergent prepared by the user is stored in the detergent storage case 14 in advance, when water flows through the first water supply passage W1, the detergent stored in the detergent storage case 14 is poured into the rotating tub 33 by the flow of water. This is sometimes referred to as "manually adding detergent."

The same applies to adding fabric softener. If liquid fabric softener for clothes is stored in the fabric softener tank 65 beforehand, the fabric softener supplied from the fabric softener tank 65 is added to the rotating tub 33 via the second water supply passage W2 while the fabric softener supply valve 63 is open.

Furthermore, if fabric softener is stored in advance in the fabric softener storage case 15, the fabric softener stored in the fabric softener storage case 15 can be poured into the rotating tub 33 by being carried by the water flowing through the second water supply passage W2.

The drain section 20 includes a drain valve 21, a drain port 22 (opening), and, as shown in FIG. 2, drain channels 23, 24, and an external drain channel 25. The drain channel 23 allows water to flow down from the drain port 22 of the rotating tub 33 to the drain valve 21. The drain channel 24 drains the water from the dehydration process that has accumulated in the water tank 1. The external drain channel 25 guides the wastewater from the rotating tub 33 and the water tank 1 to the outside of the machine.

The drain valve 21 is an electromagnetic on-off valve. The opening and closing of the drain valve 21 is also controlled by a command signal from the control device 70. Therefore, the amount of water (water level) in the rotating tub 33 is controlled based on the command from the control device 70.

During the dehydration process by rotating the rotating tub 33, water that overflows from the top of the rotating tub 33 into the water tub 1 is constantly drained outside the machine via the drainage channel 24 and the external drainage channel 25.

The washing machine 100 of this embodiment further includes a circulation pump 35. The circulation pump 35 circulates the cleaning liquid that has flowed out from the drain outlet 22 to just before the drain valve 21 (upstream side) back into the spin tub 33 without discharging it outside the machine. The circulation pump 35 may be omitted.

The washing machine 100 will be further described with reference to Figure 3.

As shown in FIG. 3, the display device 40 receives instructions for the washing machine 100. The input unit 42 of the display device 40 includes a group of operation keys. The display unit 41 displays various information.

The display unit 41 is, for example, a display such as an LCD (Liquid Crystal Display) or an ELD (Electro Luminescence Display). The display unit 41 may include a touch panel and function as the input unit 42.

The washing machine 100 is equipped with multiple sensors to obtain information about the washing. The multiple sensors include a cleaning liquid sensor 51, a water level sensor 52, and a foam sensor 53.

The cleaning liquid sensor 51 detects the state of the cleaning liquid in the washing tub. The cleaning liquid sensor 51 includes, for example, an optical transmittance detector. When the cleaning liquid sensor 51 includes an optical transmittance detector, the cleaning liquid sensor 51 detects the light transmittance of the cleaning liquid. The light transmittance of the cleaning liquid corresponds to the turbidity of the cleaning liquid. The control device 70 (dirt determination unit 73) obtains information (data) regarding the degree of dirt on the laundry, the concentration of dirt in the cleaning liquid, and the concentration of detergent in the cleaning liquid based on the light transmittance of the cleaning liquid (turbidity of the cleaning liquid).

The water level sensor 52 detects the height of the water surface (liquid surface) in the washing tub. The water level sensor 52 includes, for example, a non-contact water level gauge. The water level sensor 52 transmits the detected water surface height in the washing tub to the control device 70. The control device 70 (fabric quality acquisition unit 72) acquires data on the fabric quality of the laundry and the concentration of the cleaning liquid based on the water level (liquid surface height) in the washing tub detected by the water level sensor 52.

The foam sensor 53 detects the height or amount of foam (detergent foam) generated in the washing tub and transmits it to the control device 70. The foam sensor 53 is, for example, a conductivity meter that detects electrical continuity (short circuit) between leads (terminals). The control device 70 obtains data on the degree of soiling of the laundry, the concentration of the cleaning liquid, and the hardness of the water used for washing based on the height or amount of foam in the washing tub detected by the foam sensor 53. The foam sensor 53 may be omitted.

The storage unit 80 includes a main storage device such as a ROM (Read Only Memory) and a RAM (Random Access Memory). The storage unit 80 may also include an auxiliary storage device such as a HDD (Hard Disk Drive). The storage unit 80 stores various computer programs and various data.

As shown in FIG. 3, the control device 70 includes a capacity acquisition unit 71, a fabric quality acquisition unit 72, and a dirt determination unit 73. The control device 70 is an example of a control unit of the present invention.

The control device 70 includes a processor such as a CPU (Central Processing Unit). The control device 70 controls each element of the washing machine 100 by executing a computer program stored in the memory unit 80.

The capacity acquisition unit 71 acquires the capacity (dry weight and wet weight) of the laundry in the washing tub by calculation based on the change in the rotation pulses sent as feedback by the rotation sensor 31a.

The fabric quality acquisition unit 72 acquires the water absorption rate of the laundry, which indicates the fabric quality of the laundry in the washing tub, by calculation based on the change in the rotation pulses transmitted as feedback by the rotation sensor 31a. The fabric quality acquisition unit 72 may acquire the fabric quality of the laundry based on the change in the water level (liquid surface height) in the washing tub detected by the water level sensor 52.

The dirt determination unit 73 determines the degree of dirt on the laundry, the concentration of dirt in the cleaning liquid, and the concentration of detergent in the cleaning liquid based on the turbidity of the cleaning liquid in the washing tub detected by the cleaning liquid sensor 51.

The pre-wash process and the pre-wash rinsing process performed by the washing machine 100 will be described with reference to FIG. 4. FIG. 4 is a flowchart of the pre-wash process and the pre-wash rinsing process. Note that the flowchart in FIG. 4 describes a case where a "pre-wash" is performed using the washing machine 100 equipped with the vertical washing tub (rotary tub 33) and the pulsator 34 shown in FIG. 1.

[Pre-washing process] (steps S1 to S8)
When the control device 70 starts the "pre-wash process", first, in step S1, it checks whether the laundry has been put into the washing tub and whether the lid 102 of the housing 101 is closed to ensure the safety of the user. In this embodiment, the laundry to be washed is put into the washing tub all at once before the selection of the washing course.

When the lid 102 is closed and the "start" button on the washing machine 100 is pressed, the control device 70 performs capacity sensing in step S2.

Capacity sensing is a step in which the dry weight (weight before water absorption) of the laundry placed in the washing tub is measured. Specifically, the drive motor 31 is rotated at a rotation speed instructed by the control device 70, and the rotation speed at that time (rotation pulse: measured value) is obtained by the rotation sensor 31a.

The capacity acquisition unit 71 of the control device 70 uses the acquired rotation pulses to measure the "number of input pulses" from when the motor is turned on until a certain time after the motor is turned off, and the time until the motor stops, thereby measuring the load (torque).

That is, the capacity acquisition unit 71 acquires the capacity of the dry laundry before the start of the wash by calculation based on the change in the rotation pulses sent as feedback by the drive motor 31. The capacity acquisition unit 71 then stores the acquired data in the memory unit 80 for use in the process of determining the amount of washing water for the "main wash" described below (FIG. 5, step S51).

Next, in step S3, the control device 70 sends a signal to the drain valve 21 to open the on-off valve. This causes the washing tub (spinning tub 33) to not store water and to constantly drain water.

Next, in step S4, the control device 70 opens one of the water supply valves to start supplying water to the washing tub. Here, one water supply valve is selected as the third water supply valve 13, which is not connected to the detergent dispenser or fabric softener dispenser and which dispenses only water into the washing tub.

In detail, a signal is sent to the third water supply valve 13 to open the valve. This causes water that does not contain detergent to be supplied in a shower-like manner onto the laundry in the washing tub (spinning tub 33) via the third water supply passage W3.

If the washing tub is not set to contain detergent or fabric softener, water may be supplied to the washing tub via the first water supply passage W1 (first water supply valve 11) or the second water supply passage W2 (second water supply valve 12). In either case, however, only water that does not contain detergent is supplied to the washing tub (spin tub 33).

While continuing to supply shower-like water, the control device 70 starts driving the washing tub and rotates the spin tub 33 in step S5.

Next, in step S6, while rotating the rotating tub 33, the pulsator 34 is driven to rotate synchronously with the rotating tub 33. The rotation direction of the pulsator 34 may be the same as that of the rotating tub 33 or may be opposite to that of the rotating tub 33.

In step S7, the control device 70 continues to supply water from the third water supply passage W3 and rotate the rotating tub 33 and pulsator 34. Then, after a predetermined time (in this case, about 1 to 10 minutes) has elapsed, in step S8, the control device 70 ends the "pre-wash process" and moves to the "pre-wash rinsing process" (steps S9 to S15).

In the above "pre-wash process" (steps S3 to S8), the drain valve 21 is always in the "open" state during the pre-wash. Therefore, the water supplied from the third water supply passage W3 onto the laundry in the spin tub 33 and used to remove dirt from the laundry does not remain in the spin tub 33 but is successively drained.

As a result, dirt that has been removed from the laundry during the pre-wash process does not return (reattach) to the laundry. Therefore, the washing machine 100 of this embodiment can prevent dirt that has been removed from the laundry during the pre-wash process from reattaching to the laundry.

[Pre-washing and rinsing process] (steps S9 to S17)
Next, as soon as the "pre-washing and rinsing process" starts in step S9, a signal is sent to the drain valve 21 in step S10 to close the on-off valve. This makes the washing tub (spinning tub 33) ready to store water.

Next, in step S11, a signal is sent to one of the water supply valves, for example the third water supply valve 13 that puts only water into the washing tub, to open the on-off valve and supply rinsing water to the spin tub 33. As in step S4, if the setting is such that no detergent or fabric softener is put into the washing tub, water may be supplied to the washing tub via the first water supply passage W1 (first water supply valve 11) or the second water supply passage W2 (second water supply valve 12).

While continuing to supply water that does not contain detergent, the control device 70 starts driving the washing tub in step S12, rotating the spin tub 33. The pulsator 34 may be driven simultaneously with the spin tub 33 to rotate the pulsator 34 (step S13).

Next, when the water supply to the washing tub, which has been maintained since step S11, reaches a predetermined amount (a predetermined "water level" set for pre-wash rinsing), in step S14, the opening/closing valve of the third water supply valve 13 is closed to stop the water supply to the washing tub.

The specified "water level" set for pre-wash rinsing is the "water level" obtained by calculation based on the dry weight (weight before water absorption) of the laundry obtained in "capacity sensing" in step S2.

However, the specified "water level" set for pre-wash rinsing is different from the washing water level for the "main wash" (step S45) or the water level for the "rinse" (step S50), which are set based on the dry weight (weight before water absorption) of the same laundry, and is kept low, below the water levels for the "main wash" and "rinse".

To determine whether the water supply to the washing tub has reached a predetermined amount (predetermined water level), for example, the water level sensor 52 may be used to detect the water level (liquid level) in the washing tub and transmit the detected water level to the control device 70. Based on the acquired detection results (water level data), the control device 70 determines whether the water level in the washing tub has reached a predetermined "water level" set for pre-wash rinsing.

When it is confirmed that the water level in the washing tub has reached a predetermined "water level" and the supply of water to the washing tub is stopped (step S14), the control device 70 performs "fabric quality sensing" in step S15.

Fabric quality sensing is different from volume sensing and is a step in which the wet weight (absorbed water weight) of the laundry placed in the washing tub is measured.

Specifically, similar to step S2, the drive motor 31 is rotated at a rotation speed instructed by the control device 70, and the rotation speed (rotation pulse: measured value) at that time is acquired by the rotation sensor 31a. Then, the fabric quality acquisition unit 72 acquires the volume (weight) of the laundry in an absorbed state by calculation based on the change in the rotation pulse (torque) transmitted as feedback by the rotation sensor 31a of the drive motor 31.

Then, the fabric quality acquisition unit 72 stores the acquired data in the storage unit 80 in the process of determining the amount of washing water for the "main wash" described below (FIG. 5, step S51). This data is later used to correct the planned amount of water to be added obtained by capacity sensing (step S2) according to the actual weight of the laundry after water absorption.

In addition, instead of performing fabric quality sensing, a second "capacity sensing (2nd)" may be performed using the capacity acquisition unit 71. The weight of the laundry after water absorption can also be obtained by the second "capacity sensing (2nd)".

Next, in step S16, the control device 70 performs "dirt sensing." Dirt sensing is a step in which the cleaning liquid sensor 51 is used to measure the turbidity (light transmittance) of the cleaning liquid (here, "rinse water") that has become cloudy due to "dirt" dissolved from the laundry placed in the washing tub.

Specifically, dirt sensing uses the cleaning liquid sensor 51 (light sensor) to detect the turbidity (light transmittance) of the water (cleaning liquid) in the washing tub. In more detail, the dirt determination unit 73 of the control device 70 determines whether the concentration of dirt in the cleaning liquid or the concentration of detergent in the cleaning liquid is appropriate based on the turbidity of the cleaning liquid in the washing tub detected by the cleaning liquid sensor 51.

Here, the amount of detergent and water to be dispensed in the "main wash" (steps S61 and S62) is adjusted based on the result of the dirt determination. In other words, the amount of detergent to be used in the "main wash" (step S63) is finally adjusted and determined here.

If the amount of detergent is already appropriate, the amount of detergent may not be adjusted. Similarly, the amount of water added in the "main wash" (steps S61 and S62) is also adjusted based on the results of the soiling determination. If the amount of water is already appropriate, water may not be added.

As described above, when fabric quality sensing (step S15) and dirt sensing (step S16) are completed, the control device 70 stops driving the rotating tub 33 and the pulsator 34 in step S17 to stop rotation. It also sends a signal to the drain valve 21 to open the on-off valve, drains the water from the washing tub, and ends the pre-wash and rinsing process.

If the "turbidity" result obtained by the dirt sensing in step S16 exceeds a predetermined threshold value and it is determined that the "pre-wash" has not sufficiently removed the dirt, the "pre-wash process" in steps S2 to S8 and the "pre-wash rinsing" in steps S9 to S16 may be repeated in the order of the steps.

In addition, in FIG. 4, the next step after the completion of the "pre-wash rinsing process" (steps S9 to S17) is described as "proceed to spin-dry process", but if the "turbidity" result obtained by the dirt sensing in step 16 is a low value below a predetermined value, the drainage process (step S17) or spin-dry process (pre-wash spin-dry) may not be performed, and the stored rinse water may be used as the washing water for the "main wash".

Next, referring to FIG. 5, a case where the washing machine 100 performs an entire washing course including a "pre-wash process" will be described. FIG. 5 is a flowchart of a washing course including a pre-wash process. Note that the "pre-wash" (step S40) and "pre-wash rinsing" (step S50) in FIG. 5 are the same as the "pre-wash process" (steps S1 to S8) and "pre-wash rinsing process" (steps S9 to S14) in FIG. 4, and therefore detailed explanations will be omitted.

When the power is turned on, the washing machine 100 first displays a menu, list, etc. on the display device 40 and accepts the specification of the "washing course" to be used (step S20).

The following flow explanation will be given for the case where, in step S20, the "pre-wash + main wash" course is selected when the laundry contains heavily soiled laundry (step S30).

In step S30, when the "pre-wash + main wash" course is selected and input, the washing machine 100 then accepts the reservation of the end time of the course and details of the course content. At this time, it is possible to select whether or not to use detergent when performing the "pre-wash", whether or not to store water when performing the "pre-wash", whether or not to add additional laundry after performing the "pre-wash" and before performing the "main wash", etc.

When the washing course is decided and the washing start button of the washing machine 100 is pressed, the "pre-wash + main wash" course will start immediately if no time is specified, or at the specified (reserved) time if a time is specified.

In step S40, the control device 70 executes the "pre-wash process" described in steps S1 to S8 of FIG. 4. That is, the "pre-wash" in step S40 first executes "capacity sensing" (step S2) to obtain the dry weight (weight before water absorption) of the laundry placed in the washing tub, and stores the obtained result (data) in the memory unit 80.

In addition, the "pre-wash" in step S40 does not use detergent, and with the drain valve 21 open, a shower of water is supplied from the third water supply passage W3 onto the laundry in the washing tub (rotating tub 33) while rotating the rotating tub 33 and pulsator 34, and dirt that has dissolved into the water is immediately discharged outside the washing tub. This makes it possible to prevent dirt that has come off the laundry during the pre-wash from re-adhering to the laundry.

Next, in step 50, the "pre-wash rinsing process" described in steps S9 to S14 of FIG. 4 is executed. At this time, the control device 70 executes fabric quality sensing (step S15) and soiling sensing (step S16) at the end of the "pre-wash rinsing process."

Here, the control device 70 can accurately determine the appropriate amount of water required for the "main wash" (step S63) by calculation based on the wet weight (absorbed weight) of the laundry obtained by fabric quality sensing (step S15) and the dry weight (weight before water absorption) of the washed laundry obtained by capacity sensing (step S2) stored in the memory unit 80 (step S51).

In addition, the weight of the laundry after the spin-drying process (pre-wash spin-drying) (weight after pre-wash spin-drying) may be used instead of or in addition to the wet weight (absorbed weight) of the laundry. That is, in addition to obtaining information on fabric quality from the pre-absorption weight and absorbed weight of the laundry as described above, information on fabric quality can be obtained from the pre-absorption weight and the weight after pre-wash spin-drying. Alternatively, information on fabric quality may be obtained from the pre-absorption weight, absorbed weight, and weight after pre-wash spin-drying. Then, based on the information on fabric quality, the appropriate amount of water required for the main wash can be accurately determined.

In addition, the control device 70 can accurately determine the appropriate amount of detergent required for the "main wash" (step S63) in step S52 by calculation based on the turbidity of the cleaning liquid (water) during the pre-wash rinse obtained in the dirt sensing (step S16).

As described above, the effect of the main wash or the second or subsequent pre-washes can be improved by performing the drainage process (step S17) and spin-drying process (pre-washing spin-drying) described in FIG. 4 after performing the pre-washing and rinsing process in step S50. However, if the result of the "turbidity" obtained by the dirt sensing in step S16 is a low value below a predetermined value, the drainage process (step S17) or spin-drying process (pre-washing spin-drying) may not be performed, and the stored rinse water may be used as washing water for the "main wash". By reusing the rinse water, the amount of water in the entire washing course can be reduced and the washing time can be shortened. The drainage process (step S17) or spin-drying process (pre-washing spin-drying) may be performed after performing step S50 and before performing step S60.

Next, in the "main wash" of steps S60 to S63, the amount of "water" set in step S51 is poured into the washing tub from the water supply unit 10, and the amount of "detergent" set in step S52 is poured into the washing tub from the detergent dispenser 60.

Specifically, in the water supply step (step S61), the control device 70 selects the first water supply passage W1 connected to the detergent dispenser from among the first water supply passage W1, the second water supply passage W2, and the third water supply passage W3 that constitute the water supply section 10, and opens the first water supply valve 11 to start supplying water.

The amount of water to be poured into the washing tub during the main wash was set in step S51, so the control device 70 pours water into the spin tub 33 to match that set amount of water.

In detail, the control device 70 controls the opening and closing of the first water supply valve 11 that supplies water to the first water supply passage W1 while monitoring the water level (liquid level) in the rotating tub 33 detected by the water level sensor 52. This prevents excessive water from being added, thereby reducing water usage (saving water).

Next, with a delay after the addition of water using the first water supply passage W1 (step S61), the control device 70 starts the detergent supply step (step S62). This is to prevent the detergent from adhering to the laundry as a concentrated "undiluted solution" and damaging the fabric of the laundry. The time (time lag) by which the addition of detergent (step S62) starts after the addition of water (step S61) can be set arbitrarily to a time of about 1 to 10 minutes.

Specifically, the detergent introduction step (step S62) starts several minutes after the start of water introduction (step S61). The detergent is introduced by using the feed pump 61 to introduce detergent from the detergent introduction section (detergent tank 64) of the detergent introduction device 60 into the first water supply passage W1, through which water is already flowing due to the first water supply valve 11 being open.

In detail, the supply pump 61 is started and the on-off valve of the detergent supply valve 62 is opened by a signal. This allows the detergent stored in the detergent tank 64 to be mixed with the water flowing through the first water supply passage W1 and poured into the rotating tub 33. In addition, the rotation of the rotating tub 33 and the pulsator 34 may be started in conjunction with the start of the detergent supply (step S62), and the main wash (step S63) may be started.

In addition, even during the main wash (step S63), the rotation torque based on the pulses detected by the rotation sensor 31a may be obtained to monitor whether the amount of water and the amount of detergent (concentration) are appropriate. As a result, additional water or detergent, or both, may be added.

Furthermore, during the main wash (step S63), the turbidity (light transmittance) of the cleaning liquid in the washing tub detected by the cleaning liquid sensor 51 may be obtained to monitor whether the amount of water and the amount of detergent (concentration) are appropriate, or whether the degree of dirt removal is sufficient. If the result is insufficient, additional water or detergent, or both, may be added.

After driving and rotating the rotating tub 33 and pulsator 34 for a predetermined time, the main wash (step S63) is completed.

After the main wash is completed, as shown in FIG. 5, the normal rinse process (step S70) and spin-dry process (step S80) are performed, and the specified washing course ends.

During the rinsing process (step S70), if the turbidity (light transmittance) of the cleaning liquid in the washing tub detected by the cleaning liquid sensor 51 is obtained and it is determined that the degree of dirt removal is insufficient, the "pre-wash process" - "main wash" - "rinse" or "main wash" - "rinse" may be performed again.

Furthermore, during the rinsing process (step S70), the amount of water for rinsing may be set to the amount of water set in the previous step S51. This allows water consumption during rinsing to be reduced.

The above describes the embodiments of the present invention with reference to the drawings. However, the present invention is not limited to the above embodiments, and can be implemented in various forms without departing from the gist of the present invention. For example, some components may be deleted from all components shown in the embodiments. The drawings are mainly schematic illustrations of each component for ease of understanding, and the thickness, length, number, spacing, etc. of each component shown in the drawings may differ from the actual ones due to the convenience of creating the drawings. In addition, the materials, shapes, dimensions, etc. of each component shown in the above embodiments are merely examples and are not particularly limited, and various modifications are possible within a range that does not substantially deviate from the configuration of the present invention.

In the embodiment described with reference to Figures 1 to 5, a vertical washing machine 100 (vertical washing tub) is used as an example, but the type and form of the washing machine of the present invention are not limited to the embodiment, and the present invention can be implemented in washing machines of various configurations.

With reference to Figures 6 and 7, a case where the washing machine of the embodiment is a drum type (horizontal drum type) washing machine 200 will be described. Note that in the figures, the same reference numerals are used for the same or equivalent parts as those of the vertical washing machine 100, and the description will be omitted.

Figure 6 is a perspective view of the drum type washing machine 200, and Figure 7 is a cross-sectional view of the drum type washing machine 200. The block diagram of the drum type washing machine 200 is omitted because it is the same as that of Figure 3 except that the reference numeral "100" indicating the washing machine is replaced with "200".

The drum type washing machine 200 differs from the vertical washing machine 100 in appearance in that it includes a housing 201, a lid 202, an operation display unit 203, and an opening/closing button 205 for the lid 202. It also includes an opening 204 similar to the opening 104.

The internal structure shown in FIG. 7 differs from that of the vertical washing machine 100 in that the drain section 20 includes a drain valve 21, a drain port 22 (opening), a drain channel 23, and an external drain channel 25.

In addition, instead of a pulsator 34 as the agitating member 34, ribs for lifting the laundry are arranged on the side wall (circumferential surface) of the rotating tub (drum) 33.

The rotation of the drive motor 31 is detected by a rotation sensor 31a, similar to the washing machine 100.

The drum-type washing machine 200 configured as described above can also perform the pre-wash process and the pre-wash rinse process shown in the flowchart of FIG. 4. Therefore, when steps S1 to S17 are performed, the drum-type washing machine 200, like the vertical washing machine 100, can prevent dirt removed from the laundry during the pre-wash process from re-adhering to the laundry.

This invention can be used in the field of washing machines.

REFERENCE SIGNS LIST 1 Water tank 10 Water supply unit 20 Drain unit 30 Drive unit 31 Drive motor 40 Display device 33 Rotating tank (drum)
60 Detergent dispenser 70 Control device 71 Capacity acquisition unit 72 Fabric quality acquisition unit 73 Stains determination unit 80 Memory unit 100 Washing machine 200 Washing machine

Claims (7)

A rotating tub that stores laundry and cleaning solution and rotates;
a water supply passage for supplying water to the rotating tub;
a water supply valve for controlling the supply of water to the water supply passage;
A drainage flow path for discharging water from the rotating tub to the outside;
a drain valve for controlling drainage of water from the rotating tub to the drain passage;
A detergent dispenser that dispenses detergent into the rotating tub;
and a control unit that executes a pre-wash process for washing the laundry while supplying water onto the laundry placed in the spin tub with the drain valve open, a dehydration process for dehydrating the laundry after the pre-wash process, and a washing process for washing the laundry by pouring water and the detergent into the spin tub after the dehydration process . The washing machine according to claim 1, wherein the control unit executes a pre-washing and rinsing process in which water is supplied to the spin tub and the spin tub is rotated with the drain valve closed after the pre-washing process and before the dehydration process. a cleaning liquid sensor for detecting a state of the cleaning liquid in the rotating tank;
The washing machine according to claim 2 , wherein the control unit performs dirt sensing to obtain a detection result of the cleaning liquid sensor when the pre-wash rinsing process is performed. a fabric quality sensor for detecting the fabric quality of the laundry,
The washing machine according to claim 3 , wherein the control unit performs fabric quality sensing to obtain a detection result of the fabric quality sensor. The control unit is
5. The washing machine according to claim 4, further comprising a step of determining an amount of detergent to be poured into the spin tub and an amount of water to be poured into the spin tub when performing the washing process, based on a state of the cleaning liquid detected by the cleaning liquid sensor and a fabric quality of the laundry detected by the fabric quality sensor . The washing machine according to claim 5 , wherein the control unit, when performing the washing process, starts pouring the detergent into the spin tub later than starting pouring of the water. a stirring member for stirring the laundry in the spin tub,
The washing machine according to claim 1 , wherein the control unit agitates the laundry using the agitating member when performing the pre-washing process.

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