Method of controlling washing machine

1. Field of the Invention

The present invention relates generally to a washing machine, and more particularly to a method of controlling a washing machine, which supplies water to the washing machine according to the amount of laundry load, thereby improving the washing performance of the washing machine.

2. Description of the Prior Art

FIG. 1 is a flowchart showing a conventional method of controlling a washing machine.

Referring to FIG. 1 , in the conventional washing machine control method, in order to wash a load of laundry, a user sets washing conditions through an input unit at step S 10 . In this case, the user can set the washing conditions by an automatic mode provided in the input unit or by manually inputting a particular washing mode.

When the setting of washing conditions is completed, water is supplied at step S 20 , and the water level of the tub is detected at step S 30 . Thereafter, it is determined whether the water level detected at step S 30 has reached the level set at step S 10 .

If as the result of the determination at step S 40 the water level of the tub has reached the set water level, water supply is stopped at step S 50 . Thereafter, the washing of the laundry is performed at step S 60 . The washing of step S 60 may include a washing process, a rinsing process and a spin-drying process.

In the conventional washing machine control method, once a water level is set, water is supplied according to the set water level without regard to the amount of laundry load, so laundry may not be uniformly wetted at the early stage of washing when the load is relatively heavy. This may result in inefficient and/or incomplete washing and/or rinsing processes. Moreover, the uneven wetting of the laundry may result in the uneven distribution of the laundry causing an unbalance, which may result in noises and/or vibration in the spin-drying process.

Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a method of controlling a washing machine, which supplies water to the washing machine according to the amount of laundry load, thereby improving the washing performance of the washing machine.

In order to accomplish the above object, the present invention provides a method of controlling a washing machine, comprising: detecting a load of laundry; determining a basic water supply level commensurate with said detected load; and supplying said basic water supply level through a plurality of stages, a corresponding apportionment of said basic water supply level being supplied during each respective ones of said plurality of stages.

In addition, the present invention provides a method of controlling a washing machine having a wobbling device, the wobbling device being switched to a leveling position to operate a spin-drying tub and a washboard and to a wobbling position to operate the washboard, comprising: detecting a load of laundry; determining a basic water supply level commensurate with said detected load; and supplying said basic water supply level through a plurality of stages, a corresponding apportionment of said basic water supply level being supplied during each respective ones of said plurality of stages, wherein said wobbling device is switched to said wobbling position during least one of said plurality of stages.

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a flowchart showing a conventional method of controlling a washing machine;

FIGS. 2 a and 2 b are sectional views of an illustrative embodiment of a washing machine with a wobbling device according to the principles of the present invention, showing the interior structure thereof, FIG. 2 a illustrating the washing machine in which the wobbling device is switched to a leveling position so as to perform a spin-drying process, and FIG. 2 b illustrating the washing machine in which the wobbling device is switched to a wobbling position so as to perform a washing process;

FIG. 3 is a block diagram of an exemplary embodiment of a washing machine control system in accordance with the principles of the present invention;

FIG. 4 is a flowchart showing an exemplary embodiment of a method of controlling the washing machine in accordance with the principles of the present invention;

FIG. 5 is a detailed flowchart showing a water supply setting step of the method in accordance with the principles of the present invention shown in FIG. 4 ; and

FIGS. 6 a to 6 c are flowcharts showing the water supply steps for the small, medium and large load, respectively, of the method in accordance with the present invention shown in FIG. 4 .

Reference now should be made to the drawings, in which the same reference numerals are used throughout the different drawings to designate the same or similar components.

FIGS. 2 a and 2 b are longitudinal cross-sectional views showing the interior structure of a washing machine with a wobbling device 4 , FIG. 2 a illustrating the washing machine in which the wobbling device 4 is switched to a leveled position so as to perform a spin-drying process, FIG. 2 b illustrating the washing machine in which the wobbling device is switched to a wobbling position so as to perform a washing process. The “leveled position” designates the position in which the wobbling device 4 allows a washboard 4 a to be leveled horizontally and prevents a wobbling operation, while the “wobbling position” designates the position in which the wobbling device 4 allows the washboard 4 a to be slanted and permits a wobbling motion of the washboard 4 a.

Referring to FIGS. 2 a and 2 b , the washing machine in accordance with this exemplary embodiment of the present invention is comprised of an outer tub 2 mounted in a housing 1 , a spin-drying tub 2 mounted in the outer tub 2 and provided with a plurality of spin-drying holes 3 c , and a drive motor 5 and a power transmission device 6 positioned under the outer tub 2 . Additionally, the wobbling device 4 is disposed in the lower portion of the spin-drying tub 3 to carry out a wobbling or leveling operation, in which the washboard 4 a is slanted or leveled, respectively.

The top of the housing 1 is opened to allow the laundry to be put into and to be taken out from the housing 1 . A door 7 is hingedly attached to the opened top of the housing 1 to selectively open and close the spin-drying tub 3 .

A drain hose 8 is extended from the outer tub 2 to the outside so as to discharge washing water contained in the outer tub 2 to the outside after the washing of the laundry is completed.

A spin-drying shaft support 9 is mounted beneath a bottom plate 3 a of the spin-drying tub 2 and a spin-drying shaft 6 a of the power transmission device 6 is passed through the spin-drying shaft support 9 , thus rotating the spin-drying tub 3 during a spin-drying process. A washing shaft 6 b is passed through the spin-drying shaft 6 a , with the upper end of the washing shaft 6 b slightly extended from the upper end of the spin-drying shaft 6 a so as to be coupled to the wobbling device 4 .

The wobbling device 4 is mounted towards the bottom of the spin-drying tub 3 , and serves to wash the laundry during the washing process by wobbling the laundry up and down in the wobbling position shown in FIG. 2 b , and to spin-dry the laundry during a spin-drying process by rotating together with the spin-drying tub 3 in the leveling position shown in FIG. 2 a.

FIG. 3 is a block diagram of an exemplary embodiment of the washing machine according to the present invention.

Referring to FIG. 3 , the washing machine includes a control unit 50 that controls the operation of the washing machine. An input unit 10 is electrically connected to the control unit 50 to receive information from a user. The input unit 10 is provided with, e.g., a plurality of keys that are used to set the washing conditions.

Additionally, a water level detector 20 for detecting the water level of the outer tub (not shown), a weight detector 30 for detecting the weight of the laundry, and a storage unit 40 for storing data are electrically connected to the control unit 50 .

Additionally, a motor drive unit 61 for operating a motor 62 , a transmission drive unit 71 for operating a transmission 72 , a water supply valve drive unit 81 for operating a water supply valve 82 , and a water discharge valve drive unit 91 for operating a water discharge valve 92 are electrically connected to the control unit 50 .

Furthermore, a display drive unit 101 for operating a display 102 to display the operational states of the washing machine and a buzzer drive unit 111 for operating a buzzer 112 to audibly indicate the operational states of the washing machine are electrically connected to the control unit 50 .

FIG. 4 is a flowchart showing a method of controlling the washing machine in accordance with the present invention.

Referring to FIG. 4 , a user selects a desired particular washing course or mode through the input unit 10 at step S 110 . Information inputted by the user through the input unit 10 is transmitted to the control unit 50 .

The control unit 50 detects the weight of laundry through the weight detector 30 at step S 120 . Thereafter, the control unit 50 calculates the amount of laundry load corresponding to the detected weight of the laundry, and sets water supply conditions according to the amount of laundry load at step S 200 .

After water supply conditions are set at step S 200 , the control unit 50 determines whether small-load water supply is set at step S 310 . If the small-load water supply is set at step S 310 , the control unit 50 performs the small-load water supply at step S 400 and the washing operation at step S 700 .

Meanwhile, if the small-load water supply is not set at step S 310 , the control unit 50 determines whether medium-load water supply is set at step S 320 . If the medium-load water supply is set at step S 320 , the control unit 50 performs the medium-load water supply at step S 500 and the washing operation at step S 700 .

However, if the medium-load water supply is not set at step S 320 , the control unit 50 decides that large-load water supply is set and performs the large-load water supply at step S 600 , and, thereafter, performs the washing operation at step S 700 .

The water supply condition setting step S 200 will now be described in more detail with references to FIG. 5 .

Referring to FIG. 5 , the control unit 50 determines whether the weight of the laundry detected at step S 120 (shown in FIG. 4 ) corresponds to a predetermined first reference load at step S 210 . In this exemplary embodiment, the first reference load may be, e.g., about 3 kg or less. If the weight of the laundry corresponds to the first reference load, that is, about 3 kg or less, at step S 210 , the control unit 50 sets a first total water supply level (the total amount of washing water to be supplied) according to the weight of the laundry. For example, if the weight of the laundry corresponds to the first reference load, the first total water supply level is set to about 30% of the maximum possible water supply level or less at step S 211 . Additionally, each water supply stage during the water supply is set to a small-load water supply stage at step S 212 .

In the small-load water supply stage, a primary water supply is performed to a basic water supply level (a water level lower than the first total water supply level, e.g., in this embodiment, ⅔ of the first total water supply level) through a predetermined number of sub-stages (for example, three sub-stages), and a secondary water supply is performed from the basic water supply level to the first total water supply level through a predetermined number of sub-stages (for example, two sub-stages).

Meanwhile, if the weight of the laundry does not correspond to the first reference load at step S 210 , the control unit 50 determines whether the weight of the laundry is less than a predetermined second reference load at step S 220 . If the weight of the laundry corresponds to the second reference load, that is, e.g.,6 kg, the control unit 50 sets a second total water supply level according to the weight of the laundry at step S 221 . If the weight of the laundry is heavier than the first reference load and lighter than the second reference load, the second total water supply level is set to 60% of the maximum possible water supply level or less. Additionally, each water supply stage during water supply is set to a medium-load water supply stage at step S 222 .

In the medium-load water supply stage, primary water supply is performed to a basic water supply level (a water level lower than the second total water supply level by a certain percentage; in this embodiment, ⅔ of the second total water supply level) through a predetermined number of sub-stages (for example, two sub-stages), and secondary water supply is performed from the basic water supply level to the second total water supply level through a predetermined number of sub-stages (for example, two sub-stages).

Meanwhile, if the weight of the laundry is greater than the second reference load at step S 220 , the control unit 50 sets a third total water supply level according to the weight of the laundry at step S 230 . If the weight of the laundry corresponds to the third reference load, the third total water supply level is set to 90% of the maximum possible water supply level or less. Additionally, each water supply stage during water supply is set to a large-load water supply stage at step S 240 .

In the large-load water supply stage, primary water supply is performed to a basic water supply level (a water level lower than the third total water supply level by a certain percentage, e.g., in this embodiment, ⅔ of the third total water supply level) continuously without sub-stages and secondary water supply is performed from the basic water supply level to the third total water supply level through a predetermined number of sub-stages (for example, two sub-stages).

Hereinafter, the small-load water supply step S 400 is described in detail.

FIG. 6 a is a detailed flowchart showing an exemplary embodiment of the small-load water supply step S 400 in accordance with the principles of the present invention. The small-load water supply includes primary water supply in which water is supplied to a basic water supply level and secondary water supply in which water is supplied from the basic water supply level to the first total water supply level. During the primary water supply, when water is supplied to a corresponding water supply level in each of the sub-stages (for example, first, second or third sub-stage water supply level). At each water supply sub-stage (for example, a total of three sub-stages), water supply is stopped, and the pulsator is operated for a predetermined period of time. This water supply pattern is applied to the secondary water supply as well.

Referring to FIG. 6 a , the control unit 50 starts water supply by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 401 . Additionally, the control unit 50 detects the water level of supplied water through the water level detector 20 at step S 402 . The control unit 50 determines whether the detected water level has reached the predetermined first sub-stage water supply level at step S 403 .

If the detected water level is the first sub-stage water supply level at step S 403 , the control unit 50 stops water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 404 . Additionally, the control unit 50 operates a pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 405 . Furthermore, the control unit 50 performs water supply by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 406 .

The control unit 50 detects the level of supplied water through the water level detector 20 at step S 407 . The control unit 50 determines whether a detected water level has reached a predetermined first sub-stage water supply level at step S 408 .

If the detected water level is the second sub-stage water supply level at step S 408 , the control unit 50 stops water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 409 . Additionally, the control unit 50 operates the pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 410 . Furthermore, the control unit 50 performs water supply by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 411 .

The control unit 50 detects the level of supplied water through the water level detector 20 at step S 412 . The control unit 50 determines whether a detected water level has reached a predetermined third sub-stage water supply level at step S 413 .

If the detected water level is the third sub-stage water supply level at step S 413 , the control unit 50 stops water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 414 . Additionally, the control unit 50 operates the pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 415 . Furthermore, the control unit 50 performs the secondary water supply to the first total water supply through a predetermined number of sub-stages (for example, two sub-stages) by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 416 .

Hereinafter, the medium-load water supply step S 500 is described in detail.

FIG. 6 b is a detailed flowchart showing an exemplary embodiment of the medium-load water supply step S 500 in accordance with the principles of the present invention. The medium-load water supply includes primary water supply in which water is supplied to a basic water supply level and secondary water supply in which water is supplied from the basic water supply level to the second total water supply level. During the primary water supply, when water is supplied to a corresponding water supply level in each of the sub-stages (for example, a first or second sub-stage water supply level). At each water supply sub-stage (for example, a total of two sub-stages), water supply is stopped, and the pulsator is operated for a predetermined period of time. This water supply pattern is also applied to the secondary water supply.

Referring to FIG. 6 b , the control unit 50 starts water supply by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 501 . Additionally, the control unit 50 detects the water level of supplied water through the water level detector 20 at step S 502 . The control unit 50 determines whether the detected water level has reached the predetermined first sub-stage water supply level at step S 503 .

If the detected water level is the first sub-stage water supply level at step S 503 , the control unit 50 stop water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 504 . Additionally, the control unit 50 operates the pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 505 . Furthermore, the control unit 50 supplies water by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 506 .

The control unit 50 detects the level of supplied water through the water level detector 20 at step S 507 . The control unit 50 determines whether a detected water level has reached a predetermined second sub-stage water supply level at step S 508 .

If the detected water level is the second sub-stage water supply level at step S 508 , the control unit 50 stops water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 509 . Additionally, the control unit 50 operates the pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 510 . Furthermore, the control unit 50 performs the secondary water supply to the second total water supply through a predetermined number of sub-stages (for example, two sub-stages) by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 511 .

Hereinafter, the large-load water supply step S 600 is described in detail.

FIG. 6 c is a detailed flowchart showing an exemplary embodiment of the large-load water supply step S 600 in accordance with the principles of the present invention. The large-load water supply includes primary water supply in which water is supplied to a basic water supply level and secondary water supply in which water is supplied from the basic water supply level to the third total water supply level. In the primary water supply, water is supplied continuously without sub-stages, and the pulsator is operated for a predetermined period of time when the water supply is stopped after the basic water supply level has been reached. In the secondary water supply, water supply and the stopping of water supply are alternately performed through a predetermined number of sub-stages (for example, a total of two sub-stages).

Referring to FIG. 6 c , the control unit 50 starts water supply by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 601 . Additionally, the control unit 50 detects the water level of supplied water through the water level detector 20 at step S 602 . The control unit 50 determines whether the detected water level has reached the predetermined first sub-stage water supply level at step S 603 . The first sub-stage water supply level of the large-load water supply is identical to the basic water supply level. That is, in the large-load water supply, the primary water supply is performed in a single stage.

If the detected water level is determined to have reached the first sub-stage water supply level at step S 603 , the control unit 50 stops the water supply by controlling the water supply valve drive unit 81 to close the water supply valve 82 at step S 604 . Additionally, the control unit 50 operates the pulsator (not shown) for a predetermined period of time by controlling the motor drive unit 61 to drive the motor 62 at step S 605 .

The control unit 50 then performs the secondary water supply to the third total water supply through a predetermined number of sub-stages (for example, two sub-stages) by controlling the water supply valve drive unit 81 to open the water supply valve 82 at step S 606 .

As described above, the present invention provides the method of controlling a washing machine, in which load is set according to the weight of the laundry, and water is supplied through a plurality of stages according to the load, so the laundry is rapidly and uniformly wetted, thereby improving the washing performance of the washing machine and preventing the generation of noise and/or vibration.

Although the preferred embodiment of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.