Patent Publication Number: US-2006016021-A1

Title: Washing method of washing machine

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a washing method of a washing machine, and more particularly, to a washing method of a washing machine, which allows laundry to be disentangled by means of an alpha-shaped water stream generated according to fast rotation of an inner tub while water is supplied into the washing machine.  
      2. Description of the Related Art  
       FIG. 1  is a diagram illustrating a general washing machine.  
      The general washing machine comprises a cabinet  2  defining an appearance of the washing machine, a door  1  provided on an upper surface of the cabinet, and a controller  4  provided to an outer surface of the cabinet to operate a washing machine and display a washing procedure.  
      The cabinet  2  is equipped therein with a barrel-shaped outer tub  6 , which is supported via a damper  7  and is opened at an upper surface thereof.  
      The outer tub  6  is connected at an upper portion to a water supply apparatus  10  for supplying water, and is connected at a lower portion to a draining device  12  for drainage of water.  
      The water supply apparatus may be structured such that water flows through a detergent barrel  14  located at an upper portion of the cabinet  2 .  
      A ring-shaped tub cover  5  is provided around an outer periphery of an upper end of the outer tub  6 .  
      The outer tub  6  is provided therein with an inner tub  8 , which has an open upper surface, and a plurality of holes (not shown) formed on a peripheral surface thereof, so as to be rotated in the outer tub  6 .  
      The inner tub  8  is provided at the bottom with a pulsator  9 .  
      The inner tub  8  and the pulsator  9  are directly connected to a motor  20  provided below the outer tub  6 , and are rotated by driving force of the motor  20 .  
      With the washing machine constructed as described above, an washing operation is generally performed according to the following sequence; a washing process for removing contaminants stuck to laundry such as clothes, a rising process for rinsing the laundry with the contaminants removed therefrom, and a dewatering process for removing water from the laundry. These processes can be selectively performed during the washing operation by a user.  
      The washing process, the rinsing process, and the dewatering process in the general washing machine will be described as follows.  
       FIG. 2  is a flow diagram illustrating the washing process of the general washing machine.  
      The washing process of the general washing machine will be described with reference to  FIGS. 1 and 2 .  
      After laundry is input to the inner tub  8 , and the door  1  is closed, the washing process is started, causing water to be supplied into the inner tub  8  (S 1 ). At this time, when detergent is contained in the detergent barrel  14 , the detergent is also supplied to the inner tub  8  together with the water (S 2 ).  
      After completing water supply, the inner tub  8  or the pulsator  9  is rotated for a predetermined time, generating a water stream. Then, contaminants stuck to the laundry are detached therefrom by virtue of interaction of the detergent and the water stream with the contaminants (S 4 ).  
      After the inner tub  8  or the pulsator  9  is stopped, the inner tub  8  is rotated again at a speed lower than that of the washing step as described above, thereby generating agitating force. Then, the laundry entangled during the washing step is disentangled while being agitated by the rotation of the inner tub  8  generating the agitation force. The disentangling step is typically performed for one minute (S 6 ).  
      Then, the water is drained from the washing machine (S 8 ), and an unbalance degree of the inner tub  8  is detected. Here, a large unbalance degree of the inner tub  8  results in movement of the washing machine due to severe vibration occurring when the inner tub  8  is rotated at a high speed, and provides a lower dewatering rate. Thus, it is necessary to provide the step of detecting the unbalance degree of the inner tub  8  (S 10 ).  
      When the unbalance degree of the inner tub  8  is deviated from an acceptable degree, the disentangle step in which the inner tub  8  is rotated at the low speed to generate the agitating force while being supplied with water is repeated once or more until the unbalance degree of the inner tub  8  reaches an acceptable degree. At this time, since the detergent barrel  8  is not refilled with the detergent before the washing operation of the laundry is finished, clean, detergent-free water is supplied thereto.  
      If it is determined through detection for the unbalance degree of the inner tub  8  that the unbalance degree of the inner tub  8  is the acceptable degree, a temporary dewatering step is performed (S 12 ), in which the inner tub  8  is rotated at a high speed so as to force water absorbed in the laundry to be extracted therefrom by centrifugal force, and the washing process is completed.  
      Meanwhile, the rinsing process of the general washing machine is performed with the same steps of the washing process as described above, except that, when the unbalance degree of the inner tub  8  is the acceptable degree, the dewatering process is immediately performed. At this time, in order to allow detergent-free rinsing water to be supplied into the inner tub, the detergent cannot be supplied to the detergent barrel  8 .  
      After the rinsing process as mentioned above, the dewatering process is performed such that water absorbed in the laundry can be extracted by centrifugal force, thereby allowing the laundry to be rapidly, naturally dried, and when the dewatering process is completed, the washing operation for the laundry is completed.  
      However, in the washing method of the general washing machine as described above, since the laundry is disentangled while the inner tub  8  is rotated at the low speed to generate the agitating force, a water stream for disentangling the laundry has a weak force, so that the laundry is not substantially moved. In other words, since the conventional washing method does not ensure effective laundry disentanglement, the disentangling step must be repeated several times, thereby increasing a washing time as well as energy consumption.  
      Additionally, if the laundry is not suitably disentangled in the inner tub, infinite repetition of the disentangling step may occur.  
     SUMMARY OF THE INVENTION  
      The present invention has been made to solve the above problems, and it is an object of the present invention to provide a washing method of a washing machine, which forms a water steam for sufficiently disentangling laundry in an inner tub.  
      In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a washing method of a washing machine, comprising the steps of: supplying water into the washing machine; forming an agitating water stream by rotating at least one of an inner tub and a pulsator to generate agitating force; and disentangling laundry by rotating the inner tub in one direction at a speed causing the laundry in the inner tub to be forced against an inner wall of the inner tub by centrifugal force while allowing the water to drop down into the inner tub after being raised in the washing machine.  
      At the step of supplying water, a detergent may be selectively input to the inner tub.  
      At the step of forming the agitating water stream, the laundry may be washed by water containing the detergent, or the laundry may be rinsed with detergent-free rinsing water.  
      At the step of forming the agitating water stream, the inner tub may be rotated integrally with the pulsator to generate the agitating force.  
      At the step of disentangling the laundry, the inner tub may be rotated at a speed of 80˜120 rpm.  
      At the step of disentangling the laundry, the inner tub may be rotated integrally with the pulsator in one direction.  
      The method may further comprise draining water after the step of disentangling the laundry.  
      The method may further comprise dewatering the laundry by rotating the inner tub in one direction at a speed causing water absorbed in the laundry to be extracted by centrifugal force, after draining water.  
      At the step of dewatering the laundry, a rotating speed of the inner tub may be higher than that of the inner tub at the step of disentangling the laundry.  
      The method may further comprise detecting an unbalance degree of the inner tub between the step of draining water and the step of dewatering the laundry, and the step of dewatering the laundry may be performed if the unbalance degree of the inner tub is an acceptable degree.  
      If the unbalance degree of the inner tub is deviated from the acceptable degree, the method may further comprise re-disentangling the laundry by rotating the inner tub in one direction at the same speed as that of the step of disentangling the laundry while being supplied with water, followed by draining water, and re-detecting the unbalance degree of the inner tub.  
      At the step of re-disentangling the laundry, the inner tub may be rotated together with the pulsator in one direction.  
      In accordance with another aspect of the present invention, a washing method of a washing machine is provided, comprising the steps of: supplying water into the washing machine; forming an agitating water stream by rotating at least one of an inner tub and a pulsator to generate agitating force; disentangling laundry by integrally rotating the inner tub and the pulsator in one direction at a speed causing the laundry in the inner tub to be forced against an inner wall of the inner tub by centrifugal force while allowing water to drop down into the inner tub after being raised in the washing machine; draining water; detecting an unbalance degree of the inner tub; and dewatering the laundry by rotating the inner tub in one direction at a speed causing water absorbed in the laundry to be extracted by centrifugal force, after draining water, if the unbalance degree is an acceptable degree.  
      After the step of supplying water, a detergent may be selectively input to the inner tub.  
      At the step of forming the agitating water stream, the laundry may be washed by water containing the detergent, or the laundry may be rinsed with detergent-fee rinsing water.  
      At the step of disentangling the laundry, a rotating speed of the inner tub may be lower than that of the inner tub at the steps of dewatering the laundry.  
      If the unbalance degree of the inner tub is deviated from the acceptable degree, the method may further comprise re-disentangling the laundry by draining water after the inner tub and the pulsator are rotated in one direction at the same speed as that of the step of disentangling the laundry while water is supplied to the inner tub, and re-detecting the unbalance degree of the inner tub.  
      In accordance with yet another aspect of the present invention, a washing method of a washing machine is provided, comprising the steps of: supplying water into the washing machine; forming an agitating water stream by rotating an inner tub and a pulsator at the same time at a relatively low speed to generate agitating force in order to allow laundry to be washed or rinsed; disentangling the laundry by integrally rotating the inner tub and the pulsator in one direction so as to generate an alpha-shaped water stream; draining water; detecting an unbalance degree of the inner tub; and dewatering the laundry by rotating the inner tub in one direction at a relatively high speed, if the unbalance degree is an acceptable degree.  
      At the step of disentangling the laundry, a rotating speed of the inner tub may be lower than that of the inner tub at the step of dewatering the laundry.  
      If the unbalance degree of the inner tub is deviated from the acceptable degree, the method may further comprise re-disentangling the laundry, and re-detecting the unbalance degree of the inner tub.  
      The step of re-disentangling the laundry may comprise re-supplying water; re-disentangling the laundry by rotating the inner tub and the pulsator in one direction at the same speed as that of the step of disentangling the laundry; and draining water.  
      With the washing method of the washing machine according to the invention, since the laundry is completely spread along the inner wall of the inner tub by the step of disentangling the laundry, the laundry can be highly effectively disentangled in the inner tub. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The foregoing and other objects and features 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 diagram illustrating the structure of a general washing machine;  
       FIG. 2  is a flow diagram illustrating a washing process of the general washing machine;  
       FIG. 3  is a flow diagram illustrating a washing process of a washing machine in accordance with one embodiment of the present invention;  
       FIG. 4  is a diagram illustrating the step of forming an agitating water stream of the washing method of the washing method in accordance with the present invention;  
       FIG. 5  is a diagram illustrating the step of forming an alpha-shaped water stream of the washing method of the washing machine in accordance with the present invention;  
       FIG. 6  is a flow diagram illustrating a rinsing process of the washing machine in accordance with the present invention; and  
       FIG. 7  is a flow diagram illustrating a rinsing process of a washing machine in accordance with another embodiment of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.  
      It should be noted that although various embodiments can be realized within the scope of the invention, most preferred embodiments of the invention will be described hereinafter. Meanwhile, since the structure of a washing machine is the same as that of the general washing machine, detailed description thereof will be omitted hereinafter.  
      A washing method of a washing machine according to one embodiment of the invention, in which a washing process, a rinsing process, and a dewatering process are sequentially performed, will be described as follows.  
       FIG. 1  is a diagram illustrating the structure of a general washing machine,  FIG. 3  is a flow diagram illustrating the washing process in the washing method of the invention,  FIG. 4  is a diagram illustrating the step of forming an agitating water stream in the washing method of the invention, and  FIG. 5  is a diagram illustrating the step of forming an alpha-shaped water stream of the washing method of the invention.  
      After laundry “m” is input to an inner tub  8 , and a door  1  is closed, a sequence for a washing operation is input through a controller  4  such that the washing process, the rinsing process, and the dewatering process are sequentially performed. Then, the washing machine is operated with the washing process as a first process of the washing operation.  
      In the washing process, first, water is supplied into the washing machine to a predetermined level of an inner tub according an amount of laundry through a water supply apparatus  10 . At this time, when detergent is contained in a detergent barrel  8 , the detergent can also be supplied into the washing machine together with the water since the detergent in the detergent barrel  8  is washed into an outer tub  6  by water (S 50 ).  
      When water is supplied to the washing machine to the predetermined level of the inner tub at the step of supplying water, at least one of the inner tub  8  and a pulsator  9  is rotated to generate agitating force by driving force of a motor  20 , as shown in  FIGS. 1, 3  and  4 .  
      The inner tub  8  and the pulsator  9  are directly connected to the motor  20 , and can be integrally rotated thereby. It is desirable that the motor  20  be rotated at a speed (for example, 110˜150 rpm) which can force the inner tub  8  and the pulsator  9  to be rotated such that a relatively strong agitating water stream R can be produced by the rotation of the inner tub  8  and the pulsator  9 .  
      When the inner tub  8  and the pulsator  9  are rotated to generate the agitating force as described above, contaminants stuck to the laundry m in the inner tub  8  are detached therefrom by means of interaction of the detergent and the agitating water stream R with the laundry. For reference, when the laundry is washed by means of the interaction of the detergent and the agitating water stream R with the laundry, it will be referred to as a washing step or the step of forming an agitating water stream (S 52 ).  
      Then, after the inner tub  8  and the pulsator  9  are rotated at a low speed for a predetermined time to generate the agitating force, the inner tub  8  and the pulsator  9  are stopped together with the motor  20 , as shown in  FIGS. 1, 2  and  3 , and the step of disentangling the laundry is performed such that the laundry m entangled during the washing step can be disentangled.  
      At the step of disentangling the laundry, the inner tub  8  is rotated in one direction at a speed which allows the laundry m within the inner tub  8  to be completely forced against an inner wall of the inner tub  8 .  
      Additionally, at this step, the inner tub  8  is rotated in one direction at a speed, that is, a speed of forming an alpha-shaped water stream α, which allows water to be dropped down into the inner tub  8  by means of a tub cover  5  provided at an upper end of the outer tub  6  after being raised along an outer wall of the inner tub  8  between the outer tub  6  and the inner tub  8  by centrifugal force.  
      At this time, water passes through the laundry in the inner tub  8  in a centrifugal direction.  
      At the step of disentangling the laundry as described above, the inner tub  8  may be rotated integrally with the pulsate  9 , and at this time, a rotating speed of the inner tub  8  and the pulsator  9  is preferably in the range of 80 to 120 rpm. It should be noted that, at the step of disentangling the laundry, the rotating speed of the inner tub  8  and the pulsator  9  can be deviated from the range of 80 to 120 rpm.  
      Meanwhile, at the step of disentangling the laundry, since the inner tub  8  is filled with water such that the laundry is sufficiently immersed in the water, even if the inner tub  8  and the pulsator  9  are rotated in one direction, vibration of the washing machine is not severe (S 54 ).  
      After finishing the step of disentangling the laundry, the inner tub  8  and the pulsator  9  are stopped, and contaminated water is drained to the outside by a draining device  12  (S 56 ).  
      After finishing the step of draining water using the draining device  12 , the step of detecting an unbalance degree of the inner tub  8  is performed in order to detect whether the laundry m is uniformly spread in the inner tub  8  by the step of disentangling the laundry.  
      The step of detecting the unbalance degree is performed using variance of load applied to the motor  20 , that is, variation in driving speed of the motor  20 , according to the unbalance degree of the inner tub  8  upon one rotation of the inner tub  8 .  
      That is, at the step of detecting the unbalance degree, after the motor  20  is driven so as to force the inner tub  8  to rotate at a relatively low speed, an unbalance degree U of the inner tub  8  is obtained through variation in the driving speed of the motor  20 , and is then compared with a predetermined unbalance reference U o .  
      At this time, the unbalance reference U o  is a minimum unbalance degree, which can cause severe vibration of the washing machine when the inner tub  9  is rotated at a high speed without being supplied with water. If the unbalance degree U of the inner tub  8  is equal to or greater than the unbalance reference U o , it is determined that the unbalance degree U of the inner tub  8  is deviated from an acceptable degree (S 58 ).  
      Then, the step of re-disentangling the laundry is performed such that the laundry m can be further sufficiently spread in the inner tub  8 .  
      The step of re-disentangling the laundry may comprise re-supplying water into the washing machine by the water supplying apparatus  10 , re-disentangling the laundry with the same method as that of the step of disentangling the laundry as described above, and draining water via the water draining device  12 .  
      The step of re-forming the agitating water stream may be performed between the step of re-supplying water and the step of re-disentangling the laundry, in which both the inner tub  8  and the outer tub  9  are rotated at a low speed to generate the agitating force. The step of re-forming the agitating water stream may be performed for a time shorter than or the same as that of the step of forming the agitating water stream or the step of washing the laundry as described above (S 57 ).  
      After the step of re-disentangling the laundry, the step of detecting an unbalance degree of the inner tub is performed again (S 58 ). The step of re-disentangling the laundry, and the step of re-detecting the unbalance degree are preferably repeated at least once until the unbalance degree of the inner tub  8  becomes the acceptable degree.  
      Meanwhile, when it is detected through the step of detecting the unbalance degree that the unbalance degree of the inner tub  8  is the acceptable degree, the inner tub  8  is rotated in one direction at a speed higher than those of the steps of washing the laundry and of disentangling the laundry. As a result, foreign substances such as detergent bubbles and lint are discharged together with water remaining in the outer tub  6  as well as water absorbed into the laundry in the inner tub  8 .  
      At this time, it is desirable that the step of dewatering during the washing process be performed for a shorter time than a process of dewatering the laundry as described below. The step of dewatering during the washing process will be referred to as a temporary dewatering step (S 60 ).  
      After the temporary dewatering step, the process of washing the laundry comprising the step of disentangling the laundry using the alpha-shaped water stream according to the invention is completed.  
      Meanwhile,  FIG. 1  is a diagram illustrating the general washing machine, and  FIG. 6  is a flow diagram illustrating a rinsing process of the washing machine according to the invention. The rinsing process of the washing machine according to the invention is performed, which comprises the same steps of the washing process having the step of disentangling the laundry using the alpha-shaped water as described above, except that detergent-free rinsing water is supplied into the washing machine, and that the temporary dewatering step is selectively performed.  
      The rinsing process of the invention comprises the steps of: supplying detergent-free rinsing water (S 80 ); rinsing laundry using an agitating water stream (S 82 ); disentangling the laundry using an alpha-shaped water stream (S 84 ); draining water to drain contaminated rinsing water (S 86 ); and detecting an unbalance degree of the inner tub (S 88 ), which are sequentially performed in the same sequence as that of the washing process as described above. Additionally, according to a result of the step of detecting the unbalance degree of the inner tub, the rinsing process of the invention further comprises the step of re-disentangling the laundry which is the same as that of the washing process described above (S 87 ).  
      After finishing the rinsing process, the dewatering process is performed, in which the inner tub  8  is rotated in one direction at a high speed such that the laundry m is dewatered by centrifugal force.  
      During the dewatering process, the pulsator  9  is rotated integrally with the inner tub  8 .  
      Particularly, unlike the temporary dewatering step during the washing process as described above, the dewatering process is performed in such a manner that the inner tub  8  is rotated for a long period at a high speed (for example, about 700 rpm), thereby allowing the laundry m to be dewatered (for example, to 50˜80% of water absorbed in the laundry) for natural dry of the laundry m.  
      After finishing the dewatering process as described above, the washing operation according to the washing method of the washing machine of the invention is completed.  
      Meanwhile, it should be noted that the respective processes of the washing method of the washing machine of the invention can be selectively performed by a user.  
      When the washing operation is finished without the dewatering process after the rinsing process having the step of disentangling the laundry using the alpha-shaped water stream of the invention, as described in  FIG. 7 , the rinsing process having the step of disentangling the laundry using the alpha-shaped water stream may comprise the steps of: supplying rinsing water as described above (S 100 ); rinsing laundry (S 102 ); disentangling the laundry (S 104 ); draining water (S 106 ); detecting an unbalance degree of the inner tub (S 108 ); re-disentangling the laundry (S 107 ); and temporary dewatering the laundry (S 110 ), which is the same as that of the washing process.  
      As apparent from the above description, with the washing method of the washing machine according to the invention, the inner tub  8  is rotated in one direction during the step of disentangling a laundry, so that the laundry is completely forced against an inner wall of the inner tub  8 , thereby enhancing the disentangling effect, compared with the effect when using the agitating water according to the prior art.  
      Additionally, with the washing method of the invention, the inner tub  8  is rotated in one direction so as to form an alpha-shaped water stream during the step of disentangling the laundry, so that the laundry is more actively moved therein than when the laundry is disentangled using the agitating water according to the prior art, and so that water centrifugally passes through the laundry after being raised in the outer tub, thereby enhancing washing and rinsing effect as well as the disentangling effect.  
      It should be understood that the embodiments and the accompanying drawings as described above have been described for illustrative purposes and the present invention is limited by the following claims. Further, those skilled in the art will appreciate that various modifications, additions and substitutions are allowed without departing from the scope and spirit of the invention as set forth in the accompanying claims.