Patent Publication Number: US-2005132758-A1

Title: Device for circulating washing water in washing machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims the benefit of the Korean Application No. 10-2003-0093190 filed on Dec. 18, 2003, which is hereby incorporated by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to washing machines, and more particularly, to a washing water circulating device for pumping up water from a lower portion to an upper portion of a tub in a washing machine.  
      2. Background of the Related Art  
      The washing machine removes contaminants stuck to laundry by using action of detergent and water.  
      In general, there are agitator type, pulsator type, and drum type washing machines. The agitator type washing machine washes by rotating a washing rod standing at a central portion of a tub in left/right directions, and the pulsator type washing machine washes laundry by using a friction force between water circulation, caused by left/right direction rotation of a disc form of pulsator on a bottom of a washing tub, and the laundry. The drum type washing machine washes laundry by putting water, detergent, and the laundry into an inside of the drum having a plurality of tumbling ribs projected from an inside surface thereof, and rotating the drum at a low speed.  
      In the meantime, when the laundry is washed, by using one of above different types of washing machines, detergent is used, together with water. That is, the washing is performed after the detergent is introduced into the tub having the laundry and the water filled therein, manually or automatically.  
      However, in case powder detergent is introduced into the tub, though a portion of the detergent is dissolved in the water and enhances a washing capability, the other portion is not dissolved and inserted between strands of the laundry. The powder detergent inserted between the strands of laundry drops washing capability of the washing machine, and prolongs a washing time period.  
      Moreover, even after finishing the washing, a portion of the powder detergent remains in the laundry, and damages skin of the user.  
     SUMMARY OF THE INVENTION  
      Accordingly, the present invention is directed to a washing water circulating device in a washing machine that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.  
      An object of the present invention designed to solve the above problems lies in improving detergent dissolving capability of the washing machine for preventing powder detergent introduced into a tub from remaining on laundry.  
      Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.  
      To achieve these objects and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, the washing water circulating device in a washing machine includes a water circulating portion that pumps water from an inside of a tub to an outside of the tub and supplies water into the tub, and a flow passage control portion that keeps the pumped water circulating through the outside of the tub, or guided into the tub.  
      The water circulating portion preferably includes a water circulating passage having both ends in communication with the tub, and a water circulating pump connected to the water circulating passage.  
      The flow passage control portion preferably includes a bypass tube having both ends connected to a water circulating passage provided for a flow of the pumped water, and a flow passage switching portion provided to the water circulating passage, that guides the pumped water to the bypass tube to circulate on the outside of the tub only, or guides the pumped water to the bypass tube and then guides the pumped water to the tub.  
      The flow passage control portion preferably makes the pumped water keep circulating through the outside of the tub to dissolve the detergent.  
      In other aspect of the present invention, there is provided a washing water circulating device in a washing machine including a first tube connected to a tub, a water circulating pump connected to the first tube that pumps water from the tub, a second tube connected to the water circulating pump that supplies the pumped water to the tub, a bypass tube provided between the first tube and the second tube, and a control valve provided to the second tube that guides the pumped water to one of the second tube and the bypass tube.  
      In another aspect of the present invention, there is provided a washing machine including a cabinet having a door, a tub mounted in the cabinet that holds water therein, a drum rotatably mounted in an inside of the tub, a water supplying device that supplies detergent and water to the tub, and a washing water circulating device wherein the washing water circulating device includes a first tube connected to the tub, a water circulating pump connected to the first tube that pumps water from the tub, a second tube connected to the water circulating pump that supplies the pumped water to the tub, a bypass tube provided between the first tube and the second tube, and a control valve provided to the second tube that guides the pumped water to one of the second tube and the bypass tube.  
      The first tube is connected to a drain, or an under side of the tub.  
      The second tube preferably sprays the water pumped by the water circulating pump to an inside of the drum.  
      The control valve is provided to a connection portion of the second tube and the bypass tube, or between the connection portion and the tub.  
      In the meantime, preferably the control valve guides the pumped water to the bypass tube for a preset time period at an initial stage of washing when detergent is supplied to the tub. The control valve preferably guides the water to the second tube after a preset time period set from a starting of washing is completed. The water supply device may supply detergent and water to a space between the tub and the drum.  
      It is to be understood that both the foregoing description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention claimed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention.  
      In the drawings;  
       FIG. 1  illustrates a diagram of a drum type washing machine having a washing water circulating device of the present invention applied thereto;  
       FIG. 2A  illustrates a diagram of a position of a control valve and a water flow when the washing water circulating device of the present invention in  FIG. 1  dissolves detergent;  FIG. 2B  illustrates a diagram of a position of a control valve and a water flow when the washing water circulating device of the present invention in  FIG. 1  circulates water in a tub; and  
       FIG. 3  illustrates a diagram of a modification of the drum type washing machine shown in  FIG. 1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. In describing the embodiments, identical parts will be given the same names and reference symbols, and repetitive description of which will be omitted.  
       FIG. 1  illustrates a diagram of a drum type washing machine having a washing water circulating device of the present invention applied thereto. Though  FIG. 1  illustrates a drum type washing machine having a tub in a cabinet and a drum rotatably mounted on an inside of the tub, the washing machine of the present invention is not limited to the illustrated drum type washing machine, but is applicable to a pulsator type washing machine having upright tub and drum, or the like in the same fashion.  
      The washing machine of the present invention will be described in more detail with reference to the attached drawings. Referring to  FIG. 1 , there is an opening in a front surface of a cabinet  10  that forms an outer shape of the washing machine, and a door  15  rotatably mounted on the front surface of the cabinet  10  for opening/closing the opening.  
      There is a tub  20  arranged inside of the cabinet  10  horizontal to a floor. The tub  20  is elastically supported by springs (not shown) and dampers (not shown) within the inside space. The tub  20  has an opened front surface opposite to the opening of the cabinet  10 . The tub  20  has water supplied thereto and held therein.  
      There is a drum  30  rotatably mounted in an inside space of the tub  20 . For this, a motor  25  is mounted on an inside of the cabinet  10  for rotating the drum  30 .  FIG. 1  illustrates an embodiment in which a shaft of the motor  25  is directly connected to the drum  30 . In this case, the shaft passes through the tub  20 . However, though not shown, the motor  25  may rotate the drum  30  indirectly. In this case, the drum  30  and the motor  25  may be connected with a belt.  
      The drum  30  has a plurality of pass through holes (not shown), so that water flows from the tub  20  to the inside space of the drum  30  through the pass through holes, and vice versa. Though not shown, the drum  30  has a plurality of tumbling ribs (not shown) projected from an inside circumferential surface. The tumbling ribs lift/drop the laundry when the drum  30  rotates.  
      In the meantime, there is a water supplying device  40  in the washing machine for supplying detergent and water into the tub  20 . The water supplying device  40  includes a water supply hose  45  connected between a water supply source, such as faucet and the tub  20 , and a detergent box  41  provided to be in communication with the water supply hose  45 .  
      Therefore, in a state detergent is supplied to the detergent box  4   i , if water is supplied to the tub  20  through the water supply hose  45 , the detergent is supplied to the tub  20  together with water. The detergent box  41  may be designed to supply a proper amount of detergent to the water supply hose  45  or the tub  20 .  
      In the meantime, it is preferable that the water supply device  40  supplies the detergent and water between the tub  20  and the drum  30 , so that the water and detergent hit the drum  30 , which helps dissolve the detergent. Moreover, the powder detergent not dissolved yet flows down along an outside surface of the drum  30 , and is held on a bottom surface of the tub  20 , to prevent the powder detergent from being supplied to the laundry directly, and inserted between strands of laundry.  
      In the meantime, there is a drain  21  in a bottom of the tub  20 , having a drain pipe (not shown) connected thereto. The drain pipe has a drain pump (not shown) connected thereto for pumping and discharging water, introduced thereto from the tub  20  through the drain  21  and the drain pipe, to an outside of the cabinet. Of course, the drain pump has a drain hose (not shown) in communication with an outside of the washing machine. Therefore, upon putting the drain pump into operation, water is drained from the tub  20  to the outside of the cabinet  10  through the drain  21 , the drain pipe, the drain pump, and the drain hose.  
      In the meantime, the washing machine of the present invention further includes a washing water circulating device  100 . The washing water circulating device  100  pumps out water from the tub  20  and the water to the tub  20  again, for improving washing and rinsing performance of the washing machine. Moreover, the washing water circulating device  100  serves most of the detergent introduced into the tub  20  to dissolve quickly. The washing water circulating device  100  will be described in more detail.  
      The washing water circulating device  100  includes a water circulating portion and a flow passage control portion. The water circulating portion pumps water from the tub  20  to an outside of the tub  20 , and supplies the water to the tub  20  again. The flow passage control portion keeps circulating the water pumped to an outside of the tub  20  on an outside of the tub  20 , or guides to the tub  20 . The water circulating portion and the flow passage control portion will be described in more detail with reference to the attached drawings.  
      The water circulating portion includes a water circulating passage, and a circulating pump  130 . The water circulating passage has both ends in communication with the tub  20 , and the circulating pump  130  is connected to the circulating pump  130 .  
      Referring to  FIG. 1 , the circulating passage in communication with the tub  20  includes two tubes. One is a first tube  110  connected to the drain  21  of the tub  20 , or a bottom portion of the tub  20 , more specifically to an underside surface thereof, and the other one is a second tube  120  in communication with an upper portion of an inside of the tub  20 , substantially.  
      If the first tube  110  is connected to the drain  21  or the bottom portion of the tub  20 , the powder detergent deposited on a bottom surface of the tub  20  can be guided to an inside of the first tube  110 , easily.  
      In the meantime, referring to  FIGS. 2A and 2B , the first tube  110  and the second tube  120  are connected to the circulating pump  130 , respectively. The circulating pump  130  includes an impeller  135  for pumping water from the tub  20 , and a motor  131  connected to the impeller  135  with a shaft for rotating the impeller  135 .  
      This structure enables the water introduced into the first tube  110  by the circulating pump  130  to an inside of the tub  20  again by the second tube  120 . It is preferable that the second tube  120  sprays the water pumped by the circulating pump  130  into an inside of the drum  30 , to increase falling energy of the water, and to improve the washing performance and a detergent dissolving capability of the washing machine.  
      Next, the flow control portion includes a bypass tube  140  and a flow passage switching portion. The bypass tube  140  has both ends of the circulating passage through which the water pumped from the tub  20  flows. In more detail, one end of the bypass tube  140  is connected to the first tube  110 , and the other end of the bypass tube  140  is connected to the second tube  120 .  
      The flow passage switching portion is provided to the circulating passage, more specifically, to the second tube  120 , and the water pumped from the tub  20  by the circulating pump  130 , is guided to either one of the second tube  120  or the bypass tube  140 .  
      A control valve  150  is provided at the flow passage switching portion in the present invention. As shown in  FIG. 1 , the control valve  150  is provided to a connection portion of the second tube  120  and the bypass tube  140 , or, as shown in  FIG. 3 , at a point between the connection portion of the second tube  120  and the bypass tube  140  and the tub  20  of the second tube  120 .  
      If the control valve  150  is provided to the connection portion of the second tube  120  and the bypass tube  140 , the control valve  150  may be a three way valve.  
      In this case, as shown in  FIG. 2A , the control valve  150  closes the second tube  120 , and makes the bypass tube  140  and the circulating pump  130  in communication. Thus the pumped water is guided to the bypass tube  140 .  
      The water guided to the bypass tube  140  is guided to the bypass tube  140  again after circulating through the first tube  110  and the circulating pump  130 . Therefore, the water pumped by the circulating pump  130  is kept circulating on an outside of the tub  20 .  
      On the contrary, referring to  FIG. 2B , if the control valve  150  closes the bypass tube  140 , and makes the circulating pump  130  and the tub  20  in communication, the water pumped by the circulating pump  130  is guided to the tub  20  via the second tube  120 .  
      In the meantime, as shown in  FIG. 3  if the control valve  150  is provided between the tub  20  and the connection portion of the second tube  120  and the bypass tube  140 , an on/off valve is used for the control valve  150 .  
      In this case, if the control valve  150  closes, the water pumped by the circulating pump  130  can not pass through the second tube  120 , but is guided to the bypass tube  140 . The water guided to the bypass tube  140  is guided to the bypass tube  140  again through the first tube  110  and the circulating pump  130 . Therefore, the water pumped by the circulating pump  130  is kept circulating on an outside of the tub  20 .  
      On the contrary, if the control valve  150  is opened, as shown in  FIG. 2B , the water pumped by the circulating pump  130  passes through the second tube  120 , and is supplied to the tub  20 .  
      Thus, the washing water circulating device  100  of the present invention having the flow passage control portion either circulates the water pumped to an outside of the tub  20  only on an outside of the tub  20 , or is supplied to the tub, again.  
      Thus, because water from the tub  20  is circulated, most of the powder detergent introduced into the tub  20  can be dissolved within a short time period at an initial stage of the washing. That is, when the detergent is introduced into the tub  20 , if the water and detergent are kept circulating on an outside of the tub  20  after the water and detergent are pumped to the outside of the tub  20 , a large amount of the detergent is dissolved quickly by the impeller  135  and the friction force caused by water circulation.  
      Therefore, if the water is supplied from the washing water circulating device  100  to the tub  20  after the detergent is dissolved, not only the insertion of powder detergent between strands of the laundry, but also a washing time period can be reduced, and a washing capability can be improved.  
      A time period in which the washing water circulates in the washing water circulating device  100  is preset at a control portion in the washing machine. In this instance, the control portion may control the time period for circulating the water and the detergent on the outside of the tub  20  for dissolving the detergent according to an amount of the laundry and an amount of the detergent.  
      Also, the control portion may preset a time period for circulating the water and the detergent on the outside of the tub  20  for dissolving the detergent regardless of an amount of the laundry and an amount of the detergent.  
      Moreover, the control portion may control to repeat circulating the water and detergent on the outside of the tub  20  for a preset time period, and supplying into the tub  20 .  
      The operation of the washing machine having the washing machine circulating device  100  of the present invention will be described.  
      The door is opened, and the laundry is introduced into the drum  30 . The door  15  is closed, and the washing machine is put into operation to introduce external water into the detergent box  41  through the water supply hose  45 . The detergent in the detergent box  41  dissolves in the water supplied thereto, and the water having the detergent dissolved therein is supplied between the tub  20  and the drum  30  through the water supply hose  45 .  
      The water and detergent supplied between the tub  20  and the drum  30  slides along an outside circumferential surface of the drum  30 , and held on the bottom surface of the tub  20 . According to this, the direct contact of the detergent not yet dissolved with the laundry and insertion between the strands of the laundry can be prevented effectively.  
      At the initial stage of the washing when the water and detergent are supplied to the tub  20 , the water circulating pump  130  is operated. In this instance, as shown in  FIG. 2A , the control valve  150  guides the water passed through the first tube  110  and the circulating pump  130 , to the bypass tube  140 .  
      According to this, the water and detergent pumped from the tub  20  to the outside of the tub  20  by the circulating pump  130  circulates on the outside of the tub  20  for a preset time period, to dissolve the most of the detergent. In the meantime, at the initial stage of washing in which the water and detergent are supplied to the tub  20 , and the detergent is dissolved in the water, the drum  30  is rotated at a lower speed or stationary.  
      After a preset time is passed from the starting of the washing, as shown in  FIG. 2B , the water is guided to the tub  20  via the second tube  120 . Then, the water having the detergent dissolved therein passes through the second tube  120 , and is supplied to the tub  20 .  
      In the meantime, if a certain amount of water is supplied to the tub  20 , the motor  25  rotates the drum  30 . When the drum  30  rotates, the laundry is lifted by the tumbling ribs, and dropped. Therefore, by chemical reaction of the detergent, impact energy when the laundry drops by the tumbling ribs, and the water circulation occurred at the time of rotation of the drum  30 , contaminants are separated from the laundry, to perform the washing.  
      During the washing, the washing water circulating device  100  pumps water from the tub  20  and sprays into the tub  20  again. Friction and impact energy generated by the falling water when the water is sprayed into the tub  20  improves a washing capability of the washing machine.  
      After washing is performed for a preset time period by rotating the drum  30 , the drum  30  and the circulating pump  130  stop. Contaminated water from the washing is drained to an outside of the washing machine. During the draining the drain pump (not shown) is put into operation to discharge the contaminated water from the tub  20  to the outside of the washing machine through the drain hose (not shown).  
      After draining is finished, the drain pump stops, and water is supplied to the tub  20  newly through the water supply hose  45 , and the drum  30  rotates to carry out a rinsing process. During rinsing, as the drum  30  rotates, and the circulating pump  130  operates, the rinsing is carried out by a process similar to the washing process.  
      The laundry, washing of which is finished as the rinsing and drain are repeated, has its water extracted within a drum that spins at a high speed. If the washing machine is provided with a heater or blower, the laundry having water extracted therefrom is dried completely by using hot air.  
      Thus, the washing water circulating device of the present invention can dissolved most of detergent by keeping circulating the detergent and the water on an outside of the tub.  
      The supply of the water and the detergent from the detergent box to a space between the drum and the tub can prevent the powder detergent inserted between strands of the laundry.  
      Therefore, even after the washing is finished, it is possible to prevent the powder detergent remaining on the laundry even after finish of the washing, as well as damage to skin of the user due to the remained detergent.  
      Because the washing water circulating device makes the most of the detergent to be dissolved, washing capability of the washing machine is improved, and the washing time period is shortened. Particularly, a rinsing time period required for removing the detergent from the laundry can be shortened.  
      Moreover, the system is very simple, a performance of the washing machine can be improved at a low cost.  
      It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.