Spin Drain Cycles for Reduction of Load Tangling in Abbreviated or No Central Column Top Load Laundry Washer

Abstract

In place of a static drain, a final tub spin interval during a wash cycle and/or rinse cycle of a laundry washing machine/process is continued at the time that the main drain of the free liquid in the wash tub is initiated. This spin may continue until completion of the drain and extraction. In one embodiment, the sequence includes a transition from a relatively slow speed spin of a rinse or wash agitation interval to a high speed extraction spin. Thus, the conventional transition from the rinse and/or wash cycle to a static drain is eliminated. In addition, the conventional transition from a static drain to a high-speed extraction spin drain is eliminated. Such a change in the operation sequence of the washer can help reduce tangling and/or balling of the wash load, especially in a washer having an abbreviated or no central column/agitator. Such a change can also reduce associated imbalance during the spin drain, which can benefit machines both with and without a central agitator.

1 . An automatic washing machine, comprising:
 a frame; and   a wash basin rotatably mounted within the frame, the wash basin having a bottom and sidewalls extending up from said bottom;   a drive system for selectively spinning said wash basin;   a drain system for automatically draining the wash basin of wash liquid therein; and   control means for controlling said drive system to selectively spin the wash basin and for controlling said drain system to selectively drain the wash basin of said wash liquid, said control means being configured to initiate a drain of free wash liquid in the wash basin while the wash basin is being spun by the drive system.   
   
   
       2 . An automatic washing machine according to  claim 1 , wherein the drain of the wash basin is initiated during a period of spinning of the wash basin and free liquid therein, continued from a spin interval of a wash cycle or rinse cycle of the washing machine. 
   
   
       3 . An automatic washing machine according to  claim 2 , wherein said spin interval is a final spin interval of said wash cycle or rinse cycle. 
   
   
       4 . An automatic washing machine according to  claim 1 , wherein said control means is further configured to continue to spin the wash basin to completion of the drain of free liquid from the wash basin. 
   
   
       5 . An automatic washing machine according to  claim 4 , wherein said control means is further configured to transition from a relatively slow speed spin at initiation of the drain of free liquid from the wash basin, directly into a relatively high speed extraction spin interval during which wash liquid absorbed within a wash load is extracted and drained from the wash basin. 
   
   
       6 . An automatic washing machine according to  claim 1 , wherein the wash basin lacks a central agitator or column rising substantially from the bottom of the wash basin. 
   
   
       7 . An automatic washing machine according to  claim 1 , wherein said rotatable wash basin has fixedly mounted thereon at least one wash/rinse action generating element. 
   
   
       8 . An automatic washing machine according to  claim 7 , wherein said at least one wash/rinse action generating element comprises a ramp structure. 
   
   
       9 . An automatic washing machine according to  claim 1 , wherein said control means is configured to carry out the drain of free liquid while a rotation speed of the wash basin is maintained which is sufficient to keep laundry load items within the wash basin segregated to the sides of the basin as the free liquid level drops. 
   
   
       10 . An automatic washing machine according to  claim 1 , wherein said control means is configured to cause said wash basin to alternately, successively, rotate in opposing directions during a wash or rinse agitation cycle, and initiation of the drain of free liquid from the wash basin takes place without interruption of the final spin of the tub during the rinse or wash agitation cycle. 
   
   
       11 . A method of washing a load of laundry using an automatic washing machine, comprising:
 placing a load of laundry within a wash basin rotatably mounted within a frame, said wash basin having a bottom and sidewalls extending up from said bottom;   dispensing wash liquid into said wash basin containing said load of laundry;   selectively spinning said wash basin, including said wash liquid and laundry; and   initiating a drain of free wash liquid from the wash basin while the wash basin is being spun.   
   
   
       12 . A method according to  claim 11 , wherein the drain of free wash liquid from the wash basin is initiated during a period of spinning of the wash basin and free liquid therein, continued from a spin interval of a wash cycle or rinse cycle of the washing machine. 
   
   
       13 . A method according to  claim 12 , wherein said spin interval is a final spin interval of said wash cycle or rinse cycle. 
   
   
       14 . A method according to  claim 11 , wherein said period of spinning of the wash basin continues to completion of the drain of free liquid from the wash basin. 
   
   
       15 . A method according to  claim 14 , further comprising transitioning from a relatively slow speed spin at initiation of the drain of free liquid from the wash basin, directly into a relatively high speed extraction spin interval during which wash liquid absorbed within the wash load is extracted and drained from the wash basin. 
   
   
       16 . A method according to  claim 11 , wherein the drain of free liquid is carried out while a rotation speed of the wash basin is maintained which is sufficient to keep the load of laundry within the wash basin segregated to the sides of the basin as the free liquid level drops. 
   
   
       17 . A method according to  claim 11 , further comprising causing said wash basin to alternately, successively, rotate in opposing directions during a wash or rinse agitation cycle, and wherein the initiation of the drain of free liquid from the wash basin takes place without interruption of the final spin of the tub during the rinse or wash agitation cycle. 
   
   
       19 . A method according to  claim 11 , wherein initiation of the drain of free wash liquid occurs when the wash basin is rotating at a speed sufficient to form a generally parabolic wash liquid profile within the wash basin, the laundry load has risen with the water parabola along the sidewalls of the basin, and due to the centrifugal force, the load remains distributed in a generally torroidal configuration against the sidewalls as the water level drops. 
   
   
       20 . A method according to  claim 19 , further comprising, after the free wash liquid has been substantially drained from the basin, causing the wash basin to continue to rotate so as to maintain the load distributed in said generally torroidal shape against the sidewalls of the basin, then ramping the rotation speed up to directly enter the high-speed spin extraction phase.