Drum type washing machine

Abstract

A drum type washing machine has axially-extending lifters arranged around an inner peripheral surface of a rotating tub which is upwardly inclined to allow easy laundry loading and unloading. The lifters each have a height gradually reducing to correspond to the inclination angle of the rotating tub from a rear end of the rotating tub to a front end thereof. Each lifter has, at its top portion, a wave-shaped structure including crests and valleys alternately arranged at a certain pitch. Each of the crests and valleys has water spray holes. The lifter includes at least one partition plate which divides the interior of the lifter into at least two chambers. Accordingly, wash water raised by each lifter is uniformly sprayed throughout the length of the lifter.

1 . A drum type washing machine comprising: 
 a housing;    a rotating tub rotatably positioned in the housing and upwardly inclined toward a front wall of the housing at an inclination angle; and    at least one lifter arranged on an inner peripheral surface of the rotating tub, the lifter extending from the inner peripheral surface of the rotating tub so that a top portion of the lifter is horizontal with respect to the housing when the lifter is positioned at a lowest level of the rotating tub.    
   
   
       2 . The drum type washing machine according to  claim 1 , wherein the lifter has a length extending from a rear end of the rotating tub to a front end thereof.  
   
   
       3 . The drum type washing machine according to  claim 1 , wherein the lifter includes a plurality of water spray holes for downwardly spraying wash water raised by the lifter at the top portion of the lifter.  
   
   
       4 . The drum type washing machine according to  claim 1 , wherein the inclination angle of the rotating tub is substantially between 5° and 15°.  
   
   
       5 . The drum type washing machine according to  claim 4 , wherein a height of the lifter gradually reduces as the lifter extends from a rear end of the rotating tub to a front end thereof, and 
 wherein the top portion of the lifter has an angle equal to the inclination angle of the rotating tub with respect to a bottom portion of the lifter.    
   
   
       6 . A drum type washing machine comprising: 
 a housing;    a rotating tub rotatably positioned in the housing and upwardly inclined toward a front wall of the housing at an inclination angle; and    at least one lifter arranged axially along an inner peripheral surface of the rotating tub, the lifter having a height which gradually reduces as the lifter extends from a rear end of the rotating tub to a front end thereof so that a top portion of the lifter has an angle equal to the inclination angle of the rotating tub with respect to a bottom portion of the lifter.    
   
   
       7 . The drum type washing machine according to  claim 6 , wherein the inclination angle of the rotating tub is substantially between 5° and 15°.  
   
   
       8 . The drum type washing machine according to  6 , wherein the top portion of the lifter has a wave-shaped structure including a plurality of crests and a plurality of valleys alternately arranged at a particular pitch, and each of the crests and valleys has a plurality of water spray holes which downwardly spray wash water raised by the lifter.  
   
   
       9 . The drum type washing machine according to  claim 8 , wherein the water spray holes are longitudinally arranged in a plurality of rows, and corresponding water spray holes in respective rows are laterally aligned.  
   
   
       10 . The drum type washing machine according to  claim 6 , wherein the lifter includes in an interior of the lifter a plurality of partition plates which divide the interior of the lifter into a plurality of chambers.  
   
   
       11 . The drum type washing machine according to  claim 10 , wherein each partition plate is inclined toward a front end of the lifter such that an upper end of the partition plate is closer to a front end of the lifter than a lower end of the partition plate.  
   
   
       12 . The drum type washing machine according to  claim 10 , wherein the partition plates each have different inclination angles, respectively.  
   
   
       13 . The drum type washing machine according to  claim 10 , wherein the partition plates are arranged at different spaces, respectively.  
   
   
       14 . A drum type washing machine comprising: 
 a housing;    a rotating tub rotatably positioned in the housing and upwardly inclined toward a front wall of the housing an inclination angle; and    at least one lifter arranged on an inner peripheral surface of the rotating tub, the lifter including at a top portion thereof a plurality of grooves and a plurality of protrusions.    
   
   
       15 . The drum type washing machine according to  claim 14 , wherein the top portion of the lifter has a wave-shaped structure including a plurality of crests corresponding to the protrusions and a plurality of valleys corresponding to the grooves, the crests and protrusions being alternately arranged at a particular pitch, and each of the crests and protrusions has a plurality of water spray holes which downwardly spray wash water raised by the lifter.  
   
   
       16 . A drum type washing machine comprising: 
 a housing;    a rotating tub rotatably positioned in the housing and upwardly inclined toward a front wall of the housing at an inclination angle; and    at least one lifter arranged on an inner peripheral surface of the rotating tub, the lifter including, in an interior thereof, at least one partition plate which divides the interior of the lifter into at least two chambers.    
   
   
       17 . The drum type washing machine according to  claim 16 , wherein the lifter has, at a front end thereof, a height smaller than a rear end of the lifter, and the partition plates are arranged such that the chambers each have a same capacity.  
   
   
       18 . The drum type washing machine according to  claim 1 , further comprising: 
 another lifter,    wherein the lifters are positioned around the rotating tub such that the lifters are circumferentially spaced uniformly apart from one another.    
   
   
       19 . The drum type washing machine according to  claim 1 , wherein a first surface of the at least one lifter has a constant width, the first surface being closest to a center of the rotating tub.  
   
   
       20 . The drum type washing machine according to  claim 1 , wherein each lifter includes a hollow structure which receives wash water, the hollow structure having a plurality of openings which are open in a direction extending from a center of the rotating tub.  
   
   
       21 . The drum type washing machine according to  claim 1 , wherein the lifter includes a plurality of water spray holes at opposite side portions of the lifter.  
   
   
       22 . The drum type washing machine according to  claim 1 , further comprising: 
 at least one pair of bosses formed integrally with the lifter, the bosses extending from a first face of the lifter closest to a center of the rotating tub,    wherein each boss includes a threaded coupling hole at an end of the each boss farthest from the first face of the lifter.    
   
   
       23 . The drum type washing machine according to  claim 22 , wherein the lifter is attached to the rotating tub via at least one threaded coupling screw threaded through a coupling hole positioned on an exterior portion of the rotating tub.  
   
   
       24 . The drum type washing machine according to  claim 10 , wherein the chambers have substantially equal volumes.