Washing machine

Abstract

The present invention relates to a washing machine comprising: a tub provided inside a cabinet and storing washing water therein; and a plurality of super-hydrophobic micro-protrusions formed on the inner surface of the tub to remove residual water within the tub. Accordingly, since the plurality of super-hydrophobic micro-protrusions are formed on the inner surface of the tub, the residual water remaining inside the tub can be cleanly removed using the lotus effect, thereby maintaining a clean state of the washing machine.

What is claimed is: 
     
         1 . A washing machine, comprising:
 a tub provided inside a cabinet to store wash water therein; and   a plurality of super-hydrophobic micro-protrusions formed on an inner surface of the tub to remove residual water in the tub.   
     
     
         2 . The washing machine of  claim 1 , wherein the plurality of super-hydrophobic micro-protrusions are injection molded by an injection mold together with the tub, and integrally formed on an inner surface of the tub. 
     
     
         3 . The washing machine of  claim 2 , wherein the tub comprises:
 a tub cover formed with an inlet port for putting washing objects therein on a front side of the tub to form a front portion of the tub when the tub is divided into the front portion and the rear portion along a circumferential surface; and   a tub body coupled to a rear end of the tub cover to form the rear portion of the tub.   
     
     
         4 . The washing machine of  claim 3 , wherein the plurality of super-hydrophobic micro-protrusions are formed on a front side in the tub cover and a rear side in the tub body. 
     
     
         5 . The washing machine of  claim 1 , wherein each of the plurality of super-hydrophobic micro-protrusions has an upper width thereof smaller than or equal to a lower width thereof. 
     
     
         6 . The washing machine of  claim 1 , wherein each of the plurality of super-hydrophobic micro-protrusions is formed in any one of a round shape, a triangular shape, and a rectangular shape. 
     
     
         7 . The washing machine of  claim 1 , wherein the plurality of super-hydrophobic micro-protrusions are symmetrically formed on both sides with respect to one directional center lines spaced apart in parallel from each other along an inner surface of the tub. 
     
     
         8 . The washing machine of  claim 1 , wherein the plurality of super-hydrophobic micro-protrusions are formed symmetrically on both sides with respect to first directional center lines spaced apart in parallel from each other along an inner surface of the tub and second directional center lines spaced apart in parallel from each other in a direction intersecting the first directional center line. 
     
     
         9 . The washing machine of  claim 8 , wherein the first directional center line and the second directional centerline are formed in a lattice shape. 
     
     
         10 . The washing machine of  claim 1 , wherein the plurality of super-hydrophobic micro-protrusions are formed on a circumferential surface in the tub. 
     
     
         11 . The washing machine of  claim 10 , wherein the plurality of super-hydrophobic micro-protrusions are protruded along a longitudinal direction of the tub in a direction in which an injection mold is separated to prevent an undercut of the injection mold after injection molding. 
     
     
         12 . The washing machine of  claim 10 , wherein the plurality of super-hydrophobic micro-protrusions are arranged to be spaced apart from each other in a circumferential direction of the tub. 
     
     
         13 . The washing machine of  claim 1 , wherein the plurality of super-hydrophobic micro-protrusions are symmetrically formed on both sides with respect to longitudinal center lines of a circumferential surface of the tub spaced apart in parallel from each other along the circumferential surface. 
     
     
         14 . The washing machine of  claim 10 , wherein the plurality of super-hydrophobic micro-protrusions are formed asymmetrically on both sides with respect to longitudinal center lines of the circumferential surface spaced apart in parallel from each other along the circumferential surface of the tub to allow residual water in the tub to flow in a circumferential direction. 
     
     
         15 . The washing machine of  claim 1 , further comprising:
 a sump formed on a bottom surface in the tub, and provided with a drain port for discharging wash water in the tub to the outside,   wherein the plurality of super-hydrophobic micro-protrusions are formed on a surface of the sump.   
     
     
         16 . The washing machine of  claim 15 , wherein the sump is recessed along the longitudinal direction of the tub toward a front side of the tub at a rear lower-end portion of the tub, and the plurality of super-hydrophobic micro-protrusions are protruded along a longitudinal direction of the sump in a direction in which the injection mold is separated to prevent an undercut of the injection mold after injection molding. 
     
     
         17 . The washing machine of  claim 15 , wherein the sump is formed at a lower position than a circumferential surface of the tub, and inclined downward toward a front side of the tub. 
     
     
         18 . The washing machine of  claim 15 , wherein the drain port is spaced apart from a longitudinal center line of the sump in one direction. 
     
     
         19 . The washing machine of  claim 15 , wherein the sump further comprises a residual water guide passage portion one side of which is communicated with the drain port, and spaced apart from a longitudinal center line of the sump to guide residual water in the sump to the drain port. 
     
     
         20 . The washing machine of  claim 19 , wherein the plurality of super-hydrophobic micro-protrusions are formed asymmetrically on both sides with respect to longitudinal center lines of the sump spaced apart in parallel from each other along the bottom surface of the sump to allow residual water in the sump to flow toward the residual water guide passage portion, and provided with a first inclined portion having a small slope on one side toward the residual water guide passage portion and a second inclined portion having a relatively large slope on another side toward a direction opposite to the residual water guide passage.