Patent Publication Number: US-11028516-B2

Title: Washing machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a National Stage of International Application No. PCT/KR2017/007419 filed Jul. 11, 2017, which claims the benefit of Korean Patent Application No. 10-2016-0088041 filed Jul. 12, 2016 and Korean Patent Application No. 10-2017-0082273 filed Jun. 29, 2017, the disclosures of which are fully incorporated herein by reference into the present disclosure as if fully set forth herein. 
     TECHNICAL FIELD 
     Apparatuses consistent with the present disclosure relate to a washing machine including a washing tub capable of improving a washing effect of the laundry. 
     BACKGROUND 
     In general, a washing machine is divided into a pulsator type washing machine and a drum type washing machine depending on a washing manner, and both of the pulsator type washing machine and the drum type washing machine include a water tub and a washing tub. 
     In the pulsator type washing machine, a driving shaft of the washing tub in which washing is performed is provided to be perpendicular to the ground. A pulsator generating a flow of washing water is installed at a lower portion of the washing tub. In the pulsator type washing machine, the pulsator agitates the laundry and the washing water injected into the washing tub together to remove dirty from the laundry, while the washing tub and the pulsator being rotated by a motor in a state in which the laundry and the washing water are injected into the washing tub. 
     In the drum type washing machine, washing is performed by head drop. A lifter for lifting the laundry is disposed in the washing tub. 
     In the pulsator type washing machine and the drum type washing machine, dehydrating holes allowing water of the water tub to be introduced into the washing tub and allowing the water of the washing tub to be drained from the washing tub at the time of drainage or dehydration are provided in a circumferential portion of the washing tub. 
     In the related art, the dehydrating holes are arranged in an inner surface of the washing tub that is flat. In this case, friction between the inner surface of the washing tub and the laundry is not large, such that there is a limitation in improving a washing effect by the friction. 
     In addition, in the drum type washing machine according to the related art, a case in which the laundry is gathered toward an inlet (front) in a washing or dehydrating process occurs, and a case in which the laundry is gathered toward the inlet is sandwiched and damaged in a diaphragm connecting a body and the water tub to each other or between a door and the inlet occurs. 
     SUMMARY 
     The present disclosure provides a washing machine capable of improving a washing effect and dehydration efficiency. 
     The present disclosure also provides a washing machine capable of increasing a dehydration ratio by preventing a dehydration bottleneck phenomenon. 
     The present disclosure also provides a washing machine in which rigidity of a washing tub may be increased by continuously providing pattern sections on a surface of the washing tub. 
     The present disclosure also provides a washing machine capable of preventing the laundry from being gathered toward the front of a washing tub. 
     According to an aspect of the present disclosure, a washing machine includes: a body; a washing tub configured to be rotatably provided in the body, accommodate a laundry therein, and have a cylindrical shape; a plurality of recessed portions configured to be formed in an inner circumferential surface of the washing tub and be arranged in the plural in a circumferential direction of the washing tub to form a pattern; and first dehydrating holes configured to be formed in the respective recessed portions, wherein the respective recessed portions are formed in a length direction of the washing tub. 
     The recessed portions may be formed in a direction parallel with a driving shaft driving the washing tub. 
     The may include a first pattern section and a second pattern section spaced apart from each other and arranged in a direction of the driving shaft, and the washing machine may further include at least one second dehydrating hole configured to be formed between the first pattern section and the second pattern section. 
     The first dehydrating holes may be formed at both end portions of the recessed portion, respectively. 
     The recessed portion may be recessed from the inner circumferential surface of the washing tub toward the outside of the washing tub, and include a first inclined surface inclined downwardly in the circumferential direction of the washing tub and a second inclined surface connected to the first inclined surface and inclined upwardly in the circumferential direction of the washing tub. 
     The first dehydrating holes may be formed in a contact portion between the first inclined surface and the second inclined surface. 
     The recessed portion may include a connecting surface flatly connecting the first inclined surface and the second inclined surface to each other. 
     The first dehydrating holes may be formed in the connecting surface. 
     The recessed portion may include a guide groove formed in the connecting surface, the first dehydrating hole may be positioned in the guide groove, and the guide groove may have a shape inclined toward the first dehydrating hole. 
     The recessed portions may be arranged in a direction inclined with respect to the driving shaft driving the washing tub. 
     According to another aspect of the present disclosure, a washing machine includes: a body configured to have an inlet formed in a front surface thereof; a washing tub configured to be rotatably disposed in the body, accommodate a laundry injected through the inlet therein, and have a cylindrical shape; and a plurality of protruding portions configured to protrude from an inner circumferential surface of the washing tub toward an inner portion of the washing tub to form a pattern, wherein at least part of the respective protruding portions are curved in a helix direction from a portion adjacent to the inlet in a direction that becomes distant from the inlet. 
     The washing tub may be configured to rotate in a counterclockwise direction at the time of performing dehydration, and the at least part of the protruding portion may be curved in a right handed screw direction. 
     The protruding portion may include a front end portion adjacent to the inlet, a central portion connected to the front end portion, and a rear end portion connected to the central portion, the central portion may be curved in the right handed screw direction, and the front end portion and the rear end portion may be parallel with a shaft of the washing tub. 
     The protruding portion may include a plurality of recessed portions formed in a length direction of the protruding portion. 
     The recessed portion may have an oval shape extended in the length direction of the protruding portion. 
     The protruding portion may include at least one first dehydrating hole formed in the recessed portion. 
     The protruding portion may include at least one second dehydrating hole formed between the plurality of recessed portions. 
     The plurality of protruding portions may be disposed in parallel with each other in a circumferential direction of the washing tub. 
     The washing tub may include at least one third dehydrating hole formed between the plurality of protruding portions. 
     The protruding portion may have a helix shape extended from a front end of the washing tub toward a rear end of the washing tub in a direction opposed to a rotation direction of the washing tub. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view illustrating a washing machine according to an exemplary embodiment of the present disclosure; 
         FIG. 2  is an exploded perspective view illustrating a washing tub according to an exemplary embodiment of the present disclosure; 
         FIG. 3  is a plan view illustrating a state in which a washing tub according to an exemplary embodiment of the present disclosure is unrolled; 
         FIG. 4  is a cross-sectional view taken along line A-A′ of  FIG. 3 ; 
         FIG. 5  is a plan view illustrating a state in which a washing tub according to another exemplary embodiment of the present disclosure is unrolled; 
         FIG. 6  is a cross-sectional view taken along line B-B′ of  FIG. 5 ; 
         FIG. 7  is a plan view illustrating a state in which a washing tub according to still another exemplary embodiment of the present disclosure is unrolled; 
         FIG. 8  is a cross-sectional view taken along line C-C′ of  FIG. 7 ; 
         FIG. 9  is a plan view illustrating a state in which a washing tub according to yet still another exemplary embodiment of the present disclosure is unrolled; 
         FIG. 10  is a cross-sectional view taken along line D-D′ of  FIG. 9 ; 
         FIG. 11  is a cross-sectional view illustrating a washing machine according to another exemplary embodiment of the present disclosure; 
         FIG. 12  is a perspective view of a washing tub illustrated in  FIG. 11  when viewed from the front; 
         FIG. 13  is an exploded view of the washing tub illustrated in  FIG. 12 ; 
         FIG. 14  is an enlarged view of a protruding portion illustrated in  FIG. 13 ; 
         FIG. 15  is a partially enlarged perspective view of the washing tub illustrated in  FIG. 12 ; 
         FIG. 16  is a cross-sectional view taken along line E-E of the washing tub illustrated in  FIG. 15 ; 
         FIG. 17  is a perspective view of a washing tub according to yet still another exemplary embodiment of the present disclosure when viewed from the front; and 
         FIG. 18  is an exploded view of the washing tub illustrated in  FIG. 17 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to  FIGS. 1 through 18 . Exemplary embodiments to be described below will be described on the basis of exemplary embodiments most appropriate for understanding technical features of the present disclosure, and these exemplary embodiments do not limit the technical features of the present disclosure, but exemplify that the present disclosure may be implemented like these exemplary embodiments. 
     Therefore, the present disclosure may be variously modified without departing from the technical scope of the present disclosure through exemplary embodiments to be described below, and these modifications will be to fall within the technical scope of the present disclosure. In addition, to assist in the understanding of exemplary embodiments to be described below, components performing the same operations and related components in the respective exemplary embodiments will be denoted by the same or similar reference numerals throughout the accompanying drawings. 
     A drum washing machine will hereinafter be described by way of example, but the present disclosure is not limited thereto. That is, a configuration of a washing tub according to the present disclosure may also be applied to a top load-type automatic washing machine. 
       FIG. 1  is a cross-sectional view illustrating a washing machine according to an exemplary embodiment of the present disclosure, and  FIG. 2  is an exploded perspective view illustrating a washing tub according to an exemplary embodiment of the present disclosure. 
     Referring to  FIGS. 1 and 2 , the washing machine according to an exemplary embodiment of the present disclosure includes a body  10  having a front surface in which an inlet  11  for injecting the laundry is formed, a water tub  20  installed in the body  10  and storing washing water therein, and a washing tub  30  rotatably provided in the water tub  20  and accommodating the laundry therein. In addition, the washing machine includes a door  12  opening or closing the inlet  11  of the body  10 . 
     The water tub  20  is installed to be inclined at an predetermined angle with respect to an installation surface of the washing machine  1  so that a front surface portion  20   a  thereof in which an inlet is formed is positioned to be higher than that of a rear surface portion  20   b  thereof, and the washing tub  30  disposed in the water tub  20  is also installed to be inclined in the same form as that of the water tub  20 . However, the water tub and the washing tub are not limited thereto, but may also be installed not to be inclined. 
     The washing tub  30  is rotatably supported by a driving shaft  13  coupled to a rear surface portion  30   a  thereof and penetrating through the rear surface portion  20   b  of the water tub  20 . In addition, a driving motor  14  rotating the driving shaft  13  is installed outside the rear surface portion  20   b  of the water tub  20 . The driving motor  14  rotates the driving shaft  13 , such that the washing tub  30  disposed in the water tub  20  may rotate. The driving motor  14  rotates the washing tub  30  at a low speed at the time of performing washing, and rotates the washing tub  30  at a high speed in one direction at the time of performing dehydration. 
     A detergent supplying device  15  for supplying a detergent to an inner portion of the water tub  20  and a water supplying device  16  for supplying washing water to the inner portion of the water tub  20  are installed above the water tub  20 . The detergent supplying device  15  is installed at the front surface portion of the body  10 . The water supplying device  16  includes a first water supplying pipe  16   b  connecting between an external water supplying pipe  16   a  and the detergent supplying device  15 , a second water supplying pipe  16   c  connecting the detergent supplying device  15  and the water tub  20 , and a water supplying control valve  16   d  installed on the first water supplying pipe  16   b  and controlling water supplying. This is to allow the water supplied to the inner portion of the water tub  20  to pass through the detergent supplying device  15  to allow the detergent to be supplied together with the water to the water tub  20 . 
     A heater  17  heating the washing water of the water tub  20  is installed at a lower portion of an inner side of the water tub  20 . A heater accommodating portion  20   c  protruding downwardly is provided at a lower portion of the water tub  20  to install the heater  17 . This is to allow the washing water to be collected in the heater accommodating portion  20   c  while allowing the heater  17  to be accommodated in the heater accommodating portion  20   c.    
     A water draining device  50  for draining the washing water of the water tub  20  and a washing water circulating device  60  for supplying the washing water in the water tub  20  into the washing tub  30  are installed below outside of the water tub  20 . The water draining device  50  includes a first water draining pipe  52  connected to a drainage hole  51  installed at the lower portion of the water tub  20 , a water draining pump  53  installed on the first water draining pipe  52 , and a second water draining pipe  54  connected to an outlet of the water draining pump  53 . 
     The washing water circulating device  60  includes a flow path switching valve  61  installed on the second water draining pipe  54  connected to the outlet of the water draining pump  53 , a washing water circulating pipe  62  extended from the flow path switching valve  61  to an inlet  31  of the washing tub  30 , and a spraying nozzle  63  installed at an outlet of the washing water circulating pipe  62 . The flow path switching valve  61  may switch a flow path so that the washing water of the outlet of the water draining pump  53  is drained to the outside or flows to the washing water circulating pipe  62 . 
     The flow path switching valve  61  may be a general electromotive three-way valve. This is to allow the washing water in the water tub  20  to be sprayed to an inner portion of the washing tub  30  through the first water draining pipe  52  and the washing water circulating pipe  62  when the water draining pump  53  is operated in a state in which the flow path switching valve  61  is operated so that the washing water flows to the washing water circulating pipe  62 . When the water draining pump  53  is operated in a state in which the flow path switching valve  61  is operated so that the washing water flows to the second water draining pipe  54  guiding the washing water to the outside, the washing water of the water tub  20  is drained. 
     The washing tub  30  may have a cylindrical shape, and includes the rear surface portion  30   a  coupled to the driving shaft  13 , a front surface portion  30   b  in which the inlet  31  is formed, and a circumferential portion  30   c  having both ends each coupled to the front surface portion  30   b  and the rear surface portion  30   a  and having a cylindrical shape. A plurality of lifters  33  lifting and dropping the laundry in the washing tub  30  when the washing tub  30  rotates are installed on an inner surface of the circumferential portion  30   c  of the washing tub  30 , and a plurality of agitating protrusion  32  for improving washing force are formed on an inner surface of the rear surface portion  30   a  of the washing tub  30 . In addition, a pattern  40  including one or more recessed portions  42  and one or more dehydrating holes  43  are arranged on an inner surface of the washing tub  30 . 
     The inner surface of the circumferential portion  30   c  of the washing tub  30  configures an inner circumferential surface of the washing tub  30 . 
       FIG. 3  is a plan view illustrating a state in which a washing tub according to an exemplary embodiment of the present disclosure is unrolled, and  FIG. 4  is a cross-sectional view taken along line A-A′ of  FIG. 3 . 
     Referring to  FIGS. 3 and 4 , at least one pattern  40  may be provided at an inner side of the washing tub  30  according to an exemplary embodiment of the present disclosure. Hereinafter, one pattern  40  will be mainly described, but an exemplary embodiment of a case in which a plurality of patterns  40  are provided will be described below. 
     The pattern  40  may include a plurality of recessed portions  42  formed in a length direction of the washing tub  30  in the inner circumferential surface of the washing tub  30 . That is, the plurality of recessed portions  42  may be formed in the inner circumferential surface of the washing tub  30 , and be arranged in the plural in a circumferential direction of the washing tub  30  to form the pattern  40 . In addition, the respective recessed portions  42  are formed in the length direction of the washing tub  30 . 
     The recessed portions  42  are extended from the front surface portion  30   b  in which the inlet  31  is formed to the rear surface portion  30   a  coupled to the driving shaft  13 , and the washing tub  30  may include the recessed portions  42  and first dehydrating holes  43  formed in the recessed portions  42 . The recessed portions  42  may have a length direction parallel with the driving shaft  13  driving the washing tub  30 . In addition, the recessed portions  42  may be arranged in the plural in the circumferential direction of the washing tub  30 . 
     As an example, the recessed portions  42  are recessed from the inner circumferential surface of the washing tub  30  toward the outside of the washing tub  30 . In addition, the recessed portion  42  may be formed by a first inclined surface  421  inclined downwardly in the circumferential direction of the washing tub  30  and a second inclined surface  422  connected to the first inclined surface  421  and inclined upwardly in the circumferential direction of the washing tub  30 . The first dehydrating holes  43  may be positioned at a contact portion at which the first inclined surface  421  and the second inclined surface  422  are connected to each other, and may be spaced apart from each other by the same interval and be provided in the plural, in the length direction of the recessed portion  42 . 
     A third inclined surface  423 , which has a shape corresponding to that of the first inclined surface  421 , may be connected to the second inclined surface  422 , and a fourth inclined surface  424 , which has a shape corresponding to that of the second inclined surface  422 , may be connected to the third inclined surface  423 . That is, the recessed portions  42  may be continuously arranged in the circumferential direction of the washing tub  30 . 
     The contact portion at which the second inclined surface  422  and the third inclined surface  423  are connected to each other may be defined as a protruding portion  41 , and the protruding portion  41  may have a triangular shape. The protruding portion  41  may have a predetermined height h 1  in relation to a bottom surface (or an outer circumferential surface) of the washing tub  30 . It is effective in improving a moisture content ((weight after washing−weight before washing)/weight before washing*100(%)) that the height of the protruding portion  41  satisfies at least 2 mm or more. 
     In addition, a linear distance d 1  between the second inclined surface  422  and the third inclined surface  423  may have 20 mm or more. In the case in which the linear distance d 1  is less than 20 mm, a moisture content improving effect is slight, while in the case in which the linear distance d 1  is 20 mm or more, a moisture content improving effect may be improved by about 3% or more. 
     In addition, frictional force between the laundry and the washing tub  30  may be increased through the pattern  40  including the protruding portions  41  having the triangular shape to improve a flow of the washing water, resulting in an increase in washing force. 
       FIG. 5  is a plan view illustrating a state in which a washing tub according to another exemplary embodiment of the present disclosure is unrolled, and  FIG. 6  is a cross-sectional view taken along line B-B′ of  FIG. 5 . Hereinafter, contents different from those of the washing tub according to the exemplary embodiment of the present disclosure described with reference to  FIGS. 1 to 4  will be mainly described, and contents for which a description is omitted may be replaced by the abovementioned contents. 
     Referring to  FIGS. 5 and 6 , at least one pattern  40   a  may be provided at an inner side of the washing tub  30  according to another exemplary embodiment of the present disclosure. 
     The pattern  40   a  according to another exemplary embodiment of the present disclosure may include recessed portions  42   a  extended from the front surface portion  30   b  in which the inlet  31  is formed to the rear surface portion  30   a  coupled to the driving shaft  13  and first dehydrating holes  43   a  formed in the recessed portions  42   a . The recessed portions  42  may be arranged in a direction inclined with respect to the driving shaft  13  driving the washing tub  30 . In addition, the recessed portions  42  may be spaced apart from each other and be formed in parallel with each other, in the circumferential direction of the washing tub  30 . The first dehydrating holes  43   a  may be positioned in the recessed portions  42   a . Protruding portions  41   a  may be provided between the recessed portions  42   a , and cross sections of the protruding portions  41   a  may have a triangular shape. 
       FIG. 7  is a plan view illustrating a state in which a washing tub according to still another exemplary embodiment of the present disclosure is unrolled, and  FIG. 8  is a cross-sectional view taken along line C-C′ of  FIG. 7 . 
     Referring to  FIGS. 7 and 8 , at least one pattern  40   b  may be provided at an inner side of the washing tub  30  according to still another exemplary embodiment of the present disclosure. 
     The pattern  40   b  according to still another exemplary embodiment of the present disclosure may include recessed portions  42   b  extended from the front surface portion  30   b  in which the inlet  31  is formed to the rear surface portion  30   a  coupled to the driving shaft  13  and dehydrating holes  43   b  formed in the recessed portions  42   b . The recessed portions  42   b  may have a length direction parallel with the driving shaft  13  driving the washing tub  30 . In addition, the recessed portions  42  may be formed in the plural in parallel with each other in the circumferential direction of the washing tub  30 . 
     As an example, the recessed portions  42   b  may have a length less than ½ of lengths of the front surface portion and the rear surface portion of the washing tub  30 , and in the case in which the recessed portions  42   b  have the length less than ½ of the lengths of the front surface portion and the rear surface portion of the washing tub  30 , the recessed portions  42   b  may be spaced apart from each other and be arranged in the plural, in a direction of the driving shaft  13 . 
     As an example, referring to  FIG. 7 , the recessed portions  42   b  may be spaced apart from each other and be arranged as four rows, in the direction of the driving shaft  13 . Therefore, the pattern  40   b  may include a plurality of pattern sections. As an example, as illustrated in  FIG. 7 , the pattern  40   b  may include first to fourth pattern sections  40   ba ,  40   bb ,  40   bc , and  40   bd  in the direction of the driving shaft  13 . As described above, the respective recessed portions  42   b  are provided with the first dehydrating holes  43   b . In addition, the first dehydrating holes  43   b  may be each formed at both end portions of the recessed portion  42   b , and one or more first dehydrating holes  42   b  may be additionally provided at the same interval between the first dehydrating holes  42   b  each positioned at both end portions of the recessed portion  42   b.    
     As an example, a first dehydrating hole  43   b  formed in the first pattern section  40   ba  and a first dehydrating hole  43   b  formed in the second pattern section  40   bb , positioned to be closest to the first dehydrating hole  43   b  formed in the first pattern section  40   ba  may be positioned to be spaced apart from each other by a linear distance d 2  of 10 mm or more. In addition, first dehydrating holes  43   b  formed in the second pattern section  40   bb  and the third pattern section  40   bc  and first dehydrating holes  43   b  formed in the third pattern section  40   bc  and the fourth pattern section  40   bd  may be positioned to be spaced apart from each other by linear distances d 2  of 10 mm or more, respectively. The respective spaced linear distances d 2  between the first dehydrating holes  43   b  provided in the respective pattern sections  40   ba ,  40   bb ,  40   bc , and  40   bd  may be the same as each other. This is to improve workability of the washing tub  30  and maintain strength of the washing tub  30 . 
     In addition, separate second dehydrating holes  46   b  may be formed between the respective pattern sections  40   ba ,  40   bb ,  40   bc , and  40   bd . The separate second dehydrating holes  46   b  may be formed between the respective pattern sections  40   ba ,  40   bb ,  40   bc , and  40   bd  to prevent a dehydration bottleneck phenomenon occurring since dehydration is concentrated on the first dehydrating holes  43   b  of a predetermined pattern, resulting in an increase in a dehydration ratio. 
       FIG. 9  is a plan view illustrating a state in which a washing tub according to yet still another exemplary embodiment of the present disclosure is unrolled, and  FIG. 10  is a cross-sectional view taken along line D-D′ of  FIG. 9 . Hereinafter, contents different from those of the washing tub described with reference to  FIGS. 7 and 8  will be mainly described, and contents for which a description is omitted may be replaced by the abovementioned contents. 
     At least one pattern  40   c  may be provided at an inner side of the washing tub  30 . 
     Various accessories may be coupled to the inner side of the washing tub  30 . Examples of the accessories may include the lifter  33  and a guide filter. The lifter  33  may be mainly used in a drum washing machine to smoothly move the laundry, and the guide filter may be mainly used in an automatic washing machine. Portions of the washing tub  30  to which these accessories are coupled are defined as coupled portions  48   c.    
     The respective patterns  40   c  positioned at the inner side of the washing tub  30  may be positioned with the coupled portions  48  put as boundaries therebetween. That is, in the case in which the number of coupled portions  48   c  is one, two patterns  40   c  may be provided, and in the case in which the number of coupled portions  48   c  is two, three patterns  40   c  may be provided. 
     The pattern  40   c  may include recessed portions  42   c  extended from the front surface portion  30   b  in which the inlet  31  is formed to the rear surface portion  30   a  coupled to the driving shaft  13  and first dehydrating holes  43   c  formed in the recessed portions  42   c . The recessed portions  42   c  may have a length direction parallel with the driving shaft  13  driving the washing tub  30 . In addition, the recessed portions  42   c  may be formed in the plural in parallel with each other in the circumferential direction of the washing tub  30 . The recessed portions  42   c  may be spaced apart from each other and be arranged in the plural, in the direction of the driving shaft  13 . 
     Referring to  FIGS. 9 and 10 , the recessed portions  42   c  may be spaced apart from each other and be arranged as a plurality of rows, in the direction of the driving shaft  13 . As an example, the recessed portions  42   c  may be arranged in eight rows in the direction of the driving shaft  13 . As described above, the respective recessed portions  42   c  are provided with the first dehydrating holes  43 . In addition, the first dehydrating holes  43   c  may be each positioned at both end portions of the recessed portion  42   c , and separate first dehydrating holes  43   c  may be further provided at the same interval between the first dehydrating holes  43   c  each positioned at both end portions of the recessed portion  42   c . In addition, second dehydrating holes  46   c  may be formed between the respective recessed portions  42   c.    
     The recessed portion  42   c  may include a first inclined surface  421   c  inclined downwardly in the circumferential direction of the washing tub  30 , a second inclined surface  422   c  connected to the first inclined surface  421   c  and inclined upwardly in the circumferential direction of the washing tub  30 , and a first connecting surface  44   c  flatly connecting the first inclined surface  421   c  and the second inclined surface  422   c  to each other. In addition, the recessed portion  42   c  may further include second connecting surfaces  47   c  each connecting between the first connecting surface  421   c  and the respective inclined surfaces  421   c  and  422   c . A protruding portion  41   c  connecting the first inclined surface  421   c  and the second inclined surface  422   c  to each other may have a round shape. 
     The first dehydrating holes  43   c  may be provided in the plural at both end portions of the first connecting surface  44   c . Although not illustrated, the first dehydrating holes  43   c  may be additionally provided between the first dehydrating holes  43   c  each positioned at both end portions of the first connecting surface  44   c.    
     Guide grooves  430   c  may be formed in the first connecting surface  44   c . The guide groove  430   c  may be positioned to have an outer diameter greater than that of the first dehydrating hole  43   c  formed in the first connecting surface  44   c  and be concentric with the first dehydrating hole  43   c . The guide groove  430   c  may have a shape of which a cross sectional area is decreased toward the first dehydrating hole  43   c . As an example, a distance between an outer circumferential surface of the guide groove  430   c  and an outer circumferential surface of the first dehydrating hole  43   c  may be 1 mm or more. The distance between the outer circumferential surface of the guide groove  430   c  and the outer circumferential surface of the first dehydrating hole  43   c  may be set to 1 mm or more to improve a moisture content of the laundry by 1% or more. 
     That is, the washing machine  1  that may increase the washing force of the laundry and maximize dehydration efficiency of the laundry using the patterns  40 ,  40   a ,  40   c , and  40   c  according the diverse exemplary embodiment of the present disclosure may be provided. In addition, the patterns  40 ,  40   a ,  40   c , and  40   c  having an improved structure may be provided to maximize rigidity of the washing tub  30 , such that a user may use the washing tub  30  and the washing machine  1  for a long period of time. 
       FIG. 11  is a cross-sectional view illustrating a washing machine  2  according to another exemplary embodiment of the present disclosure. 
     Since most of the structures of the washing machine  2  illustrated in  FIG. 11  are similar to those of the washing machine  1  illustrated in  FIG. 1 , a description for contents overlapping those of the washing machine  1  illustrated in  FIG. 1  will be omitted. 
     However, the washing machine  2  according to another exemplary embodiment of the present disclosure is different from the washing machine  1  illustrated in  FIG. 1  in that a water tub  20  and a washing tub  70  disposed in a body  10  are disposed in a direction approximately horizontal to an installation surface of the washing machine  2 . 
     However, as described above, disposition structures of the water tub  20  and the washing tub  70  are not limited thereto. That is, the water tub  20  and the washing tub  70  may be disposed to be inclined with respect to the installation surface of the washing machine  2  as in the washing machine  1  according to an exemplary embodiment of the present disclosure. 
     The washing machine  2  includes the body  10  having a front surface in which an inlet  11  for injecting the laundry is formed, the water tub  20  installed in the body  10  and storing washing water therein, and the washing tub  70  rotatably provided in the water tub  20  and accommodating the laundry therein. 
     The washing tub  70  is rotatably supported by a driving shaft  13  coupled to a rear surface portion  70   a  thereof and penetrating through the rear surface portion  20   b  of the water tub  20 . 
     The driving shaft  13  is coupled to a driving motor  14 . Therefore, the washing tub  70  may receive driving force of the driving motor  14  from the driving shaft  13  to rotate. The driving motor  14  rotates the washing tub  70  at a low speed in one direction or the other direction at the time of performing washing, and rotates the washing tub  70  at a high speed in one direction at the time of performing dehydration. 
     As described above, since the water tub  20  and the washing tub  70  are disposed in the direction horizontal to the installation surface of the washing machine  2 , and the driving shaft  13  is also disposed in the direction horizontal to the installation surface of the washing machine  2 . Therefore, a central axis line  13   a  of the driving shaft  13  may be parallel with the installation surface of the washing machine  2 . 
       FIG. 12  is a perspective view of a washing tub  70  illustrated in  FIG. 11  when viewed from the front, and  FIG. 13  is an exploded view of the washing tub  70  illustrated in  FIG. 12 . 
     Hereinafter, the washing tub  70  according to yet still another exemplary embodiment of the present disclosure will be described with reference to  FIGS. 11 through 13 . 
     For convenience of explanation, a portion adjacent to a door  12  illustrated in  FIG. 11  is defined as the front, and a portion adjacent to the driving motor  14  illustrated in  FIG. 11  is defined as the rear. In addition, in illustrating the washing tub  70  in  FIGS. 12 and 13 , only a circumferential portion  70   c  having a plurality of protruding portions  100  formed on an inner surface thereof is illustrated, and a rear surface portion  70   a  and a front surface portion  70   b  that are omitted may be replaced, respectively, by the rear surface portion  30   a  and the front surface portion  30   b  illustrated in  FIG. 2 . 
     The washing tub  70  may have a cylindrical shape opened toward the front to be connected to the inlet  11  formed in the front surface of the washing machine  1 . Since most of the configurations of the washing tub  70  are similar to those of the washing tub  30  illustrated in  FIG. 2 , a description for overlapping contents will be omitted. 
     The washing tub  70  includes the rear surface portion  70   a  coupled to the driving shaft  13 , the front surface portion  70   b  in which an inlet  71  through which the laundry is injected is formed, and the circumferential portion  70   c  connecting the rear surface portion  70   a  and the front surface portion  70   b  to each other. In addition, a plurality of lifters  73  lifting and dropping the laundry depending on rotation of the washing tub  70  are installed on the inner surface of the circumferential portion  70   c.    
     The inner surface of the circumferential portion  70   c  of the washing tub  70  configures an inner circumferential surface of the washing tub  70 . 
     The inlet  71  of the washing tub  70  is connected to the inlet  11  formed in the front surface of the body  10 . Therefore, the washing tub  70  may accommodate the laundry injected through the inlet  11  and the inlet  71  therein. 
     Referring to  FIGS. 12 and 13 , the washing tub  70  includes the plurality of protruding portions  100  protruding from the inner circumferential surface of the washing tub  70  toward an inner portion of the washing tub  70 . In detail, the plurality of protruding portions  100  may be formed on the inner surface of the circumferential portion  70   c  to form a pattern. In describing a structure of the protruding portion  100 , the inner circumferential surface of the washing tub  70  and the inner surface of the circumferential portion  70   c  indicate the same component, and may be used together. 
     The plurality of protruding portions  100  may be disposed in parallel with each other in the circumferential direction of the washing tub  70  to be easily in contact with the laundry injected into the washing tub  70 . 
     The washing tub  70  includes a plurality of fastening portions  71  formed on the inner surface of the circumferential portion  70   c  and having the plurality of lifters  73  coupled thereto. 
     As illustrated in  FIG. 13 , the plurality of fastening portions  71  may be disposed, respectively, between the plurality of protruding portions  100  disposed in parallel with each other. 
     Therefore, the plurality of protruding portions  100  disposed in parallel with each other between the plurality of fastening portions  71  may configure the respective patterns, and the fastening portions  71  may be disposed between the respective patterns. 
     In addition, the plurality of fastening portions  71  include a plurality of fastening holes, respectively, and the plurality of lifters  73  may be coupled to the inner circumferential surface of the washing tub  70  through the fastening holes of the fastening portions  71  corresponding thereto, respectively. 
     Hereinafter, a structure of the plurality of protruding portions  100  will be described. 
     The respective protruding portions  100  protrude from the inner circumferential surface of the washing tub  70  toward the inner portion of the washing tub  70 , and are extended from a portion of the inner circumferential surface of the washing tub  70  adjacent to the inlet  11  in a direction that becomes distant from the inlet  11 . 
     In addition, the respective protruding portions  100  may be replaced by recessed portions concave from the inner circumferential surface of the washing tub  70  toward the outside. However, a case in which the respective protruding portions  100  protrude toward the inner portion of the washing tub  70  will hereinafter be described by way of example. 
     The plurality of protruding portions  100  protruding toward the inner portion of the washing tub  70  may have a shape in which they protrude inwardly from both ends of the respective protruding portions  100  in a width direction to be inclined upwardly, and surfaces of the respective protruding portions  100  may be curved surfaces. 
     The respective protruding portions  100  may be extended in the length direction of the washing tub  70 . In addition, the respective protruding portions  100  may be extended from a front end  70 F of the circumferential portion  70   c  adjacent to the inlet  11  to a rear end  70 R of the circumferential portion  70   c  opposed to the front end  70 F. 
     In addition, at least part of the respective protruding portions  100  are curved in a helix direction. The meaning that at least part of the respective protruding portions  100  are curved in the helix direction is that at least part of the respective protruding portions  100  are extended in a helix shape in the length direction of the washing tub  70  on the inner circumferential surface of the washing tub  70 . 
     Therefore, the plurality of protruding portions  100  may interfere in the laundry in the washing tub  70 , and move the laundry on the inner circumferential surface of the washing tub  70 . 
     In detail, at least parts of the protruding portion  100  may be curved in the helix direction to move the laundry in the washing tub  70  in a desired direction in a process in which the washing machine  2  is operated in a dehydrating mode. As an example, the washing tub  70  according to exemplary embodiment of the present disclosure may be configured to rotate at a high speed in a counterclockwise direction at the time of performing the dehydration, and at least part of the respective protruding portions  100  may be configured to be curved in a right handed screw direction. 
     At least part of the respective protruding portions  100  are curved in the right handed screw direction, such that the laundry accommodated in the washing tub  70  may interfere in the plurality of protruding portions  100  and move from a portion adjacent to the inlet  11  in the direction that becomes distant from the inlet  11  along the plurality of protruding portions  100 , during a period in which the washing tub  70  performs the dehydration of the laundry while rotating at the high speed in the counterclockwise direction. That is, the plurality of protruding portions  100  may guide the laundry accommodated in the washing tub  70  so that the laundry moves from the front end  70 F of the washing tub  70  to the rear end  70 R of the washing tub  70 , at the time of performing the dehydration. 
     In addition, in the case in which the washing tub  70  is configured to rotate at a high speed in a clockwise direction at the time of performing the dehydration, at least part of the respective protruding portions  100  may be configured to be curved in a left handed screw direction to move the laundry in the washing tub  70  toward the rear end  70 R of the washing tub  70  at the time of performing the dehydration. 
     In addition, it may be understood that at least part of the respective protruding portions  100  are curved in a direction opposed to a rotation direction of the washing tub  70 . 
     The meaning that the plurality of protruding portions  100  are curved may be that portions or entirety of the plurality of protrusion portions  100  are curved while forming curved lines along the inner circumferential surface of the washing tub  70  formed as a curved surface. 
     In  FIGS. 12 and 13 , a rotation direction of the washing tub  70  rotating in the counterclockwise direction is denoted by an arrow “R”, and a direction in which at least parts of the protruding portions  100  are curved in the right handed screw direction is denoted by an arrow “C 1 ”. 
     As described above, the rotation direction R of the washing tub  70  at the time of performing the dehydration may be set to the counterclockwise direction. In addition, the rotation direction R of the washing tub  70  rotating in the counterclockwise direction may be represented as a direction from the left toward the right in the exploded view of the washing tub  70  illustrated in  FIG. 13 . 
     As illustrated in  FIG. 12 , at least part of the protruding portions  100  may have a helix shape curved in the right handed screw direction. 
     In addition, in the case in which the washing tub  70  is viewed from the top of the front of the washing tub  70 , it may be understood that the direction C 1  in which the respective protruding portions  100  positioned at a lower portion of an inner side of the washing tub  70  are curved is the direction from the right toward the left. However, since the washing tub  70  rotates, in the case in which the washing tub  70  is viewed from the bottom of the front of the washing tub  70 , a direction in which the respective protruding portions  100  positioned at an upper portion of the inner side of the washing tub  70  are curved is viewed as a direction from the left toward the right. 
     Referring to  FIG. 13 , in the washing tub  70  rotating in the counterclockwise direction, a rotation direction R of the circumferential portion  70   c  may be represented by the direction from the left toward the right in the exploded view of the washing tub  70 . 
     In addition, the direction C 1  in which the respective protruding portions  100  are curved may be represented to be inclined in the direction from the right toward the left. Therefore, it may be described that the direction in which at least part of the respective protruding portions  100  are curved is the direction opposed to the rotation direction of the washing tub  70 . 
     In manufacturing the washing tub  70  according to yet still another exemplary embodiment of the present disclosure, the circumferential portion  70   c  may be manufactured by forming the plurality of protruding portions  100  curved in the direction C 1  from the right toward the left on a metal plate having a rectangular shape and curving the metal plate on which the plurality of protruding portions  100  are formed in a cylindrical shape. 
     Therefore, at least part of the respective protruding portions  100  formed on the inner circumferential surface of the washing tub  70  having the cylindrical shape may be configured to be curved in the right handed screw direction to correspond to the washing tub  70  rotating in the counterclockwise direction, and the plurality of protruding portions  100  may move the laundry gathered toward the inlet  11  at the time of performing the dehydration toward the rear end  70 R of the washing tub  70 . However, it is preferable that the respective protruding portions  100  are curved in a level enough to move the laundry from the front end  70 F of the washing tub  70  toward the rear end  70 R of the washing tub  70  and preventing the laundry from being gathered toward the rear surface portion  70   a  of the washing tub  70 . For example, in  FIG. 13 , the direction C 1  in which at least part of the respective protruding portions  100  are curved may form an obtuse angle with respect to the rotation direction R of the washing tub  70 , and the obtuse angle may exceed 90 degrees and be 135 degrees or less. 
     In addition, in describing a relationship between the rotation direction of the washing tub  70  at the time of performing the dehydration and the direction in which the protruding portions  100  are curved, the washing tub  70  may be divided into an upper portion and a lower portion on the basis of the central axis line  13   a  illustrated in  FIG. 12 . 
     In describing the washing tub  70  rotating the counterclockwise direction and the plurality of protruding portions  100  curved in the direction opposed to the rotation direction R of the washing tub  70 , the respective protruding portions  100  positioned at the lower portion of the washing tub  70  move in the direction from the left toward the right, and at least part of the respective protruding portions  100  positioned at the lower portion of the washing tub  70  are curved in the direction from the right toward the left. 
     In addition, the protruding portions  100  positioned at the upper portion of the washing tub  70  move in the direction from the right toward the left, and at least part of the respective protruding portions  100  disposed at the upper portion of the washing tub  70  are curved in the direction from the left toward the right. However, since the washing tub  70  rotates around the central axis line  13   a , the upper portion and the lower portion of the washing tub  70  described above are relative portions of the washing tub  70  that rotates. 
     Therefore, the meaning that at least part of the respective protruding portions  100  are curved in the direction opposed to the rotation direction R of the washing tub  70  may be that at least part of the respective protruding portions  100  are curved in a direction opposed to an instantaneous moving direction of the respective protruding portions  100  depending on rotation of the washing tub  70 , and may also be that at least part of the respective protruding portions  100  are curved in the direction opposed to the rotation direction R of the washing tub  70  in an exploded view of the circumferential portion  70   c.    
     As described above, the plurality of protruding portions  100  protruding on the inner circumferential surface of the washing tub  70  may be curved in the direction opposed to the rotation direction R of the washing tub  70  to move the laundry in the washing tub  70  that rotates in the direction that becomes distant from the inlet  11 . 
     In addition, the plurality of protruding portions  100  may be continuously disposed in the circumferential direction of the washing tub  70  to effectively move the laundry that is in contact with the inner surface of the circumferential portion  70   c  and rotates from the front to the rear. 
     Therefore, the washing tub  70  including the plurality of protruding portions  100  may prevent the laundry from being moved and gathered toward the inlet  11  in washing and dehydrating processes, and prevent the laundry from being sandwiched and damaged in a gap between the inlet  11  and the door  12  or a diaphragm (not illustrated). 
     A structure moving the laundry from the front end  70 F of the washing tub  70  to the rear end  70 R of the washing tub  70  through the plurality of protruding portions  100  to prevent the laundry from being gathered and damaged toward the inlet  11  at the time of performing the dehydration is described by way of example in the abovementioned exemplary embodiments, but the present disclosure is not limited thereto. That is, the laundry in the washing tub  70  may move in a desired direction in a dehydrating process by changing the direction and a level in which at least part of the respective protruding portions  100  are curved. 
       FIG. 14  is an enlarged view of a protruding portion  100  illustrated in  FIG. 13 . 
     Referring to  FIG. 14 , each protruding portion  100  includes a front end portion  100   a  adjacent to the inlet  11 , a central portion  100   b  connected to the front end portion  100   a , and a rear end portion  100   c  connected to the central portion  100   b.    
     As illustrated in  FIG. 14 , the front end portion  100   a  of the protruding portion  100  adjacent to the inlet  11  may be a portion of the protruding portion  100  adjacent to the front end  70 F of the washing tub  70 , and the rear end portion  100   c  of the protruding portion  100  may be a portion of the protruding portion  100  adjacent to the rear end  70 R of the washing tub  70 . 
     In addition, the central portion  100   b  is curved in the helix direction. As an example, in the case in which the washing tub  70  is configured to rotate in the counterclockwise direction at the time of performing the dehydration, the central portion  100   b  may be configured to be curved in the right handed screw direction. That is, the central portion  100   b  is curved in the direction C 1  opposed to the rotation direction R of the washing tub  70 , and the front end portion  100   a  and the rear end portion  100   c  may be formed in parallel with a shaft (the driving shaft  13 ) of the washing tub  70 . 
     As described above, the washing tub  70  may be configured to rotate in the counterclockwise direction at the time of performing the dehydration and the central portion  100   b  of the protruding portion  100  may be curved in the right handed screw direction to move the laundry interfering in the central portion  100   b  at the time of performing the dehydration toward the rear end portion  100   c.    
     That is, the central portion  100   b  of each protruding portion  100  may be curved in the direction C 1  opposed to the rotation direction R of the washing tub  70  to move the laundry in contact with the central portion  100   b  toward the rear end portion  100   c.    
     In addition, the rear end portion  100   c  is formed in parallel with the driving shaft  13 , such that the laundry moved to the rear end portion  100   c  may be moved forward and rearward on the rear end portion  100   c . Therefore, the rear end portion  100   c  may disperse the laundry on the rear end portion  100   c  and prevent the laundry from being lumped or twisted on the rear surface portion  70   a  of the washing tub  70 . 
     In addition, the front end portion  100   a  is also formed in parallel with the driving shaft  13 , such that the laundry on the front end portion  100   a  may be dispersed. Therefore, the laundry on the front end portion  100   a  may more effectively enter the central portion  100   b.    
     It is preferable that the central portion  100   b  of each protruding portion  100  is configured to be longer than the front end portion  100   a  and the rear end portion  100   c  to effectively guide movement of the laundry. 
     In addition, the entirety of each protruding portion  100  may be configured to be curved in the right handed screw direction without being divided into the front end portion  100   a , the central portion  100   b , and the rear end portion  100   c , and the entirety of the protruding portion  100  may be configured to be curved in the direction C 1  opposed to the rotation direction R of the washing tub  70 . In addition, the protruding portion  100  may include only a front end portion  100   a  and a central portion  100   b  or only a central portion  100   b  and a rear end portion  100   c.    
     However, a detailed structure of each protruding portion  100  is not limited to the example described above, but may be replaced by various structures in which the protruding portion  100  is curved so that the laundry moves from a portion adjacent to the inlet  11  in the direction that becomes distant from the inlet  11  along the protruding portion  100 . 
       FIG. 15  is a partially enlarged perspective view of the washing tub  70  illustrated in  FIG. 12 , and  FIG. 16  is a cross-sectional view taken along line E-E of the washing tub  70  illustrated in  FIG. 15 . 
     Referring to  FIGS. 14 to 16 , each protruding portion  100  includes a plurality of recessed portions  110  formed in the length direction of the protruding portion  100 . 
     Each protruding portion  100  protrudes from the inner circumferential surface of the washing tub  70  toward the inner portion of the washing tub  70 , and the plurality of recessed portions  110  formed in the protruding portion  100  are formed to be concave from the inner circumferential surface of the washing tub  70  toward the outside of the washing tub  70 . 
     Therefore, in each protruding portion  100 , the protruding portions protruding from the inner circumferential surface of the washing tub  70  and the recessed portions  110  concave from the inner circumferential surface of the washing tub  70  are sequentially disposed in the direction that becomes distant from the inlet  11 . Therefore, the laundry may more effectively move from the inlet  11  in the direction that becomes distant from the inlet  11 . 
     In addition, the respective recessed portions  110  may have an oval shape extended in the length direction of the protruding portion  100 . Therefore, the laundry may more effectively move from the front of the washing tub  70  to the rear of the washing tub  70  along the plurality of protruding portion  100 . 
     In addition, the washing tub  70  includes a plurality of dehydrating holes  121 ,  122 , and  123  formed in the plurality of protruding portions  100 . 
     In detail, the respective protruding portions  100  include at least one first dehydrating hole  121  formed in the recessed portions  110 . 
     Water separated from the laundry in the dehydrating process may easily move to the recessed portions  110 , and the water moving to the recessed portions  110  may be easily drained to the outside of the washing tub  70  through the first dehydrating holes  121 . 
     Although a case in which two first dehydrating holes  121  are formed in each recessed portion  110  is illustrated by way of example in  FIGS. 14 to 16 , a size and the number of first dehydrating holes  121  formed in the recessed portion  110  may be variously modified. 
     In addition, the protruding portions  100  described above may be replaced by a plurality of recessed portions forming the pattern of the washing tub and formed to be concave from the inner circumferential surface of the washing tub. In this case, a plurality of protruding portions may be formed in each recessed portion extended in the length direction of the washing tub. In addition, the first dehydrating holes may be formed between an inner side of the recessed portion and an outer side of the protruding portion to easily drain the water moving to the inner side of the concave recessed portion. 
     In addition, the respective protruding portions  100  include at least one second dehydrating hole  122  formed between the plurality of recessed portions  110 . 
     As illustrated in  FIGS. 14 and 15 , three second dehydrating holes  122  may be disposed in the width direction of the protruding portion  100 , respectively, between the plurality of recessed portions  110 . 
     The second dehydrating holes  122  may be formed between each recessed portion  110  formed in the protruding portion  100  and a recessed portion  110  adjacent to the recessed portion  110  to more effectively drain the water in the washing tub  70  to the outside. 
     In addition, the washing tub  70  includes at least one third dehydrating hole  123  formed between the plurality of protruding portions  100 . 
     Since the plurality of protruding portions  100  formed on the inner circumferential surface of the washing tub  70  protrude toward the inner portion of the washing tub  70 , spaces between the plurality of protruding portions  100  have a height lower than that of the protruding portions  100 . Therefore, the water separated from the laundry in the dehydrating process may easily move between the plurality of protruding portions  100 . 
     Therefore, the third dehydrating holes  123  formed between the plurality of protruding portions  100  may easily drain the water moving between the plurality of protruding portions  100  to the outside of the washing tub  70 . 
     In addition, since the plurality of protruding portions  100  are continuously disposed in the circumferential direction of the washing tub  70 , the third dehydrating holes  123  may be formed on a boundary between each protruding portion  100  and a protruding portion  100  adjacent to each protruding portion  100 . In addition, a plurality of third dehydrating holes  123  may be disposed in the length direction of the protruding portions  100  on the boundaries between the plurality of protruding portions  100 . 
       FIG. 17  is a perspective view of a washing tub  80  according to yet still another exemplary embodiment of the present disclosure when viewed from the front, and  FIG. 18  is an exploded view of the washing tub  80  illustrated in  FIG. 17 . 
     Hereinafter, a structure of the washing tub  80  according to yet still another exemplary embodiment of the present disclosure will be described with reference to  FIGS. 17 and 18 . 
     However, since most of the structures of the washing tub  80  illustrated in  FIGS. 17 and 18  are the same as those of the washing tub  70  illustrated in  FIGS. 12 and 13 , a description for overlapping contents will be omitted. 
     The washing tub  80  includes a plurality of protruding portions  200  protruding on an inner surface thereof. The plurality of protruding portions  200  are formed on an inner surface of a circumferential portion  80   c  (an inner circumferential surface of the washing tub  80 ), and the respective protruding portions  200  are extended from a portion adjacent to the inlet  11  in the direction that becomes distant from the inlet  11 . 
     In addition, it may be understood that at least part of the respective protruding portions  200  are curved in a helix direction and are curved in a direction C 2  opposed to a rotation direction R of the washing tub  80 . 
     In detail, as illustrated in  FIG. 17 , the rotation direction R of the washing tub  80  at the time of performing dehydration may be set to the counterclockwise direction, and at least parts of the protruding portions  200  are configured to be curved in the right handed screw direction. 
     In addition, the rotation direction R of the washing tub  80  rotating in the counterclockwise direction may be represented as a direction from the left toward the right in the exploded view of the washing tub  80  illustrated in  FIG. 18 . In addition, the respective protruding portions  200  may have a linear shape inclined in the direction opposed to the rotation direction R of the washing tub  80  in the exploded view of the circumferential portion  80   c.    
     In manufacturing the washing tub  80  according to yet still another exemplary embodiment of the present disclosure, the circumferential portion  80   c  may be manufactured by forming the plurality of protruding portions  200  having the linear shape inclined in the direction C 2  from the right toward the left on a metal plate having a rectangular shape and curving the metal plate on which the plurality of protruding portions  200  are formed in a cylindrical shape. Therefore, at least part of the respective protruding portion  200  formed on the inner surface of the washing tub  80  may be configured to be curved in the right handed screw direction to correspond to the washing tub  80  rotating in the counterclockwise direction, and the respective protruding portions  200  may be curved in the direction C 2  opposed to the rotation direction R of the washing tub  70  rotating in the counterclockwise direction. 
     In addition, each of the plurality of protruding portions  200  formed on the inner surface of the washing tub  80  may have a helix shape extended from a front end  80 F of the washing tub  80  toward a rear end  80 R of the washing tub  80  in the direction opposed to the rotation direction of the washing tub  80 . 
     Therefore, the plurality of protruding portions  200  formed on the inner surface of the washing tub  80  may move the laundry in the washing tub  80  from a portion adjacent to the inlet  11  in the direction that becomes distant from the inlet  11 , and prevent the laundry from being sandwiched and damaged between the inlet  11  and the door  12 . 
     In addition, each protruding portion  200  includes a plurality of recessed portions formed in the length direction of the protruding portion  200 , and a water tub includes a plurality of dehydrating holes formed in an inner surface thereof. 
     Since structures of the plurality of recessed portions formed in each protruding portion  200  and the plurality of dehydrating holes are similar to those of the recessed portions  110  and the first to third dehydrating holes  121 ,  122 , and  123  illustrated in  FIG. 15 , a description for overlapping contents will be omitted. 
     As described above, in the washing machine  2  according to another exemplary embodiment of the present disclosure, at least parts of the plurality of protruding portions  100  or  200  protruding on the inner surface of the washing tub  70  or  80  may be curved in the right handed screw direction (at least parts of the protruding portions  100  or  200  may be curved in the direction C 2  opposed to the rotation direction R of the washing tub  70  or  80 ) to correspond to the washing tub  70  or  80  configured to rotate in the counterclockwise direction at the time of performing the dehydration to move the laundry adjacent to the inlet  11  in the direction that becomes distant from the inlet  11 . Therefore, a phenomenon that the laundry in the washing tub  70  or  80  that rotates is gathered toward the inlet  11  to be sandwiched between the inlet  11  and the door  12  may be prevented. 
     In addition, the washing tub  70  or  80  may include the first and second dehydrating holes  121  and  122  each formed in the plurality of protruding portions  100  or  200  and the third dehydrating holes  123  formed between the plurality of protruding portions  100  to effectively improve a moisture content. 
     Although the diverse exemplary embodiments of the present disclosure have been individually described hereinabove, the respective exemplary embodiments are not necessarily implemented singly, but may also be implemented so that configurations and operations thereof are combined with those of one or more other exemplary embodiments. 
     In addition, specific exemplary embodiments have been illustrated and described hereinabove. However, the present disclosure is not limited to only the abovementioned exemplary embodiments, but may be variously modified by those skilled in the art to which the present disclosure pertains without departing from the scope and spirit of the present disclosure stated in the claims.