Patent Publication Number: US-7900485-B2

Title: Washing machine

Description:
This Nonprovisional application claims priority under 35 U.S.C. §119(a) on Patent Application No. 10-2006-0070796 filed in Korea on Jul. 27, 2006, the entire contents of which are hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a washing machine and, more particularly, to a washing machine having legs at a base to adjust the height thereof. 
     2. Description of the Background Art 
     In general, a washing machine removes pollutes from clothes and linens by sequentially performing predetermined operations, such as washing, rinsing, and spin-drying, using water and detergent. Hereinafter, laundry is referred as clothes and linens. 
     The washing machine includes a base at the bottom of the washing machine. The base supports the weight of the washing machine and includes a plurality of legs for adjusting the installation height of the washing machine and for balancing the washing machine, horizontally. Each of the legs includes a bolt unit screw-assembled at one of four corners of the base and a support disposed at the bottom of the bolt unit and placed at a location where the washing machine is installed. If the leg rotates in one direction, the height of the washing machine increases because the bolt unit is drawn out from the base in a downward direction. On the contrary, if the leg rotates in the other direction, the height of the washing machine decreases because the bolt unit is inserted into the base in an upward direction. That is, the installation height of the washing machine can be adjusted, and the washing machine can be horizontally balanced by turning the blot unit in one of directions. 
     However, a washing machine has a problem that the legs may be over-unscrewed or completely separated from the base when the legs are adjusted in height. That is, the bolt unit, screw-assembled at the base, has a limited length. Therefore, the unscrew height of the leg is limited. However, a user generally adjusts the height of the legs without the unscrew height considered. 
     If a user completely unscrews the legs from the base because the user adjusts the heights of the legs without the unscrew height considered, the user must reassemble the legs at the base. it is annoying to a user or it takes a long time to install the washing machine. If the legs are over-unscrewed from the base when a user adjusts the legs in height, the legs are unstably disposed at the base. That is, the washing machine is unstably installed. Therefore, the washing machine is vibrated and generates noise when the washing machine operates. 
     SUMMARY OF THE INVENTION 
     Accordingly, an aspect of the present invention is to solve at least the problems and disadvantages of the background art. In accordance with an aspect of the present invention, a washing machine includes a base, a plurality of legs, and an over-unscrewed prevention member. The base is formed at a bottom of the washing machine. A plurality of the legs are disposed at the base and each having a bolt unit that is height-adjustably assembled at the base. The over-unscrewed prevention member is disposed at the bolt unit of each leg and caught by the base when the legs are unscrewed so as to set a maximum unscrewed height of the legs. 
     The base may include through-holes to receive the bolt units. The over-unscrewed prevention member may be disposed at a top of each bolt unit that penetrates the through-hole to be caught at the top of the through-hole when the legs are maximally unscrewed. Also, the through-hole may have an inner circumference surface with a female screw formed to be screwed with a male screw formed at an external circumference surface of the bolt unit. The base may further include a base bracket having assembling holes formed corresponding to bottom surfaces of the through-holes to receive the bolt units with the assembling holes penetrated. The base bracket may be made of a material having hardness greater than the through-hole. 
     However, the base may include through-holes assembled with the bolt units and a base bracket having assembling holes formed corresponding to bottom surfaces of the through-holes to receive the bolt units with the assembling holes penetrated. The over-screw prevention member may be disposed at an upper part of the bolt unit that penetrates the assembling hole to be caught at a top surface of the base bracket when the legs are maximally unscrewed. Also, the through-hole may have an inner circumference surface with a female screw formed to be screwed with a male screw formed at the outer circumference surface of the bolt unit. The base bracket may be made of a material having hardness greater than the through-hole. The through-hole may include a receiving groove to movably receive the over-unscrewed prevention member to prevent the over-unscrewed prevention member from disturbing when the legs are adjusted in height. 
     The over-unscrewed prevention member may include a fixing nut or a snap ring, which is assembled and fixed at an upper part of the bolt unit. The over-unscrewed prevention member may be the fixing nut, and the fixing nut is fixed using adhesive after the bolt unit is assembled. The over-unscrewed prevention member may be the snap ring, and the snap ring is detachably assembled at a mounting groove formed along an upper part of the bolt unit. The snap ring may be one of an O-ring, a C-ring, and an E-ring. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described in detail with reference to the following drawings in which like numerals refer to like elements. 
         FIG. 1  is a cross-sectional view of a washing machine according to an embodiment of the present invention; 
         FIG. 2  is a side cross-sectional view of an assembling structure of a base and a leg shown in  FIG. 1 ; 
         FIG. 3  is an exploded view of the assembling structure of  FIG. 2 ; 
         FIG. 4  is a side cross-sectional view of an assembling structure of a base and a leg of a washing machine according to another embodiment of the present invention; 
         FIG. 5  is a cross-sectional view of  FIG. 4  taken along the line A-A; 
         FIG. 6  is a side cross-sectional view of an assembling structure of a base and a leg of a washing machine according to another embodiment of the present invention; and 
         FIG. 7  is a side exploded view of the assembling structure of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will be described in a more detailed manner with reference to the drawings. 
     It is an object of the present invention to provide a washing machine for preventing legs from being over-unscrewed or from being completely separated when the legs are adjusted in height. 
     It is another object of the present invention to provide a washing machine for preventing workability from being lowered and preventing the washing machine from being unstably installed by preventing the legs from being completely separated and from being over-unscrewed. 
     Hereinafter, a washing machine according to an embodiment of the present invention will be described with reference to accompanying drawings. 
       FIG. 1  is a cross-sectional view of a washing machine according to an embodiment of the present invention,  FIG. 2  is a side cross-sectional view of an assembling structure of a base and a leg shown in  FIG. 1 , and  FIG. 3  is an exploded view of the assembling structure of  FIG. 2 . 
     Referring to  FIG. 1 , the washing machine  1  according to the present embodiment includes a cabinet  2  forming an exterior, a tub  8  horizontally disposed in the cabinet  2 , which is elastically supported by a spring  4  and a damper  6 , a drum  10  rotatably disposed in the tub  8  and having a plurality of water holes  10 A for letting water passing through, lifters  12  for lifting up the water at a predetermined height and letting the washing waster falling, and a motor  14  disposed at the rear end of the tub  8  for transferring a rotating force to the drum  10 . 
     A cabinet cover  16  is disposed at a front side of the cabinet  2  to form a front side of the washing machine  1 , a top plate  18  is disposed at the top of the cabinet  2  for forming the top of the washing machine  1 , and a base  20  is disposed at the bottom of the cabinet  2  to form the bottom of the washing machine  1 . A laundry entrance  16 A is formed at the front side of the cabinet cover  16 , and a door  22  is rotatably disposed to open or to close the laundry entrance. A control panel  24  is disposed at the upper side of the cabinet cover  16  to display the operating states of the washing machine  1  and to control the operations of the washing machine  1 . 
     A water supply device  26  is disposed between the top plate  18  and the tub  8  to supply water to the tub  8 . The water supply device  26  includes a water supply hose  26 A having one end connected to the inner side of the cabinet  2  and the other end connected to an external water source, a water supply valve  26 B disposed on the water supply hose  26 A, and a water supply bellows  26 C disposed between the water supply hose  26 A and the tub  10  to be communicated to each other. A detergent supply device  27  is disposed between the water supply hose  26 A and the water supply bellows  26 C to supply the detergent to the inside of the tub  8 . 
     A drain device  28  is disposed between the base  20  and the tub  8  to drain the water from the tub  8  to the outside. The drain device  28  includes a drain hose  28 A having one end connected to the inner side of the cabinet  2  and the other connected to the outside, a drain pump  26 B connected to the drain hose  28 A disposed at the inner side of the cabinet  2 , and a drain bellows  28 C for connecting the drain pump  28 B and the tub  10 . 
     Referring to  FIG. 2  and  FIG. 3 , the washing machine  1  includes a plurality of legs  30  each having a bolt unit  32  assembled to the base  20  to adjust a height thereof, and an over-unscrewed prevention member  40  disposed at the bolt unit  32  for preventing the legs  30  from being over-unscrewed from the base when the heights of the legs are adjusted. The base  20  includes a plurality of through-holes  20 A formed at four corners of the base  20  to receive the legs  30 . A female screw is formed at an inside circumference surface of the through-hole  20 A to be screwed with the bolt unit  32 . 
     The legs  30  are members to adjust the installation height of the washing machine  1  and to horizontally balance the washing machine  1  as well as supporting the weight of the washing machine  1 . Each of the legs  30  includes a bolt unit  32  that is height-adjustably assembled at the through-hole  20 A of the base and a support  34  disposed at the bolt unit  32  to absorb the vibration of the washing machine  1 . The bolt unit  32  is formed lengthily longer than the through-hole  20 A in an up and down direction, and a male screw is formed at the outer circumference surface of the bolt unit  32  to be screw-assembled with the female screw. 
     The bolt unit  32  includes a lock unit  36  for preventing the bolt unit  32  from being rotated after the height of the leg is adjusted by being closely attached at the bottom surface of the base  20 . Therefore, the lock unit  36  prevents the leg  30  from being unscrewed by the vibration of the washing machine  1 . 
     The support  34  is a member placed at a location of installing the washing machine  1  for supporting the weight of the washing machine  1 . The support  34  is made of an absorbing material for absorbing vibration generated when the washing machine  1  operates. 
     The over-unscrewed prevention member  40  includes a fixing nut  40  fixed at the bolt unit  32  that penetrates the through-hole  20 A to be caught at the top of the through-hole  20 A. The fixing nut  40  is fixed at the bolt unit  32  using an adhesive  38  after the bolt unit  32  is screwed at a proper position. The fixing position of the fixing unit  40  is a position where the fixing unit  40  is caught at the top of the through-hole  20 A when the leg  30  is maximally unscrewed to stably support the washing machine  1  at the highest height. Therefore, when the legs  30  are unscrewed at the highest height, the fixing nut  40  is caught at the top of the through-hole  20 A, thereby restricting the leg  30  from being over-unscrewed. Also, the adhesive  38  is a bond coated on a female screw of the fixing nut  40  or coated on a male screw of the bolt unit  32  for preventing the fixing nut  40  from being rotated. 
     Hereinafter, a process of assembling a washing machine according to an embodiment of the present invention, and the operations thereof will be described in detail. 
     At first, a process of assembling the legs  30  to the base  20  of the washing machine  1  will be described. The lock nut  36  is assembled at the bolt unit  32  of the leg  30 , and the top of the bolt unit  32  is assembled at the through-hole  20 A of the base  20 . That is, if the bolt unit  32  of the leg  30  is rotated, the top of the bolt unit  32  is inserted into the through-hole  20 A and penetrates the through-hole  20 A to the top of the through-hole  20 A. If the bolt unit  32  of the leg  30  is screwed in the through-hole  20 A at a predetermined height, the lock nut  36  of the bolt unit  32  is closely attached at the bottom surface of the base  20  by rotating the lock unit  36 . After the legs  30  are installed, the adhesive  38  is coated on the upper outer circumference of the bolt unit  32  that penetrates the through-hole  20 A and the fixing nut  40  is screwed until the adhesive applied part of the bolt unit  32  is reached. Therefore, the fixing nut  40  is fixed at the top of the bolt unit  32  by the adhesive  38 . 
     The coating position of the adhesive  38  is a position corresponding to the through-hole  20 A when the legs  30  are unscrewed until the maximum unscrew height of the legs  30  that stably support the washing machine  1 . It is possible to coat the adhesive  38  between the bolt unit  32  and the fixing nut  40  after the fixing nut  40  is screwed at the bolt unit  32 . 
     Hereinafter, a process of adjusting the height of the leg  30  will be described. The washing machine  1  is horizontally balanced and installed at a predetermined height that enables a user to conveniently use the washing machine by properly adjusting the heights of the legs  30  according to the installation conditions of the washing machine  1 . That is, the bolt units  32  are inserted in the through-holes by rotating the legs  30  assembled in the through-holes  20 A of the base  20 . Or, the bolt units  32  are drawn out from the through-holes by rotating the legs  30 . The installation height of the washing machine  1  is adjusted and the washing machine  1  is balanced horizontally by properly inserting or drawing out the bolt unit  32 . 
     If the legs  30  are over unscrewed from the through-holes  20 A when the heights of the legs  30  are adjusted, the fixing nut  40  is caught at the top of the through-hole  20 A, thereby restricting the legs  30  from being excessively drawn out. Therefore, the fixing nut  40  prevents the legs  30  from being completely separated from the through-holes  20 A of the base  20  or prevents the legs  30  from being excessively unscrewed more than a predetermined height. 
       FIG. 4  is a side cross-sectional view of an assembling structure of a base and a leg of a washing machine according to another embodiment of the present invention, and  FIG. 5  is a cross-sectional view of  FIG. 4  taken along the line A-A. Like reference numerals denote like elements in  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5 . Hereinafter, the washing machine according to another embodiment will be described based on feature elements thereof, which are different from that shown in  FIG. 2  and  FIG. 3 . 
     Referring to  FIG. 4  and  FIG. 5 , the over-unscrew prevention member  140  includes a snap ring  140  disposed at the upper part of the bolt unit  132  of the leg  30  that penetrates the through-hole  20 A of the base in the washing machine according to another embodiment unlike the washing machine shown in  FIG. 2  and  FIG. 3 . The snap ring  140  is a member formed in a shape of surrounding an external circumference of the bolt unit  132 . The snap ring  140  is caught at the top of the through-hole  20 A to limit the maximum unscrew height of the leg  30  when the leg  30  is excessively unscrewed. 
     The snap ring  140  may include an O-ring, a C-ring, and an E-ring. Hereinafter, the snap ring  140  will be described as the E-ring. 
     The bolt unit  132  includes a mounting groove  133  formed in a corresponding shape of the snap ring  140  along the external circumference of a part where the snap ring  140  is mounted. That is, if the snap ring  140  is an E-ring, the mounting groove  133  is formed along the external circumference of the bolt unit  132  in a corresponding shape of the E-ring. A rotation prevention groove  133 A is formed in the mounting groove  133  to receive a protrusion  140 A projected from the inner circumference of the E-ring. 
     Since the snap ring  140  is mounted and fixed at the mounting groove  133  of the bolt unit  132  at once, it is more convenient that the fixing nut  40  shown in  FIG. 2  and  FIG. 3 . Also, it is easy to replace the snap ring  140  assembled at the mounting groove  33  of the bolt unit  132 . 
       FIG. 6  is a side cross-sectional view of an assembling structure of a base and a leg of a washing machine according to another embodiment of the present invention, and  FIG. 7  is a side exploded view of the assembling structure of  FIG. 6 . Like reference numerals denote like elements in  FIG. 2 ,  FIG. 3 ,  FIG. 6 , and  FIG. 7 . Hereinafter, the assembling structure of a base and legs according to another embodiment will be described based on feature elements thereof, which are different from that shown in  FIG. 2  and  FIG. 3 . 
     Referring to  FIG. 6  and  FIG. 7 , the washing machine according to another embodiment includes a base bracket  244  having mounting holes  244 A at the bottom of the through-hole  220 A of the base  220  and an over-unscrew prevention member  240  formed at the top of the bolt unit  32  that penetrates the mounting hole  244 A, which is caught at the base bracket  244  when the leg  30  is excessively unscrewed unlike the washing machine shown in  FIG. 2  and  FIG. 3 . 
     The base bracket  244  is a plate member made of metal, which is disposed at bottom surfaces of four corners of the base  220  in order to more stably dispose the legs  30  at the base  220 . The base bracket  244  includes an assembling hole  244 A formed at a position communicated with the through-hole  220 A to receive the bolt unit  32 . A female screw is formed at the inside circumference surface of the assembling hole  244 A to be screwed with an male screw of the bolt unit  32 . 
     The over unscrew prevention member  240  is a fixing nut fixed at the top of the bolt unit  32  that penetrates the assembling hole  244 A to be caught at the top of the base bracket  244  when the leg  30  is excessively unscrewed. That is, the fixing nut  240  is caught at the top of the base bracket  244  when the leg  30  is unscrewed more than the maximum height that stably supports the washing machine  1 , thereby limiting the legs  30  to be over-unscrewed. The fixing nut  240 , like the fixing nut  40  shown in  FIG. 2  and  FIG. 3 , is fixed at the bolt unit  32  using the adhesive  38  after the fixing nut  240  is assembled at a predetermined position of the bolt unit  32 . 
     Meanwhile, a receiving groove  220 B is formed at the bottom of the through-hole  220 A to receive the fixing nut  240  in order to allow the fixing unit  240  to move in a up and down direction without being interfered. The height of the receiving groove  220 B in the up and down direction is formed to be longer than the height variation of the washing machine that is adjusted by the leg  30 . 
     The foregoing exemplary embodiments and aspects of the invention are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. Also, the description of the exemplary embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art. 
     That is, the over unscrew prevention member is not limited to the fixing nut and the snap rings, and various type of members having a stopper function can be used. Also, the over unscrew prevention member may be caught at other parts as well as the through-hole of the base of the base bracket. 
     As described above, the bolt unit of the leg is height-adjustably assembled at the base, and the bolt unit of the leg includes the over-screw prevention member that caught by the base. Therefore, the washing machine according to an embodiment of the present invention can prevent legs from being over unscrewed or from being completely separated from the base when the legs are adjusted in height. 
     Since the washing machine according to an embodiment of the present invention can prevent the legs from being separated or from being excessively unscrewed, the operability of installing the washing machine is improved, and it can reduce vibration and noise generated from the washing machine when the legs are excessively unscrewed from the base.