Patent Abstract:
A washing machine includes a washing machine cabinet. A wash basket is mounted within the washing machine cabinet. A first agitator is mounted in the basket for rotation about a first agitator axis that extends in a direction different from the rotational axis of the wash basket. First agitator includes a first helical rib thereon for engaging and agitating the materials to be washed within the wash basket. A second agitator with a second helical rib may also be contained within the wash basket.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to a washing machine agitator having a helical rib and a method for using same.  
           [0002]    U.S. Pat. Nos. 5,829,277 and 6,220,063 both disclose a washing machine having a spherical basket for containing the fabrics to be washed. In the spherical basket are a pair of circular concave agitators nested against the opposite side walls of the spherical agitator basket.  
           [0003]    In order to achieve satisfactory cleaning of the fabrics being washed, it is desirable to achieve “turn over” of the fabrics being washed. The two agitators accomplish this by lifting the fabrics and causing them to be dropped downwardly towards the center of the washing basket. It is therefore desirable to provide agitators having the capability of lifting the fabrics during their rotation so that the fabrics are lifted up and dropped down the center to achieve the turn over necessary for satisfactory cleaning.  
           [0004]    Therefore a primary object of the present invention is the provision of an improved washing machine agitator having a helical rib.  
           [0005]    A further object of the present invention is the provision of a washing machine agitator having a helical rib which commences at an inner central point adjacent the rotational axis of the agitator and progresses helically and radially outwardly therefrom to an outer edge.  
           [0006]    A further object of the present invention is the provision of a spiral rib or baffle which smoothly engages the fabrics near the center of rotation of the pan and as the pan rotates the engagement point increases in radius.  
           [0007]    A further object of the present invention is the provision of a washing machine agitator having a helical rib or baffle that gives the fabrics being washed a smooth application of force to turn the load over with a minimum of tangling.  
           [0008]    A further object of the present invention is the provision of a washing machine agitator having a helical rib with two tapered surfaces which are joined along a helical ridge, one of the surfaces having a sharper angle of inclination than the other of the surfaces.  
           [0009]    A further object of the present invention is the provision of an improved washing machine agitator that is economical to manufacture, durable in use, and efficient in operation.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    The foregoing objects may be achieved by a washing machine comprising a washing machine cabinet. A wash basket is mounted within the washing machine cabinet for rotation about a wash basket axis. The wash basket includes an opening for placing materials to be washed within the wash basket.  
           [0011]    A first agitator is mounted in the basket for rotation about a first agitator axis that extends in a direction different from the wash basket axis. The first agitator includes a first helical rib thereon for engaging and agitating the materials to be washed within the washing basket when the first agitator is rotating about the first agitator axis.  
           [0012]    According to another feature of the invention, a second agitator is mounted within the basket for rotation about a second agitator axis extending in a direction different from the wash basket axis and the first agitator axis. The second agitator includes a second helical rib thereon for engaging and agitating the materials to be washed within the wash basket when the second agitator is rotating about the second agitator axis.  
           [0013]    According to another feature of the invention the first and second agitators each include a concave surface and the first and second helical ribs protrude from the concave surfaces of the first and second agitators respectively.  
           [0014]    According to another feature of the invention an agitator drive mechanism is connected to the first and second agitators for driving first and second agitators in opposite rotational directions.  
           [0015]    According to another feature of the present invention, the first and second helical ribs extend in first and second helical directions that are opposite to one another.  
           [0016]    According to another feature of the present invention each of the first and second helical ribs commence adjacent the first and second agitator axes respectively and extend in an outward radial helical direction therefrom.  
           [0017]    According to another feature of the present invention, the basket includes a concave interior surface and each of the first and second agitators include a convex surface opposite from the concave surface thereof. The convex surfaces of the first and second agitators face toward the concave interior surface of the basket.  
           [0018]    According to the method of the present invention, the fabrics being washed are lifted with the first and second helical ribs on the first and second agitators during rotation of the first and second agitators about the first and second agitator axes respectively. The helical ribs then drop the fabrics after they lift the fabrics whereby the fabrics will turn over and fall into the center portion of the basket.  
           [0019]    According to another feature of the method of the present invention, the first and second agitators are rotated in first and second opposite rotational directions.  
           [0020]    According to another feature of the method of the present invention, the rotational directions of the first and second agitators are reversed.  
           [0021]    According to another feature of the present invention, each of the first and second helical ribs include first and second side walls which angle toward one another and are joined together at an elongated helical rib. The first side wall has a first angle of inclination and the second side wall has a second angle of inclination that is steeper than the first angle of inclination. The method further comprises rotating the first and second helical ribs about the first and second agitator axes respectively in a rotational direction that causes the first side wall of the first and second helical ribs to engage and lift the fabrics.  
           [0022]    According to another feature of the present invention the rotational directions of the first and second helical ribs are reversed so that the second side walls of the first and second helical ribs engage and lift the fabrics. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0023]    [0023]FIG. 1 is a perspective view of the washing machine of the present invention.  
         [0024]    [0024]FIG. 2 is a vertical sectional view of the washing machine shown in FIG. 1.  
         [0025]    [0025]FIG. 3 is a perspective detail showing one of the agitators and the gear mechanism for rotating the agitator.  
         [0026]    [0026]FIG. 4 is a perspective view of one of the agitators of the present invention.  
         [0027]    [0027]FIG. 5 is a perspective view of the second of the agitators of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    Referring to the drawings the numeral  10  generally designates the washing machine of the present invention. Washing machine  10  includes a cabinet  12 , a control panel  14 , an access opening  15  (FIG. 2), and a door  16  which is hinged to move from an open to a closed position over the access opening  15 .  
         [0029]    Mounted within the lower end of cabinet  12  on a web  23  is a reversible motor  18  of conventional construction. Motor  18  has an output shaft  20  which extends upwardly through a bearing  22  in the web  23 . Motor  18  is attached to the web  23  by brackets  24 . Shaft  20  extends upwardly through a clutch  26  shown schematically in FIG. 2. Clutch  26  is adapted to respond to rotation of the shaft  20  in a first direction to drive a hub  34  which is connected to a spherically shaped basket  40 . Rotation of the shaft  20  in the opposite direction disengages the clutch and permits the shaft  20  to rotate independently of hub  34 .  
         [0030]    A tub  28  includes at its lower end a basin  30  for holding washing fluid. Extending upwardly from basin  30  is a spherically shaped lower tub portion  31 . The tub  28  extends upwardly to the top of basket  40  and terminates at an upper edge  32 . A tub cover  33  is attached to the upper edge  32  and extends inwardly over a portion of the top opening  41  of basket  40 . The tub cover  33  is cooperable with access opening  15  for providing an access into basket  40 .  
         [0031]    Hub  34  includes a central bore  36  which receives output shaft  20 . Output shaft  20  is attached at its upper end to a drive gear  38 .  
         [0032]    Hub  34  extends through the basin  30  by way of rotary seal arrangement shown schematically at  43  in FIG. 2, and is attached to the basket  40  which includes a spherical portion  42  and a gear box portion  44  at its lower end. Extending over the top of the gear box portion  44  is a curved wall  46  which forms an extension of the spherically shaped walls of spherical portion  42 . Curved wall  46  includes a first gear hole  48  and a second gear hole  50  therein. The space below the curved wall  46  comprises a gear box chamber  52  for housing the gear drive to be described hereafter.  
         [0033]    Basket  40  includes a plurality of perforations or apertures  54  in its spherically shaped walls  42  for permitting fluid communication between the interior of basket  40  and the tub  28 . Thus as fluid is introduced into the basket  40 , the fluid flows through the apertures  54  and enters the tub  28  also. As further depicted in FIG. 2 the web  23 , drive motor  18  and the washing assembly are shown suspended from the inside of cabinet  12  by a conventional hung strut suspension system  25  which is of known construction and does not comprise part of the instant invention.  
         [0034]    Agitators or lifters  56 ,  58  each include a circular peripheral rim  60  and a circular gear  62  which extends circumferencially around the back side of the rim  60 . Agitators or lifters  56 ,  58  are each rotatably mounted to the basket  40  by an agitator mount assembly  64 . The agitator mount assembly  64  is shown and described in U.S. Pat. No. 6,220,063, and is adapted to permit the agitators  56 ,  58  to rotate about the axes identified by the numerals  116 ,  118  respectively.  
         [0035]    The individual structure of agitator  56  is shown in FIG. 4 and of agitator  58  is shown in FIG. 5. Each agitator  56 ,  58  includes a concave surface  66  (FIG. 2) which is presented inwardly toward the interior of the tub  40  (FIG. 2). At the center of the concave surface  66  is a central bulge  68 , and commencing from this central bulge is a helical rib or baffle  70 . Each helical rib  70  includes a central starting point  72  which commences adjacent the rotational axes  116 ,  118  (FIG. 2) respectively of agitators  56 ,  58 . The helical rib or baffle  70  progresses in an outward radial direction and also in a helical direction to an outer peripheral end  74  which is located adjacent the rim  60  of the agitators  56 ,  58 . Each helical rib  70  includes a first wall  76  and a second wall  78  which are tapered toward one another and which join together at a helical ridge  80 . As can be seen in FIG. 2 the first wall  76  is inclined at a less steep angle of inclination than the second wall  78 . As can be seen in FIGS. 2, 4 and  5  the ridge  80  commences in the center bottom of agitators  56 ,  58 , and progresses upwardly to the approximate level of rim  60  of agitators  56 ,  58 . Ridge  80  also progresses in a spiral or helix from the center to the outer rim  60  of agitators  56 ,  58 .  
         [0036]    A pair of spaced apart wedges  81  are positioned on the outer edge of each agitator  56 ,  58  as best seen in FIGS. 4 and 5. Each wedge has a steep surface  83  and a less steep surface  85 . The steep surfaces  83  of wedges  81  are facing toward the more steep wall  78  of helical rib  70 . These wedges  81  facilitate tumbling of small loads of fabric. Each of the agitators  56 ,  58  is provided with a plurality of holes  87  that permit flow through of washing fluid.  
         [0037]    Each of the agitators  56 ,  58  includes a convex back surface  82  which is opposite from the concave surface  66 . The convex surface  82  nests against the concave surface  84  of spherical basket  40 . The helical direction of the first agitator  56  commences at the center and progresses outward in a clockwise helical direction as viewed in FIG. 4. The helical shape of the rib  70  in the agitator  58  is in the opposite direction, commencing at the center and progressing in a counterclockwise direction toward the outer radial rim  60 .  
         [0038]    The spinner rotational position is random. The agitators  56 ,  58  preferably rotate in a cooperative rotational direction to cause the clothes load to tumble in one direction as indicated by arrows  86 ,  88  in FIGS. 4 and 5 respectively. When rotating in this direction the less steep walls  76  of the two helical ribs engage the fabrics  134  being washed and lift them upwardly as shown in FIG. 2. At the top of the rotational cycle, the fabrics  134  are dropped downwardly in a central direction, and as they are dropped they turn over in the direction indicated by arrows  120 ,  122 . This creates the turnover necessary in order to adequately clean the fabrics. It is possible however, to reverse the direction of the rotational movement of the agitators  56 ,  58  so that the steeper wall  78  engages the fabrics and lifts them. This imparts a more aggressive cleaning action. If desired, the agitators  56 ,  58  can initially be operated in one rotational direction and then reversed.  
         [0039]    Also, the relative positions of the helical ribs  70  in agitators  56 ,  58  are preferably set so that agitator  58  points at 12 o&#39;clock and the agitator  56  points at 6 o&#39;clock. This places the two helical ribs  70 , 180° out of phase with one another and results in further agitation of the fabrics for improved cleaning.  
         [0040]    Referring to FIGS. 2 and 3, a gear assembly  92  is housed within the gear box chamber  52  and includes a first driven gear  94  which directly engages the annular teeth of the drive gear  38 . First driven gear  94  is connected to a first agitator gear  96 . An idler gear  100  in turn engages gear  104  which has a second agitator gear  106  on its upper surface.  
         [0041]    In operation shaft  20  drives gear  38  in a clockwise direction indicated by arrow  108  (FIG. 3). This rotates gears  94 ,  100  in the directions shown by arrows  110 ,  114  respectively. Rotation of gear  94  causes similar rotation of the first agitator gear  96  in the direction indicated by arrow  112 . The first agitator gear  96  engages the teeth of circumferencial gear  62  on the back of peripheral rim  60  of agitator  56 . This causes rotation of the agitator  56  about its axis formed by the agitator mount assembly  64  in the direction shown by arrow  86 .  
         [0042]    Agitator gears  96 ,  106  rotate in opposite directions, thereby causing the agitators  56 ,  58  also to rotate in opposite directions. Alternatively, gearing can be provided to cause the agitators  56 ,  58  to rotate in the same direction if desired or to reverse the rotational direction of agitators  56 ,  58 .  
         [0043]    As can be seen in FIG. 2 the water or washing fluid level  126  is at approximately the level of the agitator mounts  64 . The rotation of the two agitators  56 ,  58  creates a tumbling action of the fabrics being washed within the washing basket  40 . This tumbling action is facilitated by the helical ribs or baffles  70 .  
         [0044]    The. helical ribs  70  of the present invention provide an improved washing capability. The tumbling action provided by the helical ribs  70  during rotation of the agitators  56 ,  58  is a gentle action that minimizes damage and wear to delicate fabrics.-Furthermore, the helical ribs  70  cause a lifting of the washing fluid and improve the cleaning of the fabrics within the basket.  
         [0045]    After the washing cycle has been completed, motor  18  is reversed and the reverse rotation of shaft  20  causes the clutch  26  to engage with the hub  34 , thereby causing the basket  40  to rotate for its spin cycle. During the spin cycle the washing fluid passes outwardly through apertures  54  due to centrifugal force. The fluid within tub  28  is drained away.  
         [0046]    In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, these are used in a generic and descriptive sense only and not for purposes of limitation. Changes in the form and the proportion of parts as well as in the substitution of equivalents are contemplated as circumstances may suggest or render expedient without departing from the spirit or scope of the invention as further defined in the following claims.

Technology Classification (CPC): 3