Abstract:
A balance ring for an appliance is provided that has features to control fluid distribution particularly during certain critical speeds where large oscillatory motion created by an out of balance condition might otherwise cause the balance ring fluid to redistribute improperly. The balance ring can include an inner chamber that is in fluid communication with an outer chamber. The inner chamber can include baffles that impede the movement of fluid along the circumferential direction when e.g., the balance ring experiences large oscillatory motion.

Description:
FIELD OF THE INVENTION 
     The subject matter of the present disclosure relates generally to a balance ring for an appliance. 
     BACKGROUND OF THE INVENTION 
     During the operation of a washing machine, particularly during spin cycles, the machine can sometimes experience an extreme vibration. These vibrations can even cause displacement of the washing machine as it “walks” across a surface such as a floor. Typically, this event is due to the different shapes and densities of the clothing or other articles that are being washed which, after the washing cycle and draining the wash basket, can stick together and cause differences in the center of mass inside the wash basket. The vibration problem can also be caused by the introduction of relatively heavier articles into the wash basket such as e.g., shoes. 
     By way of example, after the washing cycle and draining of the washing liquid from the wash basket, the shoes or other, relatively heavier articles may be located on one side of the wash basket or in a manner that causes the center of mass of the combined wash basket and articles (such as the shoes, clothes, and other items being washed) to be off center. As the wash basket is rotated, particularly at high speeds, the off centering and centrifugal forces creates an imbalance that can generate undesired strain in the washing machine components, an undesirable level of noise, and/or “walking” of the appliance. In an extreme or prolonged situation, the imbalance created by the excessive vibration can also wear-out and damage the washing machine components. 
     As a result, in order to counter the out of balance wash load, various devices have been proposed. For example, washing machines have been equipped with balance rings, which are typically hollow rings placed on the top and sometimes bottom of the wash basket. Inside the ring (or toroid) a weight such as a fluid and/or movable metal objects such as e.g., solid balls have been inserted. During operation, the ring will act as a counterweight to the out of balance load of clothes because the fluid and/or solid balls will move to a position within the ring that counters the centrifugal forces created by the articles in the wash basket so as to balance the overall mass of the articles in the wash basket. 
     Thus, for balance rings that incorporate a fluid, during spinning of the wash basket the fluid must be able to redistribute so to act as a counterweight to an out of balance of mass of the articles in the wash basket. Sometimes, however, as the rotational speed of the wash basket increases during a spin cycle, one or more critical speeds (i.e. resonant modes) are reached. At these critical speeds, the translational motion of the balance ring can be severe enough distribute the fluid in a manner that prevents it from properly counteracting the out of balance wash load. In fact, the fluid may even be distributed in a manner that reinforces the tub motion. 
     BRIEF DESCRIPTION OF THE INVENTION 
     Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention. 
     The present invention provides a balance ring for an appliance with features to control fluid distribution particularly during certain critical speeds where motion created by an out of balance condition might otherwise cause the balance ring fluid to redistribute improperly. The balance ring can include an inner chamber that is in fluid communication with an outer chamber. The inner chamber can include baffles that impede the movement of fluid along the circumferential direction when e.g., the balance ring experiences translational motion. 
     For example, in one exemplary embodiment, the present invention provides a balance ring for an appliance. The balance ring defines radial and circumferential directions. The balance ring includes an outer chamber extending along the circumferential direction and an inner chamber also extending along the circumferential direction and positioned adjacent and radially inward of the outer chamber. A dividing wall is positioned between the outer chamber and the inner chamber. A plurality of openings are defined by the dividing wall and are spaced apart along the circumferential direction. The openings provide for fluid communication between the outer chamber and the inner chamber. A fluid is located in the outer chamber and the inner chamber. 
     In another exemplary embodiment, the present invention provides a washing machine appliance that includes a cabinet, a wash tub received within the cabinet; and a wash basket rotatably received within the wash tub. The wash basket has an exterior surface extending circumferentially around the wash basket. A motor is connected with the wash basket and configured for rotating the wash basket. A balance ring is connected to the wash basket and has radial and circumferential directions. The balance ring includes an outer chamber extending along the circumferential direction and an inner chamber extending along the circumferential direction and positioned adjacent and radially inward of the outer chamber. A dividing wall is positioned between the outer chamber and the inner chamber. A plurality of openings are defined by the dividing wall and are spaced apart along the circumferential direction. The openings provide for fluid communication between the outer chamber and the inner chamber. A fluid is located in the outer chamber and the inner chamber. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
         FIG. 1  provides a perspective view of an exemplary embodiment of a washing machine of the present invention. 
         FIG. 2  illustrates a cross-sectional view of the exemplary embodiment of  FIG. 1 . 
         FIG. 3  is cross-sectional, schematic view of an exemplary embodiment of a balance ring of the present invention as viewed from the top down. 
         FIG. 4  is another cross-sectional, schematic view of another exemplary embodiment of a balance ring of the present invention as viewed from the top down. 
         FIG. 5  is a perspective view of an exemplary embodiment of a balance ring with a cross-section provided to illustrate certain internal features. 
         FIG. 6  is another perspective view of the exemplary embodiment of  FIG. 5  ring with a cross-section provided to illustrate certain internal features. 
         FIG. 7  is a perspective view of a bottom portion of the exemplary embodiment of  FIG. 5 . 
     
    
    
     The use of the same or similar reference numerals in the figures indicates the same or similar features. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
       FIG. 1  is a perspective view an exemplary vertical axis washing machine  50  including a cabinet  52  and a top cover  54 .  FIG. 2  provides a cross-sectional, side view of the exemplary embodiment of  FIG. 1 . A backsplash  56  extends from cover  54 . A control panel  58  including a plurality of input selectors  60  is coupled to backsplash  56 . Control panel  58  and input selectors  60  collectively form a user interface input for operator selection of machine cycles and features, and in one embodiment, a display  64  indicates selected features, a countdown timer, and/or other items of interest to machine users. A lid  62  is mounted to cover  54  and is rotatable about a hinge (not shown) between an open position (not shown) facilitating access to a wash tub  78  located within cabinet  52 , and a closed position (shown in  FIG. 1 ) forming an enclosure over wash tub  78 . 
     A wash basket  76  is located within wash tub  78  in spaced apart relationship from tub  78 . Articles for washing are placed within basket  76 . A motor  80  is used to selectively spin wash basket  76  during various cycles of the appliance. Wash basket  76  includes a plurality of openings  70  that facilitate the movement of fluid in and out of basket  76  within wash tub  78 . When wash basket  76  is rotated at high speed during e.g., a spin cycle, openings  70  in wash basket  76  allow fluid to be wrung from the articles such as clothing located in basket  76 . 
     An agitation element such as agitator  72  with blades  74 , impeller, auger, or oscillatory basket mechanism, or some combination thereof is disposed in basket  76  to impart an oscillatory motion to articles and liquid in basket  76  using motor  80 . In different embodiments, agitation element  72  can include a single action element (i.e., oscillatory only), double action (oscillatory movement at one end, single direction rotation at the other end) or triple action (oscillatory movement plus single direction rotation at one end, singe direction rotation at the other end). As illustrated in  FIG. 2 , agitation element  72  is oriented to rotate about a vertical axis A. 
     Operation of machine  50  is controlled by a controller or processing device (not shown), that is operatively coupled to the user interface input or control panel  58  located on washing machine backsplash  56  (shown in  FIG. 1 ), which allows e.g., for user manipulation to select washing machine cycles and features. More particularly, in response to user manipulation of the user interface input, the controller operates the various components of machine  50  to execute selected machine cycles and features. 
     For example, in an illustrative embodiment, laundry items are loaded into basket  76 , and washing operation is initiated through operator manipulation of control input selectors  60  (shown in  FIG. 1 ). Wash tub  78  is filled with water and mixed with detergent to form a wash fluid, and contents of the basket  76  are agitated with agitation element  72  for cleansing of laundry items in basket  76 . More specifically, agitation element  72  is moved back and forth in an oscillatory back and forth motion. 
     After the agitation phase of the wash cycle is completed, wash tub  78  can be drained with a pump assembly (not shown). Laundry items are then rinsed and portions of the cycle repeated, including the agitation phase, depending on the particulars of the wash cycle selected by a user. One or more spin cycles may also be used. In particular, a spin cycle may be applied after the wash cycle and/or after the rinse cycle in order to wring wash fluid from the articles being washed. During a spin cycle, wash basket  76  is rotated at relatively high speeds. 
     While described in the context of a specific embodiment of vertical axis washing machine appliance  50 , using the teachings disclosed herein it will be understood that vertical axis washing machine appliance  50  is provided by way of example only. Other washing machine appliances having different configurations, different appearances, and/or different features may also be utilized with the present subject matter as well. 
     As previously described, the articles inside basket  76  can sometimes cause an imbalance leading to undesirable vibrations of machine  50  during operation. Accordingly, for this exemplary embodiment, washing machine  50  is equipped with exemplary balance rings  66  and  68  that operate to counteract imbalances in the wash load placed into wash basket  76 . Balance rings  66  and  68  are shown in cross section in  FIG. 2  but should be understood to extend circumferentially about wash basket  76 . For this exemplary embodiment, balance rings  66  and  68  are mounted to an exterior surface  82  of wash basket  76  and other techniques for positioning on basket  76  may also be used. Also, although shown with a balance ring positioned at both a top and bottom of wash basket  76 , it should be understood that only one such balance ring—particularly at the top of wash basket  76  as with balance ring  66 —may be used in other exemplary embodiments of the present invention. Balance rings  66  and  68  include features for controlling the movement of a fluid in such rings that offsets an imbalance of articles in wash basket  76 . 
     For example,  FIG. 3  provides a cross-sectional, schematic view of an exemplary embodiment of a balance ring  100  of the present invention as viewed from the top down. Balance ring  100  defines a radial direction as shown by arrow R and circumferential direction C. During operation of the washing machine  50  where wash basket  76  is in spin mode, balance ring  100  rotates about the axis of rotation A. along circumferential direction C. 
     Balance ring  100  includes an outer chamber  102  that extends uninterrupted along circumferential direction C and contains a fluid such as e.g., a solution of calcium chloride and water. An inner chamber  104  also extends along circumferential direction C is positioned adjacent and radially inward of outer chamber  102 . Inner chamber  104 , however, is interrupted by a plurality of baffles  108  that are intermittently spaced from each other along the circumferential direction C. Baffles  108  divide inner chamber  104  into multiple sections  109  that are fully separated from each other along the circumferential direction except for openings  113 . A dividing wall  106  is positioned between the inner chamber and the outer chamber and separates the two along the circumferential direction. Openings  113  allow fluid to pass only a low speeds. Openings  113  also allow air to pass between chambers  104 . In other exemplary embodiments of the invention, baffles  108  may be provided without openings  113 . 
     As further illustrated in  FIG. 3 , a plurality of apertures or openings  112  are defined by dividing wall  106 . Apertures  112  are spaced apart along the circumferential direction and, for exemplary embodiment, are positioned equidistant from a pair of baffles  108  with one aperture  112  located in each section  109 . However, as will be understood using the teachings disclosed herein, a different number and positioning for apertures  112  may be used in each section  109 . For the exemplary embodiment shown in  FIG. 3 , a total of 8 sections  109  are shown. However, a different number of sections  109  may be used. For example, 8 to 12 sections may be used in balance ring  100 . 
     During operation, the spinning of balance ring  100  about axis A causes centrifugal forces to act on fluid  110  in the direction indicated by arrows CF. As a result, fluid  110  may pass from inner chamber  104  to outer chamber  102  by passing through apertures or openings  112 . Fluid  110  can also move in the circumferential direction C along outer chamber  103  and redistribute between sections  109  of inner chamber  104  as shown by arrow F in order to counter an imbalance in a load of articles placed in the wash tub  78 . However, baffles  108  prevent the redistribution of fluid along the circumferential direction C by moving between sections  109  of inner chamber  104 . As a result, the movement of fluid along circumferential direction C and between sections  109  must occur through outer chamber  102 . 
     By determining the size of outer chamber  102  relative to inner chamber  104  and the size openings  112 , the ability of the fluid  110  to move between sections  109  can be carefully controlled. More specifically, when oscillatory motion (e.g., along radial direction R) occurs as the spinning of balance ring  100  reaches certain critical speeds, the ability of fluid  110  to redistribute between sections  109  is hampered or delayed. As such, fluid  110  cannot redistribute in a manner that reinforces the oscillatory forces so as to further exacerbate an out of balance condition. However, fluid  110  can still redistribute as shown by arrow F so as to gradually offset in imbalance condition. 
       FIG. 4  provides a cross-sectional, schematic view of another exemplary embodiment of balance ring  100  of the present invention as viewed from the top down. The embodiment of  FIG. 4  is similar to  FIG. 3  except for differences in the width of baffles  108  along radial direction R. As shown baffles  108  extend only partially between dividing wall  106  and inner wall  107  so that inner chamber  104  is divided into partial sections  111 . As such, during spinning of balance ring  100 , fluid  110  can redistribute between partial sections  111  in a manner as previously described with regard to the embodiment of  FIG. 3 . However, fluid  110  can also redistribute by spilling over a baffle  108  as shown in the lower part of  FIG. 4 . Thus, for the exemplary embodiment of a balance ring  100  shown in  FIG. 4 , the movement of fluid  110  during translational motion at critical rotation speeds is still impeded so as to prevent undesirable reinforcement of the out of balance condition—yet a flow of fluid between partial sections  111  is still allowed so as to provide for a redistribution of fluid  110  that can counter an out of balance condition. 
     Another exemplary embodiment of a balance ring  200  of the present invention is illustrated using  FIGS. 5 through 7 .  FIGS. 5 and 6  provide different perspective views with a cross-section to illustrate certain internal features while  FIG. 7  provides a perspective view of a part of a lower portion  218  of balance ring  200 . 
     For this exemplary embodiment, balance ring  200  is constructed from lower portion  218  and upper portion  216  that are joined together. Upper portion  216  includes a plurality of tongues  220  separated by a groove  222 . Similarly, lower portion  218  include a plurality of tongues  224  separated by a groove  226 . Together, such features combine in a complementary manner as shown in  FIGS. 6 and 7  to secure upper and lower portions  216  and  218  together. Tongues  220  and  224  create a dividing wall  206  along one side of balance ring  200  so as to separate inner chamber  204  and outer chamber  202 . An opening  212  allowing fluid to pass between inner chamber  204  and outer chamber  202  is created in part by a groove  230  formed in the top edge  228  of a tongue  224 . A baffle  208  divides inner chamber  204  into partial sections  211 . Outer chamber  202 , inner chamber  204 , baffle  208 , and openings  212  function in a manner similar to that previously described with regard to the exemplary embodiment of  FIG. 4 . 
     For the exemplary embodiment of  FIGS. 5 through 7 , balance ring  200  is also provided with a radially innermost chamber  214 . Radially innermost chamber  214  is completely sealed from inner chamber  104  and outer chamber  102 . By way of example, radially innermost chamber  214  could be provided with a fluid to provide additional weight to counter an imbalanced load of articles in the wash basket. 
     The present invention is not limited to the particular construction of balance ring  200 . Using the teachings disclosed herein, it will be understood the other configurations of a balance ring may be applied and such balance ring may be used on washing machines as well as other appliances for which a counter for an out of balance condition of a rotating component is desired. This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.