Abstract:
An appliance is provided with a display system for use in connection with leveling the appliance. The system includes an accelerometer used in connection with an electronic controller to sense the degree to which the appliance is not level. Signals from the accelerometer are sent to a CPU which regulates a visual depiction on a display provided on the appliance. Adjustments made to alter the leveling condition of the appliance are also relayed to CPU, thereby updating the display and conveying when the appliance is suitably level. The system components can also be used to regulate other appliance operations.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention pertains to the art of appliances, and more particularly, to an appliance having a display system adapted to show a leveling condition of the appliance.  
           [0003]    2. Discussion of the Prior Art  
           [0004]    Various types of appliances are commonly placed in a wide range of environments, both in the business and domestic markets. For proper operation, many appliances must be supported in a level condition. However, when such appliances are installed, they are often supported on floors or foundations which are not perfectly flat or level. Nonetheless, it is critical that the appliance be mounted in a level and stable condition in order to function properly. This requirement can extend to a wide range of commonly known appliances, including clothes washing machines, clothes dryers, dishwashers and refrigerators.  
           [0005]    For instance, the leveling and stabilizing of a washing machine are important in connection with the overall operation of the machine. A washing machine which is not level and stable will rock during operation and be more likely affected by unbalanced loads within the washing machine, particularly during an extraction cycle. Indeed, unlevel washing machines have been known to rock back and forth to the point that they “walk” across a laundry room floor. Such motion is intolerable and numerous proposed solutions to this problem have heretofore been presented.  
           [0006]    Typically, appliances are provided with adjustable support feet which can be selectively extended or retracted. During installation, a technician can adjust each of the feet individually until the machine is level. Most often, such adjustments are made either by delivery personnel through merely visual inspection or, alternatively, the use of a carpenter&#39;s level. Obviously, the visual approach is not very accurate and requiring the installer to carry additional tools, such as a level, is also not desirable. In addition, even with the use of a level, various leg adjustment iterations are generally necessary, in combination with periodic shifting of the level, to achieve a final level condition.  
           [0007]    Based on the above, there exists a need in the art of appliances for a system which can be used to readily convey a leveling condition of the appliance to an installer or user thereof. Specifically, there exists a need for a leveling system which is integrated into the appliance and incorporates a display that visually represents the level condition of the appliance.  
         SUMMARY OF THE INVENTION  
         [0008]    An appliance constructed in accordance with the present invention incorporates a display system for visually representing a leveling condition of the appliance. Preferably, the leveling display system incorporates a two axis accelerometer used to determine if the machine is level and an LCD display which shows the information obtained from the accelerometer. In accordance with a preferred embodiment of the invention, the appliance includes a liquid crystal display (LCD) having a bubble icon represented on the LCD in relation to a number of concentric circles to convey the leveling condition of the appliance in both front to back and side to side directions. In practice, signals from the two axis accelerometer is sent to a controller of the appliance, whereupon the controller interprets the signals and appropriately alters the display.  
           [0009]    In use, when installing an appliance, the installer enters a special control mode through the display such that the level icon arrangement is visually illustrated. Based on the graphic representation provided, the installer can readily determine which of various leveling legs of the appliance need to be adjusted. The installer can continue to adjust one or more of the legs, while getting constant feedback through the display, until a desired leveling condition is reached. After initial appliance installation, information from the same accelerometer can be advantageously used to convey whenever a subsequent unlevel condition, as well as other appliance conditions, arises. For instance, in the case of a clothes washing machine, an actual or incipient unbalance, a starving drain pump, or an excessive vibration condition can be sensed, with signals being relayed to the controller for suitably altering the operation of the machine and/or providing a visual warning to the user of the appliance.  
           [0010]    Additional objects, features and advantages of the invention will become more readily apparent from the following detailed description of preferred embodiments of the invention, when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a partially cut away, perspective view of a washing machine incorporating a leveling display system constructed in accordance with the present invention;  
         [0012]    [0012]FIG. 2 is an exploded view of the various internal components of the washing machine of FIG. 1;  
         [0013]    [0013]FIG. 3 is a cross-sectional view of the internal components of the washing machine of FIG. 2 in an assembled state; and  
         [0014]    [0014]FIG. 4 is an enlarged view of the leveling display of FIG. 1.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0015]    For purposes of describing the invention, reference will be made to the application of the invention in a laundry appliance. However, as will become readily apparent below, the invention is applicable to a wide range of appliances. Therefore, with initial reference to FIG. 1, an automatic horizontal axis washing machine incorporating the display system of the present invention is generally indicated at  2 . In a manner known in the art, washing machine  2  is adapted to be front loaded with articles of clothing to be laundered through a tumble-type washing operation. As shown, automatic washing machine  2  incorporates an outer cabinet shell  5  provided with a front door  8  adapted to extend across an access opening  10 . Front door  8  can be selectively pivoted to provide access to an inner tub or spinner  12  that constitutes a washing basket within which the articles of clothing are laundered.  
         [0016]    As is known in the art, inner tub  12  is formed with a plurality of holes  15  and multiple, radially inwardly projecting fins or blades  19  are fixedly secured to inner tub  12 . Inner tub  12  is mounted for rotation within an outer tub  25 , which is supported through a suspension mechanism (not shown) within cabinet shell  5 . Inner tub  12  is mounted within cabinet shell  5  for rotation about a generally horizontal axis. Actually, the rotational axis is angled slightly downwardly and rearwardly as generally represented in FIG. 3. Although not shown, a motor, preferably constituted by a variable speed, reversible electric motor, is mounted within cabinet shell  5  and adapted to drive inner tub  12 . More specifically, inner tub  12  is rotated during both wash and rinse cycles such that articles of clothing placed therein actually tumble through either water, water/detergent or another washing fluid supplied within inner tub  12 . Given that inner tub  12  is provided with at least the plurality of holes  15 , the water or water/detergent can flow between the inner and outer tubs  12  and  25 . A pumping system (not shown) is provided to control the level of washing fluid within machine  2 , with one pump  30 , shown schematically in FIG. 3, particularly controlling the timed draining of the fluid from the outer tub  25 .  
         [0017]    The general manner in which the automatic washing machine  2  of FIG. 1 operates is well known in the art and is not considered an aspect of the present invention. Therefore, a full description of its operation will not be described here. However, for the sake of completeness, automatic washing machine  2  is also shown to include an upper cover  42  that provides access to an area for adding detergent, softeners and the like. In addition, an upper control panel  45 , including an LCD display screen  46 , is provided for manually establishing a desired washing operation in a manner known in the art.  
         [0018]    As best seen in FIGS. 2 and 3, in order to allow inner tub  12  to freely rotate within outer tub  25  during a given washing operation, inner tub  12  is spaced concentrically within outer tub  25 . This spacing establishes an annular gap  56  between the inner and outer tubs  12  and  25 . As will be discussed fully below, an axial gap is also created at the open frontal portions of inner and outer tubs  12  and  25 . During operation of washing machine  2 , the washing fluid can flow through gap  56  from inner tub  12  into outer tub  25 . In addition, small objects can also flow into the outer tub  25  through the axial gap. Unfortunately, it has been found in the past that some objects flowing through the axial gap can end up clogging or otherwise disrupting the normal operation of the pumping system, thereby leading to the need for machine repairs. In order to remedy this situation, it has been heretofore proposed to incorporate a flexible sealing device, generally indicated at  60  in FIGS. 1 and 3, which functions to bridge this gap between inner and outer tubs  12  and  25  to prevent such objects from flowing into the outer tub  25 . Further provided as part of washing machine  2 , in a manner known in the art, is a sealing boot  62  which extends generally between outer tub  25  and a frontal panel portion (not separately labeled) of cabinet shell  5 .  
         [0019]    Reference now will be made to FIGS. 2 and 3 in describing the preferred mounting of inner tub  12  within outer tub  25  and the arrangement of both sealing device  60  and sealing boot  62  as the tumble cycle feature of the present invention is related to the presence of one or more of these structural elements. Inner tub  12  has an annular side wall  61  and an open front rim  71  about which is secured a balance ring  75 . In the preferred embodiment, balance ring  75  is injection molded from plastic, such as polypropylene, with the balance ring  75  being preferably mechanically attached to rim  71 . Inner tub  12  also includes a rear wall  77  to which is fixedly secured a spinner support  79 . More specifically, spinner support  79  includes a plurality of radially extending arms  81 - 83  which are fixedly secured to rear wall  77  by means of screws  84  or the like. Spinner support  79  has associated therewith a driveshaft  85 . Placed upon driveshaft  85  is an annular lip seal  88 . Next, a first bearing unit  91  is press-fit onto driveshaft  85 . Thereafter a bearing spacer  93  is inserted upon driveshaft  85 .  
         [0020]    The mounting of inner tub  12  within outer tub  25  includes initially placing the assembly of inner tub  12 , balance ring  75 , spinner support  79 , lip seal  88 , first bearing unit  91  and bearing spacer  93  within outer tub  25  with driveshaft  85  projecting through a central sleeve  96  formed at the rear of outer tub  25 . More specifically, a metal journal member  99  is arranged within central sleeve  96 , with central sleeve  96  being preferably molded about journal member  99 . Therefore, driveshaft  85  projects through journal member  99  and actually includes first, second and third diametric portions  102 - 104 . In a similar manner, journal member  99  includes various diametric portions which define first, second and third shoulders  107 - 109 . Journal member  99  also includes an outer recess  111  into which the plastic material used to form outer tub  25  flows to aid in integrally connecting journal member  99  with outer tub  25 .  
         [0021]    As best shown in FIG. 3, the positioning of driveshaft  85  in journal member  99  causes each of annular lip seal  88 , first bearing  91  and bearing spacer  93  to be received within journal member  99 . More specifically, annular lip seal  88  will be arranged between first diametric portion  102  of driveshaft  85  and journal member  99 . First bearing unit  91  will be axially captured between the juncture of first and second diametric portions  102  and  103 , as well as first shoulder  107 . Bearing spacer  93  becomes axially positioned between first bearing unit  91  and second shoulder  108  of journal member  99 . Thereafter, a second bearing unit  114  is placed about driveshaft  85  and inserted into journal member  99 , preferably in a press-fit manner, with second bearing unit  114  being seated upon third shoulder  109 . At this point, a hub  117  of a spinner pulley  118  is fixedly secured to a terminal end of driveshaft  85  and axially retains second bearing unit  114  in position. Spinner pulley  118  includes an outer peripheral surface  120  which is adapted to be connected to a belt (not shown) driven in a controlled fashion by the reversible motor mentioned above in order to rotate inner tub  12  during operation of washing machine  2 . In order to provide lubrication to lip seal  88 , central sleeve  96  is formed with a bore  123  that is aligned with a passageway  124  formed in journal member  99 .  
         [0022]    Outer tub  25  has associated therewith a tub cover  128 . More specifically, once inner tub  12  is properly mounted within outer tub  25 , tub cover  128  is fixedly secured about the open frontal zone of outer tub  25 . Although the materials for the components discussed above may vary without departing from the spirit of the invention, outer tub  25 , balance ring  75  and tub cover  128  are preferably molded from plastic, while inner tub  12  is preferably formed of stainless steel. Again, these materials can vary without departing from the spirit of the invention. For example, inner tub  12  could also be molded of plastic.  
         [0023]    Outer tub  25  is best shown in FIG. 2 to include a plurality of balance weight mounting gusset platforms  132  and  133 , a rear mounting boss  136  and a front mounting support  137 . It should be realized that commensurate structure is provided on an opposing side portion of outer tub  25 . In any event, balance weight mounting platforms  132  and  133 , mounting boss  136 , mounting support  137  and further mounting boss  140  are utilized in mounting outer tub  25  within cabinet shell  5  in a suspended fashion. Again, the specific manner in which outer tub  25  is mounted within cabinet shell  5  is not considered part of the present invention, so it will not be described further herein. Outer tub  25  is also provided with a fluid inlet port  141  through which washing fluid, i.e., either water, water/detergent or the like, can be delivered into outer tub  25  and, subsequently, into inner tub  12  in the manner discussed above. Furthermore, outer tub  25  is formed with a drain port  144  which is adapted to be connected to the pump  26  for draining the washing fluid from within inner and outer tubs  12  and  25  during certain cycles of a washing operation.  
         [0024]    As best illustrated in FIG. 3, inner tub  12  is entirely spaced from outer tub  25  for free rotation therein. This spaced relationship also exists at the front ends of inner and outer tubs  12  and  25  such that an annular gap  146  is defined between an open frontal zone  147  of outer tub  25  and an open frontal portion  149  associated with balance ring  75 . It is through a lower section of gap  146  that washing fluid can also flow from within inner tub  12  to outer tub  25 . With this fluid flow, other items including buttons, hair pins and the like inadvertently placed in inner tub  12  with the clothes to be washed, can get into outer tub  25 . Typically, the pump  26  associated with drain port  144  is capable of managing certain objects without any problem. However, depending upon the size and number of the objects, the pump  26  may not be able to handle the objects, whereby the pump  26  will clog or at least the normal operation thereof will be disrupted.  
         [0025]    Because of this problem, the flexible sealing device  60  is mounted so as to bridge gap  146  between inner and outer tubs  12  and  25  and, specifically, between balance ring  75  and tub cover  128 . Gap  146  is required because of deflections between inner tub  12  and outer tub  25  during operation of washing machine  2 . Sealing device  60  bridges gap  146  to prevent small items from passing through, but sealing device  60  is flexible so as to accommodate changes in the size of gap  146  resulting from deflections during operation. Sealing device  60  includes a first seal portion  151  that is fixed or otherwise secured to a rear or inner surface  152  of tub cover  128  and a second, flexible seal portion  155 , such as brush bristles or a plastic film, which projects axially across gap  146  and is placed in close proximity and most preferably in sliding contact with a front or outer surface  156  of balance ring  75 . As is also known in the art, sealing boot  62  includes an inner annular end  162  which is fixed sealed to tub cover  128 , an outer annular end  164  which is fixed to the front cabinet panel (not separately labeled) of cabinet shell  5  and a central, flexible portion  166 . As perhaps best shown in FIG. 3, flexible portion  166  actually defines a lower trough  168 .  
         [0026]    Until this point, the basic structure of washing machine  2  as described above is known in the art and has been described both for the sake of completeness and to establish the need and advantages of the leveling display system of the present invention which will be detailed below. The present leveling display system is shown as a modification to washing machine  2  having the LCD display  46 . LCD display  46  can be used to operate washing machine  2  in accordance with the disclosure in copending U.S. patent application Ser. No. 09/741,067 filed Dec. 21, 2000 which is hereby incorporated by reference. In addition to the conventional parts of washing machine  2  as described above, the leveling display system includes an accelerometer  170  which may be mounted essentially anywhere within the washing machine  2 .  
         [0027]    As best represented in FIG. 4, display  46  is able to show a pattern, preferably in the form of a target icon, such as a bullseye, enabling a technician, installer or other user of washing machine  2  to discern whether or not the machine  2  is level, particularly when being installed. In the most preferred form of the invention, the pattern is represented by a series of concentric rings  172 - 175  as shown in FIG. 4, along with a moving dot  176  which essentially represents a “bubble” analogous to that found in a conventional liquid-type carpenter&#39;s level. Signals from accelerometer  170  are directed to a central processing unit (CPU)  177  incorporating specific circuits. More specifically, CPU  177  includes a level detection circuit  178  and an unbalance/pump starvation detection circuit  179 , along with several controls such as a display controller  181 , a tub drive controller  182 , cycle controls  184  and a control for pump  30 .  
         [0028]    As shown in FIG. 3, accelerometer  170  is preferably mounted to a rear wall of outer tub  25  of washing machine  2 . Accelerometer  170  is connected through a wire (not shown) to CPU  177 . In general, accelerometer  170  is a two axis accelerometer which can measure the tilting of machine  2 , either around a horizontal axis about which the tub  12  rotates or, alternatively, about an axis which is 90° relative thereto. Such an arrangement enables accelerometer  170  to determine whether washing machine  2  is tilted too far to the left or right, or front to back, as typically viewed from the front of machine  2  as seen in FIG. 1.  
         [0029]    Central processing unit  177  receives signals from accelerometer  170  and interprets them in several ways. Primarily CPU  177  uses a level detection circuit  178  in order to determine the amount of tilting in the machine  2  in the various directions mentioned above. In a preferred embodiment, this information is interpreted and sent to display controller  181  so that display  46  shows the numerous concentric circles  172 - 175 , along with dot  176  which may move relative to circles  172 - 175  to indicate how far machine  2  is off level. Ideally, when dot  176  aligns with the center of concentric circles  172 - 175 , machine  2  is perfectly level.  
         [0030]    In operation, a technician, installer or other user of washing machine  2  will select an icon initially represented in display  46  in order to have CPU  177  present the concentric circles  172 - 175  and bubble  176 , as opposed to standard control options which are normally depicted. Thereafter, feet  190  located at the bottom of cabinet shell  5  of washing machine  2 , as shown in FIG. 1, are manually adjusted until display  46  indicates that machine  2  is level. Of course, although only two manually adjustable feet  190 , which are threadably attached to cabinet shell  5 , are depicted, it should be clearly understood that a total of four feet  190 , two in the front and two in the rear of cabinet shell  5 , are preferably provided.  
         [0031]    It should be noted that accelerometer  170  can be used for numerous other functions within washing machine  2  besides just feeding signals to CPU  177  to be processed through level detection circuit  178  and display controls  181 . Rather, based on signals received by CPU  177  from accelerometer  170 , unbalance/pump starvation detection circuit  179  can determine whether machine  2  is unbalanced or exhibits an excessive vibration. In accordance with the invention, the presence of an unbalance condition is counteracted by reducing the rate at which basket  12  is being driven through tub drive controls  182  and/or altering the preset operating cycles of washing machine  2  through cycle controls  184 . For instance, if an unbalance condition is detected during the extraction phase of washing machine  2 , the rotational speed imparted to basket  12  is preferably, initially reduced. If this alteration does not alleviate the excessive balance condition, the operating cycle of washing machine  2  is then terminated through cycle controls  184 . Alternatively, cycle controls  184  can simply activate a visual or audible alarm so the user can take appropriate action.  
         [0032]    Additionally, CPU  180  and, more specifically, unbalance/pump starvation circuit  179  can also detect characteristic electrical signals from accelerometer  170  which indicate when drain pump  30  is starving, for example during water spinout. While unbalance condition noises are typically caused by cabinet hits from rotating basket  12  and other general vibrations, a starving pump causes vibrations from lack of water and the forcing of water back and forth in a drain hose. In accordance with the invention, accelerometer  170  relays to CPU  177  vibration signals indicative of pump noises which are objectionably high and indicative of classic pump starving conditions. Once CPU  177  senses that accelerometer  170  is conveying characteristic signals of pump starvation through circuit  179 , cycle controls  184  are preferably used to turn pump  30  off to avoid the pump starvation condition. Furthermore, when the water level is high enough to hit inner basket  12  and thus cause a characteristic vibration within washing machine  2 , cycle controls  184  function to turn drain pump  30  on again.  
         [0033]    Still further, accelerometer  170 , provided for use in leveling washing machine  2  in accordance with the invention, may also be used to find optimum speeds that provide a relatively low amount of vibration in washing machine  2 . A similar method of finding an optimal rotational speed for tub  12  to keep a washing machine vibration at a minimum can be found in U.S. Pat. No. 5,930,855 which is incorporated herein by reference.  
         [0034]    Based on the above description, it is readily apparent that the present invention provides a simple and inexpensive leveling display system which provides a convenient and effective manner to level an appliance to enhance the operation thereof. Additionally, the preferred embodiment provides an efficient way to effect further control of an appliance economically using certain parts of the leveling display system. In any event, although described with reference to a preferred embodiment of the invention as incorporated in a washing machine, it should be understood that the invention can also be utilized in various other types of appliances, including clothes dryers, dishwashers and refrigerators, all of which would exhibit enhanced operating performance when level. For example, for proper operation, a refrigeration circuit needs to be properly leveled such that the leveling display system could be advantageously employed in a refrigerator. Corresponding advantages are achieved in clothes dryers and dishwashers as well. In any event, various changes and/or modifications can be made to the invention without departing from the spirit thereof. Finally, it should be realized that other known devices for sensing a leveling condition can be employed in place of accelerometer  170 . Therefore, in general, the invention is only intended to be limited by the scope of the following claims.