Abstract:
A latch assembly includes a handle, a handle retainer, and a keeper. The keeper includes a biasing mechanism and a head comprising a catch, a lock release projection, and a switch actuator. The keeper biasing member configured to facilitate engaging the catch with the door. The handle biasing member configured to facilitate maintaining the handle in a first position. The handle includes a contact surface slidingly coupled to the lock release projection to facilitate coupling the door to the tub assembly.

Description:
BACKGROUND OF INVENTION  
         [0001]    This invention relates generally to door latches, and more particularly, to methods and apparatus for securing an appliance door in a closed position.  
           [0002]    At least some known dishwashers include a hinged door and a latch assembly that prevents the dishwasher from operating unless the door is latched in a closed position. To facilitate dishwasher operation, the latch assembly performs several different functions, including, securing the door to the tub assembly in a closed position, interrupting dishwasher operations when the door is opened, and restoring dishwasher operations when the door is returned to a closed position.  
           [0003]    To perform such functions, at least some known latch assemblies include a plurality of stationary and moving components which interact with each other. However, because of the number and complexity of components, assembly of such latch assemblies may be a costly and time consuming process.  
         SUMMARY OF INVENTION  
         [0004]    In one aspect, a latch assembly includes a keeper which includes a biasing member and a head portion extending from the biasing member. The head portion includes a catch and a lock release projection. The biasing member is configured to bias the catch for engagement with the door. The handle includes a contact surface in slidable contact with the lock release projection. The handle is selectively operable to unsecure the door from the tub assembly. A handle retainer couples the handle to the door.  
           [0005]    In another aspect, a method for assembling a door latch assembly for a dishwasher is provided. The latch assembly is configured to secure a dishwasher door to a dishwasher tub assembly. The method includes providing a handle, providing a handle retainer, connecting the handle to the handle retainer, and installing a keeper such that the keeper is slidably coupled to the handle.  
           [0006]    In a further aspect, a dishwasher includes a tub assembly, a door hingedly coupled at a first edge to the dishwasher, and a latch assembly for securing the dishwasher door to the dishwasher tub assembly. The latch assembly includes a handle and a keeper slidably coupled with the handle. The handle is rotatable in a first direction, and the keeper is rotatable in a second direction opposite the first direction. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0007]    [0007]FIG. 1 is a perspective view of an under-the-counter type dishwasher with portions of the counter cut away.  
         [0008]    [0008]FIG. 2 is a partial cross-sectional view of the latch assembly shown in FIG. 1 in a closed position.  
         [0009]    [0009]FIG. 3 is a partial cross-sectional view of the latch assembly shown in FIG. 1 in an open position.  
         [0010]    [0010]FIG. 4 is a partial cross-sectional view, of an alternative embodiment, of a latch assembly that may be used with the dishwasher shown in FIG. 1. 
     
    
     DETAILED DESCRIPTION  
       [0011]    [0011]FIG. 1 is a perspective view of an under-the-counter type dishwasher  10  installed beneath a counter  12 . Dishwasher  10  includes a door  14  and a base  16 . Door  14  includes an upper edge  18  and a lower edge  20  which is hingedly coupled to base  16 . A control panel  22  including a plurality of controls  24  is secured to door  14 . Dishwasher  10  also includes a latch assembly  26 . In the exemplary embodiment, latch assembly  26  includes a handle  28 .  
         [0012]    In use, an operator depresses handle  28  to open door  14 . If dishwasher  10  is in operation, operation is interrupted, or is prevented, until door  14  is returned to a closed position. Door  14  can then be freely opened for loading or unloading dishes. To enable operations, an operator simply closes door  14  to re-engage latch assembly  26  such that door  14  is secured in a closed position.  
         [0013]    [0013]FIG. 2 is a partial cross-sectional view of latch assembly  26  (shown in FIG. 1) mounted to dishwasher door  14  (shown in FIG. 1). More specifically, FIG. 2 illustrates dishwasher door  14  and latch assembly  26  in a closed position. Dishwasher door  14  includes an outer wall  30  and an inner wall  32 . Dishwasher  10  (shown in FIG. 1) also includes a tub assembly  34  that includes a gasket  36 . Gasket  36  engages to inner wall  32  to form a seal between door  14  and tub assembly  34  when door  14  is secured in a closed position.  
         [0014]    In an exemplary embodiment, latch assembly  26  includes a keeper  38  attached to tub assembly  34 . In one embodiment, keeper  38  is formed integrally with tub assembly  34 . Keeper  38  includes a biasing member  40  and a head  42 . In one embodiment, biasing member  40  is formed unitarily with head  42 . Alternatively, biasing member  40  and head  42  are separate components. In an exemplary embodiment, biasing member  40  and head  42  are formed integrally. Head  42  includes a catch  44 , a switch actuator  46 , and a lock release projection  48 . In one embodiment, biasing member  40  and head  42  are formed from a metallic material. In another embodiment, biasing member  40  and head  42  are formed from a non-metallic material. Biasing member  40  has a thickness  50  that is measured between a top surface  52  and a bottom surface  54  of biasing member  40 . Thickness  50  is variably selected such that keeper  38  has a pre-determined flexibility to facilitate opening and closing door  14 .  
         [0015]    In the exemplary embodiment, latch assembly  26  also includes handle  28 , a handle retainer  56 , and a hinge pin  58 . In one embodiment, handle  28  includes a biasing member  60 , at least one pivot arm  62 , and a handle contact surface  64 . Pivot arm  62  is substantially circular and includes at least one opening therein for mating with hinge pin  58 . In one embodiment, handle retainer  56  is secured in a stationary position. In another embodiment, handle  28  is rotatably coupled to handle retainer  56  using hinge pin  58 . In a further embodiment, handle  28  is frictionally attached to handle retainer  56  without using hinge pin  58 . Handle  28  and hinge pin  58  are rotatably coupled such that handle  28  rotates in a first direction  66 . In one embodiment, handle  28  is formed unitarily with biasing member  60 , and biasing member  60  is slidably coupled with handle retainer  56 . Alternatively, handle  28  and biasing member  60  are separate components. In a further embodiment, handle  28 , handle retainer  56 , hinge pin  58 , biasing member  60 , pivot arm  62 , and contact surface  64  are fabricated from a plastic material. Alternatively, at least one of handle  28 , handle retainer  56 , hinge pin  58 , biasing member  60 , pivot arm  62 , and contact surface  64  is fabricated from a non-plastic material.  
         [0016]    In use, handle  28  and keeper  38 , are in a first position such that a switch  70  is in a closed state, keeper  38  is securing door  14  to tub assembly  34 , and dishwasher operations are enabled. When handle  28  rotates in first direction  66 , contact surface  64  makes sliding contact with lock release projection  48 . Such contact causes keeper  38  to rotate in a second direction  68  that is opposite from first direction  66 , and dishwasher operations are interrupted.  
         [0017]    [0017]FIG. 3 is a partial cross-sectional view, of latch assembly  26  (shown in FIG. 1) mounted to dishwasher door  14  (shown in FIG. 1). More specifically, FIG. 3 illustrates door  14  and latch assembly  26  in an open position.  
         [0018]    In use, handle  28  and keeper  38 , are in a first position such that switch  70  is in a closed state, keeper  38  is securing door  14  to tub assembly  34 , and dishwasher operations are enabled. When handle  28  rotates in first direction  66 , contact surface  64  makes slidable contact with lock release projection  48 . Such slidable contact causes keeper  38  to rotate in a second direction  68  that is opposite from first direction  66 . Keeper  38  then unsecures door  14  from tub assembly  34 , switch  70  transitions from a closed state to an open state, and dishwasher operations are interrupted.  
         [0019]    During assembly, latch assembly  26  is attached to dishwasher  10  and secures dishwasher door  14  to dishwasher tub assembly  34 . Handle retainer  56  includes at least one substantially circular projection that frictionally connects handle  28  to handle retainer  56 . Keeper  38  is attached to dishwasher tub assembly  34  such that keeper  38  is slidably coupled to handle  28 .  
         [0020]    [0020]FIG. 4 is a partial cross-sectional view of an alternative embodiment of a latch assembly  110  that may be used with a dishwasher (not shown) such as dishwasher  10  shown in FIG. 1. Door  112  includes an upper edge  114  and a lower edge (not shown) which is hingedly coupled to a base (not shown). Dishwasher door  112  also includes an outer wall  118  and an inner wall  120 . The dishwasher includes a tub assembly  122  including a gasket  124 . Gasket  124  engages inner wall  120  to form a seal between door  12  and tub assembly  122  when door  112  is secured in a closed position.  
         [0021]    In an exemplary embodiment, latch assembly  110  includes a keeper  126  attached to tub assembly  122 . In one embodiment, keeper  126  is formed integrally with tub assembly  122 . Keeper  126  includes a biasing member  128  and a head  130 . In one embodiment, biasing member  128  is formed unitarily with head  130 . In an exemplary embodiment, biasing member  128  is formed integrally with head  130 . Alternatively, biasing member  128  and head  130  are separate components. Head  130  includes a catch  132 , a switch actuator  134 , and a lock release projection  136 . In one embodiment, biasing member  128  and head  130  are formed from a metallic material. In another embodiment, biasing member  128  and head  130  are formed from a non-metallic material. Biasing member  128  also has a thickness  138  measured between a top surface  140  and a bottom surface  142  of biasing member  128 . Thickness  138  is variably selected such that keeper  126  has a pre-determined flexibility to facilitate opening and closing door  112 .  
         [0022]    In the exemplary embodiment, latch assembly  110  also includes a handle  144 , and a handle retainer  146 . In one embodiment, handle  144  includes at least one pivot arm  148 , and a contact surface  150 . Pivot arm  148  is substantially circular and includes at least one opening therein for mating with handle retainer  146 . In one embodiment, handle retainer  146  frictionally retains handle  144 . In an alternative embodiment, handle  144  is pivotally attached to handle retainer  146  with a hinge pin (not shown). Handle retainer  146  and handle  144  are rotatably coupled such that handle  144  rotates in a first direction  152 . In one embodiment, contact surface  150  includes a substantially planar surface and lock release projection  136  includes a substantially planar surface, such that contact surface  150  planar surface and lock release projection  136  planar surface are in slidable contact. In one embodiment, handle  144 , handle retainer  146 , pivot arm  148 , and contact surface  150  are formed from a plastic material. In an alternative embodiment, at least one of handle  144 , handle retainer  146 , pivot arm  148 , and contact surface  150  is formed from a non-plastic material.  
         [0023]    In use, handle  144  and keeper  126 , are in a first position such that a switch  154  is in a closed state, keeper  126  is securing door  112  to tub assembly  122 , and dishwasher operations are enabled. When handle  144  rotates in first direction  152 , contact surface  150  makes sliding contact with lock release projection  136 . Such contact causes keeper  126  to rotate in a second direction  156  that is opposite from first direction  152 . Keeper  126  unsecures door  112  from tub assembly  122 , switch  154  transitions from a closed state to an open state, and dishwasher operations are interrupted.  
         [0024]    The above described latch assembly includes a keeper, a handle retainer, and a handle attached to the handle retainer such that the handle slidably couples with the keeper to open or close the door. The latch assembly uses fewer components than other known latch assemblies, and is thus less complex than other known latch assemblies. As a result, assembly of the latch assembly is facilitated to be more cost effective and less time consuming.  
         [0025]    While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.