Abstract:
A water switch of a water-bearing appliance, in particular a domestic appliance, including at least one water supply path, several water discharge paths and an adjustable water distribution element, the water distribution element having at least one passage opening and being rotatable around an axis from a first angular position to a second angular position, in the first angular position the at least one passage opening connecting the at least one water supply path to a first water discharge path, and in the second angular position the at least one passage opening connecting the at least one water supply path to a second water discharge path, is characterized in that a guiding mechanism is provided for guiding an axial movement along the axis of the water distribution element when the water distribution element rotates from the first angular position to the second angular position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 USC 119 to European Patent Application No. 11004954 filed on Jun. 17, 2011 and U.S. Provisional Patent Appl. No. 61/501,991 filed on Jun. 28, 2011, the entire disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to a water switch of a water-bearing appliance, in particular a domestic appliance, including at least one water supply path, several water discharge paths and an adjustable water distribution element, the water distribution element having at least one passage opening and being rotatable around an axis from a first angular position to a second angular position, in the first angular position the at least one passage opening connecting the at least one water supply path to a first water discharge path, and in the second angular position the at least one passage opening connecting the at least one water supply path to a second water discharge path. 
         [0004]    2. Description of the Related Art 
         [0005]    Water switches, also called fluid switches or water diverters, are used in water-bearing appliances, in particular domestic water-bearing appliances, such as washing machines or dishwashers, to control flows of liquid in the water-bearing appliance. When used in washing machines water switches serve to dispense washing or rinsing water for example to a first or second detergent compartment of two detergent compartments. When used in dishwashers water switches serve to dispense washing water, also referred to as washing liquor, for example alternately to a spray arm for an upper rack or to a spray arm for a lower rack of the respective dishwasher or simultaneously to both spray arms. 
         [0006]    From DE-A-1610146 a water switch is known to include a rotatable control slider which is provided in a cylindrical housing, connecting a supply channel to one of a number of discharge channels by means of a swivel tube. The swivel tube has a rotating pin disposed in a socket of the supply channel in the likeness of a ball and socket joint. A sealing element in the likeness of a hollow cylinder is secured to the mouth of the swivel tube opposite the discharge channels and slides in a cylindrical guide running concentrically to the outer surface of the housing. 
         [0007]    Another water switch known from DE-A-10133130 includes a rotating slider disposed in a pressure chamber of a circulating pump before branching pressure connections. The water switch blocks and releases the pressure connections for washing liquid. A gear drive for the rotating slider is arranged outside and inside the pressure chamber. The rotating slider in question is formed by a cylindrical component, in the cylindrical wall of which one or more apertures are located between one and a number of movable closing elements with a valve function. The apertures and the closing elements are configured in their relative position to the pressure connections, which form the water supply and/or water discharge connections, such that depending on the rotation of the rotating slider, the pressure connections opposite its cylinder wall are released or blocked in a sealing manner. 
         [0008]    Accordingly, a need exists for a water switch of a water-bearing appliance, for blocking or releasing at least one water supply path to one of several water discharge paths, the water switch being cost efficient in production, being easy to switch, and providing an effective water flow control for the water-bearing appliance associated therewith. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with one aspect of the invention a water switch of a water-bearing appliance, in particular a domestic appliance, is provided, the water switch including at least one water supply path, several water discharge paths and an adjustable water distribution element, the water distribution element having at least one passage opening and being rotatable around an axis from a first angular position to a second angular position, in the first angular position the at least one passage opening connecting the at least one water supply path to a first water discharge path, and in the second angular position the at least one passage opening connecting the at least one water supply path to a second water discharge path. Further, a guiding mechanism is provided for guiding an axial movement along the axis of the water distribution element when the water distribution element rotates from the first angular position to the second angular position. The axial movement of the water distribution element, in particular, takes place while the water switch is unpressurized. In order to prevent the water distribution element from moving back after its rotation from one angular position to the next angular position, in particular, a reverse-look is provided. The water distribution element may serve to connect one or several water supply paths to one or several different water discharge paths and/or to interconnect several water discharge paths. 
         [0010]    Preferably the guiding mechanism includes at least one cylindrical portion being guided in a respective tubular portion surrounding the at least one cylindrical portion, and/or wherein further, in particular, the at least one cylindrical portion is connected to an armature of an associated magnetic coil. 
         [0011]    In a preferred embodiment, the water distribution element is disk shaped and extends perpendicular to the axis, and/or wherein further, in particular, the cylindrical portion and/or the armature extend along the axis. 
         [0012]    In another preferred embodiment, the guiding mechanism includes at least one first ramp portion sliding along a respective second ramp portion during the axial movement of the water distribution element, the pair of a first ramp portion and a respective second ramp portion thereby generating a torque for rotating the water distribution element from the first angular position in the direction to the second angular position. 
         [0013]    Further preferred, several pairs of a first ramp portion and a respective second ramp portion, in particular, 8 pairs of a first ramp portion and a respective second ramp portion, are circumferentially distributed, and in particular, evenly circumferentially distributed, around a cylindrical portion of the guiding mechanism. 
         [0014]    In a further preferred embodiment, the number of pairs of a first ramp portion and a respective second ramp portion equals the number of water discharge paths. 
         [0015]    In accordance with a preferred aspect of the invention the number of pairs of a first ramp portion and a respective second ramp portion is larger than the number of water discharge paths, whereby at least at one angular position of the water distribution element the respective water discharge is closed. 
         [0016]    In accordance with yet another preferred aspect of the invention at least one first pair of a first ramp portion and a respective second ramp portion and at least one second pair of a first ramp portion and a respective second ramp portion are located on two opposite faces of the water distribution element. Each of the two pairs of a first ramp portion and a respective second ramp portion generates a part of the necessary torque for moving the water distribution element along its travel from the first angular position to the second angular position. 
         [0017]    In accordance with still another preferred aspect of the invention the at least one first pair of a first ramp portion and a respective second ramp portion at one face of the water distribution element generates about one half of the rotary movement of the water distributing element, and the at least one second pair of a first ramp portion and a respective second ramp portion at the opposite face of the water distribution element generates about the second half of the rotary movement of the water distributing element. 
         [0018]    Finally, in a further preferred embodiment of the solution according to the invention, the guiding mechanism includes a spring, in particular a helical spring, biasing the water distribution element in the direction of the several water discharge paths, and/or wherein further, in particular, the spring surrounds a cylindrical portion of the guiding mechanism. 
         [0019]    The water switch apparatus according to the invention can be switched with very low expenditure of energy, because the water distribution element associated therewith does not only rotate from a first angular position to at least one second angular position but also does an axial movement during this rotational movement. With this axial movement the water distribution element can be lifted off a sealing element located at the passage opening of the water distribution element. 
         [0020]    The sealing element helps providing a water tight passageway through the water switch. Further, the sealing element is suitable for sealing a water passage opening which extends through a flat rotating disk in respect to water discharge lines opposite said flat rotating disk. This water switch according to the invention is even suitable for sealing openings provided in a cylinder wall. 
         [0021]    According to another advantage with this solution, the water switch does not produce an unwanted high pressure loss in the water flow to be distributed in each instance due to only very low deflection within the water distribution element and the flow paths connected therewith. 
         [0022]    Finally, on one hand, the water switch provides the possibility to connect a very large number of water discharge paths. On the other hand, a water tight seal is easily provided against all of the water discharge paths not being connected to the water supply path. 
         [0023]    Hereinafter an embodiment of the solution according to the invention is described referring to the schematic drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]      FIG. 1  is a perspective explosion view of an embodiment of a water switch according to the invention. 
           [0025]      FIG. 2  is a perspective view of the water switch of  FIG. 1 . 
           [0026]      FIG. 3  is the sectional view indicated in  FIG. 2  showing a position of the respective water distribution member during distributing water to a water discharge path. 
           [0027]      FIG. 4  is the sectional view indicated in Fig. showing a position of the respective water distribution element during the movement of switching from one water discharge path to another water discharge path. 
           [0028]      FIG. 5  is the sectional view indicated in  FIG. 6 . 
           [0029]      FIG. 6  is a top view of the respective lower housing portion of the water switch of  FIG. 1 . 
           [0030]      FIG. 7  is a perspective top view of the lower housing portion as shown in  FIGS. 5 and 6 . 
           [0031]      FIG. 8  is the sectional view indicated in  FIG. 9 . 
           [0032]      FIG. 9  is a top view of the respective upper housing portion of the water switch of  FIG. 1 . 
           [0033]      FIG. 10  is a perspective bottom view of the upper housing portion as shown in  FIGS. 8 and 9 . 
           [0034]      FIG. 11  is a first perspective view of the respective water distribution element of the water switch of  FIG. 1 . 
           [0035]      FIG. 12  is a second respective view of the water distribution element as shown in  FIG. 11 . 
           [0036]      FIG. 13  is the sectional view indicated in  FIG. 14 . 
           [0037]      FIG. 14  is a top view of the water distribution element as shown in  FIG. 11 to 13 . 
           [0038]      FIG. 15  is a bottom view of the water distribution element as shown in  FIG. 11 to 14 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0039]    A water switch  10  for a water-bearing appliance, in particular a domestic appliance, includes the main structural members of a magnetic coil  12 , an upper housing portion  14 , a spring  16 , a water distribution element  18  and a lower housing portion  20 . The magnetic coil  12  is fitted on top of the upper housing portion  14 , while the spring  16  and the water distribution element  18  are mounted in the hollow space provided by the upper housing portion  14  and the lower housing portion  20 . The spring  16  is formed as a helical spring, is located between the upper housing portion  14  and the water distribution element  18  and thereby biases the water distribution element  18  against the lower housing portion  20 . 
         [0040]    The magnetic coil  12  has a first connector pin  22  and a second connector pin  24  both protruding in a lateral direction at the upper rim of the magnetic coil  12 . The first and second connector pins  22  and  24  are for connecting an electrical plug (not shown) and for supplying current to the magnetic coil  12 . The current supplied flows through a wire-wound coil (not shown) which is located within a cylindrical hollow body  26  of the magnetic coil  12 . The magnetic coil  12  is a standardized structural element which is produced in large scale manufacture. Thus, the magnetic coil  12  can be produced very cost-effective. 
         [0041]    The upper housing portion  14 , which is shown in detail in  FIG. 8 to 10 , is made of plastic or another synthetic material by an injection molding process. It has the shape of a round, in particular circular disc from which a water supply path  28  in the form of a supply connection tube is projecting radially at the outer range thereof. The water supply path  28  leads to an approximately circular channel  30  which is located at the inner side of this disc-shaped housing shell of the upper housing portion  14 . At the center of this disc shape a cylindrical housing portion  32  protrudes to the outside along a central axis of the disc (not figured). The cylindrical housing portion  32  forms a tubular portion for pinning up the cylindrical hollow body  26  thereon and for accommodating a portion of the water distribution element  18  therein, as will be explained in further detail hereinafter. 
         [0042]    Parallel with the cylindrical housing portion  32  a snap-in pin  34  protrudes from the disk. The snap-in pin  34  is adapted to embrace the cylindrical hollow body  26  in order to hold the magnetic coil  12  on the cylindrical housing portion  32 . 
         [0043]    Two notches  36  project radially at one of two diametrical positions of the outer range of the disk-shape housing shell. These notches  36  are provided for a water-tight connection of the lower housing portion  20  to the upper housing portion  14  as it is shown in  FIG. 2 . 
         [0044]    Eight first ramp portions  38  and adjacent first recess portions  40  are surrounding the cylindrical housing portion  32  at the inner center of the housing shell of the upper housing portion  14 . Each ramp portion  40  is made of a ramp surface  42  which is skewed relative to said axis. The ramp surface  42  is positioned in an angel relative to the axis of about 40 degrees to 60 degrees, preferably 50 degrees. The ramp surface  42  terminates at a ramp edge  44 , which is formed by a smaller and steeper counter ramp  46 . The ramp edge  44  is rather dull. The first recess portions  40  are limited by parallel sidewalls forming a type of slot into which a second ramp portion facing the first ramp portion can be inserted, as will be explained later. 
         [0045]    The water distribution element  18  is shown in detail in  FIG. 11 to 15 . It is made of plastic or synthetic materials, too. The water distribution element  18  is formed like a circular disc, which has eight water distribution positions  48  on its disk-face. The water distribution positions  48  are located with equal distances along a circle on the face. One of the water distribution positions  48  is open, including a passage opening  50  which permeates the disk. The seven remaining water distribution positions  48  are closed. 
         [0046]    At each water distribution position  48  a sealing ring  52  is provided at the lower side of the disk of the water distribution element  18 . One of these sealing rings  52  is located at a margin  54  of the passage opening  50 . The other sealing rings  52  are fixed to the disk by means of pins  56  protruding through respective openings in the disk. 
         [0047]    A first cylindrical portion  58  protrudes at the central area of the disk-shape and carries a rod-shaped armature  60  made from iron or ferro-magnetic material. The armature  60  elongates the first cylindrical portion  58  along the axis. When mounting the water distribution element  18  into the upper housing portion  14 , the armature  60  dives into the cylindrical housing portion  32  and into the cylindrical hollow body  26  of the magnetic coil  12 . 
         [0048]    Eight second ramp portions  62  and adjacent recess portions  64  are surrounding the first cylindrical portion  58 . These second ramp portions  62  are also formed by ramp surfaces sloping relative to the axis with an angel of between 40 degrees and 60 degrees, preferably of 50 degrees, a respective ramp edge and an associated smaller counter ramp. The ramp surfaces of the second ramp portions  62  are positioned in a manner for sliding along the ramp surfaces  42  of the first ramp portions  38  when the water distribution element  18  moves in an axial direction, and further for diving into the respective first recess portions  40  after the ramp surfaces have left the phase of sliding contact. 
         [0049]    Around these second ramp portions  62  eight through holes  66  are located in the disk of the water distribution element  18  serving as hydraulic flow compensation during movement of the water distribution element  18  in axial direction. 
         [0050]    Two latches  68  are located in a tangential manner at two diametrical positions of an outer margin  70  of the disk-shape of the water distribution element  18 . These latches  68  help to ensure that the water distribution element  18  can only rotate on one direction. 
         [0051]    On the lower face of the disk-shape of the water distribution element  18  a guiding pin  72  projects axially and forms a second cylindrical portion. The guiding pin  72  has longitudinal slots  74  on this lateral surface which also leads into the first cylindrical portion  58  and into the armature  60  providing further water compensation. 
         [0052]    The second cylindrical portion formed by the guiding pin  72  is surrounded by eight first ramp portions  76  and adjacent first recess portions  78 . These ramp portions  76  and recess portions  78  correspond to those first ramp portions  38  and first recess portions  40  mentioned above, but they are offset in the circumferential direction by nearly the angular width of the first ramp portions  38 . 
         [0053]    The cupular lower housing portion  20  is depicted in further detail in  FIG. 5 to 7 . It is also made of plastic or another synthetic material by injection molding and includes a sealing edge or sealing ring  80  at its upper circular edge. Two notch catchers  82 , each for clamping one of the notches  36 , project radially at two diametrical positions of the outer sidewall of the lower housing portion  20 . 
         [0054]    The bottom of the lower housing portion  20  provides eight water discharge positions  84  located with equal distances along a circle on the inner face of the bottom. One position  86  of these water discharge positions  84  is closed; the remaining seven positions are open. They have respective water discharge paths  88  in the form of a discharge connection tube connected therewith. 
         [0055]    Further, at the inner surface of the sidewall of the cup-shaped or cupular lower housing portion  20  sixteen latch ramps  90  are formed. These latch ramps  90  are designed so that the latches  68  of the water distribution element  18  can slide along. 
         [0056]    A guiding cylinder  92  accommodates the guiding pin  72  and projects in the center of the bottom to the outside of the lower housing portion  20 . At the center of the inside of the bottom eight second ramp portions  94  and adjacent second recess portions  96  surround the opening leading into the guiding cylinder  92 . 
         [0057]    During operation of the water switch  10 , the magnetic coil  12  pulls the armature  60  and the water distribution element  18  connected therewith in the direction of the upper housing portion  14  and biases the spring  16 . While moving axially, the first ramp portions  38  and the second ramp portions  62  contact each other and start to work as a guiding mechanism by sliding along each other. The sliding process provides a torque which starts to rotate the water distribution element  18  from its starting first angular position to the direction of a next second angular position. These positions are those of the water distribution positions  48  mentioned above. The sliding of the ramp portions  38  and second ramp portions  62  provide half of the travel from the first angular position to the second angular position. 
         [0058]    The second half of the travel is provided, when the magnetic coil  12  stops pulling the armature  60  and the spring  16  pushes the water distribution element  18  back along the axis in its previous axial position. While moving back axially, the first ramp potions  76  now come into contact with the second ramp portions  94  in order to slide along each other and in order to turn the water distribution element  18  further along the second half of the travel. 
         [0059]    At the end of the travel, the sealing rings  52  come into contact with respective water discharge paths  88  again. While seven of the discharge paths are closed by means of the water distribution element  18  in this manner, one path through the passage opening  50  is open.