Patent Publication Number: US-2020281355-A1

Title: Household appliance comprising a liquid tank

Description:
The present invention relates to a household appliance comprising a liquid tank, wherein the tank is adapted for translational movement between a use position in which the tank is positioned within a housing of the household appliance and a servicing position in which the tank is at least partially extracted from the housing, the household appliance further comprising biasing means for biasing the tank towards the servicing position, and releasable latch means for selectively arresting the tank in the use position or releasing the tank for movement towards the servicing position. 
     The present invention is of particular advantage for household appliances that are equipped with liquid tanks that require frequent servicing, such as condensation dryers that collect water in a water tank, or food preparation ovens that provide a steaming function by which water or steam is fed into the cooking cavity during a cooking process. Whereas in a condensation dryer the tank is to be emptied preferably after each drying cycle, but at the latest when the tank is filled, in an oven having a steam generator, such as a boiler arrangement that is located outside the cooking cavity, or a pan that is located inside the cooking cavity in which water is heated and thus evaporated, the tank which feeds the steam generator always should be freshly filled when starting a cooking cycle, and further remaining water should be emptied from the tank after conclusion of a cooking cycle. 
     While in such household appliances the tank needs to be serviced frequently, so as to be filled, emptied or cleaned, the tank should be easily accessible, which however is difficult to implement given the design constraints in modern household appliances. Thus there are household appliances on the market, in which the tank is hidden behind the front panel, which solution necessitates that the front panel needs to be removed or displaced so as to allow access to the tank, which not only requires a complicated and thus costly mechanics, but which also is disadvantageous in terms of handling. 
     In order to overcome these disadvantages, it was suggested in EP 2 522 915 A1 to provide for a household appliance in which the tank is located such that in the use position of the tank a front panel thereof is arranged flush with the front panel of the household appliance, which thus allows providing for a tank that is directly accessible, but nevertheless can be integrated into the front panel. Since in such a flush design the provision of handles or the like for manipulating the tank are to be avoided, in the household appliance suggested in EP 2 522 915 A1 the tank is provided with a retractable pulling element which carries a front panel that in the use position of the tank is located flush with the front panel of the household appliance, but which, similarly as a retractable ballpoint pen, can be brought into a position in which the front panel of the pulling element is located offset to the front panel of the household appliance and thus allows gripping of the tank, so that the tank can be pulled out for a distance to expose a filling opening of the tank. 
     Also in EP 2 550 902 A1 there is disclosed a household appliance in which the tank is located such that in the use position of the tank a front panel of the tank is arranged flush with the front panel of the household appliance. In order to move the tank into an extracted position so as to expose a filling opening, the user has to push onto a front section of the tank which is exposed within the front panel of the household appliance. By pushing the tank for a certain distance inwards, a mechanism is released which holds the tank inside the household appliance, so that the tank can be exerted by a spring mechanism. 
     Common to the household appliances disclosed in EP 2 522 915 A1 and EP 2 550 902 A1 is that both require complicate mechanics for displacing the tank into a servicing position in which fresh water can be filled into the tank. 
     It is an object of the present invention to provide for a household appliance with a liquid tank, in which the tank is adapted for translational movement between a use position in which the tank is positioned within a housing of the household appliance and a servicing position in which the tank is at least partially extracted from the housing, wherein complicate mechanics as they are required in the above prior art documents are not required to provide for a translational movement of the tank from a use position to a servicing position. 
     In a household appliance comprising a liquid tank, wherein the tank is adapted for translational movement between a use position in which the tank is positioned within a housing of the household appliance and a servicing position in which the tank is at least partially extracted from the housing, the household appliance further comprising biasing means for biasing the tank towards the servicing position, and releasable latch means for selectively arresting the tank in the use position or releasing the tank for movement towards the servicing position, the above object is solved in that the household appliance further comprises a carriage associated to the tank and configured for translational movement along guide means provided in the housing, wherein the biasing means comprises a spring element configured to be loaded when the tank is moved from the servicing position towards the use position, and wherein the latch means comprises a catch provided at the carriage, a locking member located at the housing which in the use position of the tank engages the catch to arrest the tank in the use position, and release means for disengaging the locking member from the catch. 
     The household appliance of the present invention, which particularly may be a cooking oven, a steamer or a condensation dryer, comprises a carriage which provides for translational movement of the tank, such as a linear movement in a direction generally perpendicular to the front of the household appliance. The carriage is configured to load a spring when the tank is moved from the servicing position towards the use position in which the carriage and hence the tank is locked, wherein the spring acts as biasing means for the carriage, i.e. acts as an expulsion means for the tank which pushes the carriage and hence the tank outwards towards the servicing position when the lock is released by activating a release means for disengaging the locking member from the catch. 
     The present invention thus provides a household appliance in which the tank can be designed flush with the front panel of the household appliance and without means for manipulating the tank, such as a handle or a gripping orifice, so that the tank can be easily integrated into the design of the front panel, wherein there is provided in a simple and thus cost effective manner for means for ejecting the tank on request of the user. The locking member may comprise a retractable piston or a rotatable hook which in the use position of the tank engages a catch provided at the carriage. Preferably, the locking member is biased towards engagement with the catch, so that the locking member snaps into engagement with the catch upon the tank reaching its use position. 
     In preferred embodiments, the catch comprises a ramp surface configured to displace the locking member when the tank is moved towards the use position and to release the locking member to engage the catch upon the tank reaching the use position. In such embodiments, the combination of catch and locking member provides for mutual locking, and releasing, respectively, wherein when shifting the tank inwardly into its use position, the locking member moves along the ramp surface of the catch, during which ramping movement the locking member is increasingly biased, wherein upon reaching the end of the ramp surface the locking member snaps back and thus locks the catch, in which position the tank is held against a biasing force in its use position. When the user wishes to displace the tank into its servicing position, the release means is activated so as to disengage the locking member from the catch in which manner the tank is released against its biasing force and thus is ejected for a certain distance, such as to expose a fill opening of the tank. 
     Preferably the household appliance comprises an electric drive for retracting the locking member out of its engagement with the catch, which allows releasing the tank to move towards its servicing position by activating a respective switching element. Alternatively or additionally, the electric drive also could be activated by the control of the household appliance, so as to automatically eject the tank in the course of an operating program, such as in a dryer at the end of a drying operation. 
     In order to provide for ejection of the tank on request of the user, the household appliance further may comprise an actuation element for activating the electric drive, wherein the actuation element is positioned at a front panel of the household appliance or at a front panel of the liquid tank. The actuation element can be a switch, such as a touch sensitive element, that can be positioned at the tank or in proximity thereto. 
     In order to allow filling the tank by only a partial ejection of the tank, the tank advantageously comprises a fill opening in the upper side of the tank at the front end of the tank. In such embodiments, the servicing position, or a first servicing position, can be a position in which the tank is extracted to an extent such that the fill opening is exposed. A further servicing position can be a position, in which the tank is fully extracted from the household appliance, such that the tank can be carried to a tap for filling, or to a sink for emptying the tank. 
     The carriage can be fixedly connected to the tank or can be formed integrally with the tank, so that the tank and the carriage form a unitary component. 
     In the alternative, the tank can be removably connected to the carriage, such as in embodiments which shall allow a full extraction of the tank from the household appliance, so as to allow taking the tank to a tap or to a sink. 
     Whereas in such latter embodiments the releasable connection between the tank and the carriage can be implemented in any feasible manner, such as by providing for recesses or hooks at the tank (or the carriage) for accommodating corresponding pins that are provided at the carriage (or the tank, respectively), wherein for releasing the tank from the carriage the tank is to be lifted to disengage the pins from the grooves or hooks, in preferred embodiments the sliding means for accommodating the tank are oriented generally parallel to the guide means. For example, when the guide means for the carriage is configured for providing for a linear movement of the carriage relative to the housing, wherein for example a ball bearing slide may be provided as the guide means, the sliding means for accommodating the tank advantageously may comprise straight guide rails for guiding sliders of the tank. While when displacing the tank to its use position, the tank is withdrawn from the household appliance like a drawer, the tank can be removed from the household appliance, such as to fill the tank at a tap, by simply continuing such opening movement, i.e. by pulling at the tank in the direction of the opening movement by which the tank is released from the carriage. 
     In preferred embodiments, the household appliance further comprises a fluid coupling that provides for connection of the tank to a fluid line of the household appliance, such as in embodiments in which the household appliance is a steam oven, a fluid line that connects to a steam generator, or in embodiments in which the household appliance is a condensation dryer, a fluid line that connects to a condenser. 
     In order to provide for a quick-connection of the tank during insertion into or removal from the household appliance, the household appliance can be provided with a fluid coupling that comprises a first member which is provided at the tank and a second member that is provided either at the carriage or at the housing and which is connected to a fluid line of the household appliance. That is, the fluid coupling can be designed to provide for a fluid connection to the tank when the tank is inserted into the carriage, in which case the second coupling member is provided at the carriage and is connected via a flexible hose to the fluid line of the household appliance. In the alternative, the second coupling member can be provided at the housing, i.e. is fixedly arranged in the housing of the household appliance, wherein the coupling to the tank is effected by setting the tank into the carriage and then moving the carriage and hence the tank towards the use position of the tank, in the course of which movement the fluid coupling is effected. 
     The household appliance further may comprise dampening means for slowing the movement of the carriage before the tank reaches the servicing position, so as to provide for a smooth stop of the tank when it reaches its servicing position. 
    
    
     
       Preferred embodiments of the present invention are described below by reference to the drawings in which: 
         FIG. 1  is a perspective view of a household appliance in accordance with the present invention. 
         FIG. 2  is a view similar to  FIG. 1  with the tank fully extracted; 
         FIG. 3  is a sectional view of the household appliance shown in  FIGS. 1 and 2  with the tank in the use position; 
         FIG. 4  is a sectional view similar to  FIG. 3  with the tank in a servicing position for filling the tank; 
         FIG. 5  is a sectional view similar to  FIGS. 3 and 4  during full extraction of the tank; and 
         FIG. 6  is a sectional view similar to  FIG. 3  which illustrates an alternative embodiment. 
     
    
    
     In the exemplary embodiment illustrated in  FIG. 1 , the household appliance is an electric cooking oven that provides for a steaming function. Oven  10  comprises a cooking chamber into which steam can be applied from the steam generator which is fed with water from a water tank  12 . In the embodiment shown in  FIG. 1 , water tank  12  is a generally box shaped container which in its use position is arranged in an upper section of the oven above the cooking chamber. Water tank  12  can be a molded plastic component which is designed for insertion into a respective receptacle  14  by an aperture  16  which is provided in the front panel  18  of the oven. At its front face, tank  12  is provided with a cover element  20 , the shape of which corresponds to the shape of aperture  16 . While in the embodiment illustrated in  FIG. 1  the water tank  12  has the shape of a generally rectangular block having at least for a portion of its length a square cross-section, which water tank has a volume of about 1 liter, the tank of course can have any other size or cross-sectional shape, such as a circular or rectangular cross-sectional shape. Furthermore, the cover element  20  may have a shape that is different from the cross-sectional shape of the tank  12 , so as to adapt the design of cover element  20  to the design of front panel  18 . Thus, the tank  12  for example may have a circular cross-sectional shape, but the cover element  20  may have a square shape. 
     Whereas in many cases it will be preferred that cover element  20  has a similar surface design as front panel  18 , such as by producing cover element  20  and front panel  18  from the same material or by providing both these components with a same coating, cover element  20  also may have a design that differs from that of front panel  18  so as to provide for a signaling function of cover element  20 . 
     Towards its front end tank  12  comprises a fill opening  22  via which water can be filled into the tank. While  FIG. 1  shows tank  12  in an intermediate position as it will be attained during removal of the tank, it is to be understood that in order to enable filling of the tank, it is sufficient to eject the tank from the receptacle  14  only by a short distance which corresponds to the dimension of the fill opening  22  measured in the longitudinal direction of the tank, as will be explained in more detail by reference to  FIG. 4 . 
       FIGS. 3 to 5  depict horizontal sectional views of the tank section of the household appliance shown in  FIGS. 1 and 2 . In particular,  FIG. 3  shows the tank  12  when in its use position, i.e. when fully inserted into a corresponding receptacle  14  provided within a housing  15  of oven  10 . In the use position the front face of the tank which as shown in  FIG. 1  may be formed by a cover element  20  is positioned flush with the front panel  18 , so that the tank can be fully integrated into the front panel  18  so as to provide for a continuous and consistent design of the front panel. At its rearward portion, tank  12  is accommodated by a carriage  24 . Carriage  24  is configured to be movable parallel to the longitudinal direction of tank  12  as shown in  FIG. 3  by arrow  26 . To this end, there are provided guide rails  28  which support carriage  24  for movement between a first end position corresponding to the use position of the tank shown in  FIG. 3 , and a second end position shown in  FIG. 4  in which the carriage  24  has been displaced outwardly so as to eject the tank by a length such that the fill opening  22  is fully accessible to allow filling of the tank. Whereas in the somewhat schematic views of  FIGS. 3 to 6  the carriage  24  is shown to extend so as to accommodate the rear portion of tank  12  it should be understood that in the preferred embodiments the carriage  24  is longer and thus, when in the position shown in  FIG. 4 , may extend to close to the rear side of front panel  18 , which not only provides for a more stable support of the tank but which also facilitates inserting the tank into the carriage after the tank having been completely removed. 
     Carriage  24  is biased towards the second end position of  FIG. 4  by means of a compression spring  30 , which is positioned to extend between an attachment  32  at carriage  24  and a seat  34  of housing  15 . In the use position of tank  12  in which spring  30  is in a compressed state, the carriage is held by means of a catch  36  provided at the carriage, which is engaged by a locking member  38 , which in the embodiment depicted in  FIGS. 3 to 5  is biased towards the locking position by means of a spring biased piston  40 . In particular, as illustrated in  FIGS. 3 to 5 , catch  36  comprises a ramp surface  42 , which when pushing the tank  12  and hence the carriage  24  inwardly so as to move the tank into its use position, displaces the locking member  38  against the biasing force of a biasing spring  44 . When catch  36  passes the locking member  38  upon the tank reaching its use position, the locking member  38  is released and thus snaps back into the locking position shown in  FIG. 3 . When tank  12  is to be ejected from receptacle  14 , such as to fill or empty the tank, the engagement between catch  36  and locking member  38  is released by activating a release means, which in preferred embodiments is an electrically driven actuator. In the embodiment shown in  FIGS. 3 to 5  the release means comprises a solenoid actuator  46  which is configured to retract piston  40  and hence locking member  38  against the biasing force of biasing spring  44 , so that the carriage  24  is pushed outwards by the force of compression  30  and thus the tank  12  is ejected into the servicing position illustrated in  FIG. 4 . Solenoid actuator  46  may be activated by applying an electrical signal, either user activated such as by pushing a respective switch, or automatically under the control of a controller  47  of the household appliance in the course of executing a control program. The switch for activating actuator  46  may be a switch  48  provided at the front panel  18  (see  FIG. 1 ), a switch  50  that is provided in the cover element  20  of tank  12  (see  FIG. 3 ), or may be a switch  52  which is provided at the front face of tank  12  and which can be activated by depressing a button element  54  which in the embodiment illustrated in  FIG. 2  replaces cover element  20 . In such latter embodiment the tank preferably comprises a wire harness  55  that is embedded in a wall of the tank  12  and which connects the switch  52  with contacts  56  provided at the rear wall of the tank. As illustrated in  FIG. 3 , in the use position of the tank, contacts  56  electrically engage contacts  57  provided at the rear wall of the carriage  24 , which are connected by wires  59  to controller  47 . 
     Whereas in such embodiment the contacts  56  and  57  serve for connecting activation switch  50  to controller  47 , contacts  56  and  57  also can be used as means for detecting whether the tank  12  is properly inserted into carriage  24 . That is, contacts  56  and  57  also may be provided in embodiments in which an activation switch is located not at the tank but at the front panel, such as switch  48  shown in  FIG. 1 , in which case the contacts  56  that are provided at the tank can be connected to each other and a determination can be made whether the tank is properly inserted by checking whether a signal applied to one of contacts  56  and  57  also is present at the respective other one of the two contacts. 
     Instead of a release means that can be activated electrically, there also can be provided a manually releasable locking member. For example, as is illustrated in  FIG. 6 , there can be provided a rotatable latch  58  having a first leg  61 , which is biased into engagement with the catch  36  by a biasing spring  60  and which can be released from its engagement with the catch  36  by means of a push rod  62 . To this end push rod  62  is arranged to extend between a push button  64  and a second leg  66  of the rotatable latch  58 . By pressing push button  64  which in the locking position of the first leg  61  projects from front panel  18  (see also  FIG. 1 ), the rotatable latch  58  is rotated against the biasing force of spring  60 , so as to release catch  36  and hence eject carriage  24  with tank  12 . 
     In order to establish a connection to a fluid line when the tank is inserted into the carriage, there is provided for a fluid coupling which comprises a first member  68  provided at the rear end of the tank  12  which cooperates with a second fluid coupling member  70  which in the embodiment illustrated in  FIGS. 3 to 6  is provided at the carriage  24 . Whereas is such embodiments the second fluid coupling member  70  is connected preferably via a flexible hose  72  to a fluid line of the household appliance, the second fluid coupling member also could be fixedly provided at the housing  15  to engage the first fluid coupling member  68  via an aperture provided in the carriage, wherein a fluid coupling thus is established when the tank is moved into the use position, rather than when inserting the tank into the carriage. In any event, the fluid coupling preferably is configured to seal the respective coupling members, and in particular the first fluid coupling member  68  so as to prevent liquid from leaving the tank  12  when the tank is removed from the carriage  24 . 
     As illustrated in  FIGS. 3 to 6 , the household appliance preferably is equipped with a damper  74  for slowing the movement of the carriage  24  before the tank  12  reaches the servicing position. Damper  74  which provides for a smooth stop of tank  12  when it reaches its servicing position may comprise for example a hydraulic damper, a linear friction damper, a rotary damper or the like. 
     While in  FIGS. 3 to 6 , the damper  74  is shown to be connected to the carriage  24  via attachment  32  and hence provides for dampening over the entire range of movement of the carriage  24 , the damper  74  also can be designed to come into action only towards the end of travel of carriage  24 . 
     Referring again to  FIG. 2 , tank  12  preferably is provided with a handle, such as a recessed grip  76 , which facilitates manipulating the tank during removal of the tank from the household appliance, and when inserting the tank back into the receptacle  14  and further into the carriage  24 . 
     The household appliance described above and claimed herein provides for an easy to use removable tank system for a household appliance, wherein a removable tank can be ejected from the household appliance simply by pressing an activation button. While releasing the tank form its use position causes a displacement of the tank into a servicing position in which the tank is ejected so as to expose a fill opening, the tank can be easily removed from the household appliance simply by manually gripping the tank and pulling the tank further in the direction of ejection of the tank. After having filled or emptied the tank, the tank can be easily pushed back into the household appliance, so that the tank first is brought into engagement with the carriage, and by pushing further in the same direction, is fully inserted into its use position against the biasing force of a spring, which when again activating the release means provides for ejection of the tank. 
     The system suggested herein can be easily implemented and hence provides for a cost effective and reliable solution that is easy to use. 
     REFERENCE SIGNS 
     
         
           10  oven 
           12  water tank 
           14  receptacle 
           15  housing 
           16  aperture 
           18  front panel 
           20  cover element 
           22  fill opening 
           24  carriage 
           26  direction of movement 
           28  guide rails 
           30  compression spring 
           32  attachment of  30  at  24   
           34  seat 
           36  catch 
           38  locking member 
           40  piston 
           42  ramp surface 
           44  biasing spring 
           46  solenoid actuator 
           47  controller 
           48  switch 
           50  switch 
           52  switch 
           54  button element 
           55  wire harness 
           56 ,  57  contacts 
           58  rotatable latch 
           59  wires 
           60  biasing spring 
           61  first leg of  58   
           62  push rod 
           64  push button 
           66  leg 
           68  first fluid coupling member 
           70  second fluid coupling member 
           72  flexible hose 
           74  damper