Patent Publication Number: US-9901239-B2

Title: Dishwasher, in particular household dishwasher

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a dishwasher, in particular a household dishwasher. 
     In a dishwasher a firm connection of the components between the washing compartment and a base support arranged below said washing compartment is important in order to distribute forces in an advantageous manner within the dishwasher when a force which is produced as a result of operation or another external force, namely during transport, is introduced. 
     A dishwasher is disclosed in DE 44 38 085 C2, the washing compartment thereof being surrounded on its front access opening by a front frame which is open on the floor side and welded to the washing compartment. The front frame comprises lateral frame strips which are supported at the front corner regions on hinge plates which in turn are held in the base support on the floor side. The appliance door is pivotably articulated to the hinge plates. 
     The vertical frame strips of the front frame and the hinge plates are, therefore, connected together at a connection point which serves as a junction point for introducing operating forces or other external forces and which has to withstand said forces. In order, therefore, to configure the connection point with a correspondingly high degree of structural rigidity, both the consumption of materials and the cost in terms of mounting technology are high. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a dishwasher, in particular a household dishwasher, in which a simple and yet operationally reliable assembly of the dishwasher is possible. 
     The object is achieved by the features of claim  1 . Preferred developments of the invention are disclosed in the sub-claims. 
     According to the invention, the front frame enclosing the front access opening of the washing compartment comprises lateral frame strips, which preferably are attached at their lower ends to bearing elements, in particular hinge plates, of a base support on the floor side. Additionally, in the known manner the appliance door is articulated to the hinge plates about a horizontal pivot axis. Each of the frame strips of the front frame comprises at least one hook element which encompasses the bearing element of the base support. By means of the hook element, it is ensured in a simple manner that the respective frame strip remains joined to the associated bearing element, i.e. the hinge plate, and permanently provides a structurally rigid double wall structure. Thus, according to the invention a connection point may be achieved between the front frame and the hinge plate which has a high degree of structural rigidity and dispenses with further separate connecting elements. 
     According to an advantageous development of the invention, the respective hook element may be configured in the same material and integrally with the respective frame strip of the front frame and, in particular, protrude from a base portion of the frame strip expediently with a hooked projection which merges with an angled hooked limb. Said hooked limb is spaced apart by a clearance from the base portion of the frame strip, forming a centering gap. The centering gap of the hook element in the mounting direction of the washing compartment may be expediently designed, for example, to be downwardly open in the vertical direction. As a result, the hook element is able to encompass the hinge plates when the washing compartment is put in place, whereby said two elements are fixed relative to one another in the lateral direction of the appliance. The clear centering height of the hook element thus preferably corresponds approximately to the wall thickness of the frame strip region encompassed by the hook element. 
     The invention is explained hereinafter by way of example with reference to a connection point between a frame strip of the front frame and a bearing element designed as a hinge plate. However, it is only of subsidiary importance to the invention that the frame strip is supported on a hinge plate. Instead, the frame strip may be supported on bearing elements of any design. 
     If the centering gap of the hook element is designed to be downwardly open in the vertical direction, an upper edge of the hinge plate may be directly inserted into the centering gap. The insertion of the hinge plate-upper edge in the centering gap preferably takes place by a positive connection, optionally with slight freedom of movement. As a result, the joining process may be carried out without resilient or plastic deformation of the frame strip or the hinge plate as, for example, would be the case with a latching connection, in which a latching element is able to engage behind an undercut of a mating element only by elastic, resilient deformation. 
     In the assembled position, the hinge plates are arranged in the lateral direction of the appliance on the outside of the frame strips of the front frame and, in particular, bear flush against the hinge plates. As a result, in the assembled position the washing compartment may be supported without clearance in the lateral direction of the appliance. 
     The frame strip may preferably comprise at least one height stop via which the front frame is able to be supported on a mating element of the hinge plate. Additionally, the frame strip may additionally comprise a depth stop or separately therefrom preferably at least one depth stop, which may be brought to bear in the overall depth direction against a mating element of the hinge plate. The mating elements formed on the hinge plate of the height stop or depth stop are preferably edges of an aperture-like recess provided in the hinge plate. The height stop or depth stop may preferably protrude outwards, starting from the aforementioned base portion of the frame strips in the lateral direction of the appliance and in the assembled position may be inserted into the respective recess on the hinge plate. 
     When the washing compartment is still unmounted, the hinge plate may be initially mounted with clearance in the base support. A permanent engagement between the height/depth stop and the recesses of the hinge plate may, therefore, only be ensured by means of the hook element according to the invention which blocks an outward deflection of the hinge plate with clearance in the lateral direction of the appliance. Additional screw connections, which assist a fixed connection of the frame strip to the hinge plate, may be omitted so as to reduce the number of components. 
     The shape of the frame strip of the front frame is, in particular, designed to be of U-shaped profile with a base portion, already mentioned, as well as edge flanges bent back therefrom. In an advantageous variant of the hook element, at the transition point i.e. in the corner region, a downwardly open centering gap may be provided between the base portion and one of the edge flanges. During assembly, the upper edge of the hinge plate may be inserted into the centering gap and brought to bear against the frame strip-base portion in the lateral direction of the appliance. In order to simplify the assembly further, the downwardly open centering gap may comprise an insertion region with a widened gap width. The chamfered edge defining the insertion region may extend in the vertical direction of the appliance upward in the direction of the base portion, whereby the gap width of the insertion region may be reduced approximately up to a wall thickness of the hinge plate region to be inserted into the centering gap. In particular, the chamfered edge may be contoured in the insertion region of the centering gap such that during assembly the hinge plate is automatically guided to bear flat against the edge strip. 
     It is preferable if the hook element according to the invention is only provided for positioning the washing compartment in the lateral direction of the appliance, whilst the edge strip itself is supported in-situ on the hinge plate independently of the hook element. In view of this, it may be expedient if in the assembled position the aforementioned hooked projection of the hook element is spaced apart from the upper edge of the hinge plate by a clear height difference. 
     The advantageous embodiments and/or developments of the invention explained above and/or reproduced in the sub-claims, in this case—apart for example in the case of specific dependencies or incompatible alternatives—may be used individually or also in any combination with one another. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention and the advantageous embodiments and developments thereof, as well as the advantages thereof are explained in more detail hereinafter with reference to the drawings, in which: 
         FIG. 1  shows in a perspective principal view the front, right-hand side corner region of a supporting structure of a dishwasher; 
         FIG. 2  shows in an enlarged view a connection point between a front frame of the washing compartment and a hinge plate held in the base support; and 
         FIG. 3  shows a view according to  FIG. 2  but in an exploded view. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION 
     In  FIG. 1  the lower right-hand side front corner region of a dishwasher is shown in a principal view, the outer housing thereof being omitted and a door  51  shown in broken lines. Additionally, in  FIG. 1  appliance components which do not contribute to understanding the invention have also been omitted for the sake of clarity. The left-hand, lower front corner region, not shown, is designed to be mirror-symmetrical relative to a vertical center axis. 
     Accordingly, the dishwasher comprises a box-shaped washing compartment  3  which may be produced from sheet metal plates welded together and an access opening  5  which is open on the front side and which may be closed by the appliance door. The front access opening  5  of the washing compartment  3  is surrounded in a manner known per se by a front frame  7 , which is welded in the manner of a supporting element to the outside of the washing compartment  3 . The front frame  7  has vertically arranged lateral frame strips  9  which are connected on the upper face to a transversely extending frame strip. The front frame  7  is designed to be U-shaped in profile with a base portion  10  as well as frame flanges  11  bent back outwardly to the side. The access opening  5  is not completely surrounded by the front frame  7 , but instead the lateral frame strips  9  comprise ends  15  which are downwardly open and which are supported on hinge plates  17 . Said hinge plates are inserted in each case in a mounting shaft  19  of a trough-shaped base support  21 . Additionally, the base support  21  has on its rear corner regions supporting contours, not shown in more detail, which in the rear region carry the washing compartment  3 . Moreover, in the lateral direction x of the appliance, hinge levers, not shown, are articulated to both hinge plates  17  on the outside, said hinge levers being mounted on the appliance door. 
     In  FIG. 2  the connection point A between the frame strip  9  of the front frame  7  as well as the hinge carrier plate  17  are shown enlarged. Accordingly, the hinge plate  17  comprises a limb  25  protruding vertically upward and which is arranged in  FIG. 2  between the two edge flanges  11  of the frame strip  9 . In the vertical limb  25  of the hinge plate, aperture-like recesses  27 ,  28  are incorporated, into which in each case a depth stop  29  and a height stop  30  of the frame strip  9  are inserted. The height stop and depth stop  29 ,  30  are stamped as embossed portions in the base portion  10  of the frame strip  9 . According to  FIG. 4 , the depth stop  29  in this case cooperates in the overall depth direction y with the vertical edges  31 ,  32  of the recess  27  virtually without play. In contrast, the height stop  30  cooperates with the horizontal edges  33 ,  34  of the upper recess  28 . Accordingly, the washing compartment  3  is supported at the front by its own weight F G  via the two lateral height stops  30  on the lower edge  34  of the recess  28  in the vertical hinge plate limb  25 , whereby the weight F G  is introduced into the hinge plate  17 . The overlap between the height stop  30  and the lower edge  34  of the recess  28  is relatively small and, depending on the plate thickness, approximately 3 to 7 mm. The same also applies to the overlap provided in the overall depth direction y between the depth stop  29  and the lateral vertical edges  31 ,  32 . In order to ensure a permanent engagement of the height/depth stops here, the lower end  15  of the frame strip  9  is formed with additional hook elements  35 ,  36 , which in each case comprise a centering gap  37  which is downwardly open in the vertical direction z, in which in each case the vertical hinge plate limb  25  is inserted with its upper edge  38 . Accordingly, both the hook element  35  and the hook element  36  in each case overlap the upper edge  38  of the vertical hinge plate limb  25 . The centering gap  37  is in this case designed so that the vertical hinge plate limb  25  bears tightly against the base portion  10  of the frame strip  9 . Accordingly, the clearance a of the hook element  35  shown in  FIG. 3  is identical to the contour, predetermined by the cup-like portion  41 , on the upper edge  38  and the clearance of the hook element  36  is identical to the wall thickness of the hinge plate  17 . 
     The hook element  35  is an angled sheet-metal flap which is bent out of the cut-out  43  in the base portion  10  of the frame strip  9 . Accordingly, the hook element  35  has a hooked projection  44  protruding horizontally outwards approximately at right angles in the lateral direction x of the appliance, which merges with a downwardly angled hooked limb  45 . The hooked limb  45  is, as already mentioned above, spaced apart from the base portion  10  of the frame strip  9  by the clearance a. Additionally, the hooked projection  44  is spaced apart from the upper edge  38  of the hinge plate limb  25  in the assembled state by the height difference Δh, so as not to provide an additional force path for introducing weight forces. 
     The second hook element  36  of the frame strip  9  is produced by the rear edge flange  11  of the front frame  7  in the overall depth direction y. The edge flange  11  according to  FIG. 3  is provided at the transition with the base portion  10  with the centering gap  37 , which in the vertical direction z merges downwardly with a widened insertion region  47 . The insertion region  47  is defined by a chamfered edge  49  which reduces the gap width, starting from the lower end of the edge flange  11  as far as the centering gap  37  itself. 
     Additionally, the vertical hinge plate limb  25  at the front comprises a bent-back edge flange  50  which in the installed position ( FIG. 1 or 2 ) is connected by a screw connection  48  to the front frame flange  11  of the front frame  7  in order to ensure grounding. The screw connection  48 , however, does not fulfill any centering function and, therefore, does not have any significance for the invention. 
     In  FIG. 3 , the frame strip  9  is dismantled from the vertical hinge plate limb  25  shown. When assembling the washing compartment  3  to the base sub-assembly, the front frame  7  is placed in the joining direction F on the vertical hinge plate limb  25 . In this case, the upper edge  38  of the hinge plate limb  25  is inserted into the centering gaps  37  of the two hook elements  35 ,  36 . In order to simplify the assembly, a rough alignment of the washing compartment is sufficient relative to the base sub-assembly so that the upper edge  38  of the limb  25  initially strikes against the contact surface  49  in the rear edge flange  11  of the front frame  7  and in a subsequent step is guided thereby to bear against the base portion  10  of the frame strip  17 . At the same time, the upper edge  38  is also inserted into the centering gap  37  of the first hook element  35 , which is slightly upwardly displaced in comparison with the hook element  36 . With this insertion movement, the height stop and depth stop  30 ,  31  are brought into engagement with the associated recesses  27 ,  28  in the hinge plate limb  25 . As a result, in a manner which is simple in terms of mounting technology, a connection of the washing compartment  3  to the base sub-assembly is produced which results in a structurally rigid front corner region without separate fastening means.