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RELATED APPLICATION  
       [0001]     This application is a continuation application of PCT/EP2005/009971 filed Sep. 16, 2005, the entire specification of which is incorporated herein by reference. 
     
    
     FIELD OF DISCLOSURE  
       [0002]     The present invention relates to a sink accessory which is adapted to be placed on a sink, wherein the sink accessory comprises at least one first bearing surface with which the sink accessory is adapted to be placed on at least one supporting surface of the sink.  
       BACKGROUND  
       [0003]     Such sink accessories are known from the state of the art and are, for example, in the form of cutting boards which are fixable to the sink at a defined working position or are guided on the sink in displaceable manner in a direction of displacement.  
       SUMMARY OF THE INVENTION  
       [0004]     The object of the present invention is to provide a sink accessory of the type mentioned hereinabove which is usable in a versatile manner.  
         [0005]     In accordance with the invention, this object is achieved in the case of a sink accessory comprising the features indicated in the first part of Claim  1  in that the sink accessory comprises at least one second bearing surface with which the sink accessory is adapted to be placed on a supporting surface of a sink or on a supporting surface of another sink accessory, wherein the second bearing surface of the sink accessory is arranged at a different height level of the sink accessory than the first bearing surface.  
         [0006]     This arrangement in accordance with the invention enables the geometry of the first bearing surface to be adapted to the geometry of a first supporting surface of the sink so that the sink accessory is positionable on the sink at a first working position, and also enables the geometry of the second bearing surface of the sink accessory to be adapted to the geometry of a second supporting surface which may be formed on the same sink, on another sink or on another sink accessory in order to position the sink accessory on the same sink, on another sink or on another sink accessory at a second working position which is different from the first working position.  
         [0007]     In this way, it is possible to selectively place one and the same sink accessory on different supporting surfaces of the same sink, on the supporting surfaces of different sinks or on the supporting surface of another sink accessory such as a strainer for example.  
         [0008]     The sink accessory in accordance with the invention can thus also be used, in particular, on several mutually differing sinks which have mutually differing dimensions.  
         [0009]     Furthermore, the sink accessory in accordance with the invention can be stacked on other sink accessories, for example, on drainers and strainers.  
         [0010]     In addition to the first bearing surface and the second bearing surface, the sink accessory in accordance with the invention may also comprise yet further bearing surfaces at other height levels in order to increase the versatility of the sink accessory still further.  
         [0011]     The sink, on which the sink accessory is adapted to be placed, may comprise one or more sink bowls and be formed with or without a drainage surface.  
         [0012]     In this description and in the attached Claims, the term “sink” also covers any possible work top upon which a sink bowl is arranged.  
         [0013]     In particular, the sink can comprise a work top incorporating a work top cut-out and a sink bowl in the form of a built-under bowl arranged on the lower surface of the work top. In this case, the supporting surface of the sink upon which the sink accessory is adapted to be placed is formed on the work top. The construction of the sink accessory in accordance with the invention enables one and the same sink accessory to be used with different sinks having work top cut-outs of mutually differing internal dimensions.  
         [0014]     In a preferred embodiment of the sink accessory, provision is made for the sink accessory to comprise at least one first positioning surface which cooperates with a positioning surface of the sink when a sink accessory is placed on the sink, and at least one second positioning surface which cooperates with a positioning surface of the sink or that of another sink accessory when the sink accessory is placed on the same sink or on another sink or on the other sink accessory, wherein the second positioning surface is arranged at a different height level of the sink accessory than the first positioning surface.  
         [0015]     Hereby, the first positioning surface of the sink accessory can, for example, be a guidance surface which cooperates with a guidance surface of the sink when the sink accessory is placed on the sink in order to guide the sink accessory in the course of a displacement relative to the sink along a direction of displacement.  
         [0016]     The first positioning surface can also be formed as a stop surface which cooperates with a stop surface of the sink when the sink accessory is placed on the sink in order to limit the displacement path of the sink accessory relative to the sink or to fix the sink accessory in a working position relative to the sink.  
         [0017]     In this description and the attached Claims, the term “fixing” is not to be understood as meaning fastening, but rather, as defining the relative position of two elements in at least one direction, apart that is, from a small amount of play between the two elements.  
         [0018]     The size of this play between the elements involved is usually due to the constructional tolerances of these elements (i.e. for example, the sink accessory and the sink).  
         [0019]     The second positioning surface of the sink accessory and the positioning surfaces of the sink or of the other sink accessory can likewise be in the form of guidance and/or stop surfaces.  
         [0020]     In addition to the first positioning surface and the second positioning surface, the sink accessory may also comprise yet more positioning surfaces at other height levels in order to increase the versatility of the sink accessory still more.  
         [0021]     In order to enable the sink accessory to be used with sinks and/or other sink accessories each of which comprises several positioning surfaces that cooperate with the sink accessory and wherein the mutual spacings between these positioning surfaces are different, provision is preferably made for the sink accessory to comprise at least two first positioning surfaces which are arranged at the same height level of the sink accessory and both of which extend along the same direction of the sink accessory and are spaced from each other in a direction perpendicular to this direction, and at least two second positioning surfaces which are likewise arranged at the same height level although this is different from the height level of the first positioning surfaces of the sink accessory, and which extend along the same direction of the sink accessory and are spaced from each other in a direction perpendicular to this direction, wherein the second positioning surfaces are at a different distance from each other than the first positioning surfaces.  
         [0022]     Hereby for example, the first and the second positioning surfaces can be in the form of guidance surfaces and/or stop surfaces of the sink accessory.  
         [0023]     In particular, provision may be made for the second positioning surfaces to be arranged at a lower height level of the sink accessory than the first positioning surfaces.  
         [0024]     Furthermore, provision can be made for the second positioning surfaces to be at a smaller spacing from each other than the first positioning surfaces.  
         [0025]     In a preferred embodiment of the sink accessory, provision is made for the sink accessory to comprise at least two first positioning surfaces which are both arranged at the same height level of the sink accessory and are oriented transversely, preferably substantially perpendicularly, to one another, and also at least two second positioning surfaces which are likewise arranged at the same height level of the sink accessory but at one that is different from the height level of the first positioning surfaces, and said second surfaces are oriented transversely, preferably substantially perpendicularly, to one another.  
         [0026]     In this case, one of the first positioning surfaces and/or one of the second positioning surfaces of the sink accessory can serve, in particular, as a guidance surface and the other first positioning surface or second positioning surface that is oriented transversely to the guidance surface can serve as a stop surface of the sink accessory.  
         [0027]     In particular, the bearing surfaces and the positioning surfaces of the sink accessory can border one another in such a manner that, together, they form positioning steps (guide steps and/or stop steps) of the sink accessory.  
         [0028]     Provision may be made, in particular, for at least one first bearing surface and one first positioning surface of the sink accessory to border one another and together, to form a first positioning step of the sink accessory.  
         [0029]     Alternatively or in addition thereto, provision may be made for at least one second bearing surface and at least one second positioning surface of the sink accessory to border one another and together, to form a second positioning step of the sink accessory.  
         [0030]     In a preferred embodiment of the sink accessory, provision is made for the sink accessory to comprise at least one positioning element which comprises at least one first bearing surface and at least one second bearing surface, wherein the first bearing surface and the second bearing surface are arranged at different height levels of the positioning element.  
         [0031]     Furthermore, provision may be made for the sink accessory to comprise at least one positioning element which comprises at least one first positioning surface and at least one second positioning surface, wherein the first positioning surface and the second positioning surface are arranged at different height levels of the positioning element.  
         [0032]     Such a positioning element can be in the form of a foot part of the sink accessory for example.  
         [0033]     As an alternative thereto, provision may also be made for the positioning element to be in the form of a strip which extends along a lateral edge of the sink accessory.  
         [0034]     In principle, the positioning element can be formed in one piece manner with a base body of the sink accessory.  
         [0035]     In a preferred embodiment of the invention however, provision is made for the positioning element to be in the form of a component that is manufactured separately from a base body of the sink accessory and is attached to the base body.  
         [0036]     The positioning element can, in principle, be attached to the base body in any arbitrary manner, for example, by means of securing bolts.  
         [0037]     Provision is preferably made however for the at least one positioning element to be adhered to the base body.  
         [0038]     In this case it is of advantage if the positioning element comprises at least one recess for accommodating an adhesive.  
         [0039]     In order to prevent unwanted bowing of the bearing surface of the positioning element, the positioning element can be provided with at least one spacer which is arranged in the region of the recess for the accommodation of the adhesive.  
         [0040]     If the base body of the sink accessory comprises at least one substantially transparent region, then it is expedient furthermore for the base body to comprise at least one substantially non-transparent region and for the at least one positioning element to be attached to the substantially non-transparent region of the base body in order to prevent the positioning element from being visible through the transparent region of the base body.  
         [0041]     The sink accessory in accordance with the invention can, in principle, exhibit any arbitrary function, for example, it may be in the form of a drainage sheet, a drainage rack, a grater, a plane, a strainer or the like.  
         [0042]     In a preferred embodiment of the invention, the sink accessory is in the form of a cutting board.  
         [0043]     Claim  19  is directed toward the combination of a sink and a sink accessory in accordance with the invention that is adapted to be placed on the sink.  
         [0044]     Claim  20  is directed toward the combination of a sink, a sink accessory in accordance with the invention that is adapted to be placed on the sink and another sink accessory upon which the sink accessory in accordance with the invention is likewise adapted to be placed.  
         [0045]     In the case of this combination, the other sink accessory can, in particular, be a container that is adapted to be hung on the sink.  
         [0046]     Further features and advantages of the invention form the subject matter of the following description and the graphic illustration of exemplary embodiments. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0047]      FIG. 1  shows a plan view of a sink from above, wherein a sink bowl is inserted into a work top cut-out;  
         [0048]      FIG. 2 a  plan view of the sink in  FIG. 1  from above, wherein a cutting board is placed on the sink bowl;  
         [0049]      FIG. 3 a  partial vertical longitudinal sectional view through the sink in  FIG. 2  and the cutting board placed on the sink;  
         [0050]      FIG. 4 a  plan view of the sink in  FIG. 1  from above, wherein a strainer is hung in the sink;  
         [0051]      FIG. 5 a  plan view from above of the sink in  FIG. 4  wherein a cutting board is placed on the strainer;  
         [0052]      FIG. 6 a  partial vertical longitudinal sectional view through the sink in  FIG. 5  with the strainer hung in the sink bowl and the cutting board placed on the strainer;  
         [0053]      FIG. 7 a  schematic plan view of the cutting board from below;  
         [0054]      FIG. 8 a  schematic perspective illustration of the lower surface of a corner of the cutting board with a positioning element arranged on the lower surface of the cutting board;  
         [0055]      FIG. 9 a  partial vertical longitudinal sectional view through the cutting board with the positioning element arranged thereon;  
         [0056]      FIG. 10 a  schematic perspective illustration of the positioning element in  FIG. 8 ;  
         [0057]      FIG. 11 a  schematic vertical longitudinal sectional view through the positioning element in  FIG. 10 ;  
         [0058]      FIG. 12 a  partial vertical longitudinal sectional view through a second embodiment of a sink with a cutting board placed on the sink, wherein the cutting board rests upon the work top; and  
         [0059]      FIG. 13 a  partial vertical longitudinal sectional view through the sink in  FIG. 12  with a strainer hung in the work top cut-out and a cutting board placed on the strainer. 
     
    
       [0060]     Similar or functionally equivalent elements are designated by the same reference symbols in all of the Figures.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0061]     A sink bearing the general reference  100  that is illustrated in FIGS.  1  to  6  comprises a sink bowl  102  incorporating a bowl base  104  provided with a bowl discharge opening  106  therein, and also incorporating front and rear bowl side walls  108   a,    108   b  as well as left and right bowl side walls  108   c,    108   d  which extend substantially vertically upwardly from the bowl base  104  and also incorporating a substantially horizontally oriented peripheral bowl flange  110  which extends along the upper edges of the bowl side walls  108   a  to  108   d.    
         [0062]     As can best be seen from  FIG. 3 , the lower surface of the bowl flange  110  rests on the upper surface  112  of a work top  114  which is provided with a work top cut-out  116  into which the sink bowl  102  is inserted.  
         [0063]     As can best be seen from  FIG. 2 , two strip-like sections of the upper surface  120  of the bowl flange  110  that extend in the longitudinal direction  118  of the sink  100  (parallel to the front and rear bowl side walls  108   a,    108   b ) form two supporting surfaces  122   a,    122   b  of the sink which extend in the longitudinal direction  118  of the sink  100  and are spaced from one another in the transverse direction  124  of the sink  100  that is oriented perpendicularly to the longitudinal direction  118 .  
         [0064]     The supporting surfaces  122   a,    122   b  serve for supporting sink accessories that are adapted to be placed on the sink  100  or hung in the sink bowl  102 , for example, for the purposes of supporting the cutting board  126  that is illustrated in  FIG. 2 .  
         [0065]     The cutting board  126  is illustrated in detail in FIGS.  7  to  11 .  
         [0066]     It comprises a substantially rectangular platter  128  made of glass or of a preferably transparent, synthetic material for example.  
         [0067]     The platter  128  comprises mutually opposed long edges  130  whose length substantially corresponds to the extent of the sink bowl  102  in the transverse direction  124  of the sink  100 , and also two mutually opposed short edges  132  whose length is significantly smaller than the extent of the sink bowl  102  in the longitudinal direction  118  of the sink  100 .  
         [0068]     The platter  128  is provided on the lower surface  134  thereof in the region of two strips  136  which run adjacent to the short edges  132  of the platter  128  with a coating consisting of an opaque material that can be applied by imprinting on the platter  128  for example.  
         [0069]     Furthermore, the cutting board  126  is provided with four positioning elements  138  which are attached to the platter  128  in a respective corner area of the lower surface  134  of the platter  128 .  
         [0070]     The structure of these positioning elements  138  can best be seen from FIGS.  8  to  11 .  
         [0071]     Each of the positioning elements  138 , which are all of identical construction, comprises a substantially rectangular parallelepiped lower part  140  having a horizontal lower surface  142  (see in particular  FIG. 10 ), a central part  144  which adjoins the lower part  140  at that side of the lower part remote from the lower surface  142  and which is likewise in the form of a substantially rectangular parallelepiped and projects up from the lower part  140  on three sides, and also an upper part  146  which adjoins the central part  144  at that side of the central part  144  remote from the lower part  140  and is approximately in the form of a rectangular parallelepiped and which projects up from the central part  144  on three sides.  
         [0072]     The lower surface of the upper part  146  facing the central part  144  forms a first bearing surface  148  of the positioning element  138 .  
         [0073]     This bearing surface  148  comprises a middle section  150  in which the bearing surface  148  is inclined in a direction running in the longitudinal direction  152  of the positioning element  138 , whereby this inclination is arranged in such a manner that the outer edge  154  of the bearing surface  148  is somewhat higher than the inner edge  156  thereof.  
         [0074]     Hereby, the angle of inclination between the first bearing surface  148  and the horizontal preferably amounts at most to approximately 10°, for example, approximately 3°.  
         [0075]     Two lateral sections  158  of the first bearing surface  148  are inclined in the transverse direction  160  of the positioning element  138  that is oriented perpendicularly relative to the longitudinal direction  152 , i.e. in such a manner that the outer edge  154  of the first bearing surface  148  is also somewhat higher than the inner edge  156  of the first bearing surface  148  in these lateral sections  158  of the first bearing surface  148  as well.  
         [0076]     Preferably, the angle of inclination between the first bearing surface  148  and the horizontal in these lateral sections  158  also amounts at most to approximately 10°, for example, approximately 3°.  
         [0077]     At the inner edge  156  thereof, the middle section  150  of the first bearing surface  148  changes into a substantially vertical first guidance surface  162  of the positioning element  138  which extends in the transverse direction  160  of the positioning element  138  and forms a lateral boundary of the central part  144  of the positioning element  138 .  
         [0078]     At the inner edge  156  thereof, each of the lateral sections  158  of the first bearing surface  148  changes into a substantially vertical first stop surface  164  of the positioning element  138  which extends in the longitudinal direction  152  of the positioning element  138  and likewise forms a lateral boundary of the central part  144  of the positioning element  138 .  
         [0079]     The first guidance surface  162  and the first stop surfaces  164  of the positioning element  138  are located at the same height level of the positioning element  138 , i.e. at the same distance from the lower surface  142  of the lower part  140  and from the upper surface  196  of the upper part  146  of the positioning element, whereby the first guidance surface  162  is connected to the first stop surfaces  164  by convexly curved corner areas  166 .  
         [0080]     A substantially horizontally oriented second bearing surface  170 , which forms a lower boundary of the central part  144  of the positioning element  138 , adjoins those lower edges  168  of the first guidance surface  162  or of the first stop surfaces  164  that are remote from the first bearing surface  148 .  
         [0081]     The second bearing surface  170  comprises a middle section  172  which borders on the first guidance surface  162  and also two lateral sections  174  which border on a respective one of the first stop surfaces  164 .  
         [0082]     A substantially vertical second guidance surface  178  of the positioning element  138 , which extends in the transverse direction  160  of the positioning element  138  and forms a lateral boundary of the lower part  140  of the positioning element  138 , adjoins the inner edge  176  of the middle section  172  of the second bearing surface  170 .  
         [0083]     A respective, substantially vertically oriented second stop surface  180  of the positioning element  138 , which extends in the longitudinal direction  152  of the positioning element  138  and likewise forms a lateral boundary of the lower part  140  of the positioning element  138 , adjoins the inner edges  176  of the lateral sections  174  of the second bearing surface  170 .  
         [0084]     The second guidance surface  178  and the two second stop surfaces  180  of the positioning element  138  are arranged at the same height level of the positioning element  138 , whereby the second guidance surface  178  is connected to the second stop surfaces  180  by convexly curved corner areas  182 .  
         [0085]     The substantially horizontally oriented lower surface  142  of the positioning element  138  adjoins the second guidance surface  178  or the second stop surfaces  180  at the lower edges  184  thereof.  
         [0086]     The positioning element  138  thus has a stepped-pyramid-like structure, wherein the first guidance surface  162  and the middle section  150  of the first bearing surface  148  together form a first guidance step  186 , the second guidance surface  178  and the middle section  172  of the second bearing surface  170  together form a second guidance step  188 , each of the first stop surfaces  164  together with one of the lateral sections  158  of the first bearing surface  148  forms a respective first stop step  190  and each of the second stop surfaces  180  together with a respective lateral section  174  of the second bearing surface  170  forms a respective second stop step  192 .  
         [0087]     As can best be seen from the longitudinal sectional view in  FIG. 11 , each of the positioning elements  138  is provided with a stepped recess  194  which extends downwardly from the upper surface  196  of the upper part  146  into the central part  144  and the lower part  140  of the positioning element  138 .  
         [0088]     Furthermore, the positioning element  138  is provided with a shallower adhesive holding recess  198  which extends from the region of the upper surface  196  of the positioning element  138  located opposite the first bearing surface  148  into the upper part  146  of the positioning element  138 .  
         [0089]     A plurality of spacer domes  200 , which extend upwardly from the bottom of the adhesive holding recess  198 , are arranged in the adhesive holding recess  198 .  
         [0090]     In order to attach the positioning element  138  to the lower surface  134  of the platter  128  of the cutting board  126  by means of an adhesion process, the adhesive holding recess  198  is filled with a suitable adhesive and then the upper surface  196  of the upper part  146  of the positioning element  138  is pressed against the lower surface  134  of the platter  128 , whereby the spacer domes  200  prevent unwanted bowing of the first bearing surface  148 .  
         [0091]     The positioning elements  138  are adhered to the platter  128  in the region of the opaque strips  136  so that the recesses  194 ,  198  of the positioning elements  138  remain invisible from the upper surface  202  of the cutting board  126  even if the platter  128  is made of a transparent material.  
         [0092]     As can best be seen from  FIG. 7 , the four positioning elements  138  are adhered to the lower surface  134  of the platter  128  in such a way that the longitudinal directions  152  of the positioning elements  138  are aligned parallel to the long edges  130  of the platter  128  and the transverse directions  160  of the positioning elements  138  are aligned parallel to the short edges  132  of the platter  128 .  
         [0093]     The first guidance surfaces  162  of the positioning elements  138  thus form first guidance surfaces  162  of the cutting board  126  which extend in the transverse direction  204  of the cutting board  126  and are spaced from each other in pairs in the longitudinal direction  206  of the cutting board  126 .  
         [0094]     In like manner, the second guidance surfaces  178  of the positioning elements  138  form respective second guidance surfaces  178  of the cutting board  126  which extend in the transverse direction  204  of the cutting board  126  and are respectively spaced from each other in pairs in the longitudinal direction  206  of the cutting board  126 , whereby the mutual spacing d 2  between the second guidance surfaces  178  in the longitudinal direction  206  is smaller than the mutual spacing d 1  between the first guidance surfaces  162  in the longitudinal direction  206  of the cutting board  126 .  
         [0095]     The first stop surfaces  164  of the positioning elements  138  facing the outer edges of the platter  128  form respective first stop surfaces  164  of the cutting board  126  which extend in the longitudinal direction  206  of the cutting board  126  and are spaced from each other in pairs in the transverse direction  204  of the cutting board  126 .  
         [0096]     In like manner, the second stop surfaces  180  of the positioning elements  138  facing the outer edges of the platter  128  form second stop surfaces  180  of the cutting board  126  which extend in the longitudinal direction  206  of the cutting board  126  and are spaced from each other in the transverse direction  204  of the cutting board  126 , whereby the mutual spacing s 2  between the second stop surfaces in the transverse direction  204  is smaller than the mutual spacing s 1  between the first stop surfaces  164  in the transverse direction  204  of the cutting board  126 .  
         [0097]     The positioning elements  138  can be manufactured as injection moulded parts of synthetic material for example.  
         [0098]     As can be seen from  FIGS. 2 and 6 , the cutting board  126  is placed on the sink  100  in such a way that the longitudinal direction  206  of the cutting board  126  is aligned in parallel with the transverse direction  124  of the sink and the transverse direction  204  of the cutting board  126  is aligned in parallel with the longitudinal direction  118  of the sink  100 , and the upper surface  202  of the cutting board  126  is oriented horizontally.  
         [0099]     The cutting board  126  thereby rests upon the supporting surfaces  122   a,    122   b  of the sink  100  by means of the first bearing surfaces  148  of the positioning elements  138 .  
         [0100]     Due to the inclination of the first bearing surfaces  148  with respect to the horizontal, the first bearing surfaces  148  do not rest flatly against the supporting surfaces  122   a,    122   b,  but rather, they are in line contact therewith, this thereby facilitating the displacement of the cutting board  126  relative to the supporting surfaces  122   a,    122   b.    
         [0101]     Hereby, the first guidance surfaces  162  of the cutting board  126  cooperate with the upper edge regions of the bowl side walls  108   a,    108   b  which form the guidance surfaces  208   a,    208   b  of the sink  100  in such a way that the cutting board  126  is guided in displaceable manner on the sink  100  in the longitudinal direction  118  of the sink, whereby the position of the cutting board  126  relative to the sink  100  in the transverse direction  124  of the sink  100  is defined, apart that is, from a slight amount of play between the first guidance surfaces  162  of the cutting board  126  and the guidance surfaces  208   a,    208   b  of the sink  100 .  
         [0102]     The cutting board  126  can be displaced in the longitudinal direction  118  of the sink  100  until the first stop surfaces  164  of the cutting board  126 , which are located at the same height level of the cutting board  126  as the first guidance surfaces  162 , strike the upper regions of one of the bowl side walls  108   c,    108   d  which extend in the transverse direction  124  of the sink  100  and form stop surfaces  210   a,    210   b  of the sink  100 .  
         [0103]     Consequently, when the cutting board  126  is placed on the sink  100 , the first stop surfaces  164  of the cutting board  126  cooperate with the stop surfaces  210   a,    210   b  of the sink  100  in such a way that the displacement path of the cutting board  126  relative to the sink  100  is limited in the longitudinal direction  118  of the sink  100 .  
         [0104]     Furthermore, a strainer  212  is adapted to be hung in the sink bowl  102  of the sink  100 .  
         [0105]     As can be seen from  FIGS. 4 and 6 , the strainer  212  comprises a container base  214  containing drainage openings  216 , long side walls  218  and short side walls  220  which extend substantially vertically upwardly from the container base  214  and also a substantially horizontal container flange  222  which extends around the periphery of the upper edges of the side walls  218 ,  220 .  
         [0106]     Angular slide elements  224  are attached, are adhered for example, to the lower surface of the container flange  222 .  
         [0107]     When it is hung in the sink bowl  102 , the strainer  212  rests with the lower surface of the slide elements  224  upon the supporting surfaces  122   a,    122   b  of the sink  100  whereby the long side walls  218  of the strainer  212  are aligned in parallel with the transverse direction  124  and the short side walls  220  of the strainer  212  are aligned in parallel with the longitudinal direction  118  of the sink  100 , and the strainer  212  is displaceable relative to the sink  100  in the longitudinal direction  118 .  
         [0108]     In order to be able to use the cutting board  126  on the sink  100  without previously having to remove the strainer  212 , and/or in order to enable the strainer  212  to be covered by means of the cutting board  126  and thereby remove the contents of the strainer  212  from an observer&#39;s view, the cutting board  126  is adapted to be placed on the strainer  212  that is hung in the sink bowl  102 , namely, in such a manner that the longitudinal direction  206  of the cutting board  126  is aligned in parallel with the long side walls  218  of the strainer  212  and the transverse direction  204  of the cutting board  126  is aligned in parallel with the short side walls  220  of the strainer  212 .  
         [0109]     Since the distance between the mutually facing short side walls  220  of the strainer  212  is smaller than the mutual spacing d 1  between the first guidance surfaces  162  of the cutting board  126  in the longitudinal direction  206  of the cutting board  126 , the cutting board  126  does not rest on the upper surface of the container flange  222  that forms a supporting surface  226  of the strainer  212  by means of the first bearing surfaces  148 , but rather, by means of the second bearing surfaces  170  of the positioning elements  138 .  
         [0110]     Furthermore, the second guidance surfaces  178  of the cutting board  126  co-operate with the upper edge regions of the short side walls  220  of the strainer  212  that form the stop surfaces  228  of the strainer  212  in such a way that the position of the cutting board  126  relative to the strainer  212  in the longitudinal direction  206  of the cutting board  126  is defined, apart that is, from a small amount of play between the second guidance surfaces  178  and the guidance surfaces  228  of the strainer  212 .  
         [0111]     In a corresponding manner, the second stop surfaces  180  of the cutting board  126  that are located at the same height level as the second guidance surfaces  178  cooperate with the upper edge regions of the long side walls  218  of the strainer  212  that form the stop surfaces  230  of the strainer  212  in such a way that the position of the cutting board  126  relative to the strainer  212  in the transverse direction  204  of the cutting board  126  is defined, apart that is, from a small amount of play between the second stop surfaces  180  of the cutting board  126  and the stop surfaces  230  of the strainer  212 .  
         [0112]     In this way, it is possible to place the cutting board  126  at a defined position on the sink  100  by means of the positioning elements  138  despite the different clearance widths of the sink bowl  102  on the one hand and the strainer  212  on the other and also to guide it thereon in displaceable manner as well as place it at a defined position on the strainer  212 .  
         [0113]     A second embodiment of a combination of a sink  100 , a cutting board  126  and a strainer  212  that is illustrated in  FIGS. 12 and 13  differs from the first combination illustrated in FIGS.  1  to  11  only in that the sink bowl  102  in the second embodiment is not inserted into a work top cut-out in the work top  114 , but rather, is in the form of a built-under bowl which is arranged to rest against the lower surface  232  of the work top  114  by means of its bowl flange  110 .  
         [0114]     In this embodiment, the supporting surfaces  122   a,    122   b  of the sink  100  which support the cutting board  126  or the strainer  212  are not formed on the upper surface of the bowl flange  110 , but rather, on the upper surface  112  of the work top  114 .  
         [0115]     In corresponding manner, the guidance surfaces  208   a,    208   b  of the sink  100  are not formed by the upper edge regions of the bowl side walls  108   a,    108   b,  but rather, by the upper edge regions of the lateral boundary surfaces  234  of the work top cut-out  116 .  
         [0116]     Furthermore, in this embodiment, the stop surfaces  210   a,    210   b  of the sink  100  are likewise formed by the upper edge regions of the boundary surfaces  234  of the work top cut-out  116 .  
         [0117]     In all other respects, the second embodiment agrees in regard to the construction and functioning thereof with the first embodiment illustrated in FIGS.  1  to  11 , and to this extent reference should be made to the preceding description thereof.

Summary:
The subject matter of the application is a sink accessory (e.g. a cutting board) that can be placed on a sink and a sink that is provided with a sink accessory of this type. Hereby, the periphery of the sink accessory comprises two differently spaced bearing surfaces which lie at different heights with respect to the surface of the sink accessory. In this way it is possible for one and the same sink accessory to be selectively placed on different supporting surfaces of the same sink, on the supporting surfaces of different sinks or on the supporting surface of another sink accessory (e.g. a strainer). In dependence on the geometry thereby, only the first bearing surface is in contact with the sink in a first position, whereas the second bearing surface is used as a contact area in the second position.