Capsule, a system for preparing a potable beverage from such a capsule and use of such a capsule in a beverage preparation device

Abstract

A capsule containing a substance for the preparation of a beverage has an aluminum capsule body and a cover sheet hermetically closing off the capsule. The capsule body has a flange with a deformable sealing ring portion with an inner wall portion extending from and contiguous with an inner base portion of the flange, an outer wall portion extending from and contiguous with an outer base portion of the flange and a bridge portion interconnecting the inner wall portion and the outer wall portion. The bridge portion is located axially spaced from the base portions of the flange. In radial cross-sectional view, a top of the bridge portion axially most remote from the base portions of the flange is flat or has a center plane curved with a radius of curvature larger than two times a wall thickness of the top of the bridge portion.

1 - 36 . (canceled) 
     
     
         37 . A system for preparing a potable beverage from a capsule using a fluid supplied under pressure into the capsule comprising:
 a beverage preparation device comprising an enclosing member for receiving the capsule, wherein the enclosing member comprises fluid injection means for supplying fluid under pressure into the capsule, wherein the beverage preparation device further comprises a closing member, such as an extraction plate, for closing the enclosing member of the beverage preparation device, wherein said enclosing member has an annular end with an annular end surface, said annular end surface optionally being provided with a plurality of radially extending open grooves;   a capsule containing a substance for the preparation of a potable beverage by extracting and/or dissolving the substance by means of supplying a fluid under pressure into the capsule, said capsule comprising:   an aluminum capsule body having a central capsule body axis, said aluminum capsule body comprising a bottom, a side wall, an outwardly extending flange and a sealing structure at said flange; and   a cover sheet attached to said flange and hermetically closing off the capsule;   wherein said sealing structure is deformable and in fluid sealing contact with said annular end surface if the capsule is positioned in said enclosing member and said enclosing member is closed by means of said closing member, at least portions of said flange and said sealing structure being clamped between said annular end surface and said closing member;   wherein said sealing structure includes a deformable sealing ring portion of said flange, said sealing ring portion projecting axially from base portions of said flange, to which said cover is attached, on a side of said base portions facing said enclosing member when said capsule is in said enclosing member, said deformable sealing ring portion comprising:   an inner wall portion extending from and contiguous with an inner base portion of said flange;   an outer wall portion extending from and contiguous with an outer base portion of said flange, said outer wall being located radially outward of and radially spaced from said inner wall portion; and   a bridge portion interconnecting said inner wall portion and said outer wall portion, said bridge portion being located axially spaced from said base portions of said flange;   wherein, in radial cross-sectional view, a top of said bridge portion axially most remote from said base portions of the flange is flat or has a center plane curved with a radius of curvature larger than two times a wall thickness of said top of said bridge portion.   
     
     
         38 . The system according to  claim 37 , wherein said annular end surface is positioned for first contacting said top of said bridge portion when said sealing ring portion is clamped between said annular end surface and said closing member. 
     
     
         39 . The system according to  claim 38 , wherein, in cross-sectional view, said top of said bridge portion is located centrally relative to said annular end surface for first contacting a central portion of said annular end surface when said sealing ring portion is clamped between said annular end surface and said closing member. 
     
     
         40 . The system according to  claim 37 , wherein at least a portion of the top of said bridge portion of the capsule has a reduced wall thickness smaller than a wall thickness of said inner and outer wall portions. 
     
     
         41 . The system according to  claim 37 , wherein, in use, the maximum fluid pressure in the enclosing member of the beverage preparation device is in the range of 6-20 bar, preferably between 12 and 18 bar. 
     
     
         42 . The system according to  claim 37 , wherein the system is arranged such that, in use, during brewing, said annular end surface exerts a force F2 on the sealing structure of the capsule to provide a sealing contact between said flange and said annular end surface, wherein F2 is in the range of 500-1500 N preferably in the range of 750-1250 N when the fluid pressure P2 in said enclosing member outside the capsule is in the range of 6-20 bar, preferably between 12 and 18 bar. 
     
     
         43 . The system according to  claim 37 , wherein the system is arranged such that, in use, prior to or at the start of brewing, said annular end surface exerts a force F on the sealing structure of the capsule to provide a sealing contact between said flange and said annular end surface, wherein F1 is in the range of 30-150 N preferably 40-150 N, more preferably 50-100 N, when the fluid pressure P1 in the enclosing member of the beverage preparation device outside the capsule is in the range of 0.1-4 bar, preferably 0.1-1 bar. 
     
     
         44 . The system according to  claim 37 , wherein the plurality of radially extending open grooves are uniformly spaced relative to each other in circumferential sense of said annular end surface. 
     
     
         45 . The system according to  claim 44 , wherein the greatest width of each groove is 0.9-1.1 mm, preferably 0.95 to 1.05 mm, more preferably 0.98 to 1.02 mm wherein a maximal height of each groove in an axial direction of the enclosing member of the beverage preparation device is 0.01-0.09 mm, preferably 0.03 to 0.07 mm, more preferably 0.045 to 0.055 mm, most preferred 0.05 mm and wherein the number of grooves is 90 to 110, preferably 96, the radial width of the annular end surface at the location of the grooves preferably being 0.05-0.9 mm, more preferably 0.2-0.7 mm and yet more preferably 0.3-0.55 mm. 
     
     
         46 . The system according to  claim 37 , wherein during use when the closing member of the beverage preparation device closes the enclosing member of the beverage preparation device, at least a portion of the enclosing member including the annular end surface can move relative to the closing member of the beverage preparation device under the effect of the pressure of the fluid in the enclosing member of the beverage preparation device towards said closing member causing said annular end surface to apply the maximum clamping force to the flange of the capsule. 
     
     
         47 . A method of preparing a potable beverage using the system of  claim 37 , the method comprising: positioning the capsule in the enclosing member of the beverage preparation device, closing the enclosing member using the closing member of the beverage preparation device, clamping at least a portion of the sealing structure between the enclosing member and the closing member of the beverage preparation device causing the sealing structure to be brought in sealing contact with the annular end surface, and supplying fluid under pressure into the capsule. 
     
     
         48 . The method according to  claim 47  wherein the maximum fluid pressure in the enclosing member of the beverage preparation device is in the range of 6-20 bar, preferably between 12 and 18 bar. 
     
     
         49 . The method according to  claim 47 , wherein during brewing, the annular end surface of said enclosing member exerts a force F2 on the sealing structure of the capsule providing a sealing contact between the outwardly extending flange of the capsule and the enclosing member of the beverage preparation device, wherein F2 is in the range of 500-1500 N preferably in the range of 750-1250 N when the fluid pressure P2 in the enclosing member of the beverage preparation device outside the capsule is in the range of 6-20 bar, preferably between 12 and 18 bar while the sealing structure is in the sealing contact with the annular end surface. 
     
     
         50 . The method according to  claim 47 , further comprising, prior to or at the start of brewing, exerting a force F1 on the sealing structure of the capsule using the annular end surface of said enclosing member to provide a sealing contact between the outwardly extending flange of the capsule and the enclosing member of the beverage preparation device, wherein F1 is in the range of 30-150 N preferably 40-150 N, more preferably 50-100 N, when the fluid pressure P1 in the enclosing member of the beverage preparation device outside the capsule is in the range of 0.1-4 bar, preferably 0.1-1 bar while the sealing structure is in the sealing contact with the annular end surface. 
     
     
         51 . The use method according to  claim 47 , further comprising, after the closing member of the beverage preparation device closes the enclosing member of the beverage preparation device, moving the enclosing member of the beverage preparation device moves relative to the closing member of the beverage preparation device under the effect of the pressure of the fluid in the enclosing member of the beverage preparation device towards the closing member of the beverage preparation device, to cause said annular end surface to apply the maximum clamping force onto the flange of the capsule. 
     
     
         52 . A method of manufacturing a capsule body of a capsule, for containing a substance for the preparation of a potable beverage by extracting and/or dissolving the substance by means of supplying a fluid under pressure into the capsule, capsule comprising:
 an aluminum capsule body having a central capsule body axis, said aluminum capsule body comprising a bottom, a side wall, an outwardly extending flange and a sealing structure at said flange; and   a cover sheet attached to said flange and hermetically closing off the capsule;   wherein said sealing structure is deformable for providing a fluid sealing contact with an annular end surface of an enclosing member of a beverage preparation device if the capsule is positioned in said enclosing member and said enclosing member is closed by means of a closing member of the beverage preparation device, such as an extraction plate of the beverage preparation device, at least portions of said flange and said sealing structure being clamped between said annular end surface and said closing member, said annular end surface optionally being provided with a plurality of radially extending open grooves;   characterized in that said sealing structure includes a deformable sealing ring portion of said flange, said sealing ring portion projecting axially from base portions of said flange, to which said cover is attached, on a side of said base portions opposite of said cover, said deformable sealing ring portion comprising:   an inner wall portion extending from and contiguous with an inner base portion of said flange;   an outer wall portion extending from and contiguous with an outer base portion of said flange, said outer wall being located radially outward of and radially spaced from said inner wall portion; and   a bridge portion interconnecting said inner wall portion and said outer wall portion, said bridge portion being located axially spaced from said base portions of said flange;   wherein, in radial cross-sectional view, a top of said bridge portion axially most remote from said base portions of the flange is flat or has a center plane curved with a radius of curvature larger than two times a wall thickness of said top of said bridge portion;   wherein at least a portion of the top of said bridge portion has a reduced wall thickness smaller than a wall thickness of said inner and outer wall portions;   further comprising a coating to at least one side of said capsule body, said coating being absent in at least said portion of the top of said bridge portion having a reduced wall thickness;   starting from a semi-finished deep drawn cup member, the method comprising reducing a wall thickness of a portion of said flange for forming said portion of said top of said bridge portion having a reduced wall thickness smaller than a wall thickness of said inner and outer wall portions, wherein said coating is removed from said portion of said flange of which the wall thickness is to be reduced prior to or during reducing the wall thickness.   
     
     
         53 . The method according to  claim 52 , wherein said coating is removed from said portion of said flange of which the wall thickness is to be reduced during a material removal step for removing wall material for reducing said wall thickness.