Filtration base for vacuum diaphragm filtration

Abstract

A filtration base for vacuum membrane filtration applications comprises a membrane bearing area on the upper side of the filtration base, which has a bearing structure and a supporting contour surrounding the bearing structure for a membrane filter placed in the membrane bearing area. The supporting contour has at least one notch which is in flow connection with the bottom side of the membrane bearing area and which is arranged such that it is adapted to be selectively covered by a membrane filter placed in the membrane bearing area.

1 . A filtration base for vacuum membrane filtration applications, comprising a membrane bearing area on an upper side of the filtration base, which has a bearing structure and a supporting contour surrounding the bearing structure for a membrane filter placed in the membrane bearing area,
 characterized in that the supporting contour has at least one notch which is in flow connection with the bottom side of the membrane bearing area and which is arranged such that it is adapted to be selectively covered by a membrane filter placed in the membrane bearing area.   
     
     
         2 . The filtration base according to  claim 1 , characterized in that the notch interrupts a circumferential edge between the bearing structure and the supporting contour. 
     
     
         3 . The filtration base according to  claim 2 , characterized in that the notch is delimited in a sharp-edged manner. 
     
     
         4 . The filtration base according to  claim 3 , characterized in that the notch extends into the supporting contour. 
     
     
         5 . The filtration base according to  claim 1 , characterized in that the supporting contour on its outside adjoins a sealing face onto which the rim of the membrane filter can be pressed by a pouring funnel put onto the filtration base. 
     
     
         6 . The filtration base according to  claim 5 , characterized in that the notch does not extend into the sealing face. 
     
     
         7 . The filtration base according to  claim 5 , characterized in that the bearing structure and the sealing face are arranged offset to each other and in that a difference in height between the bearing structure and the sealing face is bridged by the supporting contour. 
     
     
         8 . The filtration base according to  claim 1 , characterized in that the membrane bearing area has an outer diameter in the range of 15 to 55 mm and in that the at least one notch is formed at a distance in the range of 2 to 10 mm from the outer diameter. 
     
     
         9 . The filtration base according to  claim 1 , characterized in that the supporting contour is annular and in that a plurality of notches spaced apart from each other in the circumferential direction is provided. 
     
     
         10 . The filtration base according to  claim 9 , characterized in that each angular distance between the notches is of equal size. 
     
     
         11 . The filtration base according to  claim 9  or  10 , characterized in that the notches have a width in the range of 0.1 to 4 mm in the circumferential direction. 
     
     
         12 . The filtration base according to  claim 9 , characterized in that the notches have a depth in the range of 0.1 to 1.5 mm. 
     
     
         13 . The filtration base according to  claim 1 , characterized in that the at least one notch is a prolongation of a discharge groove formed in the bearing structure. 
     
     
         14 . The filtration base according to  claim 1 , characterized in that the filtration base is made of a sterilizable plastic material. 
     
     
         15 . A filtration device comprising a filtration base according to  claim 1  a pouring funnel detachably mounted on the filtration base, and a membrane filter clamped between the filtration base and the pouring funnel. 
     
     
         16 . The filtration device according to  claim 15 , characterized in that the membrane filter is clamped between a sealing face surrounding the supporting contour and a bulge of the funnel. 
     
     
         17 . The filtration device according to  claim 15 , characterized in that the filtration base is connected to a suction device. 
     
     
         18 . The filtration device according to  claim 17 , characterized in that the at least one notch is dimensioned so small that in case of a negative pressure generated by the suction device for a filtration process, the membrane filter does not come into tight contact with the contour of the notch due to its stiffness. 
     
     
         19 . The filtration device according to any of  claims 15  to  18 , characterized in that the filtration base and/or the funnel and/or the suction device are made of a sterilizable plastic material.