Method for Making a Filter Segment for a Disc Filter and the Filter Segment

Abstract

A disc filter disposed around a drum for filtering water. The disc filter includes a frame structure and a plurality of filter segments arranged around the drum and secured to the support. Each filter segment includes a filter frame having first and second portions and filter material integrated with the first and second portions of the filter frame through an injection moulding process.

1 - 11 . (canceled) 
     
     
         12 . A method for making a disc-shaped filer segment for a disc filter, said filter segment comprising a filter frame and a filter material, said filter frame being adapted for a filter support of the disc filter, characterised by an injection moulding of the filter frame in a lower half and upper half, wherein said filter material is stretched and during injection moulding in stretched condition is integrated in the lower half and the upper half of the filter frame, and wherein the filter material after injection moulding exhibits a residual stretching of the material. 
     
     
         13 . A method as claimed in  claim 12 , characterised in that the lower half of the filter frame is injection moulded in a first step, that the filter material is thereafter placed against the lower half and stretched, and that the upper half of the filter frame is injection moulded in a second step, wherein the filter material in the second step is integrated in the lower half and the upper half of the filter frame. 
     
     
         14 . A method as claimed in  claim 12 , characterised in that the residual stretching is more than 2 N/cm. 
     
     
         15 . A method as claimed in  claim 12 , characterised in that the filter frame exhibits a generally elongated shape, wherein at least one reinforcement beam extends between the long sides of the filter frame. 
     
     
         16 . A method as claimed in  claim 15 , characterised in that the reinforcement beam by injection moulding is integrated in the filter cloth. 
     
     
         17 . A filter segment for a disc filter, including a filter frame and a filter material, said filter frame being adapted for a filter support of the disc filter, characterised by an injection moulded filter frame with a filter material integrated in stretched condition between a lower half of the filter frame and an upper half of the filter frame, said filter material after injection moulding exhibiting a residual stretching of the material. 
     
     
         18 . A filter segment as claimed in  claim 17 , characterised in that the residual stretching is more than 2 N/cm. 
     
     
         19 . A filter segment as claimed in  claim 17 , characterised in that the filter frame exhibits a generally elongated shape, wherein at least one reinforcement beam extends between the long sides of the filter frame. 
     
     
         20 . A filter segment as claimed in  claim 17 , characterised in that the reinforcement beam by injection moulding is integrated in the filter cloth. 
     
     
         21 . A filter segment as claimed in  claim 17 , characterised in that the filter frame consists of glass fibre reinforced polypropylene. 
     
     
         22 . A filter segment as claimed in  claim 17 , characterised in that the filter material includes polyester. 
     
     
         23 . A method for making a filter segment for a disc filter, comprising:
 injection moulding filter material into a filter frame to form an integrated filter frame and filter material by:
 i. injection moulding a first portion of the filter frame in a first injection moulding process; 
 ii. stretching the filter material over the first portion of the filter frame produced in the first injection moulding process; and 
 iii. subjecting the first portion of the filter frame and the stretched filter material to a second injection moulding process where the second injection moulding process:
 (1) forms a second portion of the filter frame; and (2) integrates the filter material into the first and second portions of the filter frame. 
 
   
     
     
         24 . The method of  claim 23  wherein after the second injection moulding process, the filter material exhibits a residual stretching of the material. 
     
     
         25 . The method of  claim 24  wherein the residual stretching is more than 2 N/cm. 
     
     
         26 . The method of  claim 23  wherein the filter frame includes an outer parameter that extends around the filter material and wherein the method further provides a transverse beam that extends across opposite portions of the outer perimeter and wherein the second injection moulding process integrates the filter material with the transverse beam. 
     
     
         27 . The method of  claim 23  wherein the filter frame includes first and second half sections and wherein the second injection moulding process sandwiches the filter material between the first and second half sections of the filter frame. 
     
     
         28 . The method of  claim 23  wherein the filter frame is constructed of plastic material and the method includes penetrating the filter material with the plastic material of the filter frame and fixing the filter material to the filter frame. 
     
     
         29 . A water filtering apparatus, comprising:
 a drum;   a disc filter secured around the drum for filtering water;   the disc filter including a support structure;   a plurality of filter segments arranged around the drum and supported by the filter support; and   each filter segment including a filter frame comprising first and second sections and a filter material integrated into the first and second sections of the filter frame.   
     
     
         30 . The water filtering apparatus of  claim 29  wherein the filter frame includes a perimeter frame that is split into first and second half sections. 
     
     
         31 . The water filtering apparatus of  claim 29  wherein the filter frame is constructed of plastic material and wherein the plastic material of the filter frame penetrates the filter material and fixes the filter material to the filter frame. 
     
     
         32 . The water filtering apparatus of  claim 31  wherein the plastic filter frame includes a perimeter portion and a transverse beam extending between portions of the perimeter portion of the filter frame and wherein the plastic material of the transverse beam penetrates the filter material and fixes the filter material to the transverse beam. 
     
     
         33 . The water filtering apparatus of  claim 28  wherein the filter frame comprises glass fiber reinforced polypropylene and wherein portions of the glass fiber reinforced polypropylene penetrates the filter material and fixes the filter material to the glass fiber reinforced polypropylene.