Apparatus and method for forming a screw flight

Abstract

This invention relates to an apparatus for forming a helical screw flight from a flight blank. The apparatus includes a base and an engaging means. The engaging means is movably mounted to the base and is configured to formingly engage the blank so as to form a twist in at least a portion of the flight blank corresponding to a predetermined pitch of the flight.

1 .- 16 . (canceled) 
     
     
         17 . A method of setting up an apparatus for forming a helical screw flight from a flight blank, the apparatus being of the type having a first mounting frame and a second mounting frame movable relative to each other, wherein the method includes the steps of:
 mounting a first central forming plate to the first mounting frame such that a first central forming edge of the first central forming plate is spaced from the first central forming plate by a first predetermined distance;   mounting a first left side plate to the first mounting frame such that a first left forming edge of the first left side plate extends at an angle relative to the first central forming edge; and   positioning the first left side plate such that a portion of the first left forming edge is also spaced from the first central forming plate by the first predetermined distance.   
     
     
         18 . The method according to  claim 17 , including the step of:
 positioning the first left side plate such that a centre point of the first left forming edge is spaced from the first central forming plate by the first predetermined distance.   
     
     
         19 . The method according to  claim 17 , including the step of:
 positioning the first left side plate such that the portion of the first left forming edge is arranged at a predetermined base or lateral offset distance from the first central forming edge.   
     
     
         20 . The method according to  claim 17 , including the step of:
 positioning the first left side plate such that the portion of the first left forming edge is arranged at a predetermined distance along a first left receiving formation of the first mounting frame relative to an apex formed between axis of the first central forming edge and the first left receiving formation.   
     
     
         21 . The method according to  claim 17 , including the step of:
 mounting a first right side plate to the first mounting frame such that a first right forming edge of the first right side plate extends at an angle relative to the first central forming edge, wherein the line along which the first left forming edge and the first right forming edge meet at an apex; and   positioning the first right side plate such that a portion of the first right forming edge is also spaced from the first central forming plate by the first predetermined distance.   
     
     
         22 . The method according to  claim 17 , including the step of:
 mounting a second central forming plate to the second mounting frame such that a second central forming edge of the second central forming plate is spaced from the second central forming plate by a second predetermined distance;   mounting a second left side plate to the second mounting frame such that a second left forming edge of the second left side plate extends at an angle relative to the second central forming edge; and   positioning the second left side plate such that a portion of the second left forming edge is also spaced from the second central forming plate by the second predetermined distance.   
     
     
         23 . The method according to  claim 22 , including the step of:
 positioning the second left side plate such that a centre point of the second left forming edge is spaced from the second central forming plate by the second predetermined distance.   
     
     
         24 . The method according to  claim 22 , including the step of:
 positioning the second left side plate such that the portion of the second left forming edge is arranged at a predetermined base or lateral offset distance from the second central forming edge.   
     
     
         25 . The method according to  claim 22 , including the step of:
 positioning the second left side plate such that the portion of the second left forming edge is arranged at a predetermined distance along a second left receiving formation of the second mounting frame relative to an apex formed between axis of the second central forming edge and the second left receiving formation.   
     
     
         26 . The method according to  claim 22 , including the step of:
 mounting a second right side plate to the second mounting frame such that a second right forming edge of the second right side plate extends at an angle relative to the second central forming edge, wherein the line along which the second left forming edge and the second right forming edge meet at an apex; and   positioning the second right side plate such that a portion of the second right forming edge is also spaced from the second central forming plate by the second predetermined distance.   
     
     
         27 . The method according to  claim 17 , including the step of:
 providing a set up device with at least one rule;   positioning the set up device relative to the first mounting frame, thereby to facilitate the positioning of the first left side plate such that the first left forming edge is arranged in the desired position relative to the first central forming edge.   
     
     
         28 . The method according to  claim 27 , wherein the set up device includes a mounting bracket and a pair of oppositely directed rulers extending laterally from the mounting bracket, and the method further includes the steps of;
 securing the set up device via the mounting bracket to the first central forming plate such that the first left forming edge can be moved into engagement with the respective rule so as to position first left side plate relative to the first mounting frame.