Patent ID: 7908728
Filing Date: 2011-03-22
Classification: B23P,B25B,B29C,Y10T

Abstract:
1. A puller assembly for removing at least one screw element from a screw shaft of a screw-type extrusion machine, the at least one screw element including a sleeve portion received annularly about the screw shaft and at least one flute extending radially outward from the sleeve portion, said puller assembly comprising: a body haying a sleeve portion with an inner diameter sufficiently sized for axially fitting over the at least one screw element on the screw shaft; at least one engaging element removably secured to said body for enabling said body to be axially installed on the at least one screw element when said at least one engaging element is removed from said body and axially locking said body on the at least one screw element when said at least one engaging element is installed in said body, said at least one engaging element extending radially inward relative to said inner diameter of said sleeve portion beyond an outer radial edge of the at least one flute when said at least one engaging elements is installed in said body to axially lock said body to the at least one screw element; and a pulling device for selectively applying an axial pulling force to said body to axially move said at least one screw element along said screw shaft, said at least one engaging element engaging said at least one flute to thereby axially force said at least one engaging element to move along said shaft, wherein said pulling device includes: an extension shaft removably secured to one end of said screw shaft; a puller shaft tailpiece annularly disposed on said extension shaft and axially spaced apart from said body; at least one connector element connected to each of said body and said puller shaft tailpiece; and a drive assembly that, upon actuation, moves said puller shaft tailpiece axially along said extension shaft and through said at least one connector element axially moves said body to move said at least one screw element along said screw shaft.