Core axle with adjustable retainer

Claim 2

An expandable mandrel for internally gripping a hollow member having a cylindrical bore and for supporting such member for rotation about a selected axis, comprising, in combination: an elongate body presenting an outer surface dimensioned to be loosely received in the cylindrical bore of said hollow member and having opposite end faces, said body having an outwardly facing channel extending longitudinally at least through a major portion of the length of said body to present parallel side walls and a bottom wall, said body having a pair of longitudinally spaced blind bores extending inwardly from said bottom wall of the channel parallel to said side walls, each of said blind bores being of predetermined depth; an elongate gripper bar slidably fitted between said side walls within said channel, said bar being of a length less than that of said channel and adapted normally to reside in bottomed relation in said channel with the opposite ends of the bar spaced inwardly with respect to the corresponding opposite end faces of the body, said bar having a pair of notches therein facing said bottom wall of the channel and defining cam surfaces sloping upwardly from said bottom wall of the channel in directions away from one end face of the body and registered respectively with said blind bores when said bar is in such normal position, said bar being of a height to allow said mandrel to be received in said bore of the hollow member when the bar is in said normal position thereof; a pair of cylindrical pins rotatably seated in said blind bores, each pin having a bevelled end portion projecting outwardly from the bottom wall of the channel and presenting sloping end faces in face-to-face contact with respective ones of said cam surfaces on the bar; and actuating means at said one end face of the body in radially offset position with respect to said selected axis for axially shifting said bar within said channel while allowing the bar to ride outwardly into engagement with the hollow member due to reaction of said cam surfaces against said end faces of the pins.

Claim 3

An expandable mandrel as defined in claim 1 including means for limiting the radial displacement of said gripper bar.

Claim 4

An expandable mandrel as defined in claim 1 including means for limiting the radial displacement of said bar, said means comprising a retaining member having a shank engaging in the bottom wall of said channel and an enlarged head spaced above said bottom wall but within the confines of said channel, said bar having an elongate slot receiving said shank and an enlarged recess surmounting said slot receiving said enlarged head.

Claim 5

An expandable mandrel as defined in claim 3 wherein said channel terminates short of said one end face of the body to dEfine a portion presenting an end wall for the channel, said portion having a threaded bore, and said actuating means comprising a threaded member engaged in said threaded bore to bear against said bar.

Claim 6

An expandable mandrel as defined in claim 1 wherein each blind bore is of a diameter at least equal to the width of said channel whereby each pin presents an end face extending at least the full width of the channel.

Claim 7

An expandable mandrel as defined in claim 2 wherein the sloping end face of each pin lies in full outwardly from the bottom wall of the channel so that each pin fully fills its associated blind bore.

Claim 8

An expandable mandrel as defined in claim 1 wherein said channel terminates short of said one end face of the body to define a portion presenting an end wall for the channel, said portion having a threaded bore, and said actuating means comprising a threaded member engaged in said threaded bore to bear against said bar.

Claim 9

An expandable mandrel for internally gripping a hollow member having a cylindrical bore and for supporting such member for rotation about a selected axis, comprising, in combination: an elongate body presenting a cylindrical outer surface and opposite end faces and having a radially outwardly facing channel extending longitudinally from a point adjacent one end face through the opposite end face of the body to present parallel side walls, a bottom wall and an end wall, said body having a radially offset threaded bore extending longitudinally of said body in alignment with said channel through said one end face and said end wall of the channel and having a pair of longitudinally spaced blind bores extending radially inwardly from said bottom wall of the channel, each of said blind bores being of predetermined depth; an elongate, rectangular gripper bar slidably fitted within said channel, said bar being of a length less than that of said channel and adapted normally to reside in seated relation in said channel with one end of the bar in close proximity to said end wall of the channel, said bar having a pair of notches therein defining cam surfaces sloping upwardly from said bottom wall of the channel in directions away from said end wall thereof and registered respectively with said blind bores when said bar is in such normal position, said bar being of a height substantially the same as the depth of said channel; a pair of cylindrical pins rotatably seated in said blind bores, each pin having a bevelled end portion projecting outwardly from the bottom wall of the channel and presenting sloping end faces in face-to-face contact with respective ones of said cam surfaces on the bar; a threaded adjusting member engaged in said threaded bore and bearing against said one end of the bar whereby axially to shift said bar within said channel to allow corresponding radial outward displacement thereof due to reaction of said cam surfaces against said end faces of the pins; and means for limiting the radial displacement of said bar, said means comprising a retaining member having a shank engaging in the bottom wall of said channel and an enlarged head spaced above said bottom wall but within the confines of said channel, said bar having an elongate slot receiving said shanks and an enlarged recess surmounting said slot receiving said enlarged head.

Claim 10

An expandable mandrel for internally gripping a hollow member having a cylindrical bore and for supporting such member for rotation about a selected axis, comprising, in combination: an elongate body presenting a cylindrical outer surface and opposite end faces and having a radially outwardly facing channel extending longitudinally from a point adjacent one end face through the opposite end face of the body to present parallel side walls, a bottom wall and an end wall, said body having a radially offset threaded bore extending longitudinally of said body in alignment with said channel through said one end face and said end wall of the channel and having a pair of longitudinally spaced blind bores extending radially inwardly from said bottom wall of the channel, each of said blind bores being of predetermined depth; an elongate, rectangular gripper bar slidably fitted within said channel, said bar being of a length less than that of said channel and adapted normally to reside in seated relation in said channel with one end of the bar in close proximity to said end wall of the channel, said bar having a pair of notches therein defining cam surfaces sloping upwardly from said bottom wall of the channel in directions away from said end wall thereof and registered respectively with said blind bores when said bar is in such normal position, said bar being of a height substantially the same as the depth of said channel; a pair of cylindrical pins rotatably seated in said blind bores, each pin having a bevelled end portion projecting outwardly from the bottom wall of the channel and presenting sloping end faces in face-to-face contact with respective ones of said cam surfaces on the bar; a threaded adjusting member engaged in said threaded bore and bearing against said one end of the bar whereby axially to shift said bar within said channel to allow corresponding radial outward displacement thereof due to reaction of said cam surfaces against said end faces of the pins; and means for limiting the radial displacement of said bar, said means comprising a retaining member having a shank engaging in the bottom wall of said channel and an enlarged head spaced above said bottom wall but within the confines of said channel, said bar having an elongate slot receiving said shanks and an enlarged recess surmounting said slot receiving said enlarged head.

Claim 11

An expandable mandrel as defined in claim 8 wherein each blind bore is of a diameter at least equal to the width of said channel whereby each pin presents an end face extending at least the full width of the channel.

Claim 12

An expandable mandrel as defined in claim 9 wherein the sloping end face of each pin lies in full outwardly from the bottom wall of the channel so that each pin fully fills its associated blind bore.