Abstract An adjustable boring bar characterized in that the bar has a transverse rectangular slot diametrically therethrough in which the overlapped rectangular shank portions of a pair of cutter elements are slidable for simultaneous radial outward or inward movement with respect to the longitudinal axis of the bar by a screw actuated cam means which engages the respective shank portions. The screw actuated cam means comprises a nut movable in a transverse bore in the bar by rotation of a dial screw, said nut having an inclined cam face which engages the tapered rear end of a cam plunger to move it longitudinally in a central bore in the bar, said plunger having a V-shaped front end engaged with offset V-shaped notches in the respective shank portions of the cutter elements. The adjustable boring bar herein is further characterized in that the cutter elements are locked in adjusted position by screw means in the bar extending transversely through openings in the overlapped shank portions of the cutter elements and being operative to constrict the transverse slot to firmly clamp the overlapped shank portions together.
An adjustable boring bar comprising a bar having a longitudinal bore intersected by a transverse slot of rectangular cross-section and by a transverse bore; a pair of cutter elements having rectangular shank portions slidable in said slot and having cutting edges at their radially outer extremities; screw actuated cam means in said transverse bore; a cam plunger movable lengthwise in said longitudinal bore and having engagement with said cam means and with said cutter elements to move the latter in said transverse slot responsive to actuation of said cam means; clamp screw means in said bar operative to flex the slotted portion of said bar to firmly clamp said shank portions together in predetermined adjusted relation; said transverse slot comprising a groove in the end portion of said bar which defines the opposite side walls and one end wall of said slot; a cap member secured on the end of said bar to close said groove to form the other end wall of said slot; and screw means eccentrically disposed with respect to said clamp screw means for securing said cap member to said bar whereby tightening of said clamp screw means flexes the opposite side walls of said slot toward each other into clamping relation with the overlapped shank portions of said cutter elements therebetween.
Claim 2
Dependent Claim
216 words
An adjustable boring bar comprising a bar having a longitudinal bore intersected by a transverse slot of rectangular cross-section and by a transverse bore; a pair of cutter elements having rectangular shank portions slidable in said slot and having cutting edges at their radially outer extremities; screw actuated cam means in said transverse bore; a cam plunger movable lengthwise in said longitudinal bore and having engagement with said cam means and with said cutter elements to move the latter in said transverse slot responsive to actuation of said cam means; clamp screw means in said bar operative to flex the slotted portion of said bar to firmly clamp said shank portions together in predetermined adjusted relation; said transverse slot comprising a groove in the end portion of said bar which defines the opposite side walls and one end wall of said slot; a cap member secured on the end of said bar to close said groove to form the other end wall of said slot; and screw means eccentrically disposed with respect to said clamp screw means for securing said cap member to said bar whereby tightening of said clamp screw means flexes the opposite side walls of said slot toward each other into clamping relation with the overlapped shank portions of said cutter elements therebetween.
Claim 3
Dependent Claim
56 words
The adjustable boring bar of claim 1 wherein said screw means for securing said cap member to said bar are at two diagonally opposite corners of said cap memBer while the other two diagonally opposite corners are unrestrained for flexing by said clamp screw means which extends in eccentric relation to said diagonally opposite screw means.
Claim 4
Dependent Claim
46 words
The adjustable boring bar of claim 1 wherein said cap member is bottomed in a groove diametrically across the end of said boring bar, said groove being perpendicular to said slot and having its bottom substantially flush with the adjacent sides of said overlapping shank portions.