GB546973A - Improvements in finishing and like cutting tools - Google Patents

Abstract

546,973. Reamers etc.; taps. OSWIN, J. Jan. 30, 1941, No. 1203. [Class 83 (iii)] [Also in Group XXIII] A finishing or like cutting tool such as a reamer, tap, hone or lap &c. has the periphery eccentrically reduced at or near the leading end, such as from the line 13, Fig. 1, to facilitate its entry. The reduction may be by champfering, bevelling, radiusing &c. or the tool periphery may be shaped as described in Specifications 520,065 or 525,358, [both in Group XIX]. The parts of the leading edge having full dimensions may be tipped with hard alloy. In a modification the leading end of a hone is eccentrically reduced at 17, Fig. 3, and the tool also has a pilot portion 18 formed as described in Specifications 520,065 or 524,866. In a further modification the tool is concentrically bevelled at 20, Fig. 5, and has a part annular groove 21 constituting the eccentric reduction near the leading end. In another modification the tool is concentrically bevelled at 20, Fig. 7, and in addition the end is eccentrically reduced below the line 13. The invention is also applicable to hollow tools cutting on their inner edges which are then eccentrically enlarged instead of being reduced.