# US 11,077,501 B2 · Method of machining a rotationally symmetric surface of a workpiece and turning apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,077,501 B2 - Document ID: US11077501B2 - Status: Granted - Kind: B2 - Application number: 16/316,427 - Filed: 2016-09-09 - Published: 2019-08-01 - Granted: 2021-08-03 - Earliest claimed: 2016-09-09 - Assignees: Sumitomo Electric Hardmetal Corp. - Applicants: Sumitomo Electric Hardmetal Corp. - Inventors: Makoto Abe; Christoph Zeiner - Web page: https://patentgrep.com/patent/US11077501B2 ## CPC - B23B 1/00: Methods for turning or working essentially requiring the use of turning-machines; Use of auxiliary equipment in connection with such methods - B23B 27/005: {Geometry of the chip-forming or the clearance planes, e.g. tool angles (B23B27/141 and B23B27/22 take precedence)} - B23B 27/141: {Specially shaped plate-like cutting inserts, i.e. length greater or equal to width, width greater than or equal to thickness (with specially shaped plate-like exchangeable cutting inserts, e.g. chip-breaking groove, B23B27/1603; with removable plate-like milling cutting inserts of special shape B23C5/202)} - B23B 27/148: {Composition of the cutting inserts} - B23Q 7/00: Arrangements for handling work specially combined with or arranged in, or specially adapted for use in connection with, machine tools, e.g. for conveying, loading, positioning, discharging, sorting (incorporated in working-spindles B23B13/00) - B23B 2200/28: Angles - B23B 2250/12: Cooling and lubrication - B23B: TURNING; BORING (arrangements for copying or controlling B23Q) - B23Q: DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING (tools of the kind used in lathes or boring machines B23B27/00); MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT ## Abstract In accordance with various illustrative embodiments of the present disclosure, a rotationally symmetric surface of a workpiece is machined by a turning apparatus, wherein the workpiece is rotationally driven around a rotational axis, a cutting tool with a cutting edge positioned at the edge of a rake face is arranged relative to the workpiece, the cutting tool is brought into contact with the workpiece, and the cutting tool is advanced relative to the workpiece along a feed direction parallel to the rotational axis, the normal to the rake face being tilted relative to the feed direction, a first axis and a second axis, the first axis and the second axis are perpendicular to the feed direction and perpendicular to each other. ## Claims ### Claim 1 A method of machining a rotationally symmetric surface of a workpiece, said method comprising: rotationally driving said workpiece around a rotational axis, arranging a cutting tool with a cutting edge positioned at an edge of a rake face relative to said workpiece, bringing said cutting tool into contact with said workpiece, and advancing said cutting tool relative to said workpiece along a feed direction parallel to said rotational axis, wherein a normal to said rake face is tilted relative to said feed direction, a first axis and a second axis, the first axis and the second axis being perpendicular to the feed direction and perpendicular to each other, wherein a direction of said normal of said rake face is set to a direction (i) rotated around said first axis by an angle α from a start direction identical to a direction of said second axis, such that said normal from said rake face is directed to said feed direction and (ii) rotated around a third axis by an angle δ such that said normal from said rake face is directed to said feed direction, and said third axis corresponds to an axis which originally corresponds to said rotational axis and is rotated around said first axis by said angle α, wherein said angle α is in a range from 35° to 60°, wherein said angle δ is in a range from 0° to 15°, and wherein a feed rate of said cutting tool is in a range from 0.2 mm per revolution to 1.2 mm per revolution. ### Claim 2 (depends on 1) The method of claim 1, wherein said cutting edge has the shape of a straight line. ### Claim 3 (depends on 1) The method of claim 1, wherein said cutting edge has the shape of a curved line. ### Claim 4 (depends on 3) The method of claim 3, wherein said cutting edge is curved away from said workpiece towards at least one end of said cutting edge. ### Claim 5 (depends on 3) The method of claim 3, wherein a diameter of said workpiece is determined at said rotationally symmetric surface of said workpiece, and wherein said curved line corresponds to a circular arc of a circle having a radius, said radius being greater than one quarter of said diameter. ### Claim 6 (depends on 1) The method of claim 1, wherein said rotationally symmetric surface of said workpiece is an outer circumferential surface of said workpiece. ### Claim 7 (depends on 1) The method of claim 1, wherein said rotationally symmetric surface of said workpiece is an inner circumferential surface of said workpiece. ### Claim 8 (depends on 7) The method of claim 7, wherein said cutting edge has the shape of a curved line, wherein a diameter of said workpiece is determined at said rotationally symmetric surface of said workpiece, and wherein said curved line corresponds to a circular arc of a circle having a radius, said radius being greater than one quarter of said diameter and said radius being smaller than one half of said diameter. ### Claim 9 (depends on 1) The method of claim 1, wherein upon engaging said workpiece, said cutting edge contacts said workpiece along an active cutting portion of said cutting edge, an effective length of said active cutting portion being smaller than a total length of said cutting edge.