A method for hard finishing two different toothings on a workpiece, wherein, prior to each machining process, to set the correct tool engagement position for the machining process, a first relative rotational angle position of a first rotational position reference of the first toothing is determined relative to an axial rotational position of the workpiece spindle holding and clamping the workpiece for the first machining, and a second relative rotational angle position of a second rotational position reference of the second toothing is determined relative to an axial rotational position of a workpiece spindle holding and clamping the workpiece for the second machining, wherein the machining operations are carried out on the same workpiece spindle with no intervening clamping change, and with the first and second rotational position references coupled to each other as the basis thereof.

A method for grinding a gear wheel by a worm grinding wheel in a grinding machine, wherein the tooth flanks of the gear wheel are ground by the abrasive flanks of the profiling of the worm grinding wheel. In order to increase the productivity of the grinding, the method includes the following steps: a) calculating the engagement ratios between the abrasive flanks of the profiling of the worm grinding wheel and the tooth flanks of the gear wheel, wherein the size of the profile forming zone is determined; b) determining a geometry modified in respect of the geometry determined according to step a) such that the profile forming zone is minimal; c) profiling the worm grinding wheel with the geometry which has thus resulted; d) grinding the gear wheel by the worm grinding wheel profiled according to step c).

A method for the manufacture of a gear component includes, in a soft machining process, introducing a preliminary toothing 3 with a machining allowance 7 that is fixed relative to a final toothing 4 into a blank such that a semi-finished part 2 is produced. The method also includes, in a fine machining process, removing the machining allowance 7 and producing the final toothing 4 of the toothed component. The machining allowance 7 is removed in a single-stage hobbing method by a grinding tool 1, wherein the grinding tool 1 removes the machining allowance completely in a single stroke movement H.

A lay shaft assembly for a speed reduction gearbox in a geared turbofan gas turbine engine, the lay shaft assembly having an output gear formed on a lay shaft as a single piece, and an input welded gear formed as a separate piece that is welded to the shaft in close proximity to the output gear. The output gear is machined and precision-ground prior to welding the input welded gear to the lay shaft so that the two gears can be located in close proximity. The input welded gear is precision-ground after the gear has been welded to the shaft.

A lay shaft assembly for a speed reduction gearbox in a geared turbofan gas turbine engine, the lay shaft assembly having an output gear formed on a lay shaft as a single piece, and an input welded gear formed as a separate piece that is welded to the shaft in close proximity to the output gear. The output gear is machined and precision-ground prior to welding the input welded gear to the lay shaft so that the two gears can be located in close proximity. The input welded gear is precision-ground after the gear has been welded to the shaft.

Method for cutting a gear (4) from a metal workpiece (2), in which a tooth flank, still having an oversize compared with its predefined final geometry, of the gear is, in one or more cutting passes in cutting engagement with one or more cutting tools (10) fed thereto, hard-fine finished with a geometrically undefined cutting edge made of cutting grains incorporated in a binder matrix, in order to produce a reflective property, existing in the final geometry, of its surface, wherein, in a cutting pass of a cutting tool (10b), both an elastically resilient mounting of the cutting grains set by its binder matrix acts on this surface property, and a cutting reduction of the oversize by at least 2 μm at the tooth flank is realized by a compressive preload, set via the infeed of the cutting tool, to which the cutting engagement is subjected; as well as a gear-cutting tool and a machine tool for this purpose.

A method wherein a cutting or grinding chamfering tool (25) is guided along the face width of a gear (12, 23, 52) through one tooth slot (8) (e.g. from heel to toe) while it contacts the topland corners (10, 1 1) of the respective concave and convex tooth flanks of adjacent teeth (2, 4). The tool moves to an index position, the gear is indexed to the next tooth slot position and the tool moves through the tooth slot (e.g. from the toe to the heel). The cycle is repeated until all topland corners are chamfered.

A method wherein a cutting or grinding chamfering tool (25) is guided along the face width of a gear (12, 23, 52) through one tooth slot (8) (e.g. from heel to toe) while it contacts the topland corners (10, 1 1) of the respective concave and convex tooth flanks of adjacent teeth (2, 4). The tool moves to an index position, the gear is indexed to the next tooth slot position and the tool moves through the tooth slot (e.g. from the toe to the heel). The cycle is repeated until all topland corners are chamfered.

A mutual-lapping device and mutual-lapping method for improving processing precision based on the principle of error averaging is proposed. The device including driving friction wheel, driving belt pulley, transmission belt A, connecting rod A, rotation shaft segment A, multi-ball sleeve, mutual-lapping gear A, tension spring, driven friction wheel, pendulum bar of the driven friction wheel, driven belt pulley, transmission belt B, connecting rod B, pressure spring of tensioning pulley, tensioner mechanism, rotation shaft segment B and mutual-lapping gear B. By mutual lapping the high-precision gears, not only the pitch deviation, tooth profile deviation, helix deviation and runout can be reduced synchronously, but also the machining cost is low. Meanwhile, the effect of improving pitch accuracy, profile accuracy, helix accuracy and runout accuracy and reducing surface roughness is remarkable.

A mutual-lapping device and mutual-lapping method for improving processing precision based on the principle of error averaging is proposed. The device including driving friction wheel, driving belt pulley, transmission belt A, connecting rod A, rotation shaft segment A, multi-ball sleeve, mutual-lapping gear A, tension spring, driven friction wheel, pendulum bar of the driven friction wheel, driven belt pulley, transmission belt B, connecting rod B, pressure spring of tensioning pulley, tensioner mechanism, rotation shaft segment B and mutual-lapping gear B. By mutual lapping the high-precision gears, not only the pitch deviation, tooth profile deviation, helix deviation and runout can be reduced synchronously, but also the machining cost is low. Meanwhile, the effect of improving pitch accuracy, profile accuracy, helix accuracy and runout accuracy and reducing surface roughness is remarkable.