A method for automatic process monitoring during continuous generating grinding of pre-toothed workpieces, which permit early detection of grinding wheel breakouts. A generating grinding machine is used to machine multiple workpieces by clamping them onto at least one workpiece spindle and successively moving them into generating engagement with a grinding wheel. At least one measured variable is monitored during the machining to indicate if a grinding wheel breakout exists. If a grinding wheel breakout is indicated, the grinding wheel is examined automatically by moving a dressing tool over the tip region of the grinding wheel and generating a contact signal. A breakout is determined by analyzing the contact signal and, if present, the grinding wheel is dressed as often as necessary in order to eliminate the grinding wheel breakout. Alternatively, the checking of the grinding wheel is carried out directly at the first dressing stroke.

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.

Method for hard machining of a precut and heat-treated gearwheel workpiece using a tool in a gear processing machine, having sensors and/or detectors, comprising: providing target data of the workpiece, determining a first relative movement of the tool relative to the workpiece based on the target data, executing the first relative movement, wherein an NC-controller brings the tool into contact with the workpiece in a controlled manner by the execution of the first relative movement, providing real-time measured values and movement data by means of the sensors and/or detectors during the execution of the first relative movement, performing an analysis of the real-time measured values together with the movement data and determining adapted, workpiece-specific relative movements, hard machining at least one region of a tooth of the workpiece, wherein the NC-controller executes the adapted, workpiece-specific relative movements of the tool relative to the workpiece.

Method for hard machining of a precut and heat-treated gearwheel workpiece using a tool in a gear processing machine, having sensors and/or detectors, comprising: providing target data of the workpiece, determining a first relative movement of the tool relative to the workpiece based on the target data, executing the first relative movement, wherein an NC-controller brings the tool into contact with the workpiece in a controlled manner by the execution of the first relative movement, providing real-time measured values and movement data by means of the sensors and/or detectors during the execution of the first relative movement, performing an analysis of the real-time measured values together with the movement data and determining adapted, workpiece-specific relative movements, hard machining at least one region of a tooth of the workpiece, wherein the NC-controller executes the adapted, workpiece-specific relative movements of the tool relative to the workpiece.

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 first workpiece (2, 40) is loaded to a spindle (30) of a workpiece processing machine with the first toothed workpiece having a predetermined design and being in a predetermined rotational load position. The first toothed workpiece is stock-divided and a machining position is determined based on the stock-dividing. The first toothed workpiece is rotationally adjusted to the machining position. The teeth (3, 42) of the first toothed workpiece are then machined and the first workpiece is removed from the spindle. A second toothed workpiece is loaded to the spindle of the workpiece processing machine. The second toothed workpiece has the same predetermined design and is in the same predetermined rotational load position as the first toothed workpiece. The second toothed workpiece is rotationally adjusted from the predetermined rotational load position to the machining position by the same adjustment amount as the first toothed workpiece. The second toothed workpiece is machined and then removed from the machine spindle. The process as performed for the second toothed workpiece can be repeated for subsequent workpieces having the same design and being in the same rotational load position as the first and second workpieces. For the second and subsequent toothed workpieces, the step of determining the rotary position of the teeth is not carried out.

For the precision machining of a workpiece (10) provided with gearing (11) and rotating about a rotation axis (Dw), teeth (3) of a gear-cutting tool (1) rotating about a rotation axis (Dz) are brought into engagement with teeth (12) of the workpiece (10), and the gear-cutting tool (1) and the workpiece (10) are moved relative to each other in a direction (AX+, AX−) parallel to the rotation axis (Dw). The thickness (dZ) of the teeth (3) of the gear-cutting tool (1) increases in the axial direction, starting from the respective front ends (4, 5) of the teeth, until a thickness maximum (dZmax) is reached. High material removal performances and long-term durability of the gear-cutting tool (1) are achieved in that, according to the invention, 2≤Bw/Bz≤20 applies (wherein Bw=width Bw of the teeth of the gearing (11) of the workpiece (10), Bz=width of the teeth (3) of the gear-cutting tool (1)), that the gear-cutting tool (1), before each pass of its teeth (3) through the tooth gaps (17) of the workpiece (10) in the respective axial directions (AX+, AX−), is positioned at a position (P1, P2) in which the thickness maximum (dZmax) of the teeth (3) of the gear-cutting tool (1) is situated outside the gearing (11) of the workpiece (10), and that as a consequence of the relative movement of the workpiece (10) and of the gear-cutting tool (1) in the axial direction (AX+, AX−), the teeth (3) of the gear-cutting tool (1) are each moved through the respective tooth gaps (17) of the gearing (11) of the workpiece (10) that are assigned to them, until the thickness maximum (dZmax) of each tooth (3) has exited the assigned tooth gap (17).

A gear manufacturing method includes a step of preparing a gear blank; a step (teeth cutting step) of cutting the gear blank to form a half-finished gear having a plurality of gear teeth; a step (heat treatment step) of heat-treating the half-finished gear having the gear teeth; and a step (form rolling step) of rolling the half-finished gear which is subjected to the heat treatment, in which the gear teeth of the half-finished gear which is subjected to the teeth cutting step is formed with protuberances on both sides in a circumferential direction, and at the form rolling step, the protuberances are pressed by a rolling die, so that the half-finished gear becomes a gear.

A gear manufacturing method includes a step of preparing a gear blank; a step (teeth cutting step) of cutting the gear blank to form a half-finished gear having a plurality of gear teeth; a step (heat treatment step) of heat-treating the half-finished gear having the gear teeth; and a step (form rolling step) of rolling the half-finished gear which is subjected to the heat treatment, in which the gear teeth of the half-finished gear which is subjected to the teeth cutting step is formed with protuberances on both sides in a circumferential direction, and at the form rolling step, the protuberances are pressed by a rolling die, so that the half-finished gear becomes a gear.

A method for machining the tooth flanks of a bevel gear workpiece includes carrying out correction machining of a concave tooth flank and a convex tooth flank of at least one tooth gap by, after machining using a first machine setting, cutting free of the concave tooth flank by the bevel gear workpiece executing a workpiece rotation in a first rotational direction having a predefined first absolute value in relation to a gear-cutting tool and/or cutting free the convex flank by the bevel gear workpiece executing a workpiece rotation in another rotational direction having a predefined second absolute value in relation to the gear-cutting tool, and finish machining the concave tooth flank using a second machine setting, which differs from the first machine setting, and finish machining the convex tooth flank using a third machine setting, which differs from the second machine setting.