A method for grinding or polishing a gearwheel in a grinding or polishing machine, wherein the machine has two workpiece spindles for receiving a workpiece and a grinding or polishing spindle with a grinding or polishing tool. The method has the steps of: a) Grinding or polishing a first workpiece on a workpiece spindle; b) In a temporally parallel manner to the grinding or polishing of the first workpiece: Receiving a second workpiece on the further workpiece spindle and measuring the toothing of the workpiece to determine the positions of the tooth gaps, the measurement including scanning the tooth or profile flanks of at least one tooth by a tactile measuring element or by contactless measuring, in order to determine the effective oversize on the tooth flanks; c) Following completion of grinding or polishing the first workpiece: Grinding or polishing the second workpiece on the further workpiece spindle based on the determined positions of the tooth gaps and/or the measured effective oversize on the tooth.

A machine tool that generates internal teeth or external teeth on a cylindrical workpiece includes a workpiece holder, a column which is relatively movable to the workpiece holder, a rotary main spindle which is rotatable with respect to the column, a working tool which is held by the rotary main spindle, and a phase detecting unit which detects a phase of the working tool with respect to the rotary main spindle. The working tool includes a cutter portion which has cutters, a holder portion, and a detected portion which is formed on the holder portion. The phase detecting unit includes a detecting section which detects the detected portion, and a calculating section which calculates a phase angle of the detected portion with respect to a reference position of the rotary main spindle, based on a result detected by the detecting section.

A method for machining a workpiece to provide a toothed member having a desired tooth pattern. The workpiece is machined to a first depth using a cutting tool, thereby forming a semi-finished tooth pattern, the first depth less than a full depth to which the workpiece is to be machined to provide the desired tooth pattern. Dimensions of the semi-finished tooth pattern are acquired and compared to nominal dimensions. If the acquired dimensions are not within a tolerance of the nominal dimensions, the geometry of the cutting tool is modified for correcting deviations of the acquired dimensions from tolerance and the workpiece further machined by the modified cutting tool. Once the dimensions of the semi-finished tooth pattern are within tolerance, the workpiece is machined to the full depth for providing the desired tooth pattern.

A gear machining apparatus includes: a hob cutter; at least one processor; and at least one memory having instructions. The instructions, when executed by the at least one processor, cause the gear machining apparatus to perform operations including: performing first chamfering on a first axial end of a gear profile by relatively moving the hob cutter with respect to a workpiece in radial and axial directions of the workpiece; performing, subsequent to the first chamfering, gear profile machining by relatively moving the hob cutter with respect to the workpiece in the axial direction; and performing, subsequent to the gear profile machining, second chamfering on a second axial end of the gear profile by relatively moving the hob cutter with respect to the workpiece in the radial and axial directions.

A method for dressing a multiple thread grinding worm by a dressing tool, in which the abrasive surfaces of the individual threads of the grinding worm are successively profiled with the dressing tool. The dressing is carried out in at least two threads with different dressing parameters so that the profiling of the abrasive surfaces of the threads differ from each other. The dressing parameters are selected so that the abrasive surfaces of at least two threads, viewed in the direction of the helix of the thread, differ from one another, and/or that the abrasive surfaces of the individual threads are profiled by topological dressing. A plurality of linear dressing strokes are performed over the height of the abrasive surface. The dressing tool is guided in the radial direction of the grinding worm at predetermined distances. The distances are constant in each thread but differing in at least two threads.

A gear machining apparatus includes: a hob cutter; at least one processor; and at least one memory having instructions. The instructions, when executed by the at least one processor, cause the gear machining apparatus to perform operations including: performing first chamfering on a first axial end of a gear profile by relatively moving the hob cutter with respect to a workpiece in radial and axial directions of the workpiece; performing, subsequent to the first chamfering, gear profile machining by relatively moving the hob cutter with respect to the workpiece in the axial direction; and performing, subsequent to the gear profile machining, second chamfering on a second axial end of the gear profile by relatively moving the hob cutter with respect to the workpiece in the radial and axial directions.

Apparatus with a rotationally drivable receptacle for a grinding tool to be tested, wherein the apparatus comprises: an optical testing apparatus arranged such that the grinding tool, while being rotatably driven, is at least partially irradiated by light emanating from an emitter of the testing apparatus, and that at least a portion of the light from the grinding tool is reflectable in the direction towards a sensor of the testing apparatus, wherein the sensor is adapted to provide test information, a computing device which is designed for processing the test information in order to determine a 3-dimensional vector model of the grinding tool from macroscopic basic information, a memory in which a target vector model is stored, a computing device which is designed for comparing the vector model with the target vector model in order to enable the determination of deviations between the vector models.

A method which is executed in a grinding machine comprising a) rotationally driving a cup grinding wheel around an axis of rotation of a tool spindle at a first speed, b) rotationally driving a dressing tool around an axis of rotation of a dressing spindle at a second speed, c) carrying out a dressing method using the dressing tool, wherein a predetermined, fixed speed ratio is specified between the first speed and the second speed, and after steps (a), (b), and (c): i. eccentrically rotationally driving the cup grinding wheel around the axis of rotation of the tool spindle at a first machining speed using the eccentric drive, ii. carrying out a grinding method, wherein the bevel gear workpiece is machined by grinding using the cup grinding wheel.

A gearwheel, wherein the gearwheel has a setpoint geometry, wherein the gearwheel has a modification superimposed on the setpoint geometry in the form of a pitch and/or topography changing from tooth to tooth, wherein a variation of the pitch and/or topography specified by the modification, observed over a total number of teeth of the gearwheel, corresponds to a superposition of at least two harmonic functions, which differ from one another in one parameter or in multiple parameters, such as their amplitude, frequency, or phase shift.

A method for monitoring a machining process in which tooth flanks of pre-toothed workpieces (23) are machined with a finishing machine (1) is disclosed. As part of the method, a plurality of measurement values are recorded while a finishing tool (16) is in machining engagement with a workpiece. Among them are values of a power indicator which indicates a current power consumption of the tool spindle during the machining of the tooth flanks of the workpiece. A normalization operation is applied to at least some of the measurement values or to values of a quantity derived from the measurement values in order to obtain normalized values. The normalization operation depends on at least one of the following parameters: geometrical parameters of the finishing tool, in particular its outside diameter, geometrical parameters of the workpiece and setting parameters of the finishing machine, in particular radial infeed and axial feed.