Abstract:
The invention concerns a method of machining a workpiece, wherein an end-facing tooth edge of a gear profile of the workpiece that was generated by a chip-removing machining process is reworked at a first location into a chamfered edge by way of a plastic forming operation. The material which in the plastic forming operation was displaced towards the end surface of the gear profile is pushed outward as a material protrusion in the end surface of the tooth, while the material displaced towards the flank of the tooth is pushed outward as a material protrusion on the flank side of the chamfer, and the resulting material protrusions in the end surface and on the flank side are removed. The workpiece, while still carrying the material protrusion on the end surface of the gear profile, is transferred to a second location where the protrusion on the flank side of the chamfer is removed.
Abstract:
A disclosed method utilizes virtual representations of gear profiles produced in view of accuracies and capabilities of specific machine and tool combinations to validate profile finishing parameters. The virtual representations are utilized to identify modifications needed to account for process capability and are implemented into the process to change the nominal profile utilized for producing the finished gear profiles. The resulting nominal gear profile accounts for process variations and thereby provides a more accurate and repeatable gear tooth profile.
Abstract:
A method for shaving and shave grinding tooth flanks of cylindrical workpiece gear wheels, especially, flank-line modified gear wheels, and for profiling tools needed for shave-grinding cylindrical workpiece gear wheels. During the machining of gear wheels, certain areas of the gear wheel need to be machined more so than other areas, meaning that some areas require more material to be removed than other areas. As a result, certain areas of the tool are not uniformly worn, but rather the area of the tool which removes the most material is worn more quickly than other areas of the tool. Similarly, if certain areas of the gear wheel are harder than other areas, the tool performing the actual machining will wear at a corresponding rate. The present invention avoids such non-uniform wear by providing greater areas of cutting surface on the tool performing the actual machining in the positions which are required to remove the most material, or which are required to machine the hardest surfaces of the workpiece.
Abstract:
A secondary working apparatus for secondarily machining a blank formed with internal serrations on a cylindrical plane, comprising a stationary housing structure, support means for supporting the blank with the center axis of the cylindrical plane fixed with respect to the housing structure, a plurality of shafts each having a center axis parallel with the center axis of the cylindrical plane and rotatable with respect to the housing structure about an axis coincident with the center axis of the shaft and an axis coincident with the center axis of the cylindrical plane, each of the shafts having a cylindrical eccentric axial portion having a center axis parallel with and radially offset from the center axis of the shaft, cylindrical machining tools coaxially carried on the eccentric axial portions of the shafts, respectively, and each having a center axis coincident with the center axis of the eccentric axial portion of each of the shafts, and an annular guide gear coaxially held in position about the center axis of the cylindrical plane and formed with internal teeth to be held in mesh with the internal serrations of the blank, the internal teeth being equal in number to the internal serrations of the blank and being cut with outwardly shifted tooth profiles, the guide gear being preferably constructed of highly elastic metal, such as spring steel.
Abstract:
A shaving cutter having a circular array of teeth of the same number and approximate size as that of a gear to be shaved, and having cutting edges at one end of the teeth of identical profile as that to be formed on the gear teeth, the teeth of the cutter being backed off to provide cutting clearance and dimensioned to be received simultaneously in all of the tooth spaces of the gear with circumferential clearance. Relative reciprocation is provided with timed relative circumferential depth feed to shave first one side and then the other of the gear teeth. The teeth are provided with cutting edges occupying different planes to avoid having all teeth initiate cutting action at the same time.
Abstract:
The axis of rotation of a gear wheel subjected to thermal treatment and comprising at least one intermediate crown wheel and a pair of lateral tubular hubs arranged on opposite sides of the crown wheel is restored automatically by coupling a first of the hubs to a head rotating about a fixed axis of own rotation axis, displacing the other hub in a direction transverse to the fixed axis until both of the hubs and the crown wheel are brought into positions substantially sharing the fixed axis and providing on each of the hubs a respective centring surface sharing the fixed axis without uncoupling the first hub from the rotating head and keeping the gear wheel in a vertical and angularly fixed position.