A method of manufacturing a gear is provided. The method includes forming a plurality of gear teeth in a surface of a gear, the gear teeth having tooth faces defining tooth edges including tooth edge flanks and tooth edge top land and generating a convex contour at an edge break of at least one of the tooth edge flanks and tooth edge top land.

A spark erosion machine includes a frame with a space for spark erosion of a workpiece, a wire for cutting by spark erosion, and a wire guide head for guiding the wire across the workpiece, so as to detach an offcut from it; an offcut support mounted movably relative to the guide head, the support being configured to move at least between a retention position under the spark erosion space, where it can collect the offcut, and a retracted position; and an offcut extractor.

A herringbone gear includes a cylindrical body having a circumferential face having a width. A first helical gear tooth on the circumferential face has a first configuration, a second helical gear tooth on the circumferential face has a second configuration, and a transition on the circumferential face extends between the first helical gear tooth and the second helical gear tooth. An involute form taken within a transverse plane of the circumferential face remains constant over the width.

An apparatus for electrochemical machining gear outline and the alignment structure thereof is disclosed, the apparatus comprises first and second alignment members. The first and second alignment members include a plurality of first alignment teeth and second alignment teeth, respectively. Recessing a gear-outline edge of the first alignment teeth by a distance and extending a gear-outline edge of the second alignment teeth by the distance for against to each other to align the first and second alignment members. A cathode electrode includes a plurality of machining teeth with both gear-outline edges recessed by the distance for against the gear-outline edge of the second alignment teeth with the extended distance to align machining teeth. Thereby, before trimming the gear-outline of a workpiece, the machining gap between the machining teeth and the teeth of the workpiece can be aligned first.

A method of manufacturing a gear, the method includes applying a first charge to a workpiece and applying a second, opposite charge to an electrochemical machining (ECM) attachment, the ECM attachment having a pattern. The method further includes simultaneously forming a plurality of surfaces of a gear tooth in the workpiece using the pattern of the ECM attachment while applying the first charge to the workpiece and applying the second charge to the ECM attachment and turning the workpiece and the ECM attachment in opposite rotational directions. The plurality of surfaces includes at least one end face and a top land of the gear tooth.

A method of manufacturing a gear, the method includes applying a first charge to a workpiece and applying a second, opposite charge to an electrochemical machining (ECM) attachment, the ECM attachment having a pattern. The method further includes simultaneously forming a plurality of surfaces of a gear tooth in the workpiece using the pattern of the ECM attachment while applying the first charge to the workpiece and applying the second charge to the ECM attachment and turning the workpiece and the ECM attachment in opposite rotational directions. The plurality of surfaces includes at least one end face and a top land of the gear tooth.

The present invention relates to an electrochemical machining apparatus for gear outline, which is used for trimming the gear outline of the gear part of a workpiece and comprises a first moving mechanism, a second moving mechanism, a cathode electrode, and a gear alignment member. The cathode electrode is disposed at the first moving mechanism. The second moving mechanism is connected with the gear alignment member. The gear alignment member includes a plurality of alignment gears for aligning the location of a plurality of teeth of the gear part of the workpiece. Thereby, the plurality of teeth of the workpiece may correspond to the cathode electrode. Then, the cathode electrode may perform electrochemical machining on the plurality of teeth, and thus, trimming the outline of the plurality of teeth.

A method of manufacturing a gear is provided. The method includes forming a plurality of gear teeth in a surface of a gear, the gear teeth having tooth faces defining tooth edges including tooth edge flanks and tooth edge top land and generating a convex contour at an edge break of at least one of the tooth edge flanks and tooth edge top land.

A herringbone gear includes a cylindrical body having a circumferential face having a width. A first helical gear tooth on the circumferential face has a first configuration, a second helical gear tooth on the circumferential face has a second configuration, and a transition on the circumferential face extends between the first helical gear tooth and the second helical gear tooth. An involute form taken within a transverse plane of the circumferential face remains constant over the width.

A spark erosion machine includes a frame with a space for spark erosion of a workpiece, a wire for cutting by spark erosion, and a wire guide head for guiding the wire across the workpiece, so as to detach an offcut from it; an offcut support mounted movably relative to the guide head, the support being configured to move at least between a retention position under the spark erosion space, where it can collect the offcut, and a retracted position; and an offcut extractor.