A plurality of cutting edges that are arranged on an outer circumference of a shaft-shaped broach body are provided with a spline teeth group, which contains a plurality of spline teeth 8 that groove a prepared hole of a work material, and a round teeth group, which is disposed in a different position from the spline teeth group along an axis direction and contains a plurality of round teeth that machine an inner circumference of the prepared hole. At least one gullet is formed to extend along the outer circumference of the broach body in a circumferential direction around the axis between the round teeth that are adjacent to one another in the axis direction in the round teeth group. The gullet extends toward the axis direction, gradually twisting toward the circumferential direction. The spline teeth group and the round teeth group are formed integrally on the outer circumference of the broach body.

A broach for a broaching machine is disclosed, the broach being usable for machining parts by stripping off material, having at least one tooth for stripping off the material, which has a detaching face for stripping off material and a back face for receiving stripped material, in addition to two side faces and an cutting face joining the detaching face with the back face; a blade for locating the at least one tooth; a chip chamber as an open cavity, the chip chamber being located longitudinally immediately after the cutting face; and a leading edge for cutting the part to be machined, the leading edge being configured with a rounded shape, which is located in correspondence with a union of the detaching face with the cutting face.

A helical broach which eliminates the need for a fixing means for fixing a workpiece during gear machining is provided. The helical broach includes: a plurality of cutting edges; a spiral flute formed between adjacent cutting edges to extend in a spiral manner with a predetermined helix angle with respect to an axial direction of the helical broach; and a gullet formed between adjacent cutting edges to extend with a predetermined helix angle with respect to a circumferential direction of the helical broach. In the helical broach, the expression: 0.5tan /tan(+)0.7 is satisfied, wherein is the helix angle of the spiral flute, and (90) is the helix angle of the gullet with reference to a central axis of the helical broach. An internal gear machining method using the helical broach is also provided.

A helical broach which eliminates the need for a fixing means for fixing a workpiece during gear machining is provided. The helical broach includes: a plurality of cutting edges; a spiral flute formed between adjacent cutting edges to extend in a spiral manner with a predetermined helix angle with respect to an axial direction of the helical broach; and a gullet formed between adjacent cutting edges to extend with a predetermined helix angle with respect to a circumferential direction of the helical broach. In the helical broach, the expression: 0.5tan /tan(+)0.7 is satisfied, wherein is the helix angle of the spiral flute, and (90) is the helix angle of the gullet with reference to a central axis of the helical broach. An internal gear machining method using the helical broach is also provided.

A broaching tool, comprising a shank, a body and a cutting head that comprises at least one rake face. The rake face comprises a cutting edge that comprises a cutting corner at a forward end of the cutting head. The rake face is configured such that upon simultaneously rotating the broaching tool about the axis of the broaching tool and advancing the broaching tool along the axis of the broaching tool in a forward direction, the first corner travels in a first circular helix pattern. Also, a method of forming one or more grooves in a bore-containing structure, the method comprising simultaneously rotating a broaching tool and a bore-containing structure relative to one another about the axis, and moving the broaching tool and the bore-containing structure relative to one another along the axis. Also, methods of making broaching tools, and broaching machines.

A broaching tool, comprising a shank, a body and a cutting head that comprises at least one rake face. The rake face comprises a cutting edge that comprises a cutting corner at a forward end of the cutting head. The rake face is configured such that upon simultaneously rotating the broaching tool about the axis of the broaching tool and advancing the broaching tool along the axis of the broaching tool in a forward direction, the first corner travels in a first circular helix pattern. Also, a method of forming one or more grooves in a bore-containing structure, the method comprising simultaneously rotating a broaching tool and a bore-containing structure relative to one another about the axis, and moving the broaching tool and the bore-containing structure relative to one another along the axis. Also, methods of making broaching tools, and broaching machines.

A tool (2) for machining workpieces, comprising a carrier (4) rotating in an axial direction (A) during operation, and further comprising multiple cutting segments (6), which are fastened to the carrier (4) in a radial direction (R), characterized in that at least one hydraulic clamping unit (21) is attached to the carrier (4) for clamping at least one of the cutting segments (6) to the carrier (4).

A tool (2) for machining workpieces, comprising a carrier (4) rotating in an axial direction (A) during operation, and further comprising multiple cutting segments (6), which are fastened to the carrier (4) in a radial direction (R), characterized in that at least one hydraulic clamping unit (21) is attached to the carrier (4) for clamping at least one of the cutting segments (6) to the carrier (4).

A helical broach which eliminates the need for a fixing means for fixing a workpiece during gear machining is provided. The helical broach includes: a plurality of cutting edges; a spiral flute formed between adjacent cutting edges to extend in a spiral manner with a predetermined helix angle with respect to an axial direction of the helical broach; and a gullet formed between adjacent cutting edges to extend with a predetermined helix angle with respect to a circumferential direction of the helical broach. In the helical broach, the expression: 0.5tan /tan(+)0.7 is satisfied, wherein is the helix angle of the spiral flute, and (90) is the helix angle of the gullet with reference to a central axis of the helical broach. An internal gear machining method using the helical broach is also provided.

A helical broach which eliminates the need for a fixing means for fixing a workpiece during gear machining is provided. The helical broach includes: a plurality of cutting edges; a spiral flute formed between adjacent cutting edges to extend in a spiral manner with a predetermined helix angle with respect to an axial direction of the helical broach; and a gullet formed between adjacent cutting edges to extend with a predetermined helix angle with respect to a circumferential direction of the helical broach. In the helical broach, the expression: 0.5tan /tan(+)0.7 is satisfied, wherein is the helix angle of the spiral flute, and (90) is the helix angle of the gullet with reference to a central axis of the helical broach. An internal gear machining method using the helical broach is also provided.