Abstract: An indexable ball end mill comprising first to third inserts having arcuate cutting edges detachably attached with first to third screws to first to third seats in a semispherical tip end portion of a tool body; a first threaded hole for the first screw slantingly penetrating a slit-shaped first seat; the first insert having an inclined hole to avoid interference between the first screw and the second and third screws; a hole of the first insert and the first screw having at least partially finished surfaces, so that when the first screw penetrates the first insert attached to the first seat, the first insert is precisely positioned by tight engagement of both finished surfaces.

Abstract: An indexable ball end mill comprising first to third inserts having arcuate cutting edges detachably attached with first to third screws to first to third seats in a semispherical tip end portion of a tool body; a first threaded hole for the first screw slantingly penetrating a slit-shaped first seat; the first insert having an inclined hole to avoid interference between the first screw and the second and third screws; a hole of the first insert and the first screw having at least partially finished surfaces, so that when the first screw penetrates the first insert attached to the first seat, the first insert is precisely positioned by tight engagement of both finished surfaces.

Abstract: This aims to provide a ball end mill capable of preventing the occurrence of a ‘pluck’ off a work face. The ball end mill (10) is equipped with two cutting edges (11 and 12) formed at its spherical tips. The rake face (11a) of the cutting edge (11) has its inner circumference end arranged at a position offset farther forward of a rotating direction than a spindle. The rake face (11a) of the cutting edge (11) has its inner circumference end arranged at a position protruding by a predetermined distance from the spindle to the opposite side of the cutting edge forming side in the radial direction. The portion of the cutting edge (11) from a connecting portion (11f), which is formed midway of a ridgeline (11c) or a boundary line between the rake face (11a) of the cutting edge (11) and a flank (11b), to the outer circumference end of the cutting edge (11) is a main cutting edge (11m).

Abstract: This aims to provide a ball end mill capable of preventing the occurrence of a ‘pluck’ off a work face. The ball end mill (10) is equipped with two cutting edges (11 and 12) formed at its spherical tips. The rake face (11a) of the cutting edge (11) has its inner circumference end arranged at a position offset farther forward of a rotating direction than a spindle. The rake face (11a) of the cutting edge (11) has its inner circumference end arranged at a position protruding by a predetermined distance from the spindle to the opposite side of the cutting edge forming side in the radial direction. The portion of the cutting edge (11) from a connecting portion (11f), which is formed midway of a ridgeline (11c) or a boundary line between the rake face (11a) of the cutting edge (11) and a flank (11b), to the outer circumference end of the cutting edge (11) is a main cutting edge (11m).

Abstract: Method of generating tool movement path data 9 includes determining a tool constraining surface (12) which is offset from a three-dimensional surface (22) to be generated, by a distance equal to a radial dimension of rotary machining tool (20), in a direction normal to the three-dimensional surface, determining tool path constraining surfaces (32) for constraining the tool according to the geometry of the three-dimensional surface, and obtaining three-dimensional curved line equations representing intersection lines (34) between the constraining surfaces (12, 32). Since desired curved surfaces may be used as the tool path constraining surfaces (32), the tool movement path can be suitably determined with high freedom depending upon the geometry of the three-dimensional surface (22) to be generated.

Abstract: A process of generating discrete points to be followed by a cutter during movements of the cutter to machine a workpiece, including a step of operating a computer including a data processor, to select at least one of different discrete point generating conditions stored in a memory of the computer, according to a command entered by an operator of the computer, each discrete point generating condition including at least one requirement that should be satisfied when the discrete points are generated so as to define a cutter path, a step of operating the computer to calculate an interval of the discrete points, according to the selected discrete point generating condition or conditions, and a step of operating the computer to generate the discrete points on the basis of the calculated interval, such that the discrete points are spaced apart from each other by the interval. The discrete point generating conditions may include requirements associated with velocities of the cutter during machining of the workpiece.

Abstract: A process of generating a succession of discrete points to be followed by a cutter, so as to move the cutter along a desired cutter path, including a step of calculating a space interval of the discrete points in the direction of the succession on the basis of a curvature radius of the desired cutter path, according to a relationship among the curvature radius, the space interval and movement velocity of the cutter, such that the movement velocity is enlarged as much as possible, and a step of generating the discrete points on the basis of the space interval, such that the discrete points are spaced apart from each other by a distance equal to the space interval in the direction of the succession.