Abstract: A machining apparatus includes: a shuttle unit (3) that holds a differential case (10) and rotates the differential case (10); a pair of opposed right and left machining units (4); and a tool support (6) that supports a tool (40) for machining the differential case (10), in which the pair of right and left machining units (4) each include a slide mechanism dedicated for uniaxial sliding in right and left directions, the shuttle unit (3) is movable in up and down directions and front and back directions, a tool attached to each of the pair of right and left machining units (4) enables machining an end portion of an inner surface of the differential case (10) and a flange hole of the differential case (10), the end portion surrounding a through hole, and a cutting edge of the tool (40) supported by the tool support (6) enables spherically cutting the inner surface of the differential case (10) held and rotated by the shuttle unit (3).

Abstract: A cutting tool for boring (40) that is attached to a machining apparatus and used for cutting a hole (13) on a large-diameter side of a stepped hole of a workpiece (10) is provided. The cutting tool for boring (40) is a set of two tools, and each cutting tool for boring (40a, 40b) in the set of two includes a shaft part (41), a cutting blade (42) laterally protruding from the respective shaft parts (41), and an abutment surface (43) formed at the tip of each shaft part (41) and used to cause the tips of the respective shaft parts (41) to butt against each other. Each cutting tool for boring (40a, 40b) performs cutting while the two cutting tools for boring (40a, 40b) rotate integrally around the center line of the shaft parts (41) in a coupled state in which the tips of the cutting tools for boring (40a, 40b) are butted together.

Abstract: A cutting tool (35) for machining a differential case, the cutting tool (35) being attached to a machining apparatus and used to perform cutting on a spherical inner surface of a differential case (10), the cutting tool (35) including: a shaft part (50); a cutting edge (51) laterally protruding from the shaft part (50); a fixing part (53) formed at one end side of the shaft part (50) and that is for fixing the shaft part (50) to the machining apparatus; and a retaining part (54) formed at the other end side of the shaft part (50) and that is for retaining the shaft part (50) by the machining apparatus, wherein the cutting tool (35) is able to perform cutting on the spherical inner surface of the rotating differential case (10) in a both-ends-held state in which both the fixing part (53) and the retaining part (54) are supported by the machining apparatus.

Abstract: A cutting tool (35) for machining a differential case, the cutting tool (35) being attached to a machining apparatus and used to perform cutting on a spherical inner surface of a differential case (10), the cutting tool (35) including: a shaft part (50); a cutting edge (51) laterally protruding from the shaft part (50); a fixing part (53) formed at one end side of the shaft part (50) and that is for fixing the shaft part (50) to the machining apparatus; and a retaining part (54) formed at the other end side of the shaft part (50) and that is for retaining the shaft part (50) by the machining apparatus, wherein the cutting tool (35) is able to perform cutting on the spherical inner surface of the rotating differential case (10) in a both-ends-held state in which both the fixing part (53) and the retaining part (54) are supported by the machining apparatus.

Abstract: A machining apparatus includes: a shuttle unit (3) that holds a differential case (10) and rotates the differential case (10); a pair of opposed right and left machining units (4); and a tool support (6) that supports a tool (40) for machining the differential case (10), in which the pair of right and left machining units (4) each include a slide mechanism dedicated for uniaxial sliding in right and left directions, the shuttle unit (3) is movable in up and down directions and front and back directions, a tool attached to each of the pair of right and left machining units (4) enables machining an end portion of an inner surface of the differential case (10) and a flange hole of the differential case (10), the end portion surrounding a through hole, and a cutting edge of the tool (40) supported by the tool support (6) enables spherically cutting the inner surface of the differential case (10) held and rotated by the shuttle unit (3).