An automatic device for locking of tool holders (12) on lathes and machinery performing machining by chip removal, particularly suitable to be used on multi-spindle and single spindle CNC lathes, on transfer machines, milling centres of any kind and, in general, on all types of machine tools which perform machining by chip removal, comprises a support body (14) anchored to the machine tool and surmounted by a plate (16), said device comprises, for each of said tool-holders (12), a pawl (18) provided with a female truncated-cone recess (24), cooperating with a nut screw (36) and moved automatically vertically to engage in contact with a truncated cone collar appendage (40) made in a recess (38) in the rear (12). The movement in the vertical direction of the pawls (18) is produced by means of individual motors (46), equipped with a shaft (48) which protrudes from their lower face and engages to the upper end of said nut screw (36).

A rotary cutting tool includes a disc-like central body having an outer peripheral surface. A peripheral support member extends circumferentially along the peripheral outer surface of the disc-like central body and provides support against centrifugal and cutting forces exerted on an insert pocket during a cutting operation. A radial support member extends radially along the disc-like central body to the peripheral support member. The radial support member structurally interacts with the peripheral support member to provide additional support for the insert pocket against centrifugal and cutting forces exerted on the insert pocket during a cutting operation. The radial support member and the peripheral support member have a three-dimensional topology that maximizes a stiffness-to-weight ratio of the rotary cutting tool. The rotary cutting tool may include a second radial support member extending radially along the disc-like central body to the peripheral support member.

A modular cutting tool includes a cutting head, a shank and a mechanism which assists in assembling and locks the cutting head to the shank. The cutting head includes a cutting portion rotatable about a central longitudinal axis and a cylindrical skirt extending axially from the cutting portion and terminating at a contact face disposed perpendicular to the longitudinal axis. The skirt has a number of curved inner surfaces which generally define a bore disposed about the longitudinal axis. The shank includes a cylindrical portion of a first diameter disposed about the central longitudinal axis and a central protrusion disposed in the bore of the cutting portion. The central protrusion has a second diameter less than the first diameter and extends longitudinally from a contact face disposed perpendicular to the longitudinal axis at a leading end of the cylindrical portion.

A modular cutting tool includes a cutting head, a shank and a mechanism which assists in assembling and locks the cutting head to the shank. The cutting head includes a cutting portion rotatable about a central longitudinal axis and a cylindrical skirt extending axially from the cutting portion and terminating at a contact face disposed perpendicular to the longitudinal axis. The skirt has a number of curved inner surfaces which generally define a bore disposed about the longitudinal axis. The shank includes a cylindrical portion of a first diameter disposed about the central longitudinal axis and a central protrusion disposed in the bore of the cutting portion. The central protrusion has a second diameter less than the first diameter and extends longitudinally from a contact face disposed perpendicular to the longitudinal axis at a leading end of the cylindrical portion.

A combined structure of an arbor and an arbor seat, including: an arbor, having a first assembling portion which has at least one first hole, each first hole having a first central axis; an arbor seat, having a second assembling portion which is disposed in the axial direction, and the first assembling portion and the second assembling portion being insertably connected with each other, the second assembling portion having at least one second hole which has a second central axis, when the first and second assembling portions are connected with each other in the axial direction, each second central axis is noncoaxial and nonoverlapped with the at least one first central axis; and wherein at least one said fastener is inserted into one said first hole and one said second hole, and urges one said first hole and one said second hole in axially opposite directions.

A combined structure of an arbor and an arbor seat, including: an arbor, having a first assembling portion which has at least one first hole, each first hole having a first central axis; an arbor seat, having a second assembling portion which is disposed in the axial direction, and the first assembling portion and the second assembling portion being insertably connected with each other, the second assembling portion having at least one second hole which has a second central axis, when the first and second assembling portions are connected with each other in the axial direction, each second central axis is noncoaxial and nonoverlapped with the at least one first central axis; and wherein at least one said fastener is inserted into one said first hole and one said second hole, and urges one said first hole and one said second hole in axially opposite directions.

A rotary tool can be adapted for removing material from a workpiece such as a lower receiver. A rotary tool can have an adapter with a major diameter, and a cutter head with a minor diameter. The major diameter of the adapter can reduce deflection and chatter, while the minor diameter of the cutter head can be used to manufacture lower receivers with accuracy. The rotary tool can be adapted to be engaged with a rotary power tool.

A tool holder having a main body for coupling the tool holder to the spindle of a machine tool and having a clamping surface connected thereto for clamping a tool, characterized in that the tool holder has at least one portion shaped in one piece by primary shaping, which in its interior has one or more cavities that form an enclave in the portion shaped by primary shaping.

A tool holder having a main body for coupling the tool holder to the spindle of a machine tool and having a clamping surface connected thereto for clamping a tool, characterized in that the tool holder has at least one portion shaped in one piece by primary shaping, which in its interior has one or more cavities that form an enclave in the portion shaped by primary shaping.

A combined structure of an arbor and an arbor seat, including: an arbor, having a first assembling portion which has at least one first hole, each first hole having a first central axis; an arbor seat, having a second assembling portion which is disposed in the axial direction, and the first assembling portion and the second assembling portion being insertably connected with each other, the second assembling portion having at least one second hole which has a second central axis, when the first and second assembling portions are connected with each other in the axial direction, each second central axis is noncoaxial and nonoverlapped with the at least one first central axis; and wherein at least one said fastener is inserted into one said first hole and one said second hole, and urges one said first hole and one said second hole in axially opposite directions.