A bit-removal assembly includes a first ring coupled to an output shaft for co-rotation therewith, a second ring supported on the lower retaining ring of the output shaft, a frusto-conical surface on at least one of the first or second rings, and a wedge positioned between the first and second rings and engaging with the frusto-conical surface. A collar defines a cam surface located radially outward of the wedge. The collar is movable between a locked position, in which the cam surface is engaged with the wedge to displace the wedge radially inward on the frusto-conical surface to separate the second ring from the first ring, and a released position, in which the cam surface is misaligned with the wedge to permit the wedge to move radially outward on the frusto-conical surface. A biasing member urges the collar towards the locked position.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes a back-tapered conical external thread. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A tool holder includes a main body defining a mounting end and a receiving end, the mounting end positioned opposite from the receiving end, the main body defining a main body bore extending into the receiving end toward the mounting end; an extension defining a tool head attached to a rod, the tool head defining a tool head end opposite from the rod, a tool holder length defined between the mounting end and the tool head end, the tool head configured to receive at least one cutting tool, the rod received within the main body bore; and a locking mechanism engaging the extension and the main body in a locked position, the locking mechanism being disengaged from either the main body or the extension in an unlocked position, the locking mechanism being selectively positionable about and between the locked position and the unlocked position.

A tool holder includes a main body defining a mounting end and a receiving end, the mounting end positioned opposite from the receiving end, the main body defining a main body bore extending into the receiving end toward the mounting end; an extension defining a tool head attached to a rod, the tool head defining a tool head end opposite from the rod, a tool holder length defined between the mounting end and the tool head end, the tool head configured to receive at least one cutting tool, the rod received within the main body bore; and a locking mechanism engaging the extension and the main body in a locked position, the locking mechanism being disengaged from either the main body or the extension in an unlocked position, the locking mechanism being selectively positionable about and between the locked position and the unlocked position.

A method and rivet apparatus comprise a rivet block, the rivet block comprising a rivet block, a pin bore, and a rivet feed bore. The rivet block is comprised of a top end and a bottom end. The pin bore includes a top end and a bottom end and is disposed within the rivet block. The pin bore extends from the top end to the bottom end of the rivet block and guides a rivet pin that slides downward within the pin bore to push a head of a rivet into a workpiece. The rivet feed bore includes a top end and a bottom end and is disposed within the rivet block. The rivet feed bore extends from the top end to the bottom end of the rivet block, accepts the rivet at the top end of the rivet feed bore, and guides the rivet to the bottom end of the rivet feed bore. The rivet feed bore intersecting the pin bore between the top end and the bottom end of the pin bore at an oblique angle.

An electrospindle includes a motor for moving a tool and a motor shaft for transmitting motion from the motor to the tool. The electrospindle has a gripping head of the tool and a coupling of the tool to the motor shaft, and the gripping head includes two flanges, between which a portion of the tool and at least one thrust nut of a first flange can be interposed toward a counterflange, so as to hold the tool in position. The transmission has a free end threaded so as to receive the at least one thrust nut by screwing, the thread of the free end being double with a first right-handed thread and a second left-handed thread.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes an external thread defined by external inner and outer cylinders. The external thread has concavely curved external thread roots which each merge with a respective straight external loaded surface at a first external root point. The first external root point is spaced apart from the external inner cylinder by a first external radial distance. The first external radial distance is greater than a third and less than two thirds of the external thread height. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A connection device for connecting a tool holder (4) to a drive unit (2), which are provided on adjacently opposite contact surfaces with a serration (124, 56) each, which can be brought into engagement with each other and having a retraction device (90, 118), which reduces an axial distance between the serrations (124, 56) until they are in contact with each other.

An angle head holder has a steering assembly and a holder assembly rotatably mounted in the steering assembly. The holder assembly has a cutter spindle, a threaded rod, multiple balls, and a collet. The cutter spindle has a central hole and a first annular groove radially formed in the central hole at a position near a rear end of the cutter spindle. The threaded rod has a second annular groove aligning with the first annular groove to form a ball groove between the threaded rod and the cutter spindle. The balls are arranged in the ball groove. The collet is inserted in the central hole of the cutter spindle from a front end of the cutter spindle and is connected to the threaded rod with threaded connection.

A drilling tool includes a cutting part and a clamping part. The cutting part includes a cutting portion and a connecting portion connected to a lower end of the cutting portion. The connecting portion has an outer peripheral surface, and the clamping part has an inner peripheral surface. A recess of the outer peripheral surface is spirally twisted into a protrusion of the inner peripheral surface in a direction of a central axis. In the process of clamping the cutting part on the clamping part, the outer peripheral surface and the inner peripheral surface fit together with a varying interference amount λ, which meets the following requirements: −0.1 mm≤λ≤0.05 mm.