A perforating apparatus for a cylindrical workpiece, including: a cradle having a groove extending in one direction horizontally from one end to another end; a stopper provided at the one end of the groove; a drill disposed vertically above the groove and movable at least in vertical direction, having a drill bit that extends vertically; and a chuck having a pair of opposing grippers movable toward each other in a horizontal direction perpendicular to the direction in which the groove extends, and symmetrically with respect to a rotation axis of the drill bit, each of the grippers further having a pair of vertically symmetric inclined surfaces expanding upwards and downwards.

A fixing device for securing a thin-walled component according to an embodiment includes: a support; a pressing portion provided on the support and including: a pressure generator located at a center of the support; and a plurality of pressure transmitters arranged around the pressure generator and extending in a radial direction of the thin-walled component; and a plurality of elastic members connected to the plurality of pressure transmitters, wherein the plurality of pressure transmitters are configured to move the plurality of elastic members in the radial direction.

A wheel rim chuck has a chuck seat (10) and multiple soft jaws (20). The soft jaws are arranged radially at equiangular intervals and slidably mounted on the chuck seat (10). Each soft jaw (20) has a claw (21) having a protrusion (211), a clamping groove (213), and an inclined plane (216). The protrusion (211) protrudes from a side of the soft jaw (20) away from the chuck seat (10). The clamping groove (213) is recessed in a side of the protrusion (211) facing the center (111) of the chuck seat (10) and having a side wall (214) and a bottom wall (215). The inclined plane (216) extends longitudinally and obliquely from the bottom wall (215) away from the side wall (214) of the clamping groove (213).

A chuck mechanism of the present invention includes multiple master jaws placed movably in a radial direction on a front surface of a chuck body, and top jaws each detachably attached to front surfaces of the top jaws. Each master jaw and each top jaw have a raised portion and a recessed portion engageable with each other. Each of the raised and recessed portions has conical surfaces formed by part of a conical body. Each top jaw has a gripping surface formed by part of a circular columnar body. Upon work gripping, the center axes of the conical surfaces on a gripping side among the conical surfaces of each master jaw and each top jaw and the center axis of the gripping surface are all coincident with a rotation axis of the chuck body.

The present invention is a novel machine for repairing damaged wheel rims whereby the machine is a combination CNC and manual lathe configured of performing all of the required tasks for repairing damaged wheel rims in a single unit.

A device for holding a workpiece that includes a first clamping element and at least one second clamping element, wherein the first clamping element and the second clamping element each include on an end side extending in a radial plane a first engagement structure and at least one second engagement structure at different radial positions configured to engage at a first time an end side of a first workpiece having a first diameter and at a second time an end surface of a second workpiece of a second diameter different than the first diameter for holding the workpiece by moving the first clamping element and the second clamping element in the radial direction.

A projecting part 11A and a recessed part 12A which engage with each other are formed on a master jaw 11 and a top jaw 12. In the master jaw 11, a movable pin 20 movable in an axial direction and a shaft 30 movable in a radial direction is disposed, and the movable pin 20 is engaged with the shaft so that the movable pin 20 can be moved in the axial direction. The top jaw 12 is provided with a pin hole 12c into which the movable pin 20 can be inserted. The movable pin 20 is locked, by rotating the shaft 30 by a predetermined amount, at a first position in which the movable pin 20 is inserted in the pin hole 12c or at the second position in which the movable pin 20 is extracted from the pin hole 12c.

Intrusion of chips is prevent into gaps formed between inner end surfaces of master jaws and a chuck cover. A top plate is disposed at the center of an end surface of a chuck body. Top covers, which move in conjunction with movements of master jaws when opening and closing the chuck, are disposed in top cover guide recesses formed at three positions on the top plate. Each top cover abuts the center-side end parts of serrated surfaces formed on both widthwise sides of a respective master jaw and the center-side end part of a step section of a stepped claw therebetween, and the top covers close gaps formed at the center-side end parts by the movements of the master jaws at all times by moving in conjunction with movement of the master jaws.

A clamping jaw for a chuck includes a jaw body on which there is formed at least one jaw step having a step head, which has a sensor on its end face, for holding a clamping insert which is formed from a base leg and two fastening legs projecting from the base leg. On each of the opposite longitudinal sides of the step head there is formed a threaded bore for receiving a fastening screw whose screw head is received in a through-opening which is formed in the fastening leg of the clamping insert that is assigned to the longitudinal side, wherein, on each side, the longitudinal axes of the threaded bore and of the through-opening assigned thereto have an offset when the base leg bears against the end face. Also, a chuck has a chuck body, in which such clamping jaws are arranged in uniformly-distributed radial jaw guides.

A system for removing an electrode cap from an electrode shaft. The system includes at least one electrode cap removal device which is mounted to rotate about a tool axis of rotation. The at least one electrode cap removal device has a clamping device for fixing the electrode cap to be removed. The clamping device is a combination of a straight-toothed clamping device and a helical-toothed clamping device.