A chuck mechanism operates a piston in a cylinder tube by using action of compressed air and opens and closes, by using a rod coupled to the piston, a pair of fingers, thereby gripping work W. The locking mechanism locks the fingers at work grip positions. The locking mechanism includes a first locking member, a second locking member, and a drive device. The first locking member is displaced when the pair of fingers are opened or closed. The second locking member retains the first locking member so as to lock the fingers at the work grip positions. The drive device relatively displaces the first locking member and the second locking member to locking positions and non-locking positions.

A chuck mechanism operates a piston in a cylinder tube by using action of compressed air and opens and closes, by using a rod coupled to the piston, a pair of fingers, thereby gripping work W. The locking mechanism locks the fingers at work grip positions. The locking mechanism includes a first locking member, a second locking member, and a drive device. The first locking member is displaced when the pair of fingers are opened or closed. The second locking member retains the first locking member so as to lock the fingers at the work grip positions. The drive device relatively displaces the first locking member and the second locking member to locking positions and non-locking positions.

Disclosed are a power transfer device for transferring external power to a rotary body, a pipe cutting device using the power transfer device and a hydraulic chucking device using the power transfer device. The power transfer device is configured to transfer external power to a rotary body coupled to one side of a main body. The power transfer device includes at least one double-action interlocking cylinder mounted to a rear surface of the rotary body and provided with a rod protruding toward the main body, a push unit installed in the main body and provided with at least one pusher protruding toward the rotary body, and a bearing disposed between the pusher of the push unit and the rod of the interlocking cylinder and configured to allow relative rotation of the pusher and the rod and to transfer power between the pusher and the rod.

Disclosed are a power transfer device for transferring external power to a rotary body, a pipe cutting device using the power transfer device and a hydraulic chucking device using the power transfer device. The power transfer device is configured to transfer external power to a rotary body coupled to one side of a main body. The power transfer device includes at least one double-action interlocking cylinder mounted to a rear surface of the rotary body and provided with a rod protruding toward the main body, a push unit installed in the main body and provided with at least one pusher protruding toward the rotary body, and a bearing disposed between the pusher of the push unit and the rod of the interlocking cylinder and configured to allow relative rotation of the pusher and the rod and to transfer power between the pusher and the rod.

The invention relates to a machine (1) for machining pipe ends. At least one centering device (8; 35) is associated to said machine, which centering device centers a tubular workpiece (5, 5) in relation to an axis of rotation (D) of the machine for machining pipe ends extending in the center of the machine, the tubular workpiece either being stationary in the case of a rotating tool head (4) or rotating in the case in which the tubular workpiece is fastened in the machine chuck (9). Precise centering of the tubular workpiece (5, 5) is quickly and simply achieved in that the centering device (8; 35) has a clamping housing (13; 130) that is open toward the axis of rotation (D), which clamping housing is designed comprising at least three means (14, 15, 16; 140, 150, 160) for contacting the tubular workpiece at the outer circumference and for clamping the tubular workpiece (5, 5) in a centered manner, which means are circumferentially distributed and adjust mechanically independently of each other to the particular diameter of the workpiece (5, 5) to be machined.