Abstract: The invention is aimed at the provision of an automatic releasing-type rolling head for forming a tapered thread on a pipe in which the shock generated at the end of the thread rolling operation is alleviated and a thread automatic rolling roller retracting mechanism is not damaged. The rolling head includes shaft bearing plates 33 which are slidably supported in a plurality of guide grooves 36 radially provided on inner surfaces of the front and rear closures of the housing 30 and which are provided on their outer surfaces in the radial directions with oblique surfaces 33b, thread rolling rollers 35 rotatably supported by the shaft bearing plates 33, a cam ring 31 which rotates in the housing 30 and has cam oblique surfaces 31a opposed to the oblique surfaces 33b of the shaft bearing plates 33, a lever 44 which abuts at its oblique surface against a cam member 45 to prevent movement thereof in association with the cam ring 31 and an abutment member 41 which is pressed and moved by a thread-rolled pipe.

Abstract: A screw cutter die head comprising an annular body portion, a ring member formed with several cam ridges and angularly movable relative thereto and several chasers held by said body member to be radially movable by engagement of a cam recess formed in each chaser with each of said cam ridges is in public knowledge. When it is necessary to process the work of far larger or smaller diameter in the known die head, the chasers must be exchanged with the others formed with the cam recess nearer to the cutting edges or more apart therefrom. The invention provides the chasers formed with a plurality of recesses and the ring member formed with the corresponding number of notches to be engaged with the latch for fixing it.

Abstract: A die-head of a cutting machine having a pair of relatively rotatable annular plates which retractably hold therebetween cutting tools extending in radial directions, one of the plates being provided with a tool retracting lever which is pivotably mounted thereto and which is directly engaged by a projection provided on the other plate, the lever being pivotally moved by a workpiece which extends axially in the plates.

Abstract: A thread-cutting head for pipes, tubes, and the like, with cutting jaws arranged in a cutting-jaw holder. The cutting jaws are radially adjustable by a control disc which is displaceably supported on the cutting-jaw holder and is adjustable by a clamping screw. The control disc for the cutting position of the cutting jaws relative to the cutting jaw holder is adapted to be tensioned and arrested against the force of a spring. The thead-cutting head also has a clamping lever as well as an unlatching abutment projecting into the thread-cutting range. The clamping lever is pivotally journaled on an arresting piece arranged on the control disc about a pivot pin directed transverse to the thread-cutting axis. A catch member is arranged between the cutting-jaw holder and the arresting piece. The clamping lever has a release pin directed against the catch member, and is embodied as an unlatching abutment at that end thereof directed toward the cutting jaw side.

Abstract: A die-head of a cutting machine comprising a pair of relatively rotatable annular plates which movably hold cutting tools therebetween, a tool retracting lever with a stop, pivotally connected to one of the annular plates, a slide integrally connected to the other annular plate and peripherally pressed by a spring, and a pivotable cam plate with a projection bearing against the stop, the slide having a groove into which is engaged the projection of the cam plate, whereby the displacement of the lever, resulting from the movement of a workpiece causes the cam plate to rotate, thus resulting in a rotation of the slide to automatically retract the cutting tools.

Abstract: A die-head of a cutting machine having a pair of relatively rotatable annular plates which retractably hold therebetween cutting tools extending in radial directions, one of the plates being provided with a tool retracting lever which is pivotably mounted thereto and which is engaged by a slide which is slidably arranged on one plate and which tends to rotate together with the other plate by a spring force, the slide being slide to cause relative rotation between the two plates when the lever is pivotally moved by a workpiece which extends axially in the plates.