Abstract: A flexible tube-bending mandrel has a longitudinally-split shank link that is unthreaded, but recessed to receive a nut that threadedly engages the bolt for holding the link to a mandrel shank. The mandrel center links are longitudinally split for ease of assembly of their ball-and-socket interconnections and have their socket ends externally threaded to receive an internally-threaded ball segment that holds the center link sections in assembled condition and effectively restrains relative longitudinal motion of the two mating link sections.

Abstract: A rotary draw bending machine employs a stack of bending dies 22 of different curvatures, forming part of a bend head 18 that is entirely mounted on the forward end of the machine bed 10 for bi-directional lateral and vertical motion so that without changing the position of the centerline of the pipe 16 to be bent, it may be formed by bend dies of different curvature. The entire bend head 18 is shiftable laterally to enable the bend dies to clear the pipe 16 as the dies move vertically to position another die. A single pressure die 20, which is mounted on the movable bend head 18, is mounted for vertical movement relative to the bend head so that it can be positioned in alignment with the pipe.

Abstract: Material is drawn from a roll of flat stock, passed through a pipe forming machine, and welded to provide a continuous length of pipe which is stored in a variable size loop. Pipe is withdrawn from the loop by means of a series of pipe straightening and feeding rollers which feeds the pipe to a bending machine. The bending machine is suspended from an overhead platform for rotation about a vertical axis and carries a shearing cutter so that multi-bend pipe sections, such as automobile exhaust pipes, may be bent, severed and dropped onto a conveyor for inspection and disposition while the pipe is being continuously formed from the flat stock. Distance between bends and plane of bend are respectively controlled by the pipe feeder and the bend machine rotation. Differences between forming and bending rates are compensated by varying the amount of pipe in the storage loop.

Abstract: A rotary pipe bending machine employs two sets of bending dies for making either right-hand or left-hand bends about a horizontal axis. A pipe handling carriage having a laterally offset chuck is slidably mounted along a track to longitudinally and rotationally position pipe with respect to the machine bending head. The track is pivotally mounted for 180.degree. of rotation about an axis extending longitudinally through the track so that the chuck can be positioned on one side or the other of the longitudinal machine center line. This enables the chuck to position a pipe to be bent by the die set on either side of the machine.

Abstract: A rotary pipe bending machine employs a single hydraulic motor to drive clamp and pressure dies toward the bend die and to rotate the bend and clamp dies. The motor piston is connected via a chain to drive a clamp die carrier toward a rotatably mounted bend die and toward a bend die shaft actuator. Upon continued motion of the clamp die carrier, it engages the actuator to rotate the bend die together with a clamp die mounted on the carrier. The motor cylinder is movably mounted and connected to a pressure die carrier so that as the motor piston drives the clamp die carrier and the bend die, the cylinder, reacting to the driving force of the piston, drives the pressure die carrier, together with a pressure die thereon, toward the bend die with a force that is produced by reaction to the required bending force. Thus the pipe is frictionally tensioned according to the magnitude of the bending force.

Abstract: Material is drawn from a roll of flat stock, passed through a pipe forming machine, and welded to provide a continuous length of pipe which is stored in a variable size loop. Pipe is withdrawn from the loop by means of a series of pipe straightening and feeding rollers which feeds the pipe to a bending machine. The bending machine is suspended from an overhead platform for rotation about a vertical axis and carries a shearing cutter so that multi-bend pipe sections, such as automobile exhaust pipes, may be bent, severed and dropped onto a conveyor for inspection and disposition while the pipe is being continuously formed from the flat stock. Distance between bends and plane of bend are respectively controlled by the pipe feeder and the bend machine rotation. Differences between forming and bending rates are compensated by varying the amount of pipe in the storage loop.

Abstract: A tube bending machine includes a carriage mounting a rotatable chuck for grasping and positioning a length of tube relative to the bending head of the machine. Motion of the carriage along the bed of the machine toward the bending head and rotation of the chuck relative to the carriage are powered by a pair of remotely mounted stationary motors each driving a chain. One chain is connected directly to the carriage and the other engages a sprocket rotatably mounted on the carriage and connected to rotate the chuck. The arrangement provides a differential drive in which the carriage can be driven by operation of both motors and the chuck can be driven by differential operation of the two motors. In addition the chuck can be rotated simultaneously with advance of the carriage.

Abstract: A rotary pipe bending machine employs a single hydraulic motor to drive clamp and pressure dies toward the bend die and to rotate the bend and clamp dies. The motor piston is connected via a chain to drive a clamp die carrier toward a rotatably mounted bend die and toward a bend die shaft actuator. Upon continued motion of the clamp die carrier, it engages the actuator to rotate the bend die together with a clamp die mounted on the carrier. The motor cylinder is movably mounted and connected to a pressure die carrier so that as the motor piston drives the clamp die carrier and the bend die, the cylinder, reacting to the driving force of the piston, drives the pressure die carrier, together with a pressure die thereon, toward the bend die with a force that is produced by reaction to the required bending force. Thus the pipe is frictionally tensioned according to the magnitude of the bending force.

Abstract: For grasping and rotating a tube having a flared end and a rotatable flare fitting thereon a chuck carries a number of pivoted clamps movable radially inwardly against the fitting. An opposing pilot on the chuck enters the end of the tube to axially bear against the inside of the flared end, thereby clamping the rotatable fitting against the tube between the clamps and pilot for a firm grip on the tube end. The clamps and pilot are driven into opposing gripping relation by a slidable chuck housing sleeve which, in turn, is axially driven by a non-rotating thrust block. The housing sleeve, clamps and pilot are all carried for rotation on a driven shaft.

Abstract: In a rotary pipe bending machine in which the pipe is clamped against a rotary bend die by a clamp die and the two dies are rotated together while a rear section of the pipe is pressed by a pressure die, the clamp die is adjustably mounted for motion tangentially of the bend die. The clamp die can be driven between a first position in which it is spaced forwardly of the bend die axis and forwardly of the bend die, and a second position in which it is positioned substantially at a point of tangency between the pipe to be bent and the bend die. The position of the clamp die is chosen according to the length of the straight portion of the pipe between a previous bend and the point at which the next bend is to be made.

Abstract: A tube bend is started by compresssion bending and continued by draw bending. Conventional bending equipment is employed with one die slightly modified so that normal machine operation causes the pressure die to initially operate in a compression bending mode and then to operate in a draw bending mode. The tube is clamped between a rotatable bend and clamp die. The pressure die presses the tube against the bend die and initially moves with the tube so as to exert little axial restraint. The pressure die is caused to exert increasing pressure upon the tube, and its motion with the tube is stopped after a short initial travel, whereupon the pressure die restrains the tube as the bend and clamp dies continue to rotate, thereby to effect a draw bending to the completion of the bend.

Abstract: In a machine for draw bending pipe, a long pressure die that moves with the pipe during the bend is provided with a retractable rear section. Both sections are used for a large degree of bend but when a bend of lesser degree is made near the end of the pipe, interference between the pipe grasping chuck and the long pressure die is avoided by retracting the rear pressure die section.

Abstract: Inspection and verification of configuration of a bent tube is achieved by placing the tube upon a conveyor that moves past a pair of mutually orthogonal optical scanners. Interruptions of a light beam at boundaries of the passing tube are used together with the known beam scan pattern and the known position of the conveyor in the course of its movement to generate signals that define coordinates of vertical and horizontal projections of the tube boundary. From these coordinates the desired tube data can be determined and compared with a reference, thereby comparing tube configuration with a reference configuration.

Abstract: Positioning of a pipe longitudinally and rotationally for each of a number of bends is facilitated by means of a fitting attached to the pipe end and connected with longitudinal and rotational displacement encoders that generate electrical signals. The signals drive a quantitative display of present actual longitudinal and rotational position of the pipe so that no sliding or rotational stops need be employed. One of the encoders is arranged for connection to a fixture which can be used for adjustment of the length of a depth of bend stop rod, employing the same quantitative display.

Abstract: A clamp die for urging a tube against a rotatable bend die is mounted for limited translational and rotational motion so that its tube receiving cavity will accommodate and receive a portion of a bend previously made in the tube. Thus, one bend may be started closely adjacent a previous bend and little or no length of the straight and as yet unbent tube need extend forwardly of the point of tangency with the bend die in order to permit gripping by the floating clamp die.

Abstract: A tube bend is started by compression bending and continued by draw bending. Conventional bending equipment is employed with one die slightly modified so that normal machine operation causes the pressure die to initially operate in a compression bending mode and then to operate in a draw bending mode. The tube is clamped between a rotatable bend and clamp die. The pressure die presses the tube against the bend die and initially moves with the tube so as to exert little axial restraint. The pressure die is caused to exert increasing pressure upon the tube, and its motion with the tube is stopped after a short initial travel, whereupon the pressure die restrains the tube as the bend and clamp dies continue to rotate, thereby to effect a draw bending to the completion of the bend.

Abstract: A tube bending machine includes a carriage mounted rotatable chuck for grasping and positioning a length of tube with respect to the bending head of the machine. Motion of the carriage along the bed of the machine toward the bending head and rotation of the chuck relative to the carriage are both powered by a single remotely mounted motor driving an endless chain. The chain engages a drive sprocket rotatable on the carriage and gear connected to rotate the chuck. A chuck brake and a carriage distance brake are selectively energized so that when chuck rotation is prevented, the sprocket is locked to the chain and the carriage will be driven by the chain, and when carriage travel is prevented, the chuck is rotated by the chain driven sprocket. The remote motor is connected in a primary servo system to provide a closed loop drive of either the chuck rotation or the carriage travel. A closed loop brake control system is provided for each of the chuck rotation and carriage travel.

Abstract: A tube bending machine includes a carriage mounted rotatable chuck for grasping and positioning a length of tube with respect to the bending head of the machine. Motion of the carriage along the bed of the machine toward the bending head and rotation of the chuck relative to the carriage are both powered by a single remotely mounted motor driving an endless chain. The chain engages a drive sprocket rotatable on the carriage and gear connected to rotate the chuck. A chuck brake and a carriage distance brake are selectively energized so that when chuck rotation is prevented, the sprocket is locked to the chain and the carriage will be driven by the chain, and when carriage travel is prevented, the chuck is rotated by the chain driven sprocket. The remote motor is connected in a primary servo system to provide a closed loop drive of either the chuck rotation or the carriage travel. A secondary closed loop brake control system is provided for each of the chuck rotation and carriage travel.

Abstract: Measurement of a vector inn space is accomplished by an articulated five axis probe carrying a working head that can be moved into a measuring position that has a known angular relation to an object to be measured. A plurality of pivotally interconnected links include a first link pivotally mounted to a work table and an end link that fixedly carries a working head having a V-groove defined by four mutually spaced electrically conductive contact elements. For measurements made upon a tube having a number of bends, the working head is successively positioned in contact with the several straight portions of the bent tube and the angles of the several links relative to adjacent links and relative to the work table are read out for each contact. When the working head is properly oriented with respect to the tube, the electrical contacts enable read out of the several angles. These collectively define both the direction of the working head and its coordinate position with respect to a reference coordinate system.