Impact cutoff
AssigneeThe National Machinery Company
InventorAaron T. Hall
Life of this patent
Estimating the term…
Abstract
An impact cutoff device for a progressive high speed cold former having a low mass rigid cutter carriage, a torsion spring for carriage return, and an articulated, oil lubricated and dampened carriage drive block on a pivoting drive lever serving to reduce impact induced vibration otherwise leading to fatigue failure and wear of the various cutter parts and consequent loss of cutoff accuracy and quality.
Claims6
An impact cutter assembly for shearing blanks from wire stock comprising stationary and movable cutter blades, the movable cutter blade being mounted in a carriage that reciprocates along a line between a wire receiving position where the blades are aligned and a delivery position where the blades are displaced from one another, a striker block having a flat surface perpendicular to the line of carriage reciprocation, the carriage having a flat surface, said striker surface and carriage surface being perpendicular to the line of carriage reciprocation and parallel to one another, a driver for moving the striker surface towards the carriage surface at a velocity of at least 1.5 meters per second, and a lubrication oil circuit for directing lubrication oil to a space between the striker and carriage surfaces whereby an impact between a moving striker surface and a stationary carriage surface is damped by the presence of a film lubricating oil.
An impact cutter for cutting wire stock into blanks for a high speed cold forming machine, the cutter having a fixed and a movable cutter, the moveable cutter being carried on a moveable carriage, a driver for forcibly moving the carriage from a start position where the cutters are aligned to accept wire therebetween and a delivery position where a blank in the moveable cutter cut from the wire supply is located for transfer, the driver having a first position spaced from the carriage when the carriage is in the start position, a second position where it first engages the carriage in the start position, and a third position in engagement with the carriage when the carriage is at the delivery position, and a torsion spring biasing the carriage against the driver when the driver is between said second and third positions.
An impact cutter comprising a cam rotatably driven about an axis, a pivotal drive lever, and a cam follower rotatably mounted on the lever and causing the lever to pivot in response to a profile of the cam, the cam follower and lever being rotatable and pivotable about respective axii parallel to the cam axis, a cutter carriage movable in translation along a line between a wire receiving position and a blank delivery position, a drive block carried by and pivotal on the drive lever about an axis parallel to the cam axis, the drive block having an impact surface engageable with said cutter carriage, the drive block being resiliently biased about the drive block axis against a stop surface on the drive lever, the drive block being against the stop surface and the impact surface being perpendicular to the line of motion of the cutter carriage at a position of the drive lever where the impact surface first engages the cutter carriage, pivotal motion of the drive block enabling the impact surface to remain perpendicular to the line of movement of the cutter carriage during translational movement of the cutter carriage between the wire receiving position and the blank delivery position.
Dependencies are inferred from the claim text.