US 4,493,202 AGranted

Railroad spike forging machine

AssigneeStafford Rail Products, Inc.

InventorRichard J. Stafford

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Abstract

In a railroad spike forging machine of the type comprising a steel stock pointing roller assembly which longitudinally feeds pointed spike blanks along a centerline to a head forming station, a main die of hardened tool steel having a die zone defined between its leading edge and an intermediate point of said first longitudinal dimension, and a wipe zone defined between said intermediate point and the trailing edge of the die by a transversely extending entrance wall surface to the die zone, whereby a transverse wiping of the channel is enabled in said wipe zone. Further, a sensing means generates position signals from the rotation of a pointer roller, and a spike positioning mechanism comprises a first hydraulic cylinder operable transversely to extend a stop mechanism in response to a first position signal, thereby to stop forward motion of a spike blank at an appropriate distance downstream of the die leading edge. A spike ejection mechanism comprises a second hydraulic cylinder operable transversely to extend a side wiping assembly across the wipe zone in response to a second position signal.

Claims6

Dependent claims

In a railroad spike forging machine of the type comprising a steel stock pointing roller assembly which longitudinally feeds pointed spike blanks along a centerline to a head forming station, where a gripper arm holds the blank in a main die as a heading die contacts and expands an unsupported leading edge of the spike blank against a recess in the leading edge of the main die, thereby to shape a spike head, the improvement which comprises;

a main die of hardened tool steel having a first vertical dimension, a first transverse dimension and a first longitudinal dimension between its leading edge and a trailing edge, wherein a die zone is defined between said leading edge and an intermediate point of said first longitudinal dimension, said die zone comprising an upwardly open and longitudinally extending channel, having a second transverse dimension and a second vertical dimension, wherein further a transversely open wipe zone is defined between said intermediate point and the trailing edge of the die by a transversely extending wall surface which further comprises a symmetrical entrance to the die zone, at said intermediate point and a longitudinally and transversely extending channel entrance surface, said die surfaces together defining an open transverse relief for the channel, whereby a transverse wiping of the channel is enabled across said entire wipe zone of the die.

Dependencies are inferred from the claim text.