| 摘要 |
A pilot assembly and method has a cylindrical pilot body with a tapered outer end, a grooved inner end, and a central portion with at least one inwardly curved side wall relief, as well as internally mounted reciprocating ejector pins with outer ends that protrude through holes in the outer body end to strip stock from the pilot. A spring has its outer end mounted in the groove in the outer body end, and an inner end attached to the inner body end in a pre-tensed condition. A cap screw has an enlarged head that has at least a portion thereof fit into the pilot sidewall relief, and a threaded shank that anchors the pilot in an associated die member. |
| 主权项 |
1. In a multi-station progressive metal forming die having at least two mutually converging and diverging die members between which an elongate stock strip is shifted longitudinally to form parts from the stock strip, the improvement of a modular pilot assembly with self-contained stripper, comprising:
a pilot operably supported on one of said die members and having an outer end oriented toward the stock strip, an oppositely disposed inner end oriented away from the stock strip, and a medial portion disposed axially between said outer and inner ends, and including:
a generally cylindrically shaped body portion disposed at said medial portion of said pilot, having a generally closed outer end oriented toward the stock strip, a generally open inner end oriented away from the stock strip, and an outer sidewall with a least one fastener relief therein having an arcuately shaped, radially inwardly curved relief sidewall that extends from said closed outer end to a generally flat arcuately shaped relief end surface facing toward the stock strip and spaced axially a predetermined distance from said open inner end, as well as at least one axially extending ejector pin aperture which opens through said closed outer end and into said open inner end;a generally tapered point portion disposed at said outer end of said pilot, having a circularly shaped innermost collar portion disposed adjacent said closed outer end of said body portion shaped for close reception in a pilot hole in the stock strip, and a generally frusto-conically shaped outer portion configured to engage the pilot hole in the stock strip and guide the same to a predetermined position in an associated die forming station;a generally cylindrically shaped spring retainer rod portion disposed at said inner end of said pilot, having an outer end oriented toward the stock strip, an inner end oriented away from the stock strip, and an outer sidewall with a diameter that is less than the diameter of said outer sidewall of said body portion, thereby forming an annularly shaped spring groove adjacent said outer end of said spring retainer rod portion, as well as a retainer groove disposed adjacent said inner end of said spring retainer rod portion; a spring member having a generally hollow interior that is received onto and over said spring retainer rod portion of said pilot, an outer end oriented toward the stock strip and received in said spring groove, and an opposite inner end oriented away from the stock strip and positioned adjacent to said retainer groove in said spring retainer rod portion; at least one rigid ejector pin slidingly received and retained in said ejector pin aperture in said body portion, having an outer end that protrudes outwardly from said closed outer end of said body portion when urged to an extended condition to contact the stock strip and strip the same away from said pilot, and retracts toward the body portion when urged to a retracted position, and an inner end that operably engages said outer end of said spring member and is thereby biased outwardly by said spring member toward said extended condition; a retainer ring detachably received in said retainer groove in said spring retainer rod portion and engaging said inner end of said spring member in a pre-tensed condition to bias said ejector pin toward said extended condition; and a mounting screw having an enlarged head portion with a circular plan shape that is at least partially, closely received in said fastener relief in said body portion, an annularly shaped inner face oriented away from the stock strip and abuttingly engaging said relief end surface of said fastener relief in said body portion, and a threaded shank portion anchored in said one die member to securely, yet detachably mount said pilot assembly on said one die member in a manner which causes said ejector pin to automatically reciprocate between said retracted and extended positions relative to said body portion of said pilot during operation of said metal forming die to insure that the stock strip is consistently stripped away from said pilot. |
