发明名称 Apparatus for making a transition plate for a mine roof truss
摘要 Apparatus and method for making a transition plate for a mine roof truss from a strip of metal includes a die set having a first and second station. In the first station the strip of metal is bent downwardly at its sides, a notch is sheared in both sides of the strip and two holes are pierced through the strip. In the second station the transition plate is completed by bending the leading portion of the strip into an "M" shaped saddle portion, the strip is sheared transversely and bent downwardly at its trailing end.
申请公布号 US4429560(A) 申请公布日期 1984.02.07
申请号 US19810323322 申请日期 1981.11.19
申请人 BETHLEHEM STEEL CORPORATION 发明人 SCHAEFFER, CHARLES W.
分类号 B21D28/26;B21D35/00;(IPC1-7):B21D28/14 主分类号 B21D28/26
代理机构 代理人
主权项
地址