Steel strap welding apparatus for use in an automatic strapping machine

Claim 1

A steel strap welding apparatus for welding overlapped ends of a steel strap emanating from a supply and passing about a package or the like comprising in combination a welding, clamping, and cutting head positioned directly above an overlapped strap to be welded, said head including three stations spaced longitudinally along the overlapped strap ends, a. said first station defining a welding chamber and including a support electrode located below said strap ends and mounted on a pivot axis which is above and in vertical alignment with the support electrode means to move said support electrode in and out of position beneath said axis and overlying strap ends, pressure electrode mounted above said overlapped strap ends and opposite said support electrode, means to move said pressure electrode against said strap ends to thereby tightly engage said strap ends with said support electrode, and means for applying electrical power to said electrodes, b. said second station defining a clamping chamber and including a pair of pivotally mounted clamp members beneath said overlapped strap ends, and link means connected to said clamp members and to said means to move said support electrode, whereby when said support electrode is moved into welding position beneath said overlapped strap ends, said clamp members are simultaneously moved into strap clamping position, and c. said third station defining a strap cutting chamber and located between said second chamber and said strap supply and including a fixed blade between said overlapped straps and a shearing blade located above said straps, and power means to move said shearing blade against the strap end to be severed.