| 摘要 |
In a strapping head, slitting dies (160;170) on a pair of pivotally mounted sealing jaws (140;146) and a longitudinally movable punch (246) on a punch holder (240) cooperate and are adapted to make a sealless connection in two overlapped layers of a tensioned loop of steel strap. A longitudinally movable sealing yoke (190) pivots the sealing jaws (140;146) by means of cams (230;232) on the sealing yoke (190) and cam followers (180;184) on the sealing jaws (140;146) and moves the punch holder (240) via a connection (196,260,262) allowing lost motion between the sealing yoke (190) and the punch holder (240). A pair of pivotally mounted notching jaws (300;306) and a pair of notching cutters (332;334) on a longitudinally movable notching cutter holder (330) cooperate and are adapted to cut notches in opposite edges of the overlapped layers after the sealless connection has been made. A longitudinally movable notching yoke (320) pivots the notching jaws (300;306) by means of links (370;372) and moves the cutter holder (330) via a connection (350,352) allowing lost motion between the notching yoke (320) and the cutter holder (330). The sealing and notching yokes (190;320) are arranged such that the sealing yoke (190) moves the notching yoke (320) for certain purposes. Strap-cutting means are provided, which are adapted to cut the tensioned loop from the remaining strap. |
