| 摘要 |
<p>A web cut-off device, which comprises a piston chamber (13) and a piston (12) fitted as moving in the piston chamber (13), to which piston a cutter blade (11) is attached. The lower part of the piston chamber (13) communicates with pressure chambers (30, 31) through lower connecting ducts (32, 33), and the upper part of the piston chamber (13) communicates with return pressure ducts (60, 61) through upper connecting ducts (62, 63). Further, piston (12) stop cushions (17, 18) are placed in the top portion of the piston chamber (13), and bottom connecting ducts (16) opening to the bottom of the piston chamber (13) below the piston (12) are placed at the bottom of the piston chamber (13). The lower connecting ducts (32, 33) passing from the pressure chambers (30, 31) into the piston chamber (13) open directly into the side walls (14, 15) of the piston chamber (13) at the level of the bottom face of the piston chamber (13), in which case the piston (12) also operates as a valve between the piston chamber (13) and the pressure chamber/chambers (30, 31).</p> |
