| 摘要 |
<p>A strip of polythene thicker than the material of the hose to be perforated is inserted longitudinally into the hose and the distance between the blades located at two shafts rotating in different directions adjusted in relation to the thickness of the strip. When the electric drive is started the material is moved and perforated at both sides simultaneously. The shafts can be driven with a serrated belt, a v-belt or by a spur gear.</p> |
