| 摘要 |
<p>The machines consist of punches struck by hammers or connecting rods operated by eccentrics, which cut the holes in the material; a central anvil; a support which carries the rivetting nozzles; a transporter operated by eccentrics and connecting rods, consisting of two presser feet, one for up and the other for down, which press the material against a rigid central support that advances jointly with the presser feet; and a depth stop for the material.</p> |
