| 摘要 |
<p>A punching machine for sheet metal strip, characterised by comprising: -a base (2), -a horizontal first plate (6) movable vertically under external command, -a punch (20) rigid with saidfirst plate (6) and slidable within a punch guide (18) rigid with a horizontal second plate (16), -means (12, 14) for slidably constraining said second plate (16) relative to said first plate (6), -first elastic means (36) interposed between said first plate (6) and said second plate (16), -a horizontal third plate (24) housed in a seat provided in the base (2), -means (22) enabling said third plate (24) to be moved vertically by said first plate (6), -second elastic means (38) interposed between the lower surface of said third plate (24) and the bottom of the seat (26), said second means having a greater constant of elastic rigidity than the first elastic means, -a die (28) rigid with the base (2) and facing the punch guide (18), -a counter-punch (30) slidable within said die (18), rigid with said movable third plate (24), said die (18) being provided internally with an air jet feed channel (32) and a scrap discharge channel (34), these communicating with the seat of the counter-punch (30), the punchhead (40) having a diameter less than the diameter of its seat in the punch guide (18), said seat being of smaller diameter than the counter-punch (30), the counter-punch (30) being provided at that end facing the punch (20) with a frusto-conical portion (46), the major base of which has a diameter less than the diameter of the punch seat and the minor base of which has a diameter greater than the diameter of the punch head (40).</p> |
