| 摘要 |
<p>A device for forming a hole with a rounded edge. The device has a punch ( 1) having a rounded shape (5) formed at the base of its foremost end (2) and also has a die (8) for supporting the peripheral edge of a punched hole (4) by a pressure receiving surface (9) normal to the axis of the punch, where the punched hole (4) is formed by being punched by the foremost end (2) of t he punch (1). In one stroke of the punch (1), a workpiece (3) is punched by the foremost end (2) of the punch (1) to form the punched hole (4) and, at t he same time, the rounded shape (5) of the foremost end (2) is transferred t o that ridge (6) at the punched hole (4) that is on the aesthetically-design ed surface (3a) side. A hole with a rounded edge can be efficiently formed, and because the peripheral edge of the punched hole (4) is supported by the pressure receiving surface (9), a uniform and highly accurate rounded shape (7) can be added to the ridge (6) of the punched hole (4).</p> |
