| 摘要 |
<p>This invention relates to a machine for forming, from round metal blanks, rings with a compressed and toothed inner edge with which to form an outer rim on bimetallic coins or medals. The machine comprises a first punching station in which the round blank is perforated by means of a suitable unit comprising a punch, die and backing die, and a second precoining station in which the inner edge is formed on the perforated round blank by compressing and toothing it by means of a further suitable unit comprising a punch, die and backing die. The pieces to be worked in the stations are fed automatically.</p> |
