| 摘要 |
<p>Moulds for casting metal shields for therapeutic ionising irradiation are produced by cutting out plastic plate using an electrically-heated wire. The latter is fixed in position at the top end and moved in two dimensions at the bottom, so that an illustration of the periphery of the item to be protected can be followed, cutting out the plastic plate which is secured between the wire ends. The bottom end of the wire is mechanically moved and controlled by an electrically-controlled x-y plotter. The latter receives signals from a computer for movement on the x- and/or y-axis, and these signals are derived from an illustration on a monitoring screen of the shape of the plastic plate to be cut out.</p> |
