Tool for the production of undivided cores or molds of sand for casting parts, which have a thread

摘要

In tools of this kind with a thread-forming pattern (3) which can be inserted into a core box or flask, there is the problem of unscrewing the pattern (3) without damaging the moulding material. To ensure that the thread reproduced in the finished core or finished mould remains largely free from forces when the thread-forming pattern (3) is unscrewed, the pattern (3) has an external thread (4) and an internal thread (6) of the same pitch, the non-thread-forming thread being guided on a threaded spigot (2) or in a threaded nut, which absorbs the forces which occur during unscrewing. IMAGE