Moulding ceramic tiles contg undercuts - where forming tools for undercuts are mounted on knife-box used to trim the tile

摘要

Mfr. of ceramic mouldings contg. an undercut, esp. roof tiles or facade panels, using a two-part die for pressing the tile after which the mould is opened and the lower die-half moved to a de-burring station provided with a knife-box and a tool to make the undercut, as in Parent Patent, is improved in that the moulding is first de-burred and the undercut formed while the knife-box is still lowered and the die closed in the region where the undercut is to be formed. Pref. the undercut forming tool is coupled to the knife-box and protected against a static electrical charge, i.e. to prevent the tool picking up the ceramic moulding material. Used for mfr. e.g. of interlocking tiles. Prevents distortion of the soft tile while the undercut is being formed.