Apparatus for separation of waste material from a moulded article

摘要

A method of and apparatus for separating off waste material from a moulded article in the production of hollow articles of thermoplastics material by a blowing process in a multi-part mould involves pinching together regions of a partly-made article during closure of the mould parts around it and once a satisfactory weld seam has been created at the pinch regions then increasing the closure speed of the mould parts. Control of the mould closure speed may be effected by open loop control or by automatic control, and may be made dependent on time and/or on displacement of the mould parts. The increased final closure speed can with advantage be equal to the mould closure speed at which the mould parts are moved up to the beginning of the pinching process.