Abstract: The invention concerns a press for the production of pressed moldings of powdery or granulate materials, as well as a process for controlling the press where a correction of the ram stroke of the press is initiated depending on the association of actual dimensions of the molding with certain tolerance ranges to which different valences have been assigned, and where, depending on the valence in question, no correction, an immediate correction, or a delayed correction of the ram stroke is effected.
Abstract: A prestressed hydraulic press includes a pressure generator for selectively prestressing the hydraulic press such that the press is under substantially constant stress during all phase operations of the hydraulic press.
Abstract: A press with a plurality of injection plungers, which can be used to enclose integrated circuits in plastics packages, is provided with additional compensating pistons. The lower ends of the compensating pistons and the upper ends of the injection plungers project into a filling pot in which the plastics material is molded. The injection plungers force the plastics material in the injection mold through channels into cavities provided in the mold. When a predetermined pressure P.sub.k is exceeded, the compensating pistons retreat, so that a pressure drop and, thus, pressure limitation occur. In this manner, scrap would be avoided even if too large a quantity of plastics material were placed in the filling pot.
Abstract: The invention relates to a pressing apparatus with multi-platen or tiered presses which has a charging basket 1 capable of receiving more tools with material to be pressed than there are tiers in the presses H, K. The capacity of the discharging basket 2 exceeds that of the charging basket 1 by the number of tiers in the tiered presses H, K. The charging basket 1 and the discharging basket 2 are vertically adjustable. The invention makes it possible to stock several tools in the charging basket 1. The tools can then pass through the presses to the discharging basket 2 automatically.