Abstract: An injection molding machine, comprises, an injection piston which is hydraulically actuated during programmed injection and dwell pressure phases. During a speed-controlled injection phase I, the pressure in a tool or mold cavity is measured and monitored. As soon as the pressure reaches an initial desired value, a pressure surge-free switching to the dwell pressure phase II is effected. During the dwell pressure phase, the pressure in the tool cavity is controlled and a pressure in a hydraulic cylinder for moving the injection piston is measured and monitored. A switch signal is produced from the tool pressure and the hydraulic pressure, by means of which a switching to a solidification phase III is effected without causing pressure surges. The actual pressure value at the instant of switching serves as the initial desired value for the solidification phase III. The hydraulic pressure is controlled during this phase.

Abstract: An injection mold with locking device comprises a fixed backing plate and a fixed mold part plate which are connected to each other by four tie rods. A movable mold part plate is connected to the fixed backing plate through a drive and locking mechanism which is capable of moving the movable mold part plate into a mold position with the fixed mold part plate. A thermal force control apparatus is associated with one or more of the tie rods for changing the temperature of the tie rods and thereby causing the tie rods either to expand or contract. By such expansion or contraction, the exact force applied between the fixed and movable mold part plates can be adjusted to a desired level.

Abstract: In a melting and conveying device for a plastic injection molding machine, having a melting cylinder with a cylindrical bore therein and a worm member in said cylindrical bore, a degasser, comprising, a vent pin extending into the melting cylinder in a degassing zone of the cylinder bore. The vent pin defines a widened charging pocket which communicates with the cylindrical bore and has a vent opening therethrough communicating the pocket to the atmosphere. A pair of heating elements extend into suitably provided openings in the vent pin to selectively heat the vent opening and pocket independently of any heating elements of the plastic injection molding machine to prevent clogging of the pocket and vent opening by solidified plastic material.

Abstract: A working machine, particularly an injection-molding machine includes two separable mold parts which are closed together in at least one direction and an injection device for the mold which produce inertial forces and which are mounted for movement on a fixed support in at least one direction. The device includes an actuator also mounted on the support having a movable actuator part connected to the machine part which is displaceable in the direction of the inertial force.

Abstract: A tool carrier mechanism for injection molding machines for securing a tool part to a tool carrier, comprises a guide bolt having means for connecting it to the tool part so that it projects outwardly from the rear of the tool part. A tool carrier has a bore therethrough for receiving the guide bolt and has a front face against which the rear of the tool part is engageable and has an opposite rear face beyond which said guide bolt projects. A slide mounted on the tool carrier adjacent the rear face of the tool carrier is movable toward and away from the guide bolt for engagement and disengagement therefrom. Wedge surfaces are defined between the guide bolt and said slide effecting an inward movement of the guide bolt with the tool part to exert an inward pressure engagement of the tool part with the tool carrier.

Abstract: A plasticizing device for an injection molding machine for plastics comprises a screw housing having a cylindrical plastic material chamber at one end having a discharge opening. A cylindrical screw is rotatably and axially displaceably mounted in the housing and has a screw head portion adjacent the discharge with an intermediate body portion of reduced diameter adjacent the head portion and a uniform diameter portion on the opposite side of the intermediate portion from the head portion. The uniform diameter portion carries a spiral screw thread which projects radially outwardly from the surface of the screw. A seal ring having an outer periphery engaged with the interior of said screw housing and having an interior diameter greater than and spaced radially outwardly from the intermediate portion of the screw defines a plasticizing material passage with the intermediate portion which connects through a passage defined between a seal washer on the screw which cooperates with the seal ring.

Abstract: A feeding screw assembly of a molding machine for plasticizable masses, particularly, plastics and rubber, comprises a passage part of the screw which has a passage therethrough having mixing means therein for intermixing a plasticizable material which passes through the passage. The material is diverted into the mixing passage which extends completely through the length of the mixing part by communicating passages located upstream for the inflow of the material and downstream for the discharge of the material after it is mixed. The construction may also include a passage portion which comprises an annular displaceable part having an end or side bounding a communicating passage upstream and which will move in a direction to close off this passage after a part of the other material has been fed into the mixing passage.