A system is described comprising an actuator with a piston linearly movable and a needle shutter connected to the piston for regulating the injection flow of molten material from a nozzle into a mold. By a supply circuit pressurized fluid is brought to the piston to move it back and forth. A solenoid valve is connected to the supply circuit and configured so that in resting condition it leaves open a fluid drainage path for bringing the shutter to a closing position.

A hydraulic system for a cyclically operating shaping machine includes at least one hydraulic drive unit for cyclically driving a component of the shaping machine at a start time; at least one pump; and at least one hydraulic accumulator which can be discharged for driving the at least one hydraulic drive unit and which can be charged up by operation of the at least one pump. An open-loop or closed-loop control unit is also provided for control of the at least one pump. The open-loop or closed-loop control unit is adapted to operate the at least one pump continuously until the start time of the at least one hydraulic drive unit to charge up the at least one hydraulic accumulator until the start time of the hydraulic drive unit.

A hydraulic system for a cyclically operating shaping machine includes at least one hydraulic drive unit for cyclically driving a component of the shaping machine at a start time; at least one pump; and at least one hydraulic accumulator which can be discharged for driving the at least one hydraulic drive unit and which can be charged up by operation of the at least one pump. An open-loop or closed-loop control unit is also provided for control of the at least one pump. The open-loop or closed-loop control unit is adapted to operate the at least one pump continuously until the start time of the at least one hydraulic drive unit to charge up the at least one hydraulic accumulator until the start time of the hydraulic drive unit.

A hydraulic system for a molding machine with a hydraulic valve, includes an actuator for positioning the hydraulic valve, a machine control system realized separate from the hydraulic valve, a first signal connection between the machine control system and the hydraulic valve, and a sensor. The sensor is signal-connected to the machine control system via a second signal connection, and the machine control system is formed to carry out a valve regulation of the hydraulic valve on the basis of measured values of the sensor.

A hydraulic system for a molding machine with a hydraulic valve, includes an actuator for positioning the hydraulic valve, a machine control system realized separate from the hydraulic valve, a first signal connection between the machine control system and the hydraulic valve, and a sensor. The sensor is signal-connected to the machine control system via a second signal connection, and the machine control system is formed to carry out a valve regulation of the hydraulic valve on the basis of measured values of the sensor.

The invention relates to a resin injection regulator for a resin injection circuit in a mould for producing a composite part, in particular a turbine engine composite part, characterised in that it comprises at least one vessel which is connected to said circuit and inside of which a movable wall means can be moved in a sealed manner, said movable wall means defining in said vessel a first cavity which forms a container for accumulation of resin and is designed to be connected to at least one part of said circuit, and a second cavity which is designed to be connected to a source of pressurised fluid, said movable wall means being designed to be urged by the pressurised fluid with which the second cavity is supplied in order to exert a pressure on the resin contained in the first cavity by isolating said resin from said fluid.

The invention relates to a resin injection regulator for a resin injection circuit in a mould for producing a composite part, in particular a turbine engine composite part, characterised in that it comprises at least one vessel which is connected to said circuit and inside of which a movable wall means can be moved in a sealed manner, said movable wall means defining in said vessel a first cavity which forms a container for accumulation of resin and is designed to be connected to at least one part of said circuit, and a second cavity which is designed to be connected to a source of pressurised fluid, said movable wall means being designed to be urged by the pressurised fluid with which the second cavity is supplied in order to exert a pressure on the resin contained in the first cavity by isolating said resin from said fluid.

A roll stack for the production of plastic sheeting uses a pneumatically-operated toggle joint, instead of a hydraulic press, to precisely separate two rollers. The pneumatically-operated toggle joint allows the rollers to be more quickly and safely further separated from each other in case there is an emergency.

A roll stack for the production of plastic sheeting uses a pneumatically-operated toggle joint, instead of a hydraulic press, to precisely separate two rollers. The pneumatically-operated toggle joint allows the rollers to be more quickly and safely further separated from each other in case there is an emergency.

A digital pump axis control system having a circuit including an electric engine, powering first and second hydraulic machines connected in a rotationally locked manner to each other. At least one cylinder has a first chamber connected through a first pipeline to the first hydraulic machine and a second chamber of the cylinder is connected through a second pipeline to the second hydraulic machine. A first valve is arranged in the first pipeline; a second valve is arranged in the second pipeline; a third valve is arranged in a third pipeline, wherein the third pipeline connects a portion of the first pipeline between the first hydraulic machine and the first valve and a portion of the second pipeline between the second hydraulic machine and the second valve. An open tank provides hydraulic fluid to inlets of the first and second hydraulic machines. The first and second hydraulic machines are digital variable displacement pumps, each providing a positive and a negative displacement of hydraulic fluid.