Abstract: The invention relates to a hydraulic drive with a plurality of hydraulic consumers also comprising a differential cylinder which are located in particular on a plastics injection-molding machine. There are a first hydraulic machine and a second hydraulic machine, which can both operate as pump and as motor. A first of the two hydraulic machines is connected to a tank by means of a second port and rests against a pressure line by means of a first port, which pressure line can be connected to that working chamber of the differential cylinder which is remote from the piston rod via a shut-off valve. The second hydraulic machine is likewise connected to the pressure line by means of a first port and can be connected, by means of a second port, to a tank via a nonreturn valve which opens toward the second port and to the piston-rod-side working chamber of the differential cylinder via a shut-off valve.

Abstract: A hydraulic circuit for supplying a plurality of series-operated consumers of a hydraulically controlled installation, in particular of an injection molding machine, having a pump with feed-flow pressure control, is described. To be able to slow down greater moving masses with very little expenditure in regard to circuitry and devices, only a portion of the consumers, such as the extruder, the injection unit and possibly the ejector are operated in open circulation, while at least one selected further consumer, such as the clamping unit of the injection molding machine, where a greater mass must be moved in alternating directions, is moved in semi-closed or closed circulation.

Abstract: The present invention relates to a noise dampening assembly of a hydraulic machine and a drive motor, and provides for a structure comprising a block, in which the hydraulic machine is mounted by means of noise dampening elements.

Abstract: In a plastic processing machine (injection moulding machine) the amount of working medium to be supplied to the hydraulic drives and to the injection cylinder and the clamping cylinder is regulated to control the adjustment rates via a quantity control of an adjustment pump. The setting of the pressures necessary at the drives is effected in contrast via a directional valve which controls the fluid paths to one of the drives and which is adapted to be connected to the tank via a regulatable throttle point governing the pressure. This simplifies the apparatus expenditure for the pressure control of such a machine.