Pressure generating device and operating method comprising an electrically driven dual-action reciprocating piston

A method for the optional pressure build-up and pressure reduction in first and second hydraulic circuits to which at least two hydraulic chambers of one or more consumers are connected,

• with a pressure generating device which comprises a piston-cylinder unit that has a bilaterally acting piston, which separates first and second working spaces in the cylinder from one another in a sealing manner, and a drive configured to drive the piston of the piston-cylinder unit,
• wherein the drive has a linear actuator in the form of a linear motor or rotation motor and gear mechanism,
• wherein the piston has two effective surfaces and each effective surface of the piston respectively defines a working space of the first and second working spaces, wherein the pressure generating device is adapted to build up and reduce pressure by driving the linear actuator by a predetermined pressure rod path which is calculated taking into account the effective surface in a backward or forward stroke,
• wherein each of the first and second working spaces is connected via a hydraulic line to a respective hydraulic circuit,
• wherein at least one hydraulic chamber of a consumer is connected to respective ones of the first and second hydraulic circuits,
• wherein pressure build-up in one hydraulic chamber of a consumer associated with one hydraulic circuit is carried out by a forward stroke or return stroke of the piston via a working space,
• wherein both working spaces are switchable hydraulically connected with a reservoir, the method comprising:
• performing pressure reduction in one or both hydraulic circuits separately or at the same time, in a way that either:
• a) the pressure reduction in the first hydraulic circuit takes place by a return stroke of the piston which enlarges the first working space, wherein hydraulic fluid from the second working space is released through a hydraulic connection and a corresponding opened valve into the reservoir and/or the pressure reduction in the first hydraulic circuit is done via the first working space and the hydraulic line and the corresponding opened valve into the reservoir;
• or
• b) the pressure reduction in the second hydraulic circuit takes place by a forward stroke of the piston which enlarges the second working space, wherein hydraulic fluid from the first working space is released through a hydraulic connection and a corresponding opened valve into the reservoir and/or the pressure reduction in the second hydraulic circuit is done via the second working space and the hydraulic line and the corresponding opened valve into the reservoir.