Hydraulic system

A hydraulic system comprising:

• at least one circulation pump assembly provided with a speed controller;
• at least one hydraulic circuit connected to the circulation pump assembly;
• at least one mechanical switch device which is subjected to pressure from a fluid in the hydraulic circuit and which can be moved into at least two different switch positions, wherein the at least one mechanical switch device can be moved by the circulation pump assembly by way of a hydraulic coupling via the fluid, and the speed controller is configured to initiate a movement of the switch device by way of at least one hydraulic force acting upon the switch device and causing a movement of the switch device via the hydraulic circuit, via a speed adaptation of the circulation pump assembly;
• another hydraulic circuit wherein the circulation pump assembly is connected to at least two hydraulic circuits and the at least one mechanical switch device is configured as at least one valve with at least two movable valve elements for changing a ratio of flows through the at least two hydraulic circuits, the at least one valve comprising at least one first and a second control surface, upon which a fluid pressure produced by the circulation pump assembly acts, wherein the first control surface is connected to the first valve element and the second control surface is connected to the second valve element such that the valve elements are movable by way of the forces acting upon the first and second control surface, the two valve elements having different dynamic characteristics such that the valve elements react differently to different pressure changes in the system.