A hydraulic system consists of two parts: signal control and hydraulic power. The signal control part drives the control valves in the hydraulic power part.
The hydraulic power part is represented using a circuit diagram to show the interrelationships between different functional components. The hydraulic power source includes a hydraulic pump, an electric motor, and hydraulic auxiliary components; the hydraulic control part contains various control valves used to control the flow, pressure, and direction of the working fluid; the actuator part contains hydraulic cylinders or hydraulic motors, which can be selected according to actual requirements.
When analyzing and designing practical tasks, a block diagram is generally used to show the actual operating status of the equipment. Hollow arrows represent signal flow, while solid arrows represent energy flow. The sequence of actions in a basic hydraulic circuit includes: the reversing and spring reset of the control element (two-position four-way directional valve), the extension and retraction of the actuator (double-acting hydraulic cylinder), and the opening and closing of the relief valve.
