Variation of central hydraulic oil supply (system with impressed pressure), in which a hydraulic accumulator performs the task of providing energy at power peaks. This can be used to select the flow rate Q 1 of the pump according to the average consumption V N during a working cycle t S:
(accumulator consumption diagram). Multiple consumers can be operated simultaneously from the pressure network with a sufficiently constant pressure and without a reaction.
The disadvantage is the power loss, which results when the load pressure p L and accumulator pressure p Sp are not the same size and throttle or pressure-reducing valves have to be used (storage losses).
Accumulator drives are equipped with constant pumps or variable pumps with a pressure controller. They become more cost-effective as more consumers are supplied, as the removal time decreases and the consumption of the individual consumers becomes more different.
Hydraulic accumulators are to be designed in accordance with DIN 24 552 with a pressure measuring device, safety device to protect against overpressure (safety valve) and with a shut-off device. These devices are normally grouped in an accumulator safety block (Figure S 66).