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AssigneesArtemis Intelligent Power Limited, Sauer-Danfoss ApS
InventorsUwe Bernhard Pascal Stein, Niall James Caldwell
Estimating the term…
A fluid working machine comprises a controller (12) and a working chamber (2) of cyclically varying volume. The working, chamber has both an electronically controllable primary low pressure valve (14) and a secondary low pressure port (22) associated therewith, each of which is openable and closable in phased relation to cycles of working chamber volume to bring the working chamber into fluid communication with a low pressure manifold (16, 26). At least the primary low pressure valve is under the active control of the controller to enable the controller to determine the net displacement of fluid by the working chamber on a cycle by cycle basis. The primary low pressure valve and the secondary low pressure port are openable concurrently during a portion of at least some cycles of working chamber volume to enable fluid to flow into or out of the working chamber concurrently through both the primary low pressure valve and the secondary low pressure port. The primary low pressure valve may be closed under the active control of the controller a period of time after the secondary low pressure port closes.
A fluid working machine comprising a controller and a working chamber of cyclically varying volume, the working chamber having an electronically controllable primary low pressure valve associated therewith to control the connection of the working chamber to a low pressure manifold, the controller being operable to actively control at least the primary low pressure valve, in phased relationship to cycles of working chamber volume, to determine the net displacement of fluid by the working chamber on a cycle by cycle basis, characterised in that the working chamber further comprises a secondary low pressure port which is openable and closable in phased relationship to cycles of working chamber volume to connect the working chamber to a low pressure manifold, to enable fluid to flow into or out of the working chamber concurrently through both the primary low pressure valve and the secondary low pressure port during a portion of at least some cycles of working chamber volume.
A method of supplying fluid to or receiving fluid from a fluid working machine working chamber of cyclically varying volume, during an intake or discharge stroke of the working chamber respectively, comprising opening an electronically controllable primary low pressure valve, in phased relation to cycles of working chamber volume, to bring the working chamber into fluid communication with a low pressure manifold under the active control of a controller on a cycle by cycle basis, characterised in that the method further comprises opening a secondary low pressure port, in phased relation to cycles of working chamber volume, to bring the working chamber into fluid communication with a low pressure manifold by a second path, such that, during a portion of at least some cycles of working chamber volume, the primary low pressure valve and secondary low pressure port are open concurrently such that fluid flows into or out of the working chamber, as appropriate, through both the primary low pressure valve and the secondary low pressure port.
Dependencies are inferred from the claim text.