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US 5,845,493 AGranted
Method and apparatus for operating a hydraulic drive
AssigneeDr. Boy GmbH
InventorAlfred Schiffer
Life of this patent
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AssigneeDr. Boy GmbH
InventorAlfred Schiffer
Estimating the term…
The drive includes a reversible variable output pump (1), which supplies a hydraulic working machine (6) and is driven by an asynchronous motor (2). The working machine is intermittently hydraulically pressurized. During these times the asynchronous motor can be switched off since the subsequent start-up process, which causes a high current consumption in the case of asynchronous motors, is effected by the variable output pump. Before the beginning of the start-up process the variable output pump is preset to the maximum negative discharge rate by its proportional valve (10) being acted on by a control pressure. The volume pressurized in the working machine is then applied to the output side of the variable output pump. The asynchronous motor is connected to the current supply network after reaching a minimum speed.
Method of operating a hydraulic drive which drives at least one hydraulic working machine, the drive including at least one reversible variable output pump, which is connected to the hydraulic working machine, and an asynchronous electric motor, which is connected to a current supply network and drives the variable output pump, the method including the following steps:
In a hydraulic drive including
Dependencies are inferred from the claim text.