Method for controlling a hydraulic unit in particular for a drivetrain of a motor vehicle, hydraulic unit and drivetrain with hydraulic unit
AssigneeSchaeffler Technologies AG & Co. KG
InventorsRalf Mannsperger, Timo Enders
Life of this patent
Estimating the term…
Abstract
A method for controlling a hydraulic unit with a rotational-speed-controlled pump, which, at an outlet side, provides at least two fluid flows in a manner switched by means of switching valves, for actuating at least one slave cylinder and for providing a volume flow which is controlled based on a rotational speed of the pump. To set the volume flow, an efficiency of the pump is calculated based on a comparison of a known slave cylinder volume of the at least one slave cylinder and a quantity of fluid of the pump for the filling of the at least one slave cylinder.
Claims16
A method for controlling a hydraulic unit, comprising:
- switching, via a switching valve, between at least two fluid flows at an outlet side of a rotational-speed-controlled pump, wherein one of the fluid flows actuates at least one slave cylinder and the other of the fluid flows provides a volume flow, which is controlled based on a rotational speed of the pump, and
- calculating an efficiency of the pump based on a comparison of a known slave cylinder volume of the at least one slave cylinder and a quantity of fluid of the pump for the filling the at least one slave cylinder.
A hydraulic unit comprising a pump, at least one slave cylinder, a switching valve and a control device, wherein the control device is programmed to:
- switch, via a switching valve, between at least to fluid flows at an outlet side of the pump,
- determine a quantity of fluid of the pump for filling the at least one slave cylinder based on a fluid flow for actuating the slave cylinder;
- and
- calculate an efficiency of the pump based on comparing a known slave cylinder volume of the at least one slave cylinder and the quantity of fluid.
A drivetrain, comprising a drive unit, a transmission, a separating clutch arranged between the drive unit and the transmission, a parking lock, and a hydraulic unit including a pump, at least two slave cylinders, a switching valve, and a control device, wherein one slave cylinder is engaged with the separating clutch and another slave cylinder is engaged with the parking lock, wherein the control device is programmed to:
- selectively actuate the separating clutch or the parking lock via the switching valve;
- determine a quantity of fluid of the pump for filling the slave cylinder engaged with the actuated one of the parking lock or separating clutch based on a fluid flow for actuating the respective slave cylinder;
- and
- calculate an efficiency of the pump based on comparing of a known slave cylinder volume of the respective slave cylinder and the quantity of fluid.
Dependencies are inferred from the claim text.