Arrangement for controlling the travel of two hydraulic cylinders
AssigneeMannesmann Rexroth GmbH
InventorTheo Hein
Life of this patent
Estimating the term…
Abstract
For setting and guiding a band running round two rolls the bearings of the roll on either side are each adjustable by a hydraulic or lifting cylinder. Each hydraulic cylinder comprises a position control circuit. The position desired value applied jointly to the position control circuits is varied by a tension-dependent control in such a manner that in the position adjustment a maximum admissible tension force is not exceeded. Furthermore, the position desired value has superimposed thereon a correction control by which the center setting of the band is monitored. The arrangement is preferably provided for positioning and tension-dependent adjustment of the encircling metal band of a sheet casting apparatus.
Claims12
Arrangement for controlling the travel of two hydraulic cylinders which are provided for adjusting the position of different portions of the same component, each cylinder having associated with it a respective directional control valve for connecting the respective hydraulic cylinder to a fluid source or a tank, a position pickup for measuring the travel of the component portion and a position controller for generating an error quantity from the measured position and a desired position signal for driving the directional control valves, characterized in that for each hydraulic cylinder a position controller is provided, and means for supplying to both position controllers the same desired value and a correction value is generated in dependence upon the adjustment of the component as actual value and is added to the desired position signal or subtracted from the desired position signal.
Dependencies are inferred from the claim text.