The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 02, 2025
Filed:
Dec. 15, 2023
Danfoss Power Solutions Gmbh & CO Ohg, Neumünster, DE;
Chris Shrive, Bridge of Allan, GB;
Christian Feller, Handewitt, DE;
Matthias Liermann, Neumünster, DE;
DANFOSS POWER SOLUTIONS GMBH & CO. OHG, Neumunster, DE;
Abstract
A hydraulic control circuit for a hydraulic motor operable at least at two displacements, having a proportional speed control valve with a control valve spool continuously moveable by means of a force generated by a pilot pressure being controlled by a continuously, electrically adjustable pilot valve having an electrical actuator, wherein the control valve spool is moveable between a full-torque end position, a reduced-torque end position, and at least one intermediate position. A time related control current function is provided for controlling the current applied to the electrical actuator for controlling the pilot pressure including a pre-current portion with a constant non-zero current and a current ramp portion during which the current is raised or lowered continuously from a ramp starting current level to an intermediate current level. The current is changed abruptly to a switching current level at the end of the current ramp portion for allowing the movement of the speed control valve spool from one of the two end positions via the at least one intermediate switching position into the other end position.