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:
Apr. 06, 2010
Filed:
Feb. 07, 2007
Brian Nielsen, Viborg, DK;
Brian Nielsen, Viborg, DK;
Sauer-Danfoss ApS, Nordborg, DK;
Abstract
A hydraulic actuator for a hydraulic servomotoris disclosed. The hydraulic servomotorhas a first chamberand a second chamberassociated therewith. The hydraulic actuator is connected to a fluid sourceand a fluid drain, and it comprises a valve assembly arranged between the fluid sourceand the fluid drainto control fluid pressures in the chambers. At least one auxiliary valveis fluidly connected between the valve assembly and the fluid drain, said auxiliary valve(s)being of a kind which is normally closed in a de-energized state. In the case of a power cut off the auxiliary valve(s)will close, thereby preventing fluid flow from the valve assembly towards the fluid drain. This causes a servomotor piston memberto be hydraulically locked in its instantaneous position, thereby locking the hydraulic servomotor. The valve assembly may be designed without taking the locking function into consideration.