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:
Mar. 27, 2018
Filed:
Nov. 28, 2012
Vestas Wind Systems A/s, Aarhus N., DK;
Jakob Hviid Nielsen, Tjele, DK;
Soren Kjaer Nielsen, Aalborg, DK;
Ole Mølgaard Jeppesen, Skjern, DK;
Jesper Lykkegaard Neubauer, Hornslet, DK;
Vestas Wind Systems A/S, Aarhus N., DK;
Abstract
The present invention relates to a hydraulic pitch system for pitching a blade of a wind turbine having a hub by means of a hydraulic fluid. The system comprises at least one hydraulic cylinder for adjusting a pitch angle of the blade, the hydraulic cylinder comprising a pitch piston movable in the hydraulic cylinder, and a first port and a second port arranged on each side of the pitch piston, and an accumulator hydraulically connected to the cylinder. The system further comprises a pitch safety system adapted to maintain the blade in a predetermined pitch angle when a person is entering the hub of the wind turbine for service and/or maintenance, the pitch safety system comprising a first valve which by activation releases a pressure in the hydraulic pitch system by draining off the accumulator for the hydraulic fluid until the pressure has reached a predetermined pressure level.