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:
May. 07, 2013
Filed:
Jan. 06, 2012
Satoru Shintani, Hirakata, JP;
Tomohiro Nakagawa, Hirakata, JP;
Ryouichi Nagasaka, Fujisawa, JP;
Komatsu Ltd., Tokyo, JP;
Abstract
A control device for automatically controlling a pitch angle of a blade includes a hydraulic oil amount calculation unit and an open ratio setting unit. The hydraulic oil amount calculation unit is configured to calculate an amount of hydraulic oil passing through a blade tilt cylinder valve. The open ratio setting unit is configured to cause the blade tilt cylinder valve to open at a predetermined open ratio when a request for the pitch angle to be changed has been received, to cause the blade tilt cylinder valve to close when the calculated amount of hydraulic oil has reached a predetermined amount of hydraulic oil required for the change of the tilt angle, and to cause the open ratio to be smaller than the predetermined open ratio while a request for a predetermined action necessitating that hydraulic oil be supplied from a main valve is being received.