Patent ID: 8919455

Claim:
A vehicle including: a chassis; a ground engaging mechanism configured to support and propel the chassis; a blade coupled to the chassis; at least one hydraulic angle cylinder coupled to the blade and configured to control angling of the blade right and left; a hydraulic pitch cylinder coupled to the blade and configured to control pitching of the blade forward and backward; and a hydraulic circuit comprising: a hydraulic fluid source; a main control valve positioned downstream of the hydraulic fluid source; a junction positioned downstream of the main control valve; a first flow path between the junction and the at least one hydraulic angle cylinder to provide hydraulic fluid from the junction to the at least one hydraulic angle cylinder; a second flow path between the junction and the hydraulic pitch cylinder to provide hydraulic fluid from the junction to the hydraulic pitch cylinder; and a pitch control valve positioned downstream of the junction along the second flow path, the pitch control valve having a closed configuration that closes the second flow path during angling of the blade and an open configuration that opens the second flow path during pitching of the blade.