Patent ID: 8548691
Filing Date: 2013-10-01
Classification: E02F

Abstract:
1. A blade control system, comprising: a lift frame vertically pivotably attached to a vehicle body; a blade attached to a tip of the lift frame; a lift cylinder configured to vertically drive the lift frame; a control valve configured to supply a hydraulic oil to the lift cylinder; a blade angle calculating part configured to calculate a blade angle which is sum of a forwardly inclined angle of the vehicle body with respect to a reference surface and a blade lifting angle of the lift frame with respect to a reference position; a slope angle obtaining part configured to calculate a slope angle of a designed surface with respect to the reference surface, the designed surface indicating a target contour of an object for dozing; a difference angle calculating part configured to calculate a difference angle between the blade angle and the slope angle; a first open ratio setting part configured to set a first open ratio of the control valve based on the difference angle; a blade load obtaining part configured to obtain a blade load acting on the blade; a difference load calculating part configured to calculate a difference load between the blade load and a target blade load; a second open ratio setting part configured to set a second open ratio of the control valve based on the difference load; and a lift controlling part configured to control the control valve based on the second open ratio when the blade load is out of a predetermined load range, and the lift controlling part configured to control the control valve in accordance with the first open ratio when the blade load is within the predetermined load range.