Patent ID: 8616297

Claim:
A bulldozer comprising: a body; a drive unit configured to move the bulldozer; a ripper that is attached to a rear part of the body and performs ripping work; a ripper lifting device configured to raise and lower the ripper; a ripper tilting device configured to tilt the ripper in and out; an operating lever for operating the ripper, the operating lever being movably provided and configured to actuate the ripper lifting device and the ripper tilting device in accordance with a position of the operating lever; a steering lever that is movably provided and configured to control a travel operation by the drive unit in accordance with a movement direction of the steering lever; and a controller that is connected to send and receive signals from the operating lever, the steering lever, the ripper lifting device, and the ripper tilting device, the controller being configured to determine whether the ripping work has been ended based on the position of the operating lever and the movement direction of the steering lever, and automatically execute at least a first control of pulling the ripper up out of the ground by outputting a ripper lift command when the controller determines that the ripping work has been ended.