| 摘要 |
<P>PROBLEM TO BE SOLVED: To simplify hydraulic circuits by supplying discharge oil in the hydraulic circuit for power steering to the hydraulic circuit for front wheel acceleration and/or the hydraulic circuit for brake. <P>SOLUTION: A steering controller for a tractor 10 is provided with the hydraulic circuit 60 for power steering and the hydraulic circuit 25 for front wheel acceleration. When a front wheel 12 is steered and a steering angle of the front wheel 12 exceeds, for example, 40 degrees, discharge oil from the hydraulic circuit 60 for power steering is supplied to the hydraulic circuit 25 for front wheel acceleration, a front wheel acceleration device 26 operates, rotary peripheral speed of the front wheel 12 is increased more than rotary peripheral speed of a rear wheel 14, and the front wheel 12 rotates at a higher speed than ordinary speed. Consequently, a machine body can turn in small rotation radius. At the same time, if brake force is applied to the rear wheel 14R (or 14L) on an inner side of turn, the machine body can turn in smaller rotation radius. <P>COPYRIGHT: (C)2003,JPO |
