| 摘要 |
PURPOSE:To apply large resistance to the side of a grounding device in turning course and prevent breakage of a grounding device, by providing grounding device-moving means for raising the device grounding to agricultural ground in giving steering angles having same phase to front and rear wheels. CONSTITUTION:When a change-over switch SW1 is operated to same phase side, a solenoid SOL1 rocking a rotary 2 to raising side is driven and after passing a prescribed time rotation of a motor M1 is reversed. The prescribed time is a time sufficient for the rotary to completely release contact state with an agricultural ground and intermediate gears 13b and 13c are made effective by reverse rotation of the motor M1 and steering angles given to front wheels 5a and 5b and rear wheels 6a and 6b become mutually same phase. |
