| 摘要 |
986,472. Controlling tractors. C. VAN DER LELY N.V. Jan. 9, 1962 [Jan. 31, 1961], No. 816/62. Heading B7H. In a tractor having a driver's seat 7 mounted thereon so as to be rotatable about a vertical axis to any one of a number of different angular settings two control pedals 69, 70 rotatable with the seat are mounted on arms 71, 72 pivoted on a housing 25 supporting the seat and provided with adjustable studs 92, 92A (Fig. 8) each cooperating with one of two semi-circular coupling elements 86, 87 which encircle the rotational axis of the seat and are each mounted on a bellcrank 95 which is pivoted on the frame 1 of the tractor and is connected by a draw-rod 101 to the braking mechanism of one of driving wheels 2, 3. The ends 89, 91 of the coupling elements 86, 87 overlap so that each stud 92, 92A engages the same coupling element when the seat 7 is rotated through 90 degrees to either side of the straight ahead position but each stud engages the opposite coupling member when the seat is rotated through more than 90 degrees. A spring- loaded pin 80 (Fig. 4) interconnecting the control pedals 69, 70 may be retracted and retained by a pin 81 so that steering may be assisted by differential braking of the wheels 2, 3. Coil springs 110 resiliently support the seat 7 on four parallel arms 16 connected to support plates 23 secured to the housing 25. A cylindrical portion 26 (Fig. 5) of the housing 25 is detachably mounted over a support 29 bolted to the frame 1 and is formed internally with two rims 34, 35 which register with spaced rings 30, 31 on the support 29. A locking pin 115 on the housing 25 engages one of recesses 116 in the ring 30 to retain the seat 7 in a chosen angular setting. A steerable front wheel 4 of the tractor is controlled by levers 36, 37 journalled in universal ball and socket joints at either end of boxshaped portion 27 extending transversely of the housing 25. The levers 36, 37 are connected at their lower ends to U-shaped brackets 46 at either end of a coupling member 47 disposed within the box-shaped portion 27 and connected at its centre by means of a ball and socket joint with a vertical crank pin 58 (Fig. 5) on an arm 59 secured to a vertical shaft 10 journalled in spaced bearing 61 and carrying at its lower end an arm 64 connected by a coupling rod 66 (Fig. 4) with the wheel 4. A control lever 8 pivoted on the frame 1 is connected by arms 10, 12 and a coupling rod 10 to a shaft 13 controlling an hydraulic transmission coupling an internal combustion engine 5 with the wheels 2, 3 and arranged to drive the tractor in either direction at the same speed and with the same tractive effort. The tractor is provided with a three-point lifting device 6. The invention may be applied to a tractor having caterpillar tracks and steered solely by differential braking. |
