| 摘要 |
A turnable self-propelled, walk-along tractor vehicle, such as a plow for burying tubing is provided. The tractor vehicle has a pair of drive wheels rotatably mounted on a fixed axle in the front of the vehicle, a back support means, a U-shaped turning bracket mounted to the sides of the tractor vehicle, and optionally a vibrating blade for cutting a trench in the earth coupled at the rear of the vehicle. The back support means is mounted to the tractor vehicle at a first position elevated with respect to the ground and is adapted to engage the ground at a second position when downward force is applied to the turning bracket. The turning bracket comprises first and second portions, which may be flat or tubular in shape, which extend rearwardly from the sides of the tractor vehicle and substantially horizontally with respect to the ground when the back support means is in the first position. A third portion, which also may be flat or tubular in shape, extends perpendicular to and has juncture lines with the first and second portions. The lengths of the first and second portions are such that, by applying downward force to the third portion, the center of gravity of the tractor vehicle is shifted to lift the drive wheels from engagement with the earth and enable the vehicle to pivot on the back support means against the ground to effect a turn. In another embodiment, the tractor is equipped with pivot wheels to assist in turning the plow.
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