| 摘要 |
An outer hollow tube has a rack which can engage a pinion in a crank housing which is clamped to the tongue of a trailer for raising and lowering the hollow tube. An inner hollow shaft is mounted for rotation within the outer tube and carries a steering handle at its upper end. A bracket is mounted to the lower end of the inner hollow shaft and a wheel is mounted for rotation about a horizontal axis to the bracket. An inner shaft extends through the hollow shaft and is connected to a gear train at its lower end for transmitting rotatiion of the inner shaft to rotation of the wheel in the bracket. A crank handle is connected to the upper end of the inner shaft. By manipulating the steering bar and crank handle, the wheel can be steered and driven to move the trailer tongue into a desired position with a socket of the tongue over a ball of a trailer hitch. In this position, the pinion is manually rotated by a second crank handle for raising the tube with respect to the tongue and thereby lowering the tongue.
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