| 摘要 |
<p>The invention relates to a power drive system for a set of landing legs for equipment such as a vehicle trailer or dock leveller, which legs are extendable and retractable by mechanical actuating means including a rotatable shaft, characterised by an air driven rotary motor (28) adapted to be mounted so that its driven shaft extends generally longitudinally of the vehicle by a speed reduction gear (43) drivingly connected to said driven shaft by means (44) to turn the drive line of said driven shaft through substantially ninety degrees so that it is directed transversely of the vehicle by means (39) to connect said speed reduction gear (44) drivingly to an end of the rotatable shaft (38) and by directional control valve means (18) for the motor whereby a supply of pressurised air may be selectively applied to the motor (28) to drive it in either direction to cause extension and retraction of the landing legs (33).</p> |
