| 摘要 |
1,151,157. Automatic steering control. HUDSWELL YATES DEVELOPMENTS Ltd. March 6, 1968 [March 10, 1967], No. 11289/67. Heading G3R. [Also in Division A1] Mole plough apparatus consists of a mole plough blade 27 attached to a tracked vehicle 8 which moves forward by means of cables 20 attached to a ground anchor 21 and two laterally spacedwinches 18 mounted on the vehicle and means for controlling the relative effective length of the cables whereby to control the attitude of the vehicle and hence that of the blade 27 about an axis perpendicular to the ground. The winches 18 are driven by hydraulic motors 23, 24 controlled by pumps 28, 30 via links 40, 42 and levers 36, 38. Automatic steering is provided by the inclusion of ram assembly 44 between portions 42a, 42b of link 42. A deviation from the desired path is detected by the automatic steering gear (not shown) and results in pulse energization of line 76 or 78. This causes the solenoid operated valve 68 to feed hydraulic fluid through pipe 64 or 66 temporarily displacing the ram either to the right or to the left and thus shortening or lengthening link 40. This will produce the desired correction in the steering and the ram returns to its original position under the action of springs 58. To connect the automatic steering, levers 36, 38 are latched together thus operating electric switch (88) which holds valve 68 in the "off" position until the switch is operated, see Fig. 6 (not shown), for general speed change, levers 36, 38 can be operated together. The relative length of the cables can be altered in other ways for example by moving one of the winches in a longitudinal direction or moving a pulley or another member into contact with the cables. |
