| 摘要 |
<p>A forage harvester (11), pulled via its tongue (16) by a tractor, has dividers (19, 21) between which a crop row (18) is received, and each divider (19, 21) has a row sensing unit (41, 43) bolted to it. The crop row (18) passes between a pair of arms (47, 48) of the unit. An arm (47, 48) is deflected when the machine is misaligned within the row (18), the arm (47, 48) having an upright pivot shaft (79) which turns with it. The shaft (79) carried an actuator plate (95) which closes a switch (145) to trigger a guidance control circuit (45) to steer the harvester (11) by way of a piston and cylinder (33) moving the tongue (16) to return the harvester (11) to alignment with the crop row (18). The switch (145) is operated by a cam follower (183) which contacts a cam surface on the distal end of the actuator plate (95).</p> |
