| 摘要 |
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 passes between a pair of arms (47, 48) of the unit. An arm (47, 48) is deflected when the machine is misaligned with the row (18), the arm (47, 48) having an upright pivot shaft (79) which turns with it. The shaft (79) carries an actuator plate (95) which closes a switch (145) to trigger a guidance control circuit (45) to steer the harvester by way of a piston and cylinder (33) moving the tongue (16) to return the harvester to alignment with the crop row (18). A housing (149) is provided for covering the switch (145, 147) and the top of the pivot shaft (79). The switch (145, 147) is mounted on a floor (151) of the housing (149). The pivot shaft (79) extends through the floor (151) and is partly surrounded by a first wall (153) of the housing, the wall (153) opening toward the switch (145, 147). The housing (149) has a removable cover (157) which completes the enclosure of the switch (145, 147). |
