| 摘要 |
<p>An agricultural machine has at least one movable tool, such as a cultivating rotor, mower or raking member, spreader disc, or other driven member such as a tractor wheel or freely rotatable roller, which parts are interrupted in movement by a protective mechanism. The mechanism can be a pawl device associated with an overload coupling in the drive train that is actuated by a mechanical or electrical monitor to overload the device. The monitor can be a pivoted cover that partly overlies a rear roller or space adjacent same with projections that intercept the roller or a trip bar with contacts that opens or closes a circuit in a system that interrupts the drive to the moving parts responsive to contact with an external object. In another variation, the circuit can have sensors such as infrared or photoelectric cells to detect the presence or lack of presence of a human operator and these sensors can be placed in a tractor cab. Alternatively, the driver seat can be in the circuit to activate the circuit when the seat is vacated.</p> |
