| 摘要 |
A draft sensing apparatus for an agricultural tractor or the like. The tractor is provided with a transversely extending bending shaft (18). The forward ends of a pair of lower draft links are secured to the outer ends of the shaft (18). The shaft (18) will bend in proportion to the draft in the links. The draft is sensed through a Hall effect device (52) carried by a yoke (54). The forward end of the yoke (54) is pivotally mounted on a fixed transversely extending shaft (48) and the rear portion of the yoke slideably receives the bending shaft (18). A link (60) pivoted to the yoke (54) has one end portion contacted by the shaft (18) and the other end is in contact with one end of a spring biased pin (70). The other end of the pin carries a permanent magnet (78) in axially alignment with the sensor (52). As the shaft deflects as the draft varies the magnet (78) will be shifted towards and away from the sensor (52) causing a voltage variation in line (98). By mounting the sensor (52) in the manner indicated the effect of vertical deflection of the bending shaft (18) will be reduced to insignificant levels as compared to horizontal deflection. |
