Draft sensing apparatus wherein effect of vertical deflection reduced to insignificant levels compared to horizontal deflection
US4266616A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1979 |
| Grant date | May 12, 1981 |
| Priority date | — |
| Expiry date | Jun 29, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L5/136
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.