Patent · US Expired

Draft load measurement and control

US4807136A · kind A · utility

22Cited by
11References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1987
Grant dateFeb 21, 1989
Priority date
Expiry dateOct 26, 2007

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA01B63/112
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A tractor coupled to a draft implement through at least one link arm of a hydraulic lift assembly having a lift rod coupled between each link arm and a hydraulic cylinder for raising and lowering the draft implement. A force sensor is coupled to a link arm for providing a measurement of the total force exerted on the link arm. Electrical circuitry provides a measurement of the actual draft force by correcting the total force measurement for lift forces transmitted to the link arm through the corresponding lift rod. A feedback or draft control system is also provided for adjusting the depth of the draft implement in inverse relation to the corrected measurement of actual draft force.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.