Patent · US Expired

Electric circuit for controlling a tractor-pulled mounted device adjustable in height by a hydraulic jack

US4571500A · kind A · utility

12Cited by
4References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 24, 1984
Grant dateFeb 18, 1986
Priority date
Expiry dateApr 24, 2004

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA01B63/1117
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The position control and force control of a device mounted to a tractor, in particular for controlling the depth penetration of a plough, is supplemented by a lowering speed-responsive control to limit the lowering speed to a predetermined maximum value in order to increase safety of operation. Activating and disabling the lowering speed signal takes place in response to operating a mode select switch provided for the position control and force control as well as in response to a high-speed actuation of the mounted device. Furthermore, the lifting and lowering function of the hydraulic jack of the mounted device may be locked to prevent undesired motions of the mounted device when the system is put in operation.

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