DRAG-LINE EXCAVATOR UNLOADING POSITION CONTROL DEVICE Russian patent published in 2007 - IPC E02F3/46 

FIELD: construction and mining, particularly dredgers and soil-shifting machines.

SUBSTANCE: method is based on bucket tilting angle regulation by differential control of two hoisting cables secured to bucket front and rear sides correspondingly. Method involves determining radius of cylindrical envelope surface having axis coinciding with that of drag-line body rotation on load-bearing base; calculating moment when rear cable connection point reaches said envelope surface; generating unloading control signal in this rear cable position. Cylindrical envelope surface radius is determined to approximate geometrical positions of points of rear hoisting cable connection to bucket at given bucket transfer angle, which enables to determine given unloading angle as front hoisting cable moves downwards.

EFFECT: simplified control, increased response and reliability of bucket unloading limit control, improved performance due to decreased production cycle time and increased operational safety.

8 cl, 5 dwg