Patent ID: 8672414
Filing Date: 2014-03-18
Classification: E21C,E21D

Abstract:
1. A method for controlling a longwall mining operation in underground coal mining, including the steps of: providing a face conveyor; providing a disc shearer loader as an extraction machine; providing a hydraulic shield support frame that includes, as main components, a floor skid arrangement, a gob shield, a top canopy, and support connection rods; disposing inclination sensors on at least three of the group consisting of said floor skid arrangement, said gob shield, said support connection rods, and a gob-side region of said top canopy; ascertaining from said inclination sensors an inclination of those components of said shield support frame provided with said inclination sensors relative to a horizontal in a direction of movement; in a computer, comparing ascertained inclination data with base data stored in the computer that defines the geometrical orientation of said last-mentioned components and their movement during stepping; from said comparison, calculating a respective height of said shield support frame, perpendicular to a bed of said shield support frame, at a forward end of said top canopy, as a measure for a face opening; setting the height of the face opening calculated by the computer in relation to an overall disc cutting height of the disc shearer loader as said disc shearer loader travels past said shield support frame; wherein overall cutting height is given by the cutting heights of a leading one of the discs, which carries out an upper partial cut, and of one of the discs that carries out a lower partial cut, and wherein the cutting heights of the discs are ascertained on the basis of sensors that detect the position of the disc support arms.