Method of mining coal seams at a defined preset depth of cutting during ploughing with a cutter
First Claim
1. A method of mining coal seams at a defined preset depth of cutting during ploughing by a cutter, which method comprises positioning a longwall conveyor along a coal face, moving the longwall conveyor forwards through a defined preset cutting depth by extending self-advancing cylinders, pivoting the said cylinders at one end to the longwall conveyor and at the other end to roof supports disposed parallel to the longwall conveyor, controlling the advance of the longwall conveyor in dependence on a piston stroke of a respective self-advancing cylinder, making the advance in individual defined partial strokes using travel-measuring signals generated at each partial stroke, and, after a predetermined maximum total piston stroke has been reached, automatically retracting the roof support connected to the respective self-advancing cylinder, moving the said roof support forwards by the maximum total piston stroke, and then re-setting the roof support, increasing the distance covered by the partial strokes corresponding to the preset depth of cutting by an amount sufficient to compensate an average mechanical clearance at the pivot points of the self-advancing cylinders, fixing a defined face line inside the face in the form of a final value with respect to a centre of rotation on the side of a main or auxiliary drive of the cutter so that the final value forms a straight line through the centre of rotation, and pivoting the straight line through an angle <
- 90°
with respect to the respective preceding initial face line which lies on a straight line likewise passing through the centre of rotation so that a circular segment is mined.
2 Assignments
0 Petitions
Accused Products
Abstract
In a method of mining coal seams using a ploughing cutter, a longwall conveyor extending along the coal face is moved forwards by the extension of self-advancing cylinders, the advance being controlled in dependence on a piston stroke of a respective self-advancing cylinder and being made in individual defined partial strokes using travel-measuring signals generated at each partial stroke. The distance covered by the partial strokes corresponds to the preset depth of cutting and is increased by an amount sufficient to compensate an average mechanical clearance at the pivot points of the self-advancing cylinders. In addition, a defined face line is fixed with respect to a center of rotation on the side of a main or auxiliary drive of the cutter so as to form a straight line through the center of rotation, the straight line being pivoted through an angle <90° so that a circular segment is mined.
10 Citations
8 Claims
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1. A method of mining coal seams at a defined preset depth of cutting during ploughing by a cutter, which method comprises positioning a longwall conveyor along a coal face, moving the longwall conveyor forwards through a defined preset cutting depth by extending self-advancing cylinders, pivoting the said cylinders at one end to the longwall conveyor and at the other end to roof supports disposed parallel to the longwall conveyor, controlling the advance of the longwall conveyor in dependence on a piston stroke of a respective self-advancing cylinder, making the advance in individual defined partial strokes using travel-measuring signals generated at each partial stroke, and, after a predetermined maximum total piston stroke has been reached, automatically retracting the roof support connected to the respective self-advancing cylinder, moving the said roof support forwards by the maximum total piston stroke, and then re-setting the roof support, increasing the distance covered by the partial strokes corresponding to the preset depth of cutting by an amount sufficient to compensate an average mechanical clearance at the pivot points of the self-advancing cylinders, fixing a defined face line inside the face in the form of a final value with respect to a centre of rotation on the side of a main or auxiliary drive of the cutter so that the final value forms a straight line through the centre of rotation, and pivoting the straight line through an angle <
- 90°
with respect to the respective preceding initial face line which lies on a straight line likewise passing through the centre of rotation so that a circular segment is mined. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
- 90°
Specification