Longwall mining roof supports

A main gate roof support comprising:

• a first base portion for engaging a ground, the first base portion including a first support leg;
• a second base portion for engaging the ground and coupled to the first base portion, the second base portion including at least one second support leg;
• a third base portion for engaging the ground proximate a mine face and coupled to the second base portion, the third base portion including a third support leg;
• a first shield pivotally coupled to the first base portion;
• a first beam for engaging a mine roof, the first beam pivotally coupled to the first shield and coupled to the first support leg;
• a second beam for engaging the mine roof, the second beam pivotally attached to the first beam and coupled to the at least one second support leg;
• and
• a third beam for engaging the mine roof proximate a mine face, the third beam pivotally coupled to the second beam and coupled to the third support leg,
• wherein the first base portion, the second base portion, and the third base portion are defined by a first pontoon and a second pontoon spaced apart from the first pontoon,
• wherein the first beam, the second beam, and the third beam each span across the first pontoon and the second pontoon,
• further comprising a first bridge pivotally coupled between the first pontoon and the second pontoon, the first bridge including a leg, each of the pontoons including a pocket configured to receive the leg, the leg being rotatably supported in one of the pockets;
• and
• further comprising a second bridge pivotally coupled between the first pontoon and the second pontoon.

A main gate roof support comprising:

• two spaced apart pontoons, each pontoon including a hydraulically operable rearward support leg, a hydraulically operable forward support leg, and at least one hydraulically operable middle support leg;
• a rearward shield pivotally coupled to the pontoons by at least one rearward linkage;
• a rearward bridge pivotally coupled to each of the pontoons;
• a rearward roof-engaging beam pivotally coupled to the shield;
• the rearward roof-engaging beam coupled to the pontoons by the rearward support legs;
• a middle roof-engaging beam pivotally coupled to the rearward roof-engaging beam, the middle roof-engaging beam coupled to the pontoons by the at least one middle support legs;
• a middle bridge pivotally coupled to each of the pontoons;
• a forward roof-engaging beam pivotally coupled to the rearward roof-engaging beam, the forward roof-engaging beam coupled to the pontoons by the forward support legs;
• a forward bridge pivotally coupled to each of the pontoons;
• and
• a sloughing plate coupled to at least one of the pontoons.

A longwall mining system comprising:

• a main gate roof support including
• a pair of elongated base members laterally spaced apart from one another, each base member including a first portion, a second portion, a first support pivotally coupled to the first portion, and a second support pivotally coupled to the second portion,
• a first shield pivotally coupled to the first portion of each base member,
• a first beam coupled to the first portions of the base members by the first supports, the first beam pivotally coupled to the shield,
• a second beam coupled to the second portions of the base members by the second supports, and
• a bridge member pivotally coupled between each of the base members;
• a face end roof support positioned adjacent the main gate roof support, the face end support including
• a rear base,
• a rear shield pivotally connected to the rear base by a rear linkage,
• a rear beam for engaging the roof, the rear beam pivotally attached to the shield,
• a pair of spaced-apart rear support legs connected between the rear base and the rear beam,
• a forward base,
• a forward shield pivotally connected to the forward base by a forward linkage,
• a forward beam for engaging the roof, the forward beam pivotally connected to the rear beam, and
• a pair of spaced apart forward support legs connected between the forward base and the forward beam;
• a forward conveyor including a forward conveyor drive pivotally connected the forward base of the face end roof support;
• and
• a rear conveyor including a rear conveyor drive pivotally connected to the rear base of the face end roof support.