Abstract: A longwall mining system includes at least one face end roof support having a longitudinal length, and at least one near end roof support adjacent the face end roof support. The near end roof support has a longitudinal length substantially shorter than the face end roof support longitudinal length. There is also at least one face roof support adjacent the near end roof support, and the face roof support has a longitudinal length substantially shorter than the near end roof support longitudinal length. There is also a forward conveyor extending forward to and attached to the face end roof support, the at least one near end roof support, and the at least one face roof support, and a rearward conveyor extending rearward of and attached to the face end roof support, the at least one near end roof support, and the at least one face roof support.

Abstract: A cooling system for the gear case in the ranging arm of a longwall shearer, the ranging arm including a plurality of single gears mounted in a row within an elongated housing. The cooling system includes a coolant injection system in each of the single gears, each coolant injection system including a longitudinal opening in the gear axle, and a coolant injection tube mounted inside the longitudinal opening. The coolant injection tube has a diameter smaller than the diameter of the longitudinal opening. A coolant supply line is connected to and in communication with the coolant injection tube, and a coolant outlet is connected to and in communication with the longitudinal opening adjacent the one end of the longitudinal opening, so that coolant leaving the end of the coolant injection tube travels back along the coolant injection tube and then out of the gear axle thereby removing heat from the single gear.

Abstract: An electric vehicle powered by a trailing cable, the vehicle including a cable guide for guiding cable onto a reel as the cable is paid out and taken up. The cable guide comprises a pair of adjacent, double flanged concave rollers in alignment with each other so that their respective flanges are spaced apart by only a small distance substantially less than the cable diameter so that an essentially closed circular path is defined by the concave surfaces of the adjacent rollers so that the cable can not escape the rollers, each of the rollers including a polyurethane core that is hard and slick that creates a natural bearing surface, and an outer portion made of softer polyurethane than the core that aids in gripping and guiding the cable onto the cable reel.

Abstract: A cylinder assembly for supporting a device above a surface, the device including a base, the cylinder assembly including a cylinder, mounted on the base, and extendable perpendicular to the base. The cylinder assembly further includes a foot at the end of the cylinder away from the base, and a locking mechanism for locking the cylinder in its fully extended position, the locking mechanism comprising a track attached to the base, and a track rod connected to and movable along the track, between a cylinder retraced position and a cylinder extended position. The locking mechanism also includes a brace pivotally attached at one end to the track rod, and pivotally attached at another end to the foot, and a fixing mechanism for fixing the track rod in the cylinder extended position.

Abstract: A continuous mining machine cutting head structure is set forth. The head member is of the type having axially extensible and retractable end portions. Included within the head member is a toroidal hydraulic cylinder for selectively extending and retracting these end portions.

Abstract: A mining machine includes a light source and a roof support guide for detecting the relative angular alignment between the mining machine and the roof support. The light source in the form of a laser on the mining machine, directed toward the roof support. The roof support guide is on the roof support above the mining machine, so that when the alignment between the mining machine and the roof support is as desired, light from the light source falls in a predetermined location relative to the roof support guide. When the mining machine is not in proper alignment with the roof support, the light source does not fall within the predetermined location relative to the roof support guide.

Abstract: A mining machine comprising a discharge boom including a tail slide plate slidably connected between left and rear side frames, and a tail roller assembly mounted on the tail slide plate. The tail roller assembly includes a take-up roller mounted centrally between the side frames and between a pair of spacer blocks and a pair of bearing blocks, each of the spacer blocks and bearing blocks being connected to a rearward edge of the tail slide plate. The mining machine also has an opening in each of the side frames, and two slide plate guides, one on each side frame, each of which is positioned outside of the respective side frame adjacent a respective one of the side frame openings, and mounted for sliding movement relative to its respective side frame.

Abstract: A conveyor flight for a chain comprising at least two spaced apart links, and two side plates that connect the links, with each side plate including two spaced apart extension pins extending from the side plate. The flight comprises a metal support, and the metal support includes two spaced apart cylindrical portions adapted to receive the two spaced apart extension pins. The flight also includes a flexible casing surrounding the metal support.