Abstract: A tandem drive assembly, sometimes called a drive or head section, for a belt conveyor having a pair of drive pulleys arranged in tandem, in which the main drive frame comprises separate, ground-engaging, foot members located respectively inbye and outbye of the drive pulleys, and a pair of longitudinal side members interconnecting the foot members. In the example illustrated, the side members are I-beams angularly inclined upwardly from the outbye foot member to the inbye foot member. The drive pulleys are rotatably journaled in bearings mounted on upper, angularly inclined surfaces of the side members to support the inbye drive pulley at a higher level than the outbye drive pulley. The lower surfaces of the side frames are likewise angularly inclined and provide ground level clearance through the sides of the main frame for access by a scoop or shovel to the area beneath the drive rollers where dust and fines are deposited by the conveyor belt.

Abstract: A mobile self-propelled mine roof support system employing pairs of individually self-propelled roof support units movable along opposite ribs of a mine room to follow an advancing mine face. Each support unit comprises an elongated, wheel-mounted frame positioned along the adjacent rib. Pairs of vertical jacks are connected to opposite sides of the frame, being positioned loosely, and vertically movable, within oversize openings in brackets attached to the frame. A foot plate is universally pivotally attached to the lower ends of each pair of jacks and extends across the underside of the frame. A top-supporting canopy is universally pivotally attached across the upper ends of each pair of jacks and has an overhanging portion extending cantileverly into the room toward the opposite support unit. The jacks have external flanges engagable with the brackets.