Self-propelled mine roof supporting column - has roof bogie mounted on arm which pivots on universal joint

摘要

The supporting column is movable by its own propulsion mechanism, while remaining capable of supporting a load continuously. It comprises two parallel bogies forming feet and joined by two cross-members, and a roof bogie parallel to them and thrust upwards by a ram acting against the cross-members. The foot bogies pivot on the cross-members on lengthwise axes, and are joined to each other by a lengthwise member, at one end of which is a hinging arm supporting the roof bogie at the free end. The arm(581) hinges on a universal joint(575), one of whose pivot axes(576) is parallel to the cross-members, while the other(574) extends towards the arm.