Mine shaft wall retaining shield erection apparatus

摘要

The apparatus to erect retaining shields at mine shaft walls has a ball and socket for each connecting linkage (11). It has a linkage (10) fixed to each of the links (12), and a coupling link (15) at the part-shield (8) and/or the base frame (2). The linkage and the coupling form a moving support when coupled together, to give the swing movement for safe erection of the retaining shield structure.