SHIELD MOVE-APART CEILING Russian patent published in 1999 - IPC

FIELD: mining industry, development of thick steeply steep seams by shield system. SUBSTANCE: shield move-apart ceiling has two rows of beams, upper and extendible lower, installed in parallel one to another and hydraulic jacks for telescopic movement of lower row relative to upper one. It is assembled from sections of single type, mounted in series one close to another with sides and covered by elastic cover. Each section has automatic adjustment of length. Sections are intercoupled in the form of string by two parallel rows of flexible ties positioned along diagonally opposite edges of upper row of beams. Length of flexible tie does not exceed height of section. Lower edge of extendible row of beams is bevelled. EFFECT: reduced mass of structure and automatic adjustment in correspondence with changing thickness. 6 dwg