Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB136141A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
DAVID JOHN MORRISSEY
Original Assignee
DAVID JOHN MORRISSEY
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by DAVID JOHN MORRISSEYfiledCriticalDAVID JOHN MORRISSEY
Priority to GB136141ApriorityCriticalpatent/GB550650A/en
Publication of GB550650ApublicationCriticalpatent/GB550650A/en
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
E21D15/48—Chocks or the like
Abstract
550,650. Pit props. MORRISSEY, D. J. Oct. 24, 1941, No. 1361. Drawings to Specification. [Class 20 (ii)] A pit prop comprises a concrete main prop member with wedge-shaped end recesses disposed transversely of each other, to receive upper and lower wooden bearers, shaped to fit into the recesses.
GB136141A1941-10-241941-10-24Roof supports for coal mines
ExpiredGB550650A
(en)