GB856569A - Improvements in or relating to articulated shoring for use underground - Google Patents

Abstract

856,569. Hinges and pivots. PAURAT, F. W. March 10, 1958 [April 11, 1957], No. 7541/58. Class 65(2). A joint for articulated mine shoring comprises a section 1b, Fig. 2 having a part-cylindrical pivot socket 2b which receives a pivot pin 2c which pivots in another socket 2g on a further section 1g, the joint being secured by two safety rings 3a which loosely fit over projections 4b on the strut 1b and are held by pins 5 on the strut 1a. Alternatively the pin 2c may be welded to the top Ic, Fig. 3 of a pit prop 1a to pivot in a socket of a head plate 6, the rings 3a being bent to engage projections 6b welded to the plate 6. The pivot pin 2c may have a central collar which engages in recesses in tne sockets (Fig. 4, not shown) or the rings may have bayonet connections which pass through a cylinder containing the pin (Fig. 5, not shown). Alternatively the rings 3a may embrace half rings which have internal ribs engaging grooves in the pin 2c (Figs. 6 and 7, not shown).