Latching and latch releasing mechanism for auger string couplings

Abstract

A lever-operated latching device for securing in endwise coupled relation a socket and mating shank of axially aligned auger sections of an auger mining machine, and a mechanism for automatically releasing essentially simultaneously a plurality of lever-operated latching devices of auger sections located in generally coplanar parallel adjacent alignment, the operating levels of the levers of which latching devices are subject to displacement from an intended coplanar relationship. The latching device is designed to be of minimum radial dimension so as to fit in a limited radial cross section of hole bored by the auger machine, and includes a latch pin that reciprocates in a passage formed in the socket between an extended position in latching engagement with the shank and a retracted unlatching position. The pin is biased by a spring toward its extended position and is retractable by a lever that engages a retractor element on the pin and which also has limit means that retains the pin in its extended position against the force of the spring. The mechanism for releasing essentially simultaneously a plurality of such lever-operated latching devices of adjacent auger sections comprises an unlatching member reciprocable toward and away from the levers between a retracted position and an extended position whereat contacting portions of the unlatching member can engage and pivot each of the levers to unlatch the devices even though the levers of one or more latching devices or auger sections are displaced from their desired coplanar relationship relative to the levers of other latching devices.