Mine shield support frame - has pinion on rotatable guide rod, engaging on shield and floor plate end serrations

摘要

Interfacing ends of the break shield (2) and the floor plate (2) have end pieces, in arc form, with peripheral serration (8,9) on a shield support frame used in underground mining. The radius (15) of the serration on the floor plate end piece (7) is double that (14) of the serration on the break shield end piece (6). A guide-rod (5) bearing a pinion (12) combining with the serrations is rotatably attached in the centre of the circles of the connecting shield and plate. Its length between its hinges (10,11) equals the break shield length between one hinge and the cap hinge (2a). The cap hinge and the other hinge lie one above the other, in the initial position.