DRILLING BIT BEARING STRUCTURE

FIELD: mining. ^ SUBSTANCE: invention relates to rock destruction tools, in particular, to drilling bit bearing structures. This device includes a lug with journal provided with channels for lubricant feeding, a sealing element, and a roller bit. Roller bit is secured on said journal by means of friction bearing and retaining bearing. Friction bearing is provided with longitudinal grooves on its inner and outer surfaces, that are of segmented and triangular cross-section shape, and cut-through inclined channels, that connect grooves' cavities one to another. Area of grooves between said friction bearing and journal is not less than the area of grooves between roller bit and friction bearing. Axial channel of this journal is equipped with spring loaded check valve located in front of radial channels in said journal. ^ EFFECT: reduced impact loads of retaining drilling bit bearing and its extended service life, and, as a consequence, extended service life of entire bearing structure. ^ 3 cl, 2 dwg