DRILLING CONE BIT Russian patent published in 2006 - IPC E21B10/22 

FIELD: rock cutting tools, particularly core bits characterized by bearing or lubricating details.

SUBSTANCE: cone bit comprises body, axles with race tracks and ball delivery channels, as well as rolling cutters supported by axles by means of bearings and provided with mating race tracks. Axle race tracks are made as inclined crossing annular channels. Rolling cutter race tracks are formed as single annular boring having width corresponding to maximal distance between axle race tracks. One axle race track has sections of different diameters. Section having lesser diameter is made in upper axle part and is located from trailing edge thereof. Above section is connected with ball delivery channel. Axle has additional channel, which connects ball delivery channel with lower part of race track nearer to axle base.

EFFECT: increased load-bearing capacity of drilling bit bearing assembly along with maintenance of retaining bearing workability.

3 cl, 1 dwg