Boring head
AssigneeSantrade Ltd.
InventorsBernt S. Liljekvist, Anders E. Persson
Life of this patent
Estimating the term…
Abstract
A boring head for reaming a pre-drilled hole in raise boring or for similar earth cutting operations comprising a plurality of roller cutters (13, 14), each of which being rotatably journalled over a bearing system. The bearing system comprises a split roller bearing (60) having axially spaced rollers (62, 63) which are separated by a loose guide ring (69).
Claims8
A rotary boring head for boring the face of earth formations, said boring head being of the type comprising a mounting means, a plurality of bearing shafts carried by said mounting means, and a plurality of roller cutters rotatably journaled on said shafts by a bearing system which comprises at least a first bearing set including a plurality of rollers spaced apart in the longitudinal direction of the respective roller cutter, the improvement, wherein:
- said bearing shaft has a first race of a first diameter, said roller cutter having a second race of a second diameter larger than said first diameter,
- said longitudinally spaced rollers of said first bearing set being seated between said first and second races such that said first and second races are common to said longitudinally spaced rollers, and
- a guide ring disposed between said longitudinally spaced rollers and being loosely mounted relative to said bearing shaft and said roller cutter.
A boring head for rotary boring of the face of earth formations comprising a plurality of roller cutters which are rotatably journaled on bearing shafts over a bearing system, said bearing shaft being carried by a mounting means on the boring head, said bearing system comprising a roller bearing having rollers which are spaced in the longitudinal direction of the roller cutter, characterized in that the rollers have common races on the bearing shaft and on the roller cutter, and in that a guide ring is arranged between the spaced rollers, said guide ring being loose with respect to the bearing shaft and the roller cutter, the bearing system comprises two roller bearings, said roller bearings being arranged at opposite ends of the roller cutter and having different diameters, characterized in that the guide ring of the larger roller bearing is arranged adjacent to the race thereof on the bearing shaft, and that the guide ring of the smaller roller bearing is arranged adjacent to the race thereof on the roller cutter.
A boring head for rotary boring of the face of earth formations comprising a plurality of roller cutters which are rotatably journaled on bearing shafts over a bearing system, said bearing shaft being carried by a mounting means on the boring head, said bearing system comprising a roller bearing including rollers which are spaced in the longitudinal direction of the roller cutter, characterized in that the rollers have common races on the bearing shaft and on the roller cutter, and in that a guide ring is arranged between the spaced rollers, said guide ring being loose with respect to the bearing shaft and the roller cutter, the height of the guide ring when measured at a race adjacent thereto is smaller than half the diameter of a roller.
Dependencies are inferred from the claim text.