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(11) | EP 0 274 265 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Roller reamer assembly |
| (57) The invention relates to a drill member and particularly to a so called roller reamer.
Roller reamers are known to form part of a drill string whereby to maintain the gauge
of a hole during drilling, and known to comprise a number of roller cutters each mounted
on the spindle and located in equal spaced relationship around a carrier body. Ordinarily
the spindle is mounted in bearing blocks themselves located on a carrier body, and
it is known to pack grease around the spindle to minimise wear between the roller
cutter and the spindle during use. In use it is known for damage to be occasioned
to the bearing box and equally during long usage there can be a loss of lubricant/grease
from between the roller cutter and the spindle. The object of the invention is to
provide an improved cutter assembly for a roller reamer which objective is met by
a construction comprising a cutter assembly for a roller reamer comprising a tubular
spindle bearing blocks secured to the ends of the spindle and a rotary cutter rotatably
mounted on the spindle characterised by rotary seals 11 between the cutter 9 and the
spindle 4 at each end of the cutter, a spring loaded piston 12 mounted within the
tubular spindle 4, a passageway 16 through one bearing member 5 communicating with
the interior of the tubular spindle 4, valve or nipple means 17 closing the inlet
to the passageway 16 and at least one outlet hole 18 through the wall of the spindle
4 communicating with at least one groove 19 extending along the outer face of the
spindle 4 over substantially the length of the spindle 4 lying within the rotary
cutter 9. |