| 摘要 |
A drill bit for drilling a borehole in an object, the drill bit having a central longitudinal axis and comprising a bit body provided with a central shank (2) for connecting the drill bit to a drilling system. The drill bit further comprises at least one cutting arm (9) , each cutting arm being provided with a set of cutters for cutting the object and being coupled to t he bit body via pivot means (10) allowing the cutting arm to pivot between a radially retracted position and a radially expanded position. The drill bit is provided with support means (12) for supporting the cutting arm in the radially expanded position thereof, wherein the support means is arranged to transmit at least a portion of the rotational torque generated during drilling, from the cutting arm to the bit body so as to reduce or prevent transmission of said rotational torque via the pivot means.
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