| 摘要 |
A large hole earth boring bit with a clevis-type coupling for mounting the rolling cutters to the bit. The mounting apparatus includes a first member having two ends with aligned holes and a second member having its end inserted between the two ends. The end of the second member has an aperture that is spaced slightly out of alignment with the apertures in the first member, providing a generally elliptical passage. Bearing surfaces prevent them from coming into alignment. A pair of wedges are inserted into the elliptical passage and drawn together to exert a force in the direction toward alignment of the apertures. The force exerted is transmitted into the base, positively locking the two members together. |
