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AssigneeHydro-Quebec
InventorsPeter Szita, Louis Dubreuil
Estimating the term…
A multiple trepan boring device for producing substantially large cuts in large works, such as concrete dams, comprises a drilling shaft adapted to be translationally displaced along its longitudinal axis and carrying a series of spaced apart cylindrical rotatable trepans each having a peripheral cutting surface and an annular cutting surface, the latter extending in plane perpendicular to the axis of the shaft and radially between the shaft and the peripheral cutting surface. Weights apply continuous downwards forces on the shaft and thus on the trepans. With the trepans resting on the top of the work to be cut, the trepans are rotated in place, and under the aforementioned forces the peripheral cutting surface of each trepan bores a hole until the shaft rests on the top of the work. Then the shaft is displaced translationally while the trepans continue to rotate thereby causing the annular cutting surfaces to remove a layer of the work extending between the shaft and the peripheral cutting surface. This procedure is repeated so as to produce a cut of a width corresponding to the outside diameter of the trepans by successive removal of crescent-shaped layers from the work. After the removal of each layer, the shaft is lowered along a distance corresponding to the difference in radii between the drilling shaft and the trepans.
A boring device for producing cuts in large works, comprising a drilling shaft, motor means for rotatably driving said drilling shaft, at least one trepan means mounted on said drilling shaft and adapted for rotation therewith, said drilling shaft and said trepan means being adapted to be translationally displaced along a rotational axis thereof, said drilling shaft and said trepan means being positioned in use on a large work to be cut and opposite a location of a cut to be produced by said device, said trepan means being of transverse dimensions greater than said drilling shaft and including cutting means extending outwardly of said drilling shaft and in at least one plane non parallel to said axis, whereby while said drilling shaft and said trepan means are being rotated by said motor means, at least said trepan means can be translationally displaced along said axis such that said cutting means removes a layer means from the large work of a width substantially corresponding to outside transverse dimensions of said cutting means and of a maximum thickness at most equal to a radial distance between said drilling shaft and an outside edge of said cutting means.
A method for producing cuts in large works, comprising the steps of:
Dependencies are inferred from the claim text.