Drilling tool

A drilling tool configured to cooperate with a tooling including a guide orifice extending between a first wall of the tooling and a second wall of the tooling, the second wall being closer to a part to be drilled than the first wall, the drilling tool comprising:

• a hollow nose part having an outer guide surface, the hollow nose part being configured to allow a drill bit to pass therethrough in a drilling direction from the first wall to the second wall of the tooling;
• and
• a clamp including an elastic front part slidingly mounted on the outer guide surface of the hollow nose part via an inner guide surface, the elastic front part having a first end and an opposing second end, said elastic front part being rigidly connected to a rear movement part, a mechanism being connected to the rear movement part in order to move the clamp rearward along the hollow nose part in such a way that the elastic front part is expanded radially outward in an elastic manner,
• wherein the first end of the elastic front part comprises an outside bead protruding radially outward, configured to prevent translation of the drilling tool with respect to the tooling by bearing against the second wall of the tooling surrounding said guide orifice,
• wherein the clamp is configured to move, relative to the hollow nose part, from a retracted position to a deployed position,
• wherein the clamp is configured to be inserted through the guide orifice in the retracted position,
• wherein, in the deployed position, the elastic front part, including the outside bead protruding radially outward, is expanded radially, and the outside bead is configured such that, in the deployed position, the outside bead is expanded radially such that an outer extent of the bead is larger than said guide orifice, thereby allowing the outside bead to bear against the second wall of the tooling surrounding the guide orifice, preventing the sliding of the clamp and of the drilling tool with respect to the guide orifice in a direction opposite to the drilling direction,
• wherein during movement of the clamp rearward, in the direction opposite to the drilling direction, along the hollow nose part on a first section of length of the outer guide surface of the hollow nose part, the outer guide surface of the hollow nose part is configured so as to cause the clamp to transition from the retracted position of the clamp to the deployed position of the clamp,
• wherein the outer guide surface of the hollow nose part further comprises a second section of length, adjacent to the first section of length, configured to maintain the clamp in the deployed position, without increasing the diameter of the elastic front part by radial expansion, in such a way as to allow forward, in the drilling direction, movement of the hollow nose part towards a surface of the part to be drilled,
• wherein the hollow nose part includes an end surface, which is configured to bear against the surface of the part to be drilled in order to exert a desired stress, the outer guide surface of the hollow nose part including:
• a first guide surface extending from the end surface of the hollow nose part to an intermediate surface,
• a second guide surface, rearward, in the direction opposite to the drilling direction, of said first guide surface, the second guide surface defining the second section of length, and
• the intermediate surface having a flared shape connecting the first guide surface to the second guide surface, the intermediate surface defining said first section of length,
• wherein the elastic front part of the clamp comprises an inner bead protruding radially inward comprising said inner guide surface bearing against the outer guide surface of the hollow nose part,
• wherein the outer guide surface of the hollow nose part is configured so that:
• the retracted position of the clamp corresponds to the position of the clamp with respect to the hollow nose part in which the inner guide surface is in contact with the first guide surface of the outer guide surface of the hollow nose part, and
• a passage from the retracted position to the deployed position of the clamp corresponds to a position of the clamp with respect to the hollow nose part in which the inner guide surface slides on the first section of length of the intermediate surface, said inner guide surface cooperating with the second guide surface in such a way as to guarantee the maintaining in the deployed position of the clamp, without increasing the diameter of the elastic front part by radial expansion, to allow forward movement of the hollow nose part towards the surface of the part to be drilled to compensate for a relative movement between the guide orifice of the tooling and the surface of the part to be drilled during the drilling, and to compensate for deformation of the surface of the part to be drilled, and thus allow control of the stress exerted by the hollow nose part on the surface of the part to be drilled.