# US 11,298,755 B2 · Device for securely attaching a drilling device to a drill plate including an expandable collet with balls > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,298,755 B2 - Document ID: US11298755B2 - Status: Granted - Kind: B2 - Application number: 16/709,282 - Filed: 2019-12-10 - Published: 2020-06-11 - Granted: 2022-04-12 - Earliest claimed: 2018-12-11 - Assignees: Etablissements Georges Renault - Applicants: Etablissements Georges Renault - Inventors: Remi Bos - Web page: https://patentgrep.com/patent/US11298755B2 ## CPC - B23B 49/023: {Bushings and their connection to the template} - B23B 41/00: Boring or drilling machines or devices specially adapted for particular work {(surgical drilling machines A61B17/16)}; Accessories specially adapted therefor - B23B 49/02: Boring templates or bushings - B23B 2215/04: Aircraft components - B23B: TURNING; BORING (arrangements for copying or controlling B23Q) ## Abstract A device for securely attaching a drilling device to a drill plate provided with a plurality of positioning bores. The attachment to the drill plate including an expandable collet with balls. ## Claims ### Claim 1 A device for securely attaching a drilling device to a drill plate traversed by a plurality of positioning bores, said device for securely attaching comprising: a body; a first attachment to securely attach said body to said drilling device; a second attachment to securely attach said body to said drill plate, said second attachment comprising an expandable collet, said expandable collet comprising: an expandable ring traversed by a conical bore made along a longitudinal axis of said expandable ring; an expansion cone housed within said conical bore of said expandable ring, an external peripheral outline of said expansion cone being complementary to said conical bore, a translational drive, which drives in translation said expansion cone within said conical bore along said longitudinal axis between at least: a releasing position in which said cone is shifted to a largest-diameter side of said conical bore of said expandable ring so much so that said expandable ring is in a relaxed state in which the expandable ring's external diameter is smaller than a diameter of said positioning bores so that said expandable ring can be inserted therein or extracted therefrom; a locking position in which said cone is shifted to a smallest-diameter side of said conical bore of said expandable ring so much so that said expandable ring is in an expanded state in which the expandable ring's external diameter is increased so as to keep said device for securely attaching securely attached to said drill plate by friction of said expandable ring against internal walls of one of said positioning bores; wherein said expandable collet furthermore comprises locking balls each housed in a hole made in said expandable ring, said expansion cone acting on said locking balls to place them in: an unblocking position, taken when said cone is situated in the cone's releasing position, in which said locking balls do not form protrusion on an external peripheral surface of said expandable ring; a blocking position, taken when said cone is situated in the cone's locking position, in which said locking balls form protrusions on the external peripheral surface of said expandable ring so that said locking balls can get housed in a peripheral blocking housing securely attached to said positioning bores. ### Claim 2 (depends on 1) The device according to claim 1 wherein said balls are housed in longitudinal grooves made on the surface of said expansion cone. ### Claim 3 (depends on 2) The device according to claim 2 wherein each of said grooves comprises a first stage and a second stage separated by an inclined ramp, a bottom of said first stage being closer to a longitudinal axis of said expansion cone than a bottom of said second stage, said balls being situated against said first stage in said unblocking position and against said second stage in said blocking position. ### Claim 4 (depends on 3) The device according to claim 3 wherein said grooves are not through grooves. ### Claim 5 (depends on 1) The device according to claim 1, wherein said positioning bores are made in said drill plate. ### Claim 6 (depends on 5) The device according to claim 5, wherein said peripheral blocking housings are made in said drill plate. ### Claim 7 (depends on 1) The device according to claim 1, comprising guidance rings configured to be securely attached to said drill plate and traversed by said positioning bores. ### Claim 8 (depends on 7) The device according to claim 7, wherein each of said guidance rings comprises a shoulder with a shape complementary to a housing made in said positioning bores of said plate. ### Claim 9 (depends on 8) The device according to claim 8 wherein said shoulder is made to a side of said plate that is opposite to a side oriented towards said device for securely attaching. ### Claim 10 (depends on 7) The device according to claim 7, wherein said peripheral blocking housings are made said guidance rings. ### Claim 11 (depends on 7) The device according to claim 7, wherein said body comprises a stop that is configured to abut against a surface of said guidance rings oriented towards said device for securely attaching. ### Claim 12 (depends on 1) The device according to claim 1, wherein said body comprises a stop that is configured to abut against a surface of said drill plate. ### Claim 13 (depends on 1) The device according to claim 1, wherein the passage of said cone from its releasing position to its locking position is done in the direction of a surface of said drill plate oriented towards said device for securely attaching, or vice versa. ### Claim 14 (depends on 1) The device according to claim 1, wherein said translational drive comprises a cylinder assembly, said cylinder assembly comprising a cylinder made within said body and a piston mounted so as to be mobile in translation within said cylinder along the axis of translation of said expansion cone, said expansion cone being securely attached in translation to said piston. ### Claim 15 (depends on 14) The device according to claim 14 wherein said cylinder assembly is a double-action cylinder assembly. ### Claim 16 (depends on 14) The device according to claim 14, wherein said cylinder of said cylinder assembly comprises a locking chamber placed on one side of the piston and configured to be powered to shift said expansion cone into its locking position and a releasing chamber placed on the other side of the piston and configured to be powered to shift said expansion cone into its releasing position, the surface area of a face of the piston situated in said releasing chamber being greater than a surface area of a face of said piston situated in said locking chamber. ### Claim 17 (depends on 1) The device according to claim 1 comprising a regulator, which regulates the translational drive, said regulator being configured so that the speed of shift in translation conveyed to said expansion cone by said translational drive is greater during its passage from said releasing position to said locking position than it is during its passage from said locking position to said releasing position. ### Claim 18 (depends on 1) The device according to claim 1, wherein the device is traversed from one side to the other through by a drill jig bushing.