# US 10,309,221 B2 · End coupling for a rock bolt > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,221 B2 - Document ID: US10309221B2 - Status: Granted - Kind: B2 - Application number: 15/522,313 - Filed: 2015-10-28 - Published: 2017-11-02 - Granted: 2019-06-04 - Earliest claimed: 2014-10-28 - Assignees: FCI Holdings Delaware, Inc. - Applicants: FCI Holdings Delaware, Inc. - Inventors: Peter Harold Craig; Matthew Raffaele Holden - Web page: https://patentgrep.com/patent/US10309221B2 ## CPC - E21D 21/008: {Anchoring or tensioning means} - E21D 21/0033: {having a jacket or outer tube} - E21D 21/0093: {Accessories} - E21D 20/02: with provisions for grouting - F16B 5/0275: {the screw-threaded element having at least two axially separated threaded portions (F16B5/0283 takes precedence)} - F16B 13/141: {Fixing plugs in holes by the use of settable material} - E21D: SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS (soil-conditioning or soil-stabilising materials C09K17/00; drilling or cutting machines for mining or quarrying E21C; safety devices, transport, rescue, ventilation or drainage E21F) - F16B: DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING (couplings for transmitting rotation F16D) ## Abstract An end coupling for a rock bolt having a shaft having an external thread, the coupling having an axis and the coupling comprising a body having a leading end and a trailing end spaced apart along the axis, a first passage portion extending along the axis from the leading end; a second passage portion extending along the axis from the trailing end; the first passage portion including a first thread portion to threadingly engage the external thread on the shaft of the rock bolt; the second passage portion including a drive receiving portion arranged to be engaged with a drive inserted into the second passage portion via the trailing end to impart rotation to the coupling about the axis. ## Claims ### Claim 1 An end coupling for a rock bolt having a shaft having an external thread, the coupling having an axis and the coupling comprising: a body having a leading end and a trailing end spaced apart along the axis, a first passage portion extending along the axis from the leading end; a second passage portion extending along the axis from the trailing end; the first passage portion defined in the body and including a first thread portion to threadingly engage the external thread on the shaft of the rock bolt; the second passage portion defined in the body and including a drive receiving portion arranged to be engaged with a drive inserted into the second passage portion via the trailing end to impart rotation to the coupling about the axis, wherein the second passage portion includes a second thread portion arranged to receive an attachment with a complementary thread received in the trailing end to threadingly engage the attachment to the end coupling, and wherein the drive receiving portion is defined inside of the body between the first thread portion and the second thread portion. ### Claim 2 (depends on 1) The end coupling according to claim 1, wherein the second thread portion is disposed intermediate the drive receiving portion and the trailing end. ### Claim 3 (depends on 1) The end coupling according to claim 1, wherein the drive receiving portion is disposed radially inwardly of the second thread portion. ### Claim 4 (depends on 1) The end coupling according to claim 1, wherein the second thread portion extends to the trailing end. ### Claim 5 (depends on 1) The end coupling according to claim 1, wherein the driving receiving portion is disposed at or adjacent the trailing end. ### Claim 6 (depends on 1) The end coupling according to claim 1, wherein the first and second passage portions are interconnected to form a continuous passage between the leading and trailing ends of the body. ### Claim 7 (depends on 1) The end coupling according to claim 1, wherein the drive receiving portion is in the form of an internal hex. ### Claim 8 (depends on 1) The end coupling according to claim 1, further comprising an abutment arrangement disposed on the body and forming an external abutment surface that faces the leading end. ### Claim 9 (depends on 8) The end coupling according to claim 8, wherein the abutment arrangement is disposed at or proximate the trailing end and forms an enlarged head on the body. ### Claim 10 (depends on 8) The end coupling according to claim 8, further comprising a washer that is receivable on the body and arranged to locate against the abutment arrangement. ### Claim 11 (depends on 8) The end coupling according to claim 8, wherein the abutment arrangement includes a bevelled surface that faces the leading end. ### Claim 12 (depends on 8) The end coupling according to claim 8, wherein the abutment arrangement is integrally formed with the body. ### Claim 13 (depends on 1) The end coupling according to claim 1, further comprising a torque transfer arrangement that is arranged to allow a threshold torque to be applied to the shaft through the coupling without inducing relative rotation between the coupling and the shaft. ### Claim 14 (depends on 13) The end coupling according to claim 13, wherein the torque transfer arrangement is in the form of shear pin. ### Claim 15 (depends on 1) A rock bolt assembly comprising: a rock bolt having a shaft having an external thread; and an end coupling according to claim 1, an end of the rock bolt disposed in the first passage portion and threadingly engaged with end coupling. ### Claim 16 (depends on 15) The rock bolt assembly according to claim 15, further comprising a torque transfer arrangement arranged to allow a threshold torque to be applied to the shaft through the coupling without inducing relative rotation between the coupling and the shaft. ### Claim 17 (depends on 16) The rock bolt assembly according to claim 16, wherein the torque transfer arrangement is in the form of shear pin extending between the coupling and the rock bolt shaft. ### Claim 18 (depends on 16) The rock bolt assembly according to claim 16, wherein the torque transfer arrangement is in the form of a sheer pin that extends across the first passage portion. ### Claim 19 (depends on 16) The rock bolt assembly according to claim 16, wherein the rock bolt is threadingly engaged with the end coupling such that when in a first position, rotation of the end coupling in one direction relative to the shaft allows for tensioning of rock bolt when installed by relative axial movement between the end coupling and the rock bolt shaft.