# US 11,905,987 B2 · Security device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,905,987 B2 - Document ID: US11905987B2 - Status: Granted - Kind: B2 - Application number: 17/334,967 - Filed: 2021-05-31 - Published: 2021-12-16 - Granted: 2024-02-20 - Earliest claimed: 2018-02-26 - Assignees: Hexlox Ug - Applicants: Ian Patrick Berrell; Susanne Dorusz - Inventors: Ian Patrick Berrell; Susanne Dorusz - Web page: https://patentgrep.com/patent/US11905987B2 ## CPC - F16B 41/005: {Measures against unauthorised operation of bolts, nuts or pins (F16B23/0007, F16B23/0061, F16B23/0069, F16B23/0076 and F16B31/02 take precedence; locks, keys E05B; for valves, taps or cocks F16K35/00; for pipe-joints with swivel-nuts F16L19/005)} - F16B 41/00: Measures against loss of bolts, nuts, or pins; Measures against unauthorised operation of bolts, nuts or pins ({locking of screws, bolts or nuts F16B39/00;} seals G09F3/00) - 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 A security plug (10) adapted to be inserted into the female socket (18) of a fastener (20) to prevent a tool, such as an Allen key, engaging in the female socket. The plug (10) has an outer surface (22) complementary to the female socket (18) and a retaining member (14) that retains the plug (10) in the female socket (18), and at least one removal portion (26, 70) adapted to be engaged by a second tool (100), whereby engagement of the second tool (100) and the plug (10) allows forces applied by the second tool (100) to the plug (10) to withdraw the plug from the female socket against the action of the retaining member. The second tool and the removal portion (26, 70) may have complementary self-holding tapers and the retaining member (14) may be a magnet or one or more biased members that engage side walls(s) of the female socket. ## Claims ### Claim 1 A security plug for a fastener having a longitudinally extending female socket adapted to receive a first tool, the plug adapted to be inserted into the female socket to prevent the first tool engaging in the female socket, the plug comprising: an outer surface portion complementary to the female socket; at least one retaining member for retaining the plug in the female socket, and at least one removal portion comprising at least one first engagement surface adapted to be engaged by a second tool having at least one second engagement surface complementary to the at least one first engagement surface, whereby mechanical engagement of the at least one first and second engagement surfaces provides engagement between the second tool and the plug to allow force applied longitudinally by the second tool on the plug to withdraw the plug from the female socket against the action of the at least one retaining member, wherein at least one first engagement surface has a self-holding taper has an included taper angle between 1 and 10 degrees. ### Claim 2 (depends on 1) A security plug of claim 1 wherein a self-holding taper comprises a Morse taper, a Brown Et Sharpe taper, a Jacobs taper or a Jarno taper. ### Claim 3 (depends on 1) A security plug of claim 1 wherein one of the first and second engagement surfaces comprises a female engagement surface and the other of the first and second engagement surfaces comprises a male engagement surface adapted to be received within the female engagement surface and wherein, when the first and second engagement surfaces are engaged together, the male engagement surface expands the female engagement surface very slightly and the resulting compressive forces applied by the female engagement surface to the male engagement surface over the overlapping regions of male and female surfaces hold the security plug and the second tool together. ### Claim 4 (depends on 1) A security plug of claim 1 wherein the plug has first and second longitudinal ends and the at least one removal portion is located at or adjacent the first longitudinal end and the at least one retaining member is located at or adjacent the second longitudinal end, the plug adapted to be inserted into the female socket with the at least one retaining member engaging an inner end of the female socket or at least one side wall of the female socket. ### Claim 5 (depends on 4) A security plug of claim 4 wherein the retainer comprises at least one leg biased to engage the at least one side wall. ### Claim 6 (depends on 5) A security plug of claim 5 wherein the at least one leg extends outwardly toward the first longitudinal end. ### Claim 7 (depends on 5) A security plug of claim 5 comprising at least one leg receiving recess for receiving the at least one leg. ### Claim 8 (depends on 5) A security plug of claim 5 wherein the at least one leg extends at an angle to the longitudinal direction of between 10 and 40 degrees. ### Claim 9 (depends on 5) A security plug of claim 5 wherein the at least one leg extends at an angle to the longitudinal direction of between 20 and 30 degrees. ### Claim 10 (depends on 5) A security plug of claim 5 wherein the at least one leg extends at an angle to the longitudinal direction of about 21 degrees. ### Claim 11 (depends on 1) A security plug of claim 1 wherein the plug is integrally formed with the retainer member. ### Claim 12 (depends on 1) A security plug of claim 1 comprising a shell and a separate retainer member connected to the shell. ### Claim 13 (depends on 12) A security plug of claim 12 wherein the retainer member is connected to the shell by at least one of adhesive, glue, bonding agent, weld, rivet, bolt, screw, interference fit pin, clip, circlip and biased arm(s). ### Claim 14 (depends on 12) A security plug of claim 12 comprising at least one securing member that engages the shell to secure the retaining member to the shell. ### Claim 15 (depends on 14) A security plug of claim 14 wherein the at least one securing member engages a peripheral surface of the shell. ### Claim 16 (depends on 14) A security plug of claim 14 wherein the retainer member comprises the at least one securing member. ### Claim 17 (depends on 14) A security plug of claim 14 wherein the retainer member and the at least one securing member are separate components. ### Claim 18 (depends on 17) A security plug of claim 17 wherein the at least one securing member passes through the retainer member to engage the shell and secure the retainer member to the shell. ### Claim 19 (depends on 18) A security plug of claim 18 wherein the shell comprises at least one further recess or bore and the at least one securing member is received in the at least one further recess or bore. ### Claim 20 (depends on 19) A security plug of claim 19 wherein the at least one further recess or bore and the at least one securing member have complementary threads and the at least one securing member screws into the shell. ### Claim 21 (depends on 19) A security plug of claim 19 wherein the at least one further recess or bore and the at least one securing member are an interference fit. ### Claim 22 (depends on 19) A security plug of claim 19 comprising at least one longitudinally extending first recess comprising said at least one first engagement surface and the at least one further recess or bore extends to the first recess. ### Claim 23 (depends on 19) A security plug of claim 19 wherein the at least one bore is a blind bore. ### Claim 24 (depends on 17) A security plug of claim 17 comprising at least one head and the retaining member is sandwiched between the shell and the at least one head. ### Claim 25 (depends on 24) A security plug of claim 24 wherein the at least one head engages the at least one securing member. ### Claim 26 (depends on 24) A security plug of claim 24 wherein the at least one head comprises a clip, including a circlip. ### Claim 27 (depends on 14) A security plug of claim 14 wherein the at least one head is integral with the at least one securing member.