# US 7,407,440 B2 · Drive shaft coupling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,440 B2 - Document ID: US7407440B2 - Status: Granted - Kind: B2 - Application number: 11/457,471 - Filed: 2006-07-14 - Published: 2006-12-21 - Granted: 2008-08-05 - Earliest claimed: 1999-05-14 - Assignees: Precimed S.A. - Inventors: Patrick M. White - Web page: https://patentgrep.com/patent/US7407440B2 ## CPC - G06K 19/07703: {the interface being visual} - A61B 17/162: {Chucks or tool parts which are to be held in a chuck} - A61B 17/1631: {Special drive shafts, e.g. flexible shafts (A61B17/1642, A61B17/164 take precedence)} - B23B 31/117: Retention by friction only, e.g. using springs, resilient sleeves, tapers - B23B 45/005: {Flexible shafts} - B23B 51/04: {Drills} for trepanning - B23D 77/00: Reaming tools - F16D 1/087: {due to other loading elements in the hub or shaft} - F16J 15/064: {the packing combining the sealing function with other functions} - F16J 15/0806: {characterised by material or surface treatment} - F16J 15/0887: {the sealing effect being obtained by elastic deformation of the packing} - F16J 15/164: {the sealing action depending on movements; pressure difference, temperature or presence of leaking fluid} - G06K 17/00: Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations - G06K 19/04: characterised by the shape - G06K 19/06: characterised by the kind of the digital marking, e.g. shape, nature, code - G06K 19/07: with integrated circuit chips - G09F 21/02: by a carrier person or animal - A61B 2017/00862: {elastic or resilient} - A61B 2090/031: {torque limiting} - B23B 2228/16: Shape memory alloys - Y10S 464/902: Particular material - Y10T 403/557: Expansible section - G06K: GRAPHICAL DATA READING (image or video recognition or understanding G06V); PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - B23B: TURNING; BORING (arrangements for copying or controlling B23Q) - B23D: PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR (making toothed gears or the like B23F; cutting metal by applying heat locally B23K; arrangements for copying or controlling B23Q) - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS - G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A flexible torque-transmitting coupling assembly and method is disclosed, as well as flexible surgical reamers having such assemblies. The reamers employ a fitting with radially flexible member, e.g., a split collet or a super-elastic collar that receives an elongated tubular shaft of super-elastic alloy. A compression sleeve is applied to the collet, in one embodiment, while the collar is located within a counter-bore of the fitting in another embodiment. Relative motion between the shaft, fitting and collet (or collar) induces a super-elastic activation in the shaft to form the desired coupling. ## Claims ### Claim 1 A torque-transmitting assembly comprising: a) a female coupling member with a bore; b) a radially flexible member, received within the bore, defining a hollow shape with an opening, the radially flexible member being made of super-elastic alloy; and c) an elongated shaft member made of a super-elastic alloy, received within the opening, wherein forcing the radially flexible member onto the shaft causes the radially flexible member to contact the shaft, inducing a super-elastic activation in the shaft and further induces a super-elastic activation of the radially flexible member that urges the shaft and radially flexible member into surface-to-surface contact, securing the members together in a fixed relative position. ### Claim 2 (depends on 1) The assembly of claim 1, wherein the super-elastic alloy is a nickel-titanium alloy. ### Claim 3 A torque-transmitting coupling assembly comprising: a) a tool fitting member formed with a counter-bore; b) a collar member being a series of washers made of super-elastic alloy, having an exterior surface and an opening, the collar being located in the counter-bore; and c) an elongated shaft member made of a super-elastic alloy, received within the opening, whereupon relative motion between the fitting (120) and the collar (125) causes the collar (125) to contact the shaft (105), inducing a super-elastic activation in the shaft (105) that engages the shaft (105) and collar into surface-to-surface contact, securing the members (105, 120, 125) together in a fixed relative position. ### Claim 4 (depends on 3) The assembly of claim 3, wherein engagement of the exterior surface with the counter-bore compresses the opening against the shaft. ### Claim 5 (depends on 4) The assembly of claim 4, wherein the engagement occurs along one or more contact areas that frictionally carries the applied torque. ### Claim 6 (depends on 5) The assembly of claim 5, wherein the contact area is calibrated so that the coupling slips at a preset torque before the fatigue strength of the shaft is reached. ### Claim 7 (depends on 3) The assembly of claim 3, wherein the super-elastic alloy is a nickel-titanium alloy. ### Claim 8 (depends on 3) The assembly of claim 3, wherein the shaft is tubular with a cannulation. ### Claim 9 (depends on 8) The assembly of claim 8, wherein the fitting has a cannulation aligned with the shaft cannulation, for common passage of a guide wire there through. ### Claim 10 (depends on 3) The assembly of claim 3 further comprising an inter-positional polymer sleeve for transmitting bending stress in the assembly. ### Claim 11 (depends on 3) The assembly of claim 3, wherein the fitting further comprises a cutting tool-bit. ### Claim 12 An interference fit drive shaft coupling for a rotary surgical tool comprising: a tool fitting (20) adapted to receive a rotary surgical cutting tool, the fitting (20) having a fitting cannulation (22); a collet (25) in line and integral with the tool fitting (20), the collet having a compression sleeve (10) slid over it, and having a collet cannulation (22) concentric with the fitting cannulation (22) of the tool fitting (20), the collet cannulation (22) having a contact surface (30) with an inner diameter (D2); and a flexible drive shaft (5) made of a nickel-titanium alloy and having a shaft cannulation (7), the nickel-titanium alloy having metal alloy properties selected from the group consisting of: martensitic properties and super-elastic properties and adapted to transfer torque while subjected to bending forces during use, the drive shaft (5) securely receivable in the collet (25) by an interference fit between an outer diameter (D1) of shaft (5) and the inner diameter (D2) of the contact surface (30) of the collet (25), the interference fit induced by a super-elastic activation in the shaft (5) that engages the shaft (5) and collet into surface-to-surface contact, and disposing the shaft (7) cannulation to be substantially concentric with the fitting cannulation (22) to provide said interference fit drive shaft coupling. ### Claim 13 A torque-transmitting coupling assembly comprising: a) a tool fitting member formed with a counter-bore; b) a collar member being a washer made of super-elastic alloy, having an exterior surface and an opening, the collar being located in the counter-bore; and c) an elongated shaft member made of a super-elastic alloy, received within the opening, whereupon relative motion between the fitting (120) and the collar (125) causes the collar (125) to contact the shaft (105), inducing a super-elastic activation in the shaft (105) that engages the shaft (105) and collar into surface-to-surface contact, securing the members (105, 120, 125) together in a fixed relative position. ### Claim 14 (depends on 13) The assembly of claim 13, wherein engagement of the exterior surface with the counter-bore compresses the opening against the shaft. ### Claim 15 (depends on 14) The assembly of claim 14, wherein the engagement occurs along one or more contact areas that frictionally carries the applied torque. ### Claim 16 (depends on 15) The assembly of claim 15, wherein the contact area is calibrated so that the coupling slips at a preset torque before the fatigue strength of the shaft is reached. ### Claim 17 (depends on 13) The assembly of claim 13, wherein the super-elastic alloy is a nickel-titanium alloy. ### Claim 18 (depends on 13) The assembly of claim 13, wherein the shaft is tubular with a cannulation. ### Claim 19 (depends on 18) The assembly of claim 18, wherein the fitting has a cannulation aligned with the shaft cannulation, for common passage of a guide wire there through. ### Claim 20 (depends on 13) The assembly of claim 13, further comprising an inter-positional polymer sleeve for transmitting bending stress in the assembly. ### Claim 21 (depends on 13) The assembly of claim 13, wherein the fitting further comprises a cutting tool-bit.