# US 10,307,544 B2 · Differential gear mechanism for a drug delivery device and drug delivery device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,544 B2 - Document ID: US10307544B2 - Status: Granted - Kind: B2 - Application number: 15/310,208 - Filed: 2015-05-27 - Published: 2017-05-18 - Granted: 2019-06-04 - Earliest claimed: 2014-05-28 - Assignees: Sanofi-Aventis Deutschland GmbH - Applicants: Sanofi-Aventis Deutschland GmbH - Inventors: Matthew Meredith Jones; Samuel Keir Steel; Neal Alexander Blundred; Joseph Butler; Robert Frederick Veasey; David Plumptre; Anthony Paul Morris - Web page: https://patentgrep.com/patent/US10307544B2 ## CPC - A61M 5/31575: {using scaling up or down transmissions, e.g. gearbox} - A61M 5/19: having more than one chamber - A61M 5/2448: {comprising means for injection of two or more media, e.g. by mixing} - A61M 5/31515: {Connection of piston with piston rod} - A61M 5/31528: {by means of rotational movements, e.g. screw-thread mechanisms} - A61M 5/31538: {Permanent blocking, e.g. by medical personnel} - A61M 5/31551: {including axial movement of dose setting member} - A61M 5/31561: {using freely adjustable volume steps} - A61M 5/31585: {the component being manually operated or triggered by an axially moving actuator operated by user, e.g. an axially movable injection button} - A61M 5/31591: {Single dose, i.e. individually set dose administered only once from the same medicament reservoir, e.g. including single stroke limiting means} - A61M 5/31593: {Multi-dose, i.e. individually set dose repeatedly administered from the same medicament reservoir} - A61M 5/31596: {comprising means for injection of two or more media, e.g. by mixing} - A61M 5/3295: {Multiple needle devices, e.g. a plurality of needles arranged coaxially or in parallel} - A61M 2005/1787: {Syringes for sequential delivery of fluids, e.g. first medicament and then flushing liquid} - A61M 2005/244: {by flexible clip} - A61M 2005/3126: {related to dosing} - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract The disclosure is directed to a differential gear mechanism for a drug delivery device with a primary drug delivery assembly and a secondary drug delivery assembly, wherein the primary drug delivery assembly comprises a primary dose dial sleeve and wherein the secondary drug delivery assembly comprises a secondary drive sleeve. The disclosure is also directed to a respective drug delivery device. ## Claims ### Claim 1 A differential gear mechanism for a drug delivery device with a primary drug delivery assembly comprising a primary dose dial sleeve and with a secondary drug delivery assembly comprising a secondary drive sleeve, the differential gear mechanism comprising: a first toothing; a transmission element movable relative to the first toothing in a first axial direction and comprising at least one first gear wheel and at least one second gear wheel, the second gear wheel concentrically arranged with respect to the first gear wheel; a second toothing configured to be axially constrained to the primary dose dial sleeve; a third toothing configured to be axially constrained to the secondary drive sleeve; and a fourth toothing, wherein each of the first toothing, the second toothing, the third toothing, and the fourth toothing are formed as a gear rack, wherein the second toothing, the third toothing, and the fourth toothing are moveable relative to the first toothing in the first axial direction, wherein the first gear wheel is in meshed engagement with the first toothing and the fourth toothing, and wherein the second gear wheel is in meshed engagement with the second toothing and the third toothing. ### Claim 2 (depends on 1) The differential gear mechanism according to claim 1, wherein the fourth toothing is movable relative to the second toothing in the first axial direction. ### Claim 3 A drug delivery device comprising: a primary drug delivery assembly comprising a primary dose dial sleeve configured to move proximally in a helical movement during setting of a dose of a primary medicament contained in a primary reservoir of the primary drug delivery assembly; and a secondary drug delivery assembly comprising a secondary drive sleeve configured to move in a proximal direction in a helical movement during setting of a dose of a secondary medicament contained in a secondary reservoir of the secondary drug delivery assembly; and a differential gear mechanism comprising: a first toothing; a transmission element movable relative to the first toothing in a first axial direction and comprising at least one first gear wheel and at least one second gear wheel, the second gear wheel concentrically arranged with respect to the first gear wheel; a second toothing axially constrained to the primary dose dial sleeve; a third toothing axially constrained to the secondary drive sleeve; and a fourth toothing; wherein the second toothing, the third toothing and the fourth toothing are moveable relative to the first toothing in the first axial direction wherein the first gear wheel is in meshed engagement with the first toothing and the fourth toothing, and wherein the second gear wheel is in meshed engagement with the second toothing and the third toothing. ### Claim 4 (depends on 3) The drug delivery device of claim 3, wherein the fourth toothing is moveable relative to the second toothing in the first axial direction. ### Claim 5 (depends on 3) The drug delivery device of claim 3, wherein when the secondary drive sleeve moves proximally, axial motion of the third toothing causes relative axial movement between the second toothing and the fourth toothing. ### Claim 6 (depends on 3) The drug delivery device of claim 3, wherein when the primary dose dial sleeve moves proximally, motion of the second toothing in a proximal direction causes the second toothing and the fourth toothing to move together in the proximal direction. ### Claim 7 (depends on 3) The drug delivery device of claim 3, wherein the first toothing is fixed stationary with respect to a drug delivery housing. ### Claim 8 (depends on 7) The drug delivery device according to claim 7, wherein the primary dose dial sleeve is a number sleeve with indices for indicating the value of a set dose. ### Claim 9 (depends on 7) The drug delivery device according to claim 7 further comprising a movable element movable with respect to the primary dose dial sleeve between a first position and a second position, wherein the fourth toothing is arranged to move the movable element from the first position into the second position during dose setting of the secondary drug delivery assembly. ### Claim 10 (depends on 9) The drug delivery device according to claim 9, wherein the movable element is a dispense button. ### Claim 11 (depends on 9) The drug delivery device according to claim 9, wherein the movable element is configured to move the fourth toothing in a distal direction when the movable element is moved from the second position into the first position. ### Claim 12 (depends on 9) The drug delivery device according to claim 9, wherein the primary dose dial sleeve is configured to move proximally in a helical movement during dose setting and to move distally in a helical movement during dose dispense, wherein an actuation element is axially constrained to the second toothing. ### Claim 13 (depends on 12) The drug delivery device according to claim 12, wherein the actuation element is a dose dial element. ### Claim 14 (depends on 12) The drug delivery device according to claim 12, wherein the actuation element at least partly accommodates the movable element. ### Claim 15 (depends on 12) The drug delivery device according to claim 12, wherein the movable element is movable relative to the actuation element in an axial direction, wherein when the movable element is moved from the second position to the first position, the movable element engages the actuation element such that further movement of the movable element in a distal direction is transferred to the actuation element. ### Claim 16 (depends on 3) The drug delivery device according to claim 3, wherein the primary drug delivery assembly comprises a variable dose setting mechanism and wherein the secondary drug delivery assembly comprises a fixed dose setting mechanism. ### Claim 17 (depends on 3) The drug delivery device according to claim 3, wherein the primary drug delivery assembly accommodates a primary medicament and the secondary drug delivery assembly accommodates a secondary medicament. ### Claim 18 (depends on 17) The drug delivery device of claim 17, wherein at least one of the primary medicament and the secondary medicament comprises a pharmaceutically active compound.