# US 12,766,261 B2 · Autoinjector for automatic injection of a medical product into an injection site > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,766,261 B2 - Document ID: US12766261B2 - Status: Granted - Kind: B2 - Application number: 18/215,865 - Filed: 2023-06-29 - Published: 2024-01-04 - Granted: 2026-10-20 - Earliest claimed: 2022-07-01 - Assignees: Becton Dickinson France - Applicants: Becton Dickinson France - Inventors: Arnaud Murier; Vincent Delobelle; Michael Fiard - Web page: https://patentgrep.com/patent/US12766261B2 ## CPC - A61M 5/20: Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically (A61M5/142 takes precedence) - A61M 5/31501: {Means for blocking or restricting the movement of the rod or piston (A61M5/5013 takes precedence)} - 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 autoinjector includes a housing extending along longitudinal axis (A) and configured to receive a medical container having a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with an injection needle and an opened proximal end. A power pack arranged inside the housing for expelling the medical product from the medical container. The power pack includes a plunger rod configured to extend through the opened proximal end of the barrel for pushing a stopper arranged inside the barrel. The plunger rod is axially movable between an initial position and an injection end position distally located with respect to the initial position. Resilient adjustment means are arranged between the plunger rod and the barrel for compensating clearances between the plunger rod and the barrel. ## Claims ### Claim 1 An autoinjector for automatic injection of a medical product into an injection site, the autoinjector comprising: a housing extending along a longitudinal axis (A) and configured to receive a medical container having a barrel defining a reservoir for containing a medical product, said barrel having a distal end provided with an injection needle and an opened proximal end, a power pack arranged inside the housing for expelling the medical product from the medical container, the power pack including a plunger rod configured to extend through the opened proximal end of the barrel for pushing a stopper arranged inside the barrel, the plunger rod being axially movable between an initial position and an injection end position distally located with respect to the initial position, and resilient adjustment means arranged between the plunger rod and the barrel for compensating clearances between the plunger rod and the barrel; wherein the resilient adjustment means are arranged on a plug attached to a distal end of the plunger rod; and wherein the plunger rod comprises a distal opening for receiving a connection portion of the plug and at least one axial slot configured to receive the resilient adjustment means. ### Claim 2 (depends on 1) The autoinjector according to claim 1, wherein the resilient adjustment means comprise a spring blade configured to deform in a radial inward direction so that the spring blade exerts a radial pushing force against the inner lateral wall of the barrel. ### Claim 3 (depends on 1) The autoinjector according to claim 1, wherein the spring blade has a fixed end secured to the plunger rod and a friction element configured to frictionally engage the inner lateral surface of the barrel. ### Claim 4 (depends on 3) The autoinjector according to claim 3, wherein the friction element is proximally located with regard to the fixed end. ### Claim 5 (depends on 3) The autoinjector according to claim 3, wherein the friction element is arranged at a free end of the spring blade. ### Claim 6 (depends on 3) The autoinjector according to claim 3, wherein the spring blade comprises an inclined outer side arranged between the fixed end and the friction element for easing insertion of the plunger inside the opened proximal end of the barrel. ### Claim 7 (depends on 6) The autoinjector according to claim 6, wherein the outer side has a convex and curved shape. ### Claim 8 (depends on 1) The autoinjector according to claim 1, wherein the resilient adjustment means are located at the distal end of the plunger rod. ### Claim 9 (depends on 1) The autoinjector according to claim 1, wherein the resilient adjustment means comprise a distal pushing area configured to push against the stopper. ### Claim 10 (depends on 1) The autoinjector according to claim 1, wherein the resilient adjustment means and the plug form a single piece. ### Claim 11 (depends on 10) The autoinjector according to claim 10, wherein the resilient adjustment means are overmolded on the plug. ### Claim 12 (depends on 1) The autoinjector according to claim 1, wherein the plug comprises a distal abutment surface configured to distally push against the stopper when the plunger rod moves to the injection end position. ### Claim 13 (depends on 1) The autoinjector according to claim 1, wherein the plug comprises a proximal shoulder configured to abut against a distal abutment surface of the plunger rod to stop insertion of the plug inside the plunger rod.