# US 8,784,381 B2 · Drug injection device with acceleration sensor for detecting abnormal operation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,784,381 B2 - Document ID: US8784381B2 - Status: Granted - Kind: B2 - Application number: 13/148,364 - Filed: 2010-03-01 - Published: 2011-12-15 - Granted: 2014-07-22 - Earliest claimed: 2009-03-04 - Assignees: Panasonic Healthcare Co., Ltd. - Applicants: Atsushi Watanabe; Seiji Kikuchi; Tsuguhiro Kondo - Inventors: Atsushi Watanabe; Seiji Kikuchi; Tsuguhiro Kondo - Web page: https://patentgrep.com/patent/US8784381B2 ## CPC - A61M 5/5086: {for indicating if defective, used, tampered with or unsterile} - A61M 5/20: Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically (A61M5/142 takes precedence) - A61M 5/206: {with automatic needle insertion} - A61M 5/3146: {Priming, e.g. purging, reducing backlash or clearance} - A61M 5/31546: {Electrically operated dose setting, e.g. input via touch screen or plus/minus buttons} - A61M 5/326: {Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user} - A61M 2005/31588: {electrically driven} - A61M 2205/14: Detection of the presence or absence of a tube, a connector or a container in an apparatus - A61M 2205/215: Tilt detection, e.g. for warning or shut-off - A61M 2205/276: preventing unwanted use - A61M 2205/332: Force measuring means - A61M 2205/50: with microprocessors or computers - 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 A drug injection device includes a main body case having an injection needle let-in/let-out opening, a drug syringe mounting component that is provided inside the main body case and in which a drug syringe is mounted, a piston that is movable with respect to the drug syringe mounting component, a drive mechanism that drives the piston, a controller that is electrically connected to the drive mechanism, and an acceleration sensor that is electrically connected to the controller. This drug injection device allows the injection of a drug to be carried out safely and properly. ## Claims ### Claim 1 A drug injection device, comprising: a main body case having an injection needle let-in/let-out opening; a syringe unit inside the main body case and configured to be equipped with a drug syringe therein, the syringe unit comprising a piston and a first drive motor which drives the piston; a second drive motor configured to drive the syringe unit; a controller electrically connected to the first drive motor and the second drive motor; and an acceleration sensor electrically connected to the controller and being configured to detect acceleration applied to the main body case, wherein the controller stops the syringe unit from moving toward the injection needle let-in/let-out opening, or retracts the syringe unit away from the injection needle let-in/let-out opening, when the acceleration sensor has detected an acceleration of at least a first set value. ### Claim 2 (depends on 1) The drug injection device according to claim 1, wherein the controller stops the syringe unit from moving toward the injection needle let-in/let-out opening for a specific length of time, and then retracts the syringe unit away from the injection needle let-in/let-out opening, when the acceleration sensor has detected an acceleration of at least a first set value. ### Claim 3 (depends on 1) The drug injection device according to claim 1, wherein the acceleration sensor is configured to detect vibration of the drug injection device. ### Claim 4 (depends on 3) The drug injection device according to claim 3, wherein the controller is configured to determine whether the vibration detected by the acceleration sensor exceeds a first set value. ### Claim 5 (depends on 1) The drug injection device according to claim 1, wherein the acceleration sensor is disposed at a position that is spaced from a center of gravity of the main body case. ### Claim 6 (depends on 1) The drug injection device according to claim 1, wherein the controller stops the piston from moving toward the injection needle let-in/let-out opening when the acceleration sensor has detected an acceleration of at least a first set value. ### Claim 7 (depends on 6) The drug injection device according to claim 6, wherein the controller stores abnormality information in a memory when the acceleration sensor has detected an acceleration of at least a second set value that is greater than the first set value. ### Claim 8 (depends on 7) The drug injection device according to claim 7, wherein the abnormality information is information indicating that the main body case has been dropped. ### Claim 9 (depends on 1) The drug injection device according to claim 1, wherein the acceleration sensor is configured to further detect information about inclination of the main body case, and the controller is configured to acquire the information about the inclination of the main body case detected by the acceleration sensor, and based on the acquired information, determines whether or not air bleeding is possible and controls the first drive motor. ### Claim 10 (depends on 1) The drug injection device according to claim 1, wherein the controller stores abnormality information in a memory when the acceleration sensor has detected an acceleration of at least a second set value that is greater than the first set value.