US 11,865,300 B2
Liquid medicine injection device
Jesse Jaejin Kim, Seongnam-si (KR); and Seung Ha Kim, Goyang-si (KR)
Assigned to EOFlow Co., Ltd., Seongnam-si (KR)
Filed by EOFLOW CO., LTD., Seongnam-si (KR)
Filed on Feb. 25, 2022, as Appl. No. 17/652,627.
Application 17/652,627 is a continuation of application No. 16/342,950, granted, now 11,291,764, previously published as PCT/KR2017/011378, filed on Oct. 16, 2017.
Claims priority of application No. 10-2016-0135264 (KR), filed on Oct. 18, 2016.
Prior Publication US 2022/0288301 A1, Sep. 15, 2022
Int. Cl. A61M 5/145 (2006.01); A61M 5/24 (2006.01); A61M 5/00 (2006.01); A61M 5/315 (2006.01)
CPC A61M 5/1452 (2013.01) [A61M 5/002 (2013.01); A61M 5/2422 (2013.01); A61M 5/31568 (2013.01); A61M 5/31501 (2013.01); A61M 2205/82 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A liquid medicine injection device comprising:
a liquid medicine storage unit including:
a cylinder including a space configured to store liquid medicine therein,
a discharge hole connected to the space, and
a piston arranged inside the cylinder and configured to move toward the discharge hole depending on discharge of the liquid medicine when present;
a first electrode on an outer surface of the cylinder;
a second electrode on the outer surface of the cylinder, the second electrode facing the first electrode with the piston therebetween;
a circuit unit electrically connected to the first electrode and the second electrode;
a case configured to receive the liquid medicine storage unit and the circuit unit;
a first conductive member located at an inner surface of the case and being along an outer surface of the liquid medicine storage unit, the first conductive member being electrically connected to the first electrode; and
a second conductive member electrically connected to the second electrode,
wherein the first electrode serves as a ground, and the second electrode is configured to receive a pulse signal applied by the circuit unit,
wherein the circuit unit is configured to calculate displacement information of the piston based on a capacitance change between the first electrode and the second electrode due to a difference between pulse response signals, and to thereby calculate an actual injected amount of the liquid medicine based on the displacement information of the piston,
wherein the first electrode is electrically connected to the circuit unit by the first conductive member,
wherein the second electrode is electrically connected to the circuit unit by the second conductive member, and
wherein at least one of the first conductive member or the second conductive member stably contacts at least one of the first electrode or the second electrode by an elastic force of an elastic member disposed inside the case.