A needle-free automatic injection syringe is a device that delivers drugs into the skin and tissues using a high-speed fluid jet without using an injection needle. This technology is attracting attention as an efficient means of vaccine delivery in the veterinary and livestock fields that reduce the risk of cross-infection and require mass vaccination. In particular, animal vaccination provides various advantages over conventional needle injection methods in terms of worker safety, inoculation speed, and maintenance cost. This paper was conducted to solve the problem of pressure loss at the nozzle discharge side of the existing Jet Injector in designing the flow path of the animal vaccine-free automatic injection syringe nozzle. To this end, the flow rate of the air tank (receiver) was determined, the needleless injection was basically designed, and the simulation was performed to prove its validity. Through these series of processes, the design review of the driving part was completed, and through this, the nozzle and neck-up shape were proposed to obtain the desired performance. However, it is thought that more trial and error are needed to commercialize such a needleless injection to humans.

Abstract
1. 서 론
2. 무침 자동 주사기의 설계검토
    2.1 에어탱크(리시버) 및 유량 결정
    2.2 무침 주사 기본 설계
    2.3 시뮬레이션 수행
3. 무침 자동 주입 주사기의 노즐 및목업 형상 제안
4. 결 론
References

• 이정익(Dept. of Mechanical design, INHA Technical College) | Jeong-Ick Lee Corresponding author
• 김병삼(Dept. of Mechanical engineering, Wonkwang University) | Byoung-Sam Kim