Push rod resetting mechanism of needleless injector

Abstract

The invention relates to the technical field of needleless injectors, in particular to a push rod resetting mechanism of a needleless injector. The push rod resetting mechanism comprises an oil storage barrel for storing hydraulic oil, a pull rod and a resetting piston fixed at the front end of the pull rod, wherein the oil storage barrel is fixed on a gun body, the resetting piston is slidably mounted in the oil storage barrel, and a valve body is fixed at the front end of the gun body; and an oil return flow channel is formed in the valve body, the outer end of the oil return flow channel communicates with the front end of the oil storage barrel, the inner end of the oil return flow channel communicates with a part between a stepping piston and a hydraulic piston, and an oil return one-way valve used for preventing hydraulic oil between the stepping piston and the hydraulic piston from entering the oil storage barrel is arranged in the oil return flow channel. The oil return one-wayvalve is unlocked through an one-way unlocking structure, the oil return flow channel is opened, and therefore, when the pull rod is pulled backwards, the hydraulic oil between the stepping piston andthe hydraulic piston can be pumped into the oil storage barrel through the oil return flow channel, resetting of the stepping piston and the push rod fixed to the stepping piston is achieved, operation is easy, and resetting precision is high.

Description

technical field [0001] The invention relates to the technical field of needle-free injectors, in particular to a push rod reset mechanism for needle-free injectors. Background technique [0002] The working principle of the needle-free injector is to use the power source to release the power to generate instantaneous high pressure to push the liquid medicine to be sprayed out from the micron-sized pores. The high-speed liquid medicine flow will instantly penetrate the skin and reach the subcutaneous area, so that the liquid medicine is dispersed and distributed under the skin. , faster onset time and higher drug absorption rate; [0003] Needle-free injectors generally use a power mechanism to push the push rod to move at high speed in a straight line, so that the push rod quickly pushes the liquid medicine to form an injection, and the push rod is reset after injection. The rod directly pushes the push rod to reset, resulting in complicated operation and low reset accuracy...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is: in order to solve the problem that the needle-free syringe in the prior art usually adopts the method of directly pushing the push rod to reset, resulting in complicated operation and low reset accuracy, a needle-free injector is now provided. Push rod reset mechanism for needle syringe

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