Patent ID: 8784374

Claim:
A disposable self-destructive syringe, comprising: a cylinder, having a flat tubular inwall, bonding with an injecting needle; a sealing plug disposed in said cylinder to slide along said inwall thereof in a sealed manner; a one piece integrated injecting piston-rod having a front end coupling with said sealing plug to move said sealing plug within said cylinder, wherein said injecting piston-rod has a center gap defining a center ratchet groove at a front portion of said injecting piston-rod and a reciprocal motion region at a rear portion of said injecting piston-rod; and an anti-return member slidably coupling with said injecting piston-rod in unidirectional manner, wherein when said injecting piston-rod is pulled backward for sucking liquid into said cylinder, said anti-return member is retained along said reciprocal motion region of said center gap for enabling said injecting piston-rod being reciprocally moved for expelling inhaled air out of said cylinder, wherein when said injecting piston-rod is pushed backward to move said anti-return member from said reciprocal motion region of said center gap to said ratchet groove, said anti-return member fixes at said injecting piston-rod along said ratchet groove, wherein when said injecting piston-rod is pushed forward during injection process, said injecting piston-rod and said anti-return member are moved at the same time, wherein said anti-return member pierces into said inwall of said cylinder, such that after said injection process is completed, said anti-return member is affixed in said cylinder to prevent said injecting piston-rod being pulled back in said cylinder.