Patent ID: 8562561

Claim:
A safety syringe with retractable rotation, the safety syringe comprising: a barrel, having a receiving cavity formed in the barrel, at least one stopper arranged at an open end of the receiving cavity, and at least one guiding pressure plate arranged at a tail end of the barrel, wherein limit grooves of said guiding pressure plate are arranged corresponding to and toward an inner portion of the receiving cavity; a needle set, limited at the open end of the barrel and including a rotating member and a stopping member engaged with each other, wherein an auto deflection device is disposed between the rotating member and the stopping member, and the auto deflection device has a rotated portion arranged inside the rotating member and a non-circular groove arranged at a predetermined position inside the stopping member, and an embedding portion is arranged at an end of the rotating member relative to the rotated portion, wherein at least one L-shaped groove is arranged at an outer ring edge of the rotating member for limiting and aligning with the stopper of the barrel so that the rotating member, stopping member and the barrel are locked with each other in a locking mode, and an assembling member is arranged at a rear end of the rotating member for embedding with the rotating member; and a plunger, having at least one radial rib arranged at outer edge, wherein the radial rib is guided by the limit groove of the guiding pressure plate and formed a linear track, wherein a poking portion and a non-circular section are arranged at a front end of the plunger, and the non-circular section is assembled corresponding to the non-circular groove arranged inside the stopping member, so that the plunger is only allowed to move linearly, and when the plunger is pushed forward, an inclined groove arranged at the poking portion engages and exerts force to a guiding inclined plane of the rotating member to separate the L-shaped groove of the rotating member with the stopper of the barrel to release the locking mode between the rotating member, stopping member and the barrel.