Patent ID: 7762987

Claim:
A safety syringe device with a separable needle stem by turning back, comprising: a syringe tube containing a drug storing cavity with an inner thread section formed at a front end thereof, a tapered restriction space with a reduced diameter formed at the front end of the drug storing cavity, a needle hole bored through the restriction space to communicate with the drug storing cavity, and several stop protuberances provided around the inner circumferential surface of the restriction space; a push rod inserted into the syringe tube, having a top pusher with reduced diameter on the top thereof, and several clogs disposed around the lower outer circumference of the top pusher, a ring packed tightly against the wall of the drug storing cavity in the syringe tube, and a neck portion with reduced diameter formed under the ring; and a needle seat installed on the restriction space in the syringe tube, having a core bit with reduced diameter set on the front of the needle seat and extended out of a needle hole of the needle tube, the core bit being connected with a needle stem and covered with a needle stem and covered with a needle cap, wherein a passage is formed through the center of the core bit and an accommodation space is formed at the rear of the passage, several fixing blocks are provided on the surface of the accommodation space, a barrier space is formed between the adjacent fixing blocks to trap the clogs formed around the top pusher, around the outer circumference of the accommodation space in the needle seat there is provided with an outer thread section and a holding billet in correspondence with the inner thread section in the syringe tube to combine tightly with each other while the holding billet is engaged with the stop protuberance of the syringe tube.