Abstract: An intravenous catheter insertion device is disclosed to include a barrel, which has a body and a stop wall, a deformable portion extending from the body, a retainer connected with the deformable portion, and a press portion for pressing by the user to deform the deformable portion. A needle set, which has a cylindrical needle holder, a needle fastened to the needle holder at the front side, a springy stop portion extending from the needle holder, and a retainer connected with the needle holder near the front end of the needle holder. And a spring member, which is mounted around the needle set inside the barrel, and has a first end stopped against the stop wall of the barrel and a rear end stopped against the springy stop portion of the needle set.

Abstract: A blood sampler is disclosed to include a needle holder for holding a needle, and a barrel, which has a front neck for holding the needle holder and the attached needle in the operative position, a longitudinal sliding slot for guiding movement of the needle holder and the attached needle from the operative position to the received position inside the barrel after the application of the blood sampler, a turning slot for guiding the needle holder from the front neck into the longitudinal sliding slot, and a retainer provided at the bottom side of the longitudinal sliding slot to secure the needle holder to the received position.

Abstract: A hypodermic syringe includes a barrel, the barrel having two stop portions in the rear side, a radially compressible constraint member mounted in the barrel and stopped between the stop portions of the barrel, and a plunger holding a rubber stopper and axially movably inserted through the constraint member into the inside of the barrel, the plunger having a breaking portion, and front stop flange, which is stopped against the constraint member upon back stroke of the plunger after use of the syringe for enabling the user to break the breaking portion.

Abstract: A safety fluid injecting/sampling apparatus connectable with a needle cannula, the apparatus includes an inner barrel having a receiving hole, an elastically bendable retaining strip with an inwardly protruded engagement tooth disposed at one end, and a retaining hole disposed at the other end, an outer barrel having an axially extended receiving hole adapted to receive the inner barrel, a finger flange extended around the periphery, and an elastically deformable retaining element having an engagement block engageable into the retaining hole of the inner barrel; a needle holder axially slidably inserted into the receiving hole of the inner barrel, the needle holder having a locating groove extended around the periphery and adapted to receive the engagement tooth of the inner barrel for positioning, and an insertion member inserted into the receiving hole of the inner barrel for operation by hand to move the outer barrel backwards relative to the inner barrel.

Abstract: A hypodermic syringe includes a barrel, the barrel having two stop portions in the rear side, a radially compressible constraint member mounted in the barrel and stopped between the stop portions of the barrel, and a plunger holding a rubber stopper and axially movably inserted through the constraint member into the inside of the barrel, the plunger having a breaking portion, and a front stop flange, which is stopped against the constraint member upon back stroke of the plunger after the service of the syringe for enabling the user to break the breaking portion.

Abstract: A fluid injecting/sampling apparatus is constructed to include a barrel, a needle holder holding a needle cannula, a plunger mounted with a rubber stopper and axially movably mounted in the barrel, and a rotary chuck coupled to the front end of the barrel and prohibited from a reversed rotation after having been turned relative to the barrel to unlock the needle holder for enabling the needle holder to be pulled backwards into the inside of the barrel by the plunger.

Abstract: A safety syringe comprises a barrel, which has a body forming a receiving hole, a stop portion in the receiving hole. A needle holder has a hole therein, an elastic lock piece formed a claw at distal end, and a dragged portion. The needle holder is received in the receiving hole of the barrel for the claw can lock with the stop portion of the barrel. A supporter, which is slidable received in the hole of the needle holder for supporting the elastic lock pieces to make the needle holder fixed secured in the barrel. And a plunger set has a bumper to move away said supporter and withdraw said needle holder.

Abstract: A safety syringe comprises a barrel having a projection in a rear end thereof, a needle holder for mount of a needle, the needle holder having a dragged portion, a stopper movable in the barrel, the stopper having a drag portion adapted for engaging into the dragged portion of the needle holder and a plunger connector, a plunger for moving the stopper in the barrel having a stopper connector engaged with the plunger connector of the stopper. When pulled backwards to the end after injection, the plunger connector of the stopper is forced onto the projection of the barrel and disengaged from the plunger, enabling the plunger to be removed from said barrel.

Abstract: A safety syringe comprises a barrel having a grip lug with two fitting holes and two retaining holes communicating with each other; an elastic lashing member capable of retracting elastically and inwards, and having two locating pillars which are provided with an arresting head being retained in the retaining holes of the barrel, two slide confining portions being disposed at each side; a plunger having two slide pieces; a needle holder being caught and pulled by the plunger, and fitting a needle set. In use, the slide pieces of the plunger are confined by the slide confining portion of the elastic lashing member such that the plunger can not be turned. The plunger arrives at the bottom in the wake of injection such that the plunger is not confined by the elastic lashing member, and that the plunger can be thus turned to actuate the needle holder and drawn into the interior of the barrel by the plunger.