| 摘要 |
The present invention refers to the improvement developed in a dischargeable syringe totally made in plastic material, and with an internal safety mechanism that restrains its reuse after the first use. The syringe comprises a body (1), in whose interior is assembled an piston (2), driven by a rod (3), with a handle (31) at the free end. At the frontal end of the body (1) is a round tip (11) where a needle is assembled by adequate means. The piston (2) presents a head covered with sealing material, which is connected in a peg (21). Preferably, the piston (2) rotates freely on the peg (21) about a central axis (22). The rod (3) is independent from the piston (2) and has a tubular form, in whose end is fit the peg (21). This peg (21) has a lateral pin (23) that fits into a zigzag furrow (32), executed on the rod (3) internal end wall. As the advance and return movements of the piston (2) are executed inside the syringe body (1), in accordance with the recommended medical procedure, the pin of the peg (23) slides inside the piston furrow (32) until it escapes through the opening of the furrow (33). At this moment, the piston (2) gets free from the rod (3), not being more possible its connection. Even if the user tries to perform the inverse movements, the peg (21), due to its rotation, will not allow this movement. If the rod (3) is pulled, the piston (2) will remain immobile at the bottom of the syringe body (1), not allowing to uptake a new quantity of liquid. |
