TH83097A - Prefabricated machine for making syringes - Google Patents

Abstract

The DC60 syringe consists of a cylinder (1) with a piston (7) that is slidingly locked and sealed to the cylinder in order to provide an automatic self-destruct system until this syringe is usable only once. It is rendered unusable after one normal use. The cylinder (1) has a trajectory of obstructions on the inner surface of the cylinder wall in the form of grooves (10,11) or protrusions (29), and the piston (7) has a locking trajectory (17, 20) which operates by locking into the grooves (10, 11) or protrusions (29) upon piston retraction (7) to prevent further recoil. The locking trajectories (17, 20) are provided on the head of the piston (7) adjacent to the flexible sealing cover (15). The locking trajectories may consist of a pair of barbs (17) or a cross-shaped disc (20). The syringe consists of a cylinder (1) with a piston (7) that is slidingly locked and sealed to the cylinder in order to provide an automatic self-destruct system. Until this syringe is usable only once, it will be rendered unusable after one normal use. The cylinder (1) will have a trajectory that obstructs the inner surface of the cylinder in the form of a groove (10, 11) or protrusion (29), and the piston (7) will have a selector trajectory (17, 20) which will act by locking into the groove (10, 11) or protrusion (29) upon piston retraction (7) to prevent further retraction. The locking trajectories (17, 20) are provided on the head of the piston (7) adjacent to the flexible sealing cover (15). The locking trajectories may consist of a pair of barbs (17) or a cross-shaped disc (20).

Claims (8)

1. A finished instrument for making a one-piece syringe piston (7) for sliding in the syringe cylinder (1) and having locking trajectories (17, 20) for engaging with the obstructing trajectories (10, 11, 29) in the inner wall of the cylinder. The finished instrument consists of two casting parts, each part (30) supporting the indentation of a portion of the piston (7) in such a way that the two parts work together to form the entire piston. It is characterized by each part (30) having an insert (36) that supports the indentation for the locking trajectories (17, 20) for the piston portion, respectively. The insert (36) is attached in a removable manner to the said part (30). 2. The instrument pursuant to claim 1, where the insert (36) shall be installed at the existing dividing line (34) in the said instrument. 3. The finished instrument under claim 1 or 2, in which each insert (36) is secured to the instrument section (30) by a bolt inserted into an opening aligned in the insert (36) and the instrument section (30). 4. The completed instrument under claim 1 or 2, in which each interlocking part (36) shall be secured by the compacting part (37). 5. The instrument pursuant to claim 1, in which part of the instrument (30) shall be provided with a cavity for receiving the insert (36). 6. An instrument pursuant to any of the claims in Sections 1 through 5, in which each of these (36) is comprised of one or more plates (38, 39). 7. An insert (7) is used in a finished machine for making a one-piece syringe piston, for sliding into the syringe cylinder (1), and has locking trajectories (17, 20) for engaging with the obstruction trajectories (10, 11, 29) in the inner wall of the cylinder. The finished machine consists of two casting parts, each (30) supporting the indentation of a portion of the piston (7) in such a way that the two parts work together to form the entire piston. It is characterized by the insert (36) supporting the indentations for the locking trajectories (17, 20) of the piston portion respectively, and is detachably attached to the corresponding part (30) of the machine. 8. An insert under claim 7, where this insert (36) shall consist of one or more plates (38, 39).