| 摘要 |
A cylinder-piston unit, with at least one cylinder accommodating an injection solution and having an outlet opening, and with at least one piston. The cylinder, or a component mounted upstream of the cylinder, has an end face from which, during correct emptying of the cylinder-piston unit, a short cannula protrudes, which has an outlet opening at its free end. The outlet opening has a surface with a border which has a point near the bottom or an edge near the bottom. The point near the bottom or the edge near the bottom lies 0.15-0.3 mm away from the end face or the front-most point or edge thereof. A cylinder-piston unit is developed which is intended for a disposable injector and which is suitable for virtually painless penetration of the human skin, among other reasons for the administration of highly viscous injection solutions. |
| 主权项 |
1. Cylinder-piston unit (10), with at least one cylinder (20) accommodating an injection solution (1) and having an outlet opening (71), and with at least one piston (80), a piston actuating rain (7) actuating the at least one piston (80), the improvement which comprises:
the cylinder (20) has a bottom portion (33), on which a short cannula (61) is arranged congruent to the centre line (5) of the cylinder-piston unit (10), the bottom portion (33) of the cylinder (20) has a front end face (46), an elastomer adhesive disc (110), which is displaceable in the direction of a center line (5) of the cylinder-piston unit (10) between and an installation position (111) and an application position (112) is slidably arranged on the short cannula (61) and/or on the bottom portion (33), the bottom portion (33) has an annular web (51), which extends forward in a continuation of the outer wall (32) of the cylinder (20), the annular web (51) encloses a receiving space (53) for the elastomer disc (110), the elastomer disc (110) slidable within the receiving space (53), the elastomer disc (110) in the installation position (111) occupying a front area of the receiving space (53) and the short cannula (61) penetrating a predetermined portion of the elastomer disc (110), but not fully through the elastomer disc (110), in the application position (112) the elastomer disc (110) fully occupying the receiving space (53), the elastomer disc (110) in the application position (112) bearing on the front end face (46) of the bottom portion (33) and simultaneously protruding a predetermined distance beyond the annular web (51), the elastomer disc (110) having an end face (113) mounted upstream of the cylinder (20), from which, during correct emptying of the cylinder-piston unit (10) in the application position (112), the short cannula (61) protrudes, the short cannula (61) has an outlet opening (71) at its free end, the short cannula (61) in fluid communication with the cylinder (20); the outlet opening (71) has a surface with a border (72) which has a point (74) near the bottom or an edge (76) near the bottom, and the point (74) near the bottom or the edge (76) near the bottom lies 0.15-0.3 mm away from the end face (113) of the elastomer disc (110) or the front-most point or edge (44) thereof. |
