| 摘要 |
PROBLEM TO BE SOLVED: To improve a fluid injector by supplying air to a second chamber when starting an air pump, moving a movable wall to push drug from an outlet of a first chamber to a patient, and composing the air pump to supply set air quantity to the second chamber. SOLUTION: A slip seal is formed between a piston 16 provided with a seal 17 around an outer side end edge and the inner side of a container 1. The piston 16 composes a wall to part the container 1 into a lower chamber 18 and a size-changeable upper chamber 19. Liquid type drug is put in the lower chamber 18, and air is filled in the upper chamber 19. The piston 16 is connected to an actuating rod 20 extended in an axial direction of the container 1 upward. An injection needle 13 is pressed to the inside of a charging port, and the actuating rod 20 is pulled till the piston 16 is elongated to the maximum to be applied to a stop part 25, then liquid type drug is filled. By above simple and low-cost structure, this device can be manufactured with reliability. In addition, danger of choking can be reduced. |
