| abstract |
The present invention relates to a housing (10, 30, 40; 40 '); A piston rod (80) located inside the housing (10, 30, 40; 40 '); A drive member (70) permanently coupled to the piston rod (80); (10, 30, 40; 40 ') rotating in a first direction relative to the housing (10, 30, 40; 40' Amount setting member 50; And a power storage unit (100) for driving the driving member (70). The drive member 70 is configured to move from the dose setting position where the rotation of the drive member 70 to the housing 10, 30, 40; 40 'is restricted and from the housing 10, 30, 40, 40' Can be axially moved between dose dispense positions where the pump 70 is rotationally de-coupled. The power storage unit 100 includes a reverse-wound flat spiral spring 100 having a first end attached to the first spool 101 and a second end attached to the second spool 102, One (102) is coupled to the drive member (70). |