| 摘要 |
<p>A dose delivery device is disclosed wherein a dose can be set rotating a dose setting member (3), whereby a push button (3) is elevated from one end of the device a distance proportional to the set dose from a position fixed relative to the housing, and wherein the set dose can then be injected by pressing the push button back to its non-elevated position, through which motion a piston rod (7) will move the same or a different distance due to a gearing mechanism being provided between the push button and the piston rod. The gearing mechanism comprises at least a first and a second thread on one or more parts that are rotationally coupled to each other, the first thread engaging a driver, the second thread engaging an element rotationally locked to the driver, one of the threads of the gearing mechanism being left-handed and other one being right-handed.</p> |
