| 摘要 |
<p>A pen-shaped syringe with automatic needle insertion has an injection system integrally displaceable in a housing (1) and comprising a basic part (17) carrying a medicine reservoir with a hypodermic needle at its distal end, and a dosing mechanism with a carrier (34) engaging a cogged piston rod (35), the carrier being coupled to a dose spindle (25) in a rotatable but not displaceable way. The dose spindle (25) is provided with a thread engaging a thread in a sequence part (20) having protrusions (22) engaging slots (21) in the basic part (17) to allow a limited axial movement of the parts (20, 17) in relation to each other, the extent of the movement being defined by the rotational position of the dose spindle (25). A spring (23) is compressed between the basic part (17) and the housing (1) when the basic part is moved in the proximal direction by exerting a cocking force on the sequence part (20), which part after having performed the set limited axial movement in relation to the basic part (17) carries this basic part against the force of the spring (23).</p> |
