| 摘要 |
Handheld drug injection device (10) for setting and dispensing of a dose of a medicament, having a housing (20) extending in an axial direction (1, 2) and a dose setting and drive mechanism (3) comprising: —a rotatable dose setting member (50) in a sidewall of the housing and engaging two dose indicating wheels (54,56), —a drive member (70) axially displaceable relative to a drive spindle (80) and the housing against the action of a spring element (78) during dose setting and having a sleeve-shaped part (72) being threadedly engaged with the drive spindle (80) to form a spindle gear, and having a rack portion (71) engaged with a gear wheel (58) of the dose setting member, —the drive spindle (80) being linked on its proximal end to a ratchet mechanism (140,150) which is releasable via an axially shiftable trigger button (40) for dose dispensing, and on its distal end via a pinion (86) to a —drive sleeve (90), the latter being axially shiftable to form a clutch for engagement with —a threaded piston rod (120), which engages a piston (14) of a cartridge (12) to displace the piston (14) in a distal axial direction (1), the trigger button (40) releasing the ratchet holding the drive spindle (80) to free it for rotation, and closing the clutch between drive sleeve (90) and piston rod (120), such that the drive spring (78) can push the drive member (70) forward, thereby rotating the spindle (80), which in turn rotates the drive sleeve (90), which in turn produces spiral forward movement of the piston rod (120). A dose limiter element (130) is also included between piston rod and coaxial drive sleeve. |
| 主权项 |
1. A drive mechanism of a drug delivery device for setting and dispensing of a dose of a medicament, the mechanism comprising:
a housing (20) extending in an axial direction (1, 2), a piston rod (120) to operably engage with a piston (14) of a cartridge (12) to displace the piston (14) in a distal axial direction (1), a drive spindle (80) operably engageable with the piston rod (120) during dose dispensing, a drive member (70) axially displaceable relative to the drive spindle (80) against the action of a spring element (78) during dose setting and being threadedly engaged with the drive spindle (80) to form a spindle gear. |
