Medication delivery pen having improved dose delivery features
US5279585A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 4, 1992 |
| Grant date | Jan 18, 1994 |
| Priority date | — |
| Expiry date | Feb 4, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M2205/581
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An injection device is provided for injecting fluids such as insulin within body tissue. The device includes a housing, a piston rod movably mounted within the housing, and a dose setting mechanism for controlling the movement of the piston rod with respect to a fluid containing cartridge removably positioned within the housing. The dose setting mechanism includes a units counter ring and a tens counter ring. A transmission key is provided for selectively coupling the units and tens counter rings so that they rotate together only during selected portions of the dose setting procedure. The piston rod includes a plunger and a lead screw slidably positioned within the plunger. The plunger and lead screw are coupled by a pair of half nuts. The half nuts may be uncoupled from the lead screw in order to allow it to slide freely with respect to the plunger. A new cartridge may accordingly be installed quickly and easily as the lead screw is easily displaced by a new cartridge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.