System for opening and closing a resealable cartridge

1. A system for opening and closing a resealable cartridge having a tray and a flexible cover resealably engaged with the tray, the system comprising:

a base for receiving the tray of the cartridge;

a roller shaft having means for engaging the cover of the cartridge;

positioning means operably connected to the roller shaft to affect positioning of the roller shaft relative to the cartridge between a first position wherein the roller shaft is spaced from the cartridge and a second position different from the first position wherein the roller shaft is not spaced from the cartridge;

a motor for rotating the roller shaft in a first rotational direction to wind the cover about the roller shaft, thereby removing at least a portion of the cover from the tray, and for rotating the roller shaft in a second rotational direction to unwind the cover from the roller shaft thereby resealably engaging the cover with the tray; and

at least one constant force spring attached to the base and applying a force in the second rotational direction to the roller shaft.

2. The system of claim 1 , wherein the positioning means further includes a cam.

3. The system of claim 2 , wherein the positioning means further includes a cam nest.

4. The system of claim 3 , wherein the system further includes at least one torsion spring biasing the cam toward the cam nest.

5. The system of claim 1 , further comprising:

first sensing means positioned at a first location for sensing a first position of the roller shaft wherein the roller shaft is spaced from the cartridge; and

second sensing means positioned at a second location different than the first location for sensing a second position of the roller shaft indicative of the removal of at least a portion of the cover from the tray.

6. The system of claim 5 , wherein the first and second sensing means are activated by the opening and closing system.

7. The system of claim 1 , further comprising a pinch roller attached to the base and biased toward the roller shaft to supply a force between the roller shaft and the cartridge.

8. A system for opening and closing a resealable cartridge having a tray and a flexible cover resealably engaged with the tray, the system comprising:

a base for receiving the tray of the cartridge;

a roller shaft having means for engaging the cover of the cartridge;

a motor for rotating the roller shaft in a first rotational direction to wind the cover about the roller shaft, thereby removing at least a portion of the cover from the tray, and for rotating the roller shaft in a second rotational direction to unwind the cover from the roller shaft thereby resealably engaging the cover with the tray;

positioning means operably connected to the roller shaft to affect positioning of the roller shaft, the positioning means positioning the roller shaft in a first position spaced from the cartridge and disposed intermediate the base and the cover; and

at least one constant force spring attached to the base and applying a force in the second rotational direction to the roller shaft.

9. The system of claim 8 , wherein the positioning means further includes a cam operably connected to the roller shaft.

10. The system of claim 8 , further comprising a pinch roller attached to the base and biased toward the roller shaft to supply a force between the roller shaft and the cartridge.

11. The system of claim 8 , further comprising:

first sensing means positioned at a first location for sensing a first position of the roller shaft wherein the roller shaft is spaced from the cartridge; and

second sensing means positioned at a second location different than the first location for sensing a second position of the roller shaft indicative of the removal of at least a portion of the cover from the tray.

12. The system of claim 11 , wherein the first and second sensing means are activated by the opening and closing system.