Fused filament fabrication system and method

1. A fused filament fabrication system comprising:

a drive gear coupling to a motor during operation, the drive gear selectively operatively engaging first or second sets of idler gears during operation of the system; and

first and second filaments for the selective passage of material to corresponding first and second extruders, the first filament being positioned between said first idler gear shaft and idler bearings and said second filament being positioned between said second idler gear shaft and idler bearings, wherein said selectively operatively engaging said first or second idler gears is achieved by changing the rotational direction of said drive gear.

2. The system of claim 1 wherein said selectively operatively engaging one of said first or second idler gears is achieved by an actuation device.

3. The system of claim 1 wherein the motor coupled to said drive gear provides both movement of the system along a linear rail and operable rotation of said drive gear.

4. The system of claim 1 further comprising a latch coupled to an actuation device which selectively allows the drive gear to remain engaged with said first or second idler gears during changing of rotational direction of said drive gear, to allow for filament retraction.

5. A fused filament fabrication system comprising:

a drive gear coupling to a motor during operation, the drive gear selectively operatively engaging first or second idler gears during operation of the system;

first and second filaments for the selective passage of material to corresponding first and second extruders, the first filament being positioned between said first idler gear shaft and a first idler bearing and said second filament being positioned between said second idler gear shaft and a second idler bearing; and

said system during use dispensing material from said first filament when said first idler gear is engaged by said drive gear while said second filament remains free from dispensing, and said system during use dispensing material from said second filament when said second idler gear is engaged by said drive gear while the first filament remains free from dispensing, wherein said selectively operatively engaging one of said first or second idler gears is achieved by changing the rotational direction of said drive gear.

6. The system of claim 5 wherein said selectively operatively engaging one of said first or second idler gears is achieved by an actuation device.

7. The system of claim 5 wherein the motor coupled to said drive gear provides both movement of the system along a linear rail and operable rotation of said drive gear.

8. The system of claim 5 further comprising a latch coupled to an actuation device which selectively allows the drive gear to remain engaged with said first or second idler gears during changing of rotational direction of said drive gear, to allow for filament retraction.

9. A fused filament fabrication system comprising:

a drive gear coupling to a motor during operation, the drive gear selectively operatively engaging first or second sets of idler gears during operation of the system, wherein said selectively operatively engaging said first or second idler gears is achieved by changing the rotational direction of said drive gear;

first and second filaments for the selective passage of material to corresponding first and second extruders, the first filament being positioned between said first idler gear, a first idler shaft, and a first idler bearing and said second filament being positioned between said second idler gear, a second idler shaft, and a second idler bearing;

a latch coupled to an actuation device for selectively controlling the selective engagement and release of said first and second idler gears during the change of directional rotation of said drive gear such that retraction of material in said first and second filaments is controlled; and

said system during use dispensing material from said first filament when said first idler gear is engaged by said drive gear while the said second filament remains free from dispensing, and said system during use dispensing material from said second filament when said second idler gear is engaged by said drive gear while the first filament remains free from dispensing.

10. The system of claim 9 wherein said selectively operatively engaging one of said first or second idler gears is achieved by an actuation device.

11. The system of claim 9 wherein the motor coupled to said drive gear provides both movement of the system along a linear rail and operable rotation of said drive gear.

12. A fused filament fabrication system comprising:

a drive gear coupling to a motor during operation, the drive gear selectively operatively engaging a first set of idler gears responsive to a rotation of the drive gear in a first direction and a second set of idler gears responsive to the rotation of the drive gear in a second direction during operation of the system, wherein the first set of idler gears comprises a first idler gear and a first filament idler bearing and the second set of idler gears comprises a second idler gear and a second filament idler bearing; and

first and second filaments for the selective passage of material to corresponding first and second extruders, the first filament being positioned between said first idler gear shaft and the first filament idler gear and said second filament being positioned between said second idler gear shaft and said second filament idler bearings.

13. The system of claim 12 wherein said selectively operatively engaging one of the first set of idler gears or the second set of idler gears is achieved by an actuation device.

14. The system of claim 12 further comprising the motor coupled to said drive gear, the motor providing movement of the system along a linear rail.

15. The system of claim 12 further comprising the motor coupled to said drive gear, the operably rotating said drive gear.

16. The system of claim 12 further comprising a latch coupled to an actuation device which selectively allows the drive gear to remain engaged with the first idler gear during a rotation of the drive in the second direction and remain engaged with the second idler gears during the rotation of said drive gear in the second direction, to allow for a retraction of the first filament.

17. The system of claim 12 further comprising a latch coupled to an actuation device which selectively allows the drive gear to remain engaged with the second idler gear during a rotation of the drive in the first direction and remain engaged with the first idler gears during the rotation of said drive gear in the first direction, to allow for a retraction of the second filament.