Mechanical transmission
AssigneeInternational Business Machines Corporation
InventorRichard Hunter Harris
Life of this patent
Estimating the term…
Abstract
An apparatus to drive a ribbon carrying a printing medium in an impact printer is implemented. The apparatus accommodates manual tightening of the ribbon by decoupling the drive motor from the ribbon cartridge without use of a clutch mechanism. A gear train effecting the required speed reductions between a drive motor and the ribbon cartridge spool also implements the decoupling. Reliability of the ribbon drive is improved thereby, and manufacturing and assembly costs are reduced over ribbon drives now used in impact printers.
Claims22
A mechanical transmission comprising:
- a worm gear adapted for receiving a drive means for rotating said worm gear;
- a worm gear frame, said worm gear frame pivotally disposed about said worm gear;
- a compound worm gear, said compound worm gear being rotatably supported by said worm gear frame, wherein said compound worm gear includes a worm gear portion and a pinion gear portion, said pinion gear portion engaging said worm gear;
- and
- a pinion having a pinion gear at a first end and an opposite end adapted for engaging an output shaft, said pinion gear engaging said worm portion of said compound worm gear.
A mechanical transmission comprising:
- a worm gear adapted for receiving a drive means for rotating said worm gear;
- a compound worm gear, wherein said compound worm gear includes a worm gear portion and a pinion gear portion, said pinion portion engaging said worm gear, said compound worm gear including a first journal adjacent to said worm gear portion, and a second journal adjacent to said pinion gear portion;
- a worm gear frame, said worm gear frame pivotally disposed about said worm gear, wherein said worm gear frame further includes a base having an opening through which said worm gear passes, a first upright located at an end of said base, a second upright located at an opposite end of said base, and wherein said first upright includes a first bearing rotatably supporting said first journal of said compound worm gear, and said second upright includes a second bearing rotatably supporting said second journal of said compound worm gear;
- and
- a pinion having a pinion gear at a first end and an opposite end adapted for engaging a driven load, said pinion gear engaging said worm gear portion of said compound worm gear.
A mechanical transmission comprising:
- a first gear adapted for operating with a drive means;
- a second gear engaging said first gear and adapted for pivoting about said first gear;
- a third gear attached to said second gear whereby said second gear pivots therewith about said first gear;
- and
- a fourth gear for engaging with said third gear, wherein said fourth gear and said third gear engage and disengage in response to said pivoting about said first gear, said fourth gear including a portion adapted for engaging a driven load, said driven load having a second means for operation, and
- wherein said pivoting of said third gear and said second gear about said first gear comprises:
- a pivoting in a first direction;
- and
- a pivoting in a second direction.
Dependencies are inferred from the claim text.