Photoconductive drum driving gear device usable with image forming apparatus

A photoconductive drum driving gear device usable with an image forming apparatus, comprising:

• a driving shaft;
• a driving gear to rotate with the driving shaft in connection with the driving shaft and meshed with a photoconductive drum gear of a process cartridge of the image of the image forming apparatus;
• and
• a connection unit to connect the driving gear and the driving shaft such that the driving gear rotates with respect to the driving shaft by a predetermined angle when mounting the process cartridge into a main body of the image forming apparatus.

A driving apparatus, comprising:

• a driving gear including a plurality of recesses therein;
• a driving shaft to transfer a driving power to the driving gear and having a plurality of connection projections extending therefrom to engage within respective ones of recesses of the driving gear;
• and
• an impact absorption member provided between at least one of the connection projections and an inner portion of the respective recess to absorb an impact applied to the driving gear while the driving shaft is stationary such that the driving gear rotates by a predetermined amount with respect to the driving shaft.

A driving gear device, comprising:

• a driving shaft formed with a plurality of protruding portions protruding from an end thereof, each protruding portion having a first width;
• a driving gear formed with a plurality of arc shaped accommodating portions corresponding with the plurality of protruding portions of the driving shaft to accommodate the plurality of protruding portions, each arc shaped accommodating portion having a second width larger than the first width to allow the respective protruding portions to slide between opposite walls of the arc shaped accommodating portions to rotate the driving gear with respect to the driving shaft;
• and
• a plurality of elastic members, each provided in one of the plurality of arc shaped accommodating portions between an inner wall thereof and the respective protruding portion accommodated therein to elastically bias the respective protruding portion toward an opposite wall of the arc shaped accommodating portion to control a direction of rotation of the driving gear with respect to the driving shaft.

An image forming apparatus comprising:

• a main body;
• a process cartridge installable in the main body, and comprising a photoconductive drum and a photoconductive drum gear to rotate the photoconductive drum, the photoconductive drum gear being formed with teeth on a surface thereof;
• a driving shaft installed in the main body to rotate with respect to the main body;
• and
• a driving gear connected to the driving shaft to rotate with the driving shaft, the driving gear formed with teeth on an outer surface thereof to align with the teeth of the photoconductive drum gear to transfer the rotation of the driving shaft to the photoconductive drum gear and rotatable with respect to the driving shaft at a predetermined angle to provide alignment between the teeth of the photoconductive drum gear and the teeth of the driving gear upon impact therebetween before rotating with the drive shaft.