Drive mechanism for electrophotographic image forming apparatus

A drive mechanism of an electrophotographic image forming apparatus to form an image on an image transfer body, the drive mechanism comprising:

• a first driving part, comprising:
• an image forming device to form the image on the image transfer body, a conveyor to convey the image transfer body to the image forming device, image on the image transfer body;
• a first driving motor to drive the conveyor and the image forming device, by rotating unidirectionally, and
• a first power transmitter to transmit power generated by the first driving motor to the conveyor and the image forming device;
• and
• a second driving part, comprising:
• a fixing device to fix the image on the image transfer body,
• a delivery roller to discharge the image transfer body having the image fixed thereon,
• a conveying roller to convey the discharged image transfer body for duplex printing,
• a second driving motor to drive the fixing device, the delivery roller, and the conveying roller by rotating bidirectionally, and
• a second power transmitter to transmit power generated by the second driving motor to the fixing device, the delivery roller, and the conveying roller;
• wherein the second power transmitter comprises a unidirectional power transmitting unit to prevent the power generated by the second driving motor from being transmitted to the fixing device and the delivery roller when the second driving motor rotates in a duplex printing direction in which the image transfer body is transferred.

A drive mechanism of an electrophotographic image forming apparatus to form an image on a plurality of image transfer bodies, the electrophotographic image forming apparatus comprising a paper feeding cassette to stack the image transfer bodies therein, a pickup roller, a transfer roller, a registration roller, first and second duplex rollers, a fixing roller, first and third delivery rollers, and an OPC (Organic Photo Conductor) drum, the drive mechanism comprising:

• a first driving motor including a pinion;
• a first gear train, engaged with the pinion of the first driving motor to transmit power of the first driving motor to the pickup roller to thereby separate and pick up the image transfer bodies stacked in the paper feeding cassette one by one, to the transfer roller, the transfer roller conveying the picked-up image transfer body in a printing direction, and to the registration roller, the registration roller aligning and conveying the image transfer body conveyed from the transfer roller;
• a second gear train, engaged with the pinion of the first driving motor to transmit the power of the first driving motor to the OPC drum, the OPC drum to transmit the image to a front page of the image transfer body conveyed by the registration roller, and to the second duplex roller, the second duplex roller to convey the front page transmitted image transfer body to the transfer roller;
• a second driving motor including a pinion;
• a third gear train, engaged with the pinion of the second driving motor, to transmit power of the second driving motor to the fixing roller, the fixing roller to fix the transmitted image onto the image transfer body, and to the first delivery roller, the first delivery roller to deliver the image transfer body from the fixing roller to the third delivery roller;
• and
• a fourth gear train, engaged with the pinion of the second driving motor, to transmit the power of the second driving motor to the third delivery roller, the third delivery roller to deliver the image transfer body received from the first delivery roller to an outside.

An electrophotographic image forming apparatus to form images on first and second sides of a transfer body, comprising:

• a developer to form the images on the transfer body;
• a first delivery roller to convey the image formed transfer body;
• a third delivery roller to receive the image formed transfer body from the first delivery roller;
• a first duplex roller to receive the transfer body from the third delivery roller and return the received transfer body to the developer;
• a first drive unit to drive the developer;
• and
• a second drive unit to drive the first and third delivery rollers and the first duplex roller.