Developing cartridge, process unit, and image forming apparatus

A process unit, comprising:

• a developing cartridge including a developing agent containing chamber that contains a developing agent;
• and
• a photosensitive member frame that supports a photosensitive member and is formed with a process accommodating portion that accommodates the developing cartridge, and wherein the developing cartridge includes:
• a drive gear that inputs a drive force thereto;
• and
• a detection gear that is formed with a determination member that irreversibly moves from a unused position where the detection gear does not engage with the drive gear, to a used position where the detection gear does not engage with the drive gear, through a drive force transmitting position where the detection gear engages with the drive gear, wherein the photosensitive member frame includes a receiving portion that is formed in association with a movement path of the determination member and receives the determination member.

An image forming apparatus, comprising:

• a main accommodating portion that removably accommodates therein a process unit including a developing cartridge and a photosensitive member frame formed with a process accommodating portion that accommodates the developing cartridge, the photosensitive member frame supporting a photosensitive member;
• wherein the developing cartridge includes:
• a developing agent containing chamber that contains a developing agent;
• a drive gear that inputs a drive force thereto;
• and
• a detection gear that is formed with a determination member that irreversibly moves from a unused position where the detection gear does not engage with the drive gear, to a used position where the detection gear does not engage with the drive gear, through a drive force transmitting position where the detection gear engages with the drive gear;
• and wherein the image forming apparatus further comprises:
• a contacted member, provided at the main accommodating portion, that contacts the determination member and moves the detection gear from the unused position to the drive force transmitting position when the process unit is accommodated in the main accommodating portion.