Magnet including a non-rotatable shaft engaged with a through hole at a lateral end

A process cartridge comprising:

• an image bearer configured to bear a latent image;
• and
• a developing device combined with the image bearer into a unit, the developing device configured to contain a developer,
• the developing device comprising:
• a developing roller configured to bear the developer and the developing roller including a magnet including a plurality of magnetic poles arranged in a circumferential direction of the magnet;
• a developer supplying rotator disposed opposite the developing roller, the developer supplying rotator configured to rotate in a predetermined direction to supply the developer onto the developing roller;
• a compartment accommodating the developer supplying rotator;
• a first developing side plate including a through hole configured to position the magnet in the circumferential direction of the magnet;
• a seal mounted on the first developing side plate;
• a second developing side plate supporting the developer supplying rotator rotatably;
• and
• a sheet member configured to separate the developing roller from the developer supplying rotator, the sheet member configured to form an enclosed space that contains the developer in the compartment, the sheet member configured to be removed from the developing device,
• wherein the first developing side plate includes a sheet opening disposed opposite the second developing side plate, the sheet opening through which a part of the sheet member protrudes toward an outside of the developing device,
• wherein the magnet includes a non-rotatable shaft,
• wherein the non-rotatable shaft is disposed at a lateral end of the magnet and the non-rotatable shaft engaged the through hole, and
• wherein the seal is mounted on the sheet opening of the first developing side plate and the seal presses against the second developing side plate.

An image forming apparatus comprising:

• an image bearer configured to bear a latent image;
• and
• a developing device configured to be removed from the image forming apparatus, the developing device configured to contain a developer,
• the developing device including:
• a developing roller configured to develop the latent image formed on the image bearer with the developer and the developing roller including a magnet including a plurality of magnetic poles arranged in a circumferential direction of the magnet;
• a developer supplying rotator disposed opposite the developing roller, the developer supplying rotator configured to rotate in a predetermined direction configured to supply the developer onto the developing roller;
• a compartment accommodating the developer supplying rotator;
• a first developing side plate including a through hole configured to position the magnet in the circumferential direction of the magnet;
• a seal mounted on the first developing side plate;
• a second developing side plate supporting the developer supplying rotator rotatably;
• and
• a sheet member configured to separate the developing roller from the developer supplying rotator, the sheet member configured to form an enclosed space that contains the developer in the compartment, the sheet member configured to be removed from the developing device,
• a seal mounted on the first developing side plate,
• wherein the first developing side plate includes a sheet opening disposed opposite the second developing side plate, the sheet opening through which a part of the sheet member protrudes toward an outside of the developing device,
• wherein the magnet includes a non-rotatable shaft,
• wherein the non-rotatable shaft is disposed at a lateral end of the magnet and is engaged the through hole, and
• wherein the seal is mounted on the sheet opening of the first developing side plate and the seal presses against the second developing side plate.