Developing apparatus

A developing apparatus mountable to an image forming apparatus, comprising:

• a developer bearing member bearing toner;
• a first chamber containing developer having the toner and a carrier;
• a second chamber containing the developer, and configured to form a circulation path of the developer in combination with the first chamber;
• a first feeding member arranged in the first chamber and feeding the developer inside the first chamber in a first direction;
• a second feeding member arranged in the second chamber and feeding the developer inside the second chamber in a second direction opposite to the first direction;
• a first communication part through which the developer is transferred from the first chamber to the second chamber;
• a second communication part through which the developer is transferred from the second chamber to the first chamber;
• a feeding path having a discharging port through which the developer is discharged, and communicating with the first chamber on a downstream side relative to the first communication part in the first direction to feed the developer toward the discharging port;
• a sealing part sealing the developer inside the developing apparatus before usage of the developing apparatus starts;
• a feeding path sealing part arranged in the sealing part, and sealing the feeding path on an upstream side relative to the discharging port in the first direction before usage of the developing apparatus starts;
• and
• an unsealing mechanism receiving a driving force from the image forming apparatus and unsealing the sealing part.