Image forming apparatus and developer container removably connected thereto

1. An image forming apparatus comprising:

a developer container which is removably connected to an image forming apparatus main body and which includes:

a cylindrical container body in which developer is contained;

a developer discharge port which is formed at one end of the container body and through which the developer inside the container body is discharged; and

a shutter which is rotatable through a predetermined angle relative to the container body and which is so fitted as to restrict rotation relative to the container body at both ends of the predetermined angle, the shutter having an opening formed in part of a surface thereof facing the developer discharge port,

the container body being rotated in a circumferential direction to cause the developer to be discharged through the developer discharge port;

a developer feeding mechanism which rotatable supports the developer container and which feeds the developer discharged through the developer discharge port to a developing device;

a drive mechanism which drives the developer container to rotate in a developer feeding direction; and

a torque limiter which is provided on the developer feeding mechanism and which engages with the shutter when the developer container is connected to the image forming apparatus main body,

the image forming apparatus being configured such that

when the developer container is rotated in the developer feeding direction, while the torque limiter keeps the shutter stationary, the container body rotates through a predetermined angle to open the developer discharge port, and as the developer container continues to be rotated, the shutter, while keeping the developer discharge port open, rotates together with the container body to allow the developer to be fed through the developer discharge port, and

when the developer container is rotated in a direction reverse to the developer feeding direction, while the torque limiter keeps the shutter stationary, the container body rotates through a predetermined angle in a reverse direction to close the developer discharge port.

2. The image forming apparatus according to claim 1 , wherein

the drive mechanism can drive the developer container also in a direction reverse to the developer feeding direction, the drive mechanism opening the developer discharge port when performing a developer feeding operation in which the drive mechanism rotates the developer container in the developer feeding direction, the drive mechanism closing the developer discharge port by rotating the developer container in the direction reverse to the developer feeding direction when stopping the developer feeding operation.

3. The image forming apparatus according to claim 1 , wherein

by manually rotating the developer container through a predetermined angle in the developer feeding direction, the developer container and the drive mechanism are engaged and fixed together and the developer discharge port is opened, and

by manually rotating the developer container through a predetermined angle in a direction reverse to the developer feeding direction, the developer container and the drive mechanism are disengaged from each other and the developer discharge port is closed.

4. A developer container removably connected to an image forming apparatus comprising:

a developer feeding mechanism which rotatably supports a developer container and which feeds developer discharged through a developer discharge port formed in the developer container to a developing device;

a drive mechanism which drives the developer container to rotate in a developer feeding direction; and

a torque limiter which is provided on the developer feeding mechanism and which, when the developer container is connected to an image forming apparatus main body, engages with a shutter which is rotatably fitted to a container body of the developer container and which has an opening formed in part of a surface thereof facing the developer discharge port,

the image forming apparatus being configured such that

when the developer container is rotated in the developer feeding direction, while the torque limiter keeps the shutter stationary, the container body rotates through a predetermined angle to open the developer discharge port, and as the developer container continues to be rotated, the shutter, while keeping the developer discharge port open, rotates together with the container body to allow the developer to be fed through the developer discharge port, and

when the developer container is rotated in a direction reverse to the developer feeding direction, while the torque limiter keeps the shutter stationary, the container body rotates through a predetermined angle in a reverse direction to close the developer discharge port,

the developer container comprising a container body, a developer discharge port, and a shutter,

the container body being cylindrical and containing the developer therein,

the developer discharge port being formed at one end of the container body and allowing the developer inside the container body to be discharged therethrough,

the shutter being fitted so as to be rotatable through a predetermined angle relative to the container body and having an opening formed in part of a surface thereof facing the developer discharge port, and

the container body being rotated in a circumferential direction to cause the developer to be discharged through the developer discharge port.

5. The developer container according to claim 4 , wherein

the shutter is a cylindrical member that is open at one end, the shutter having an inner diameter slightly greater than an outer diameter of the cylindrical container body, and a projection formed on an inner circumferential surface of the shutter engages with a cut formed in a predetermined area in an outer circumferential surface of the container body such that the shutter is rotatable relative to the container body within the area of the cut.

6. The developer container according to claim 4 , wherein

a helical transport rib is formed on an inner wall surface of the container body.

7. The developer container according to claim 4 , wherein

a cap is removably fitted to the container body at an end thereof opposite from the developer discharge port.