Image forming apparatus

1. An image forming apparatus, comprising:

an apparatus main body including an image forming unit that forms an image on a medium and a cover member, the image forming unit and the cover member being independently rotatably attached to the apparatus main body, the cover member including:

a developer accommodation part that supplies a developer to the image forming unit,

a developer supply duct that is disposed between the image forming unit and the developer accommodation part such that the developer reaches the image forming unit through the developer supply duct,

a shutter member that reciprocates between an open position and a closed position wherein the developer is provided to the image forming unit through the shutter member when the shutter member is at the open position, and the developer is blocked with the shutter member when the shutter member is at the closed position,

a first operation part that

comprises an engaging part, which engages with the image forming unit, and

moves the shutter member either to the open position or to the closed position, wherein

the first operation part causes the engaging part to disengage from the image forming unit when the shutter member exists at the closed position,

in a disengaged state in which the engaging part is disengaged from the image forming unit, the cover member rotates relative to the apparatus main body and independently from the image forming unit.

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

the first operation part moves the shutter member toward a position where the engaging part disengages an engagement with the image forming unit,

the shutter member moves from the open position toward the closed position as being linked with the first operation part, and

the engaging part moves to the position where the engaging part disengages the engagement after the shutter member moves from the open position toward the closed position, and reaches the closed position.

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

the shutter member moves in a shutter closing direction, and

after reaching the closed position, the shutter member maintains a developer supply blockage state to block the developer supply duct even after the image forming unit and the engaging part disengage.

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

the shutter member moves in a shutter closing direction, and

after reaching the closed position, the shutter member does not move in the shutter closing direction by a force by which the first operation part is moved, and maintains a developer supply blockage state to block the developer supply duct even after the image forming unit and the engaging part disengage.

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

the first operation part moves in a front-back direction with respect to the image forming apparatus, and the shutter member moves in a different direction from the front-back direction.

6. The image forming apparatus according to claim 1 , further comprising:

the cover member covers one side of the apparatus main body, and

the image forming unit is rotatable with respect to the apparatus main body together with the cover member in an engaged state in which the engaging part is engaged with the image forming unit.

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

the cover member rotates around a rotation shaft,

the image forming unit is installed on the rotation shaft such that the cover member and image forming unit coaxially rotates, and

the engaging part and the rotation shaft are disposed sandwiching the image forming unit.

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

the image forming unit comprises

a development unit that forms an image on the medium, and

a holding unit that holds the development unit, and

the engaging part engages with the holding unit of the image forming unit.

9. The image forming apparatus according to claim 1 , further comprising:

a second operation part that opens or closes the cover member, wherein

the first operation part is in contact with the second operation part while the engaging part is in a transition state that is defined as being positioned from a position engaged with the image forming unit to a position disengaged from the image forming unit.

10. The image forming apparatus according to claim 9 , wherein

the second operation part moves rotating along a prescribed rotational trajectory, and

the first operation part moves linearly in a front-back direction, and enters the rotational trajectory in the transition state, restricting the movement of the second operation part.

11. An image forming apparatus, comprising:

an image forming unit that forms an image on a medium,

a developer accommodation part that supplies a developer to the image forming unit,

a developer supply duct that is disposed between the image forming unit and the developer accommodation part such that the developer reaches the image forming unit through the developer supply duct,

a shutter member that reciprocates between an open position and a closed position wherein the developer is allowed to pass through the shutter member when the shutter member is at the open position, and the developer is blocked with the shutter member when the shutter member is at the closed position,

a first operation part that

comprises an engaging part, which engages with the image forming unit, and

moves the shutter member either to the open position or to the closed position, wherein

the first operation part causes the engaging part to disengage from the image forming unit when the shutter member exists at the closed position, and

the first operation part moves in a front-back direction with respect to the image forming apparatus, and the shutter member moves in a different direction from the front-back direction.