Image forming apparatus

1. An image forming apparatus comprising:

a housing having an opening;

a drum cartridge mountable and demountable through the opening, the drum cartridge having a photosensitive drum rotatable about a first axis extending in an axial direction;

a toner cartridge mountable and demountable to and from the drum cartridge, the toner cartridge being capable of accommodating toner therein;

a first cover rotatable about a second axis extending in the axial direction and rotatable between a closed position at which a part of the opening is covered and an opened position at which a part of the opening is opened; and

a second cover in alignment with the first cover in the axis direction, the second cover rotatable about the second axis and being rotatable between a closed position at which a part of the remaining of the opening is covered and an opened position at which a part of the remaining of the opening is opened,

wherein, in a state in which the first cover is located at the opened position and the second cover is located at the opened position, the drum cartridge and the toner cartridge are allowed to be mounted and demounted through the opening,

wherein, in a state in which the first cover is located at the opened position and the second cover is located at the closed position, the toner cartridge is allowed to be mounted and demounted to and from the drum cartridge through a part of the opening while the drum cartridge is remained to be mounted to the housing, and

wherein, in a state in which the first cover is located at the opened position and the second cover is located at the closed position, a part of the second cover contacts with the drum cartridge and prevents the drum cartridge to be mounted and demounted to and from the housing through a part of the opening.

2. The image forming apparatus according to claim 1 ,

wherein the first cover and the second cover are front covers of the image forming apparatus.

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

a second lock mechanism that switches the second cover located at the closed position between a locked state in which the second cover is locked to the housing and a non-locked state in which the second cover is not locked to the housing.

4. The image forming apparatus according to claim 3 further comprising:

a first lock mechanism that switches the first cover located at the closed position between a locked state in which the first cover is locked to the housing and a non-locked state in which the first cover is not locked to the housing.

5. The image forming apparatus according to claim 4 further comprising:

a controller that is configured to:

determine that the toner cartridge is to be replaced; and

set the first lock mechanism to the non-locked state and set the second lock mechanism to the locked state based on determining that the toner cartridge is to be replaced.

6. The image forming apparatus according to claim 5 ,

wherein the controller is configured to:

determine that the drum cartridge is to be replaced; and

set the first lock mechanism to the non-locked state and set the second lock mechanism to the non-locked state based on determining that the drum cartridge is to be replaced.

7. The image forming apparatus according to claim 5 ,

wherein the controller is configured to:

determine that the image forming apparatus is in a paper jam state; and

set the first lock mechanism to the non-locked state and set the second lock mechanism to the non-locked state based on determining that the image forming apparatus is in the paper jam state.

8. The image forming apparatus according to claim 3 further comprising:

a third lock mechanism that switches the first cover between a locked state in which the first cover is locked to the second cover and a non-locked state in which the first cover is not locked to the second cover.

9. The image forming apparatus according to claim 8 further comprising:

a controller that is configured to:

determine that the toner cartridge is to be replaced; and

set the second lock mechanism to the locked state and set the third lock mechanism to the non-locked state based on determining that the toner cartridge is to be replaced.

10. The image forming apparatus according to claim 9 ,

wherein the controller is configured to:

determine that the drum cartridge is to be replaced; and

set the second lock mechanism to the non-locked state and setting the third lock mechanism to the locked state based on determining that drum cartridge is to be replaced.

11. The image forming apparatus according to claim 9 ,

wherein the controller is configured to:

determine that the image forming apparatus is in a paper jam state; and

set the second lock mechanism to the non-locked state and set the first lock mechanism to the locked state based on determined that the image forming apparatus is in the paper jam state.

12. The image forming apparatus according to claim 3 further comprising:

a controller that is configured to:

determine that the toner cartridge is to be replaced; and

set the second lock mechanism to the locked state based on determining that the toner cartridge is to be replaced.

13. The image forming apparatus according to claim 12 ,

wherein the controller is configured to:

determine that the drum cartridge is to be replaced; and

set the second lock mechanism to the non-locked state based on determining that the drum cartridge is to be replaced.

14. The image forming apparatus according to claim 12 ,

wherein the controller is configured to:

determine that the image forming apparatus is in a paper jam state; and

set the second lock mechanism to the non-locked state based on determining that the image forming apparatus is in the paper jam state.