Image forming apparatus and control system

1. An image forming apparatus for forming an image using a replaceable image formation unit, comprising:

an abnormality signal input device configured to input a signal representing occurrence of abnormality in one of an output image and the image forming apparatus recognized by an operator;

a unit specifying device configured to specify a replacement unit to be replaced to resolve the abnormality upon receiving the signal from the abnormality signal input device;

a notification device configured to notify the operator of information related to the replacement unit in accordance with a result of the specification executed by the unit specifying device; and

a lock mechanism configured to lock and prohibit the replacement unit from being removed from the image forming apparatus, said lock mechanism including a moveable member, wherein a controller causes the moveable member to be disposed at a position that prohibits the replacement unit from being removed through an opening in the image forming apparatus while the replacement unit is aligned with the opening, and the controller causes the moveable member to be disposed at another position that allows the replacement unit to be removed through the opening in the image forming apparatus that is aligned with the replacement unit in response to the replacement unit being specified for replacement by the unit specifying device.

2. The image forming apparatus as claimed in claim 1 , further comprising:

an image formation device configured to form a toner image for image quality determination use on a transfer belt; and

an image reading device configured to read the toner image from the transfer belt for image quality determination use,

wherein said unit specifying device determines image quality of the toner image for image quality determination use based on the reading result and specifies a replacement unit to be replaced in accordance with the quality determination.

3. The image forming apparatus as claimed in claim 2 , wherein said image reading device includes a photo sensor.

4. The image forming apparatus as claimed in claim 2 , wherein said image reading device includes a scanner.

5. The image forming apparatus as claimed in claim 2 , wherein the transfer belt is configured to feed an image carrier through the image forming apparatus, and the toner image for the image quality determination use is not printed onto the image carrier.

6. The image forming apparatus as claimed in claim 2 , further comprising a controller configured to prevent a sheet feeding section from feeding sheets while the image formation device forms the toner image for image quality determination use on the transfer belt, the image reading device reads the toner image from the transfer belt for image quality determination use, and said unit specifying device determines image quality of the toner image based on the reading result.

7. The image forming apparatus as claimed in claim 1 , wherein said notification device notifies information related to the replacement unit including that the replacement unit is not present.

8. The image forming apparatus as claimed in claim 1 , wherein the unit specifying device is arranged within the image forming apparatus.

9. The image forming apparatus as claimed in claim 1 , wherein the image forming apparatus is connected to an external control apparatus, and wherein said unit specifying device is arranged in the control apparatus.

10. The image forming apparatus as claimed in claim 1 , wherein the replacement unit is a developer unit, a fixing unit, or an image formation unit.

11. The image forming apparatus as claimed in claim 1 , further comprising a plurality of replacement units, wherein the lock mechanism unlocks and enables detachment of only the replacement unit specified by the unit specifying device while other replacement units are locked and prevented from being detached from the image forming apparatus.

12. The image forming apparatus as claimed in claim 1 , further comprising a plurality of replacement units, wherein the lock mechanism unlocks and enables detachment of all of the plurality of replacement units in response to one of the plurality of replacement units being specified by the unit specifying device.

13. The image forming apparatus as claimed in claim 1 , wherein the lock mechanism unlocks and enables only the replacement unit specified by the unit specifying device to be detached from the image forming apparatus after a prescribed time period has elapsed after a notification of replacement was displayed.

14. The image forming apparatus as claimed in claim 1 , wherein the moveable member is a plate that at least partially blocks the opening through which the replacement unit is withdrawn through while the replacement unit is aligned with the opening.

15. A control system connected to at least one image forming apparatus including at least two replaceable image formation units via a communication line, said control system comprising:

an input device configured to input a signal representing occurrence of abnormality in one of an output image and the image forming apparatus recognized by an operator;

an external control apparatus connected to said at least one image forming apparatus;

a unit specifying device, in the external control apparatus, configured to specify a replacement image formation unit to be replaced to resolve the abnormality upon receiving the signal;

a notification device configured to generate notification information identifying the replacement image formation unit that is to be replaced based on the unit specification result; and

a lock mechanism configured to lock and prohibit the replacement image formation unit from being removed from the image forming apparatus, said lock mechanism including a moveable member, wherein the external control apparatus causes the moveable member to be disposed at a position that prohibits the replacement image formation unit from being removed through an opening in the image forming apparatus while the replacement image formation unit is aligned with the opening, and the external control apparatus causes the moveable member to be disposed at another position that allows the replacement image formation unit to be removed through the opening in the image forming apparatus that is aligned with the replacement image formation unit in response to the replacement image formation unit being specified for replacement by the unit specifying device.

16. The control system as claimed in claim 15 , further comprising:

an image formation device configured to form a toner image for image quality determination use on a transfer belt; and

an image reading device configured to read the toner image from the transfer belt for image quality determination use,

wherein said unit specifying device determines image quality of the toner image for image quality determination use based on the reading result and specifies the image formation unit to be replaced in accordance with the quality determination.

17. The control system as claimed in claim 16 , wherein the transfer belt is configured to feed an image carrier through the image forming apparatus, and the toner image for the image quality determination use is not printed onto the image carrier.

18. The control system as claimed in claim 15 , further comprising a plurality of replacement image formation units, wherein the lock mechanism unlocks and enables detachment of only the replacement image formation unit specified by the unit specifying device while other replacement image formation units are locked and prevented from being detached from the image forming apparatus.

19. The control system as claimed in claim 15 , further comprising a plurality of replacement image formation units, wherein the lock mechanism unlocks and enables detachment of all of the plurality of replacement image formation units in response to one of the plurality of replacement image formation units being specified by the unit specifying device.