Image forming cartridge, image forming apparatus and toner cartridge

1. An image forming cartridge, comprising:

a developing unit including:

a developing section configured to use toner for developing; and

a supplying section configured to provide the toner to the developing section;

a toner cartridge containing toner, wherein the toner cartridge includes a stand-by charging unit configured to perform stand-by charge to the toner in the toner cartridge; and

a shutter capable of opening and closing a path from the toner cartridge to the developing unit; wherein

stand-by charging of the toner in the toner cartridge is started in the state where the path is closed with the shutter and the path is opened with the shutter when a predetermined period elapses from the start of the stand-by charging.

2. The image forming cartridge of claim 1 , wherein

the toner cartridge is configured to be detached from and attached to the developing unit, and

the stand-by charging of the toner in the toner cartridge is terminated, when the predetermined period elapses from the start of the stand-by charging.

3. The image forming cartridge of claim 1 , wherein

the toner cartridge comprises a stirring unit configured to stir the toner in the toner cartridge.

4. The image forming cartridge of claim 3 , wherein

the controller opens the path when the stirring unit stirs the toner a predetermined number of times or for a predetermined period after the start of the stand-by charging.

5. The image forming cartridge of claim 1 , wherein

the toner cartridge comprises a toner voltage sensor configured to measure a potential of the toner in the toner cartridge, and

the path is opened when a voltage detected by the voltage measuring unit reaches a predetermined voltage after the start of the stand-by charging.

6. The image forming cartridge of claim 1 , wherein the stand-by charging unit comprises a conductive or semiconductive member configured to stand-by charge the toner.

7. The image forming cartridge of claim 6 , wherein the conductive member includes a metal plate.

8. The image forming cartridge of claim 7 , wherein

the toner is charged by rotation of the stirring unit while voltage is applied to the metal plate.

9. The image forming cartridge of claim 1 , wherein

the developing unit includes a toner level detector configured to detect a residual amount of the toner in the developing unit, and

upon detection of the residual toner amount in the developing unit below a predetermined amount, stand-by charging of the toner in the toner cartridge is activated.

10. The image forming cartridge of claim 9 , wherein the toner level detector includes

a toner level detection bar in the form of a crankshaft;

a gear rotated by a force from outside the cartridge; and

a protruding member connected to the gear, wherein

the residual amount of the toner is detected by determining the drop time of the toner level detection bar as activated by a push from protruding member on the rotated gear.

11. An image forming apparatus, comprising:

an image carrier;

an exposure unit configured to form an electrostatic latent image on the image carrier;

a developing unit that makes the electrostatic latent image visible;

a developer container attachable to the developing unit and configured to supply the developing unit with the developer, the developer container containing the developer;

a replacement detector configured to detect replacement of the developer container;

a stand-by charging unit configured to charge only the developer in the developer container;

a partition provided at a developer path from the developer container to the developing unit and configured to close and open the developer path; and

a controller configured to start stand-by charging of the toner in the toner cartridge in the state where the developer path is closed with the shutter and to open the developer path with partition when a predetermined period elapses from the start of the stand-by charging of the toner in the toner cartridge.

12. The apparatus of claim 11 , further comprising a residual developer indicator configured to detect residual developer in the developing unit, and wherein the detected amount of residual developer changes the duration of stand-by charging upon detection of developer container replacement.

13. The apparatus of claim 12 , wherein the duration of stand-by charging is set only when the detected residual developer is at or below a predetermined reference value.

14. The apparatus of claim 11 , wherein the stand-by charging is performed only when the partition is closed.

15. A toner cartridge comprising:

an identification storing unit configured to store data identifying the toner cartridge;

a stirring unit configured to stir the toner in the toner cartridge, thereby charging the toner;

a conductive or semiconductive member configured to stand-by charge the toner; and

a path connecting the inside and the outside of the toner cartridge, wherein stand-by charging of the toner in the toner cartridge is started in the state where the path is closed and the path is opened when a predetermined period elapses from the start of the stand-by charging.

16. The toner cartridge of claim 15 , wherein the conductive member includes a metal plate.

17. The toner cartridge of claim 15 , wherein the stirring unit comprises:

a gear electrically controlled by a driving source; and

a stirring bar connected to the gear and configured to stir the toner in the toner cartridge by rotation.

18. An image forming apparatus, comprising a developing unit including:

a feed roller configured to charge toner by rotating;

a developing roller configured to supply toner to a photosensitive drum connectable to the developing unit;

a toner restricting member in contact with the developing roller, configured to restrict the amount of toner on the developing roller; and

a shutter configured to open and close a path from a toner cartridge to the developing unit; and

a controller configured to start stand-by charging of toner in the toner cartridge in the state where the path is closed with the shutter and to open the path with the shutter when a predetermined period elapses from the start of the stand-by charging.

19. The apparatus of claim 18 , further comprising:

a charging roller charged to a predetermined voltage;

a photosensitive drum configured to receive toner from the developing member, the surface of the photosensitive drum being charged by the charging roller; and

a cleaning member configured to remove toner on the photosensitive drum.

20. The cartridge of claim 1 , further comprising:

a charging roller charged to a predetermined voltage;

a photosensitive drum configured to receive toner from the developing section, the surface of the photosensitive drum being charged by the charging roller; and

a cleaning member configured to remove toner on the photosensitive drum.

21. The cartridge of claim 1 , further comprising a stand-by charging voltage applying unit configured to apply a voltage to the stand-by charging unit.