Image forming apparatus and control method of image forming apparatus

1. An image forming apparatus for the use with a smoother, the image forming apparatus comprising:

a rotatable image carrying member on a surface of which a latent image is formed,

a developing roller structured to develop the latent image on the surface of the image carrying member by providing a developer to the latent image,

an applying roller in contact with the surface of the image carrying member and structured to apply the smoother to the surface of the image carrying member, and

a controller structured to determine whether the image forming apparatus is in a waiting mode wherein the image carrying member is rotated and is ready for a subsequent image forming operation,

wherein the controller is structured to estimate an estimated amount of the smoother on the rotatable image carrying member, rotate the developing roller and stop the applying roller when the estimated amount of the smoother is above a predetermined maximum, and stop the developing roller and rotate the applying roller when the estimated amount of smoother is below a predetermined minimum, when the controller determines that the image forming apparatus is in the waiting mode.

2. An image forming apparatus of claim 1 , wherein the controller is structured to stop the developing roller and the applying roller if the estimated amount of smoother is between the predetermined minimum and the predetermined maximum.

3. An image forming apparatus of claim 1 further comprising a load measurement section to measure load of the rotation of the image carrying member, and

wherein the controller is structured to estimate the smoother amount from the load on the rotatable image carrying member and rotate the developing roller when the load of the rotation of the image carrying member measured by the load measurement section is within a predetermined range and stops the rotation of the developing roller when the load of the rotation of the image carrying member measured by the load measurement section is out of the predetermined range.

4. An image forming apparatus of claim 3 further comprising:

a motor to rotate the image carrying member, and

a current measurement section to measure an electric current on the motor; and

wherein the load measurement section measures load of the rotation of the image carrying member based on the electric current measured by the current measurement section.

5. An image forming apparatus of claim 1 further comprising a time measurement section to measure a length of time that has elapsed since the determination of that the image forming apparatus is in the waiting mode, and

wherein the controller is structured to estimate the smoother amount based on the time elapsed since the start of the standby mode and rotate the developing roller when the length of the time measured by the time measurement section is within a predetermined range and stops the rotation of the developing roller when the length of the time measured by the time measurement section is out of the predetermined range.

6. An image forming apparatus of claim 1 , wherein the controller controls the developing roller to form a patch image on the surface of the image carrying member at a predetermined timing during the rotation of the developing roller in the waiting mode.

7. A method performed in an image forming apparatus, the method comprising:

forming a latent image on a surface of a rotatable image carrying member,

developing the latent image formed on the surface of the image carrying member by providing a developer from a developing roller to the latent image,

applying a smoother to the surface of the image carrying member by an applying roller,

determining whether the image forming apparatus is in a waiting mode wherein the image carrying member is rotated and is ready for a subsequent image forming operation, and

when the controller determines that the image forming apparatus is in the waiting mode, performing the following:

estimating an estimated amount of the smoother on the rotatable image carrying member;

rotating the developing roller and stopping the applying roller when the estimated amount of the smoother is above a predetermined maximum;

stopping the developing roller and rotating the applying roller when the estimated amount of smoother is below a predetermined minimum.

8. A method of claim 7 further comprising stopping the developing roller and the applying roller if the estimated amount of the smoother is between the predetermined minimum and the predetermined maximum.

9. A method of claim 8 further comprising:

measuring load of the rotation of the image carrying member,

estimating the estimated amount of the smoother from the load on the rotatable image carrying member; and

rotating the developing roller when the measured load of the rotation of the image carrying member is within a predetermined range and stopping the rotation of the developing roller when the measured load of the rotation of the image carrying member is out of the predetermined range.

10. A method of claim 9 further comprising measuring an electric current on a motor which rotates the image carrying member, and

wherein the load of the rotation of the image carrying member is measured based on the measured electric current.

11. A method of claim 8 further comprising:

measuring a length of time that has elapsed since the determination of that the image forming apparatus is in the waiting mode, and

estimating the smoother amount based on the on the time elapsed since the start of the standby mode, and

rotating the developing roller when the measured length of the time is within a predetermined range and stopping the rotation of the developing roller when the measured length of the time is out of the predetermined range.

12. A method of claim 8 further comprising controlling the developing roller to form a patch image on the surface of the image carrying member at a predetermined timing during the rotation of the developing roller in the waiting mode.

13. A method of claim 8 further comprising:

measuring load of the rotation of the image carrying member, and

rotating the applying roller when the measured load of the rotation of the image carrying member is within a predetermined range and stopping the rotation of the applying roller when the measured load of the rotation of the image carrying member is out of the predetermined range.

14. A method of claim 13 further comprising measuring an electric current on a motor which rotates the image carrying member, and

wherein the load of the rotation of the image carrying member is measured based on the measured electric current.

15. A method of claim 8 further comprising:

measuring a length of time that has elapsed since the determination of that the image forming apparatus is in the waiting mode, and

rotating the applying roller when the measured length of the time is within a predetermined range and stopping the applying roller when the measured length the time is out of the predetermined range.