Image forming apparatus

1. An image forming apparatus including:

a photosensitive drum that bears an electrostatic latent image;

a charging roller that charges the photosensitive drum;

a developing roller that develops by toner the electrostatic latent image formed on the photosensitive drum;

a control unit that controls to start rotation of the photosensitive drum and the developing roller in a state of being in contact with each other; and

an estimating unit configured to estimate a value relating to an amount of toner consumption, wherein

the estimating unit estimates the value relating to the amount of toner consumption on the basis of a value relating to an amount of toner that is consumed in a case in which the photosensitive drum and the developing roller are driven in the state of being in contact with each other at a time of startup of the image forming apparatus.

2. The image forming apparatus according to claim 1 , wherein the time of startup of the image forming apparatus is a time of next startup in a case in which previous stopping of an image forming operation is stopping due to interruption of an image forming operation that is being performed.

3. The image forming apparatus according to claim 1 , wherein the time of startup of the image forming apparatus is a time of next startup in a case in which previous stopping of an image forming operation is stopping due to interruption of image forming operation that is being performed, and also in which an elapsed time from the previous stopping is no greater than a threshold value.

4. The image forming apparatus according to claim 1 , wherein the time of startup of the image forming apparatus is a time of rising control execution in which voltage applied to the charging roller and the developing roller is controlled to cause the charging roller, the photosensitive drum, and the developing roller, which are in a standby state, to transition into a state of being capable of image forming.

5. The image forming apparatus according to claim 4 , wherein the estimating unit estimates a value relating to an amount of toner that is consumed at the time of the rising control on the basis of a driving amount of the photosensitive drum in the rising control.

6. The image forming apparatus according to claim 5 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at the time of the rising control, further on the basis of whether or not falling control in which voltage applied to the charging roller and the developing roller is controlled to cause the charging roller and the developing roller, which are in the state of being capable of image forming, to transition into the standby state, has been executed at a time of previous stopping of an image forming operation.

7. The image forming apparatus according to claim 6 , wherein, in the falling control, voltage applied to the charging roller and the developing roller is changed to a target voltage in a stepwise manner.

8. The image forming apparatus according to claim 4 , wherein, in the rising control, voltage applied to the charging roller and the developing roller is changed to a target voltage in a stepwise manner.

9. The image forming apparatus according to claim 1 , wherein the time of startup of the image forming apparatus is a time of falling control execution in which voltage applied to the charging roller and the developing roller is controlled to cause the charging roller, the photosensitive drum, and the developing roller, which are in a state of being capable of image forming, to transition into a standby state.

10. The image forming apparatus according to claim 9 , wherein the estimating unit estimates a value relating to an amount of toner that is consumed at the time of the falling control on the basis of a driving amount of the photosensitive drum in the falling control.

11. The image forming apparatus according to claim 10 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at the time of the falling control, further on the basis of voltage control of the charging roller and the developing roller executed at the time of the falling control.

12. The image forming apparatus according to claim 1 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at the time of startup of the image forming apparatus on the basis of a size of a region on a surface of the photosensitive drum from a position at which the charging roller and the photosensitive drum are in contact to a position at which the developing roller and the photosensitive drum are in contact.

13. The image forming apparatus according to claim 1 , wherein the estimating unit estimates a value relating to a remaining amount of toner at the developing roller on the basis of a value relating to an initial toner amount and a cumulative value of the value relating to the amount of toner consumption.

14. The image forming apparatus according to claim 1 , wherein the estimating unit estimates the value relating to the amount of toner consumption, on the basis of

a value relating to an amount of toner adhering to an image region of the photosensitive drum and an amount of toner adhering to a non-image region, when performing image forming, and

a value relating to an amount of toner that is consumed in a case in which the photosensitive drum and the developing roller are driven in the state of being in contact with each other at the time of startup of the image forming apparatus.

15. The image forming apparatus according to claim 1 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at a time of startup of the image forming apparatus on the basis of a degree of deterioration of the toner.

16. The image forming apparatus according to claim 1 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at a time of startup of the image forming apparatus on the basis of an elapsed time from the previous stopping of the image forming operation.

17. The image forming apparatus according to claim 1 , wherein the estimating unit estimates the value relating to the amount of toner that is consumed at a time of startup of the image forming apparatus on the basis of whether or not the previous stopping of an image forming operation is stopping due to interruption of an image forming operation that is being performed.

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

an environmental sensor that measures environmental conditions of surroundings of the image forming apparatus, wherein

the estimating unit estimates the value relating to the amount of toner that is consumed at a time of startup of the image forming apparatus on the basis of the environmental conditions measured by the environmental sensor.

19. The image forming apparatus according to claim 1 , wherein the developing roller and the photosensitive drum are driven in the state of being in contact with each other at all times.

20. An image forming apparatus including:

a photosensitive drum that bears an electrostatic latent image;

a charging roller that charges the photosensitive drum;

a developing roller that develops by toner the electrostatic latent image formed on the photosensitive drum;

a control unit that controls to start rotation of the photosensitive drum and the developing roller in a state of being in contact with each other; and

an estimating unit configured to estimate a value relating to an amount of toner consumption, wherein

the estimating unit estimates the value relating to the amount of toner consumption, on the basis of a value relating to an amount of toner that is consumed in a case in which the photosensitive drum and the developing roller are driven in the state of being in contact with each other at a time of rotation after an image forming operation onto a recording medium ends.