An image processing apparatus, having: a setting unit configured to set sheet information on a sheet including a plurality of set values to each of a plurality of sheet feeding trays; and a registration unit configured to, in a case where an instruction to change at least one of the set values included in the sheet information is received, copy the sheet information as tentative sheet information for new sheet information and register at least one of the sheet feeding trays in association with the tentative sheet information.

According to one embodiment, an image forming system includes a photoreceptor system, first and second detection system, a controller, and a determination system. The photoreceptor system having a rotational shaft in a longitudinal direction. The first detection system detects whether there is an abnormality on a surface of the cylindrical photoreceptor system at a first position. The second detection system detects whether there is the abnormality on the surface of the cylindrical photoreceptor system at a second position. The controller causes the second detection system to start detecting of the abnormality at a point in time after a waiting time. The determination system determines damage occurred at a surface position of the surface of the cylindrical photoreceptor system if the second detection system detects the abnormality at the surface position at which the first detection system detected the abnormality.

An image forming apparatus includes a replaceable roller member, an applying unit that applies voltage to the roller member, a current detecting unit that detects a current flowing in the roller member to which the voltage is applied, and a controlling unit. The controlling unit calculates a value of a slope of a current-voltage characteristic of the roller member on the basis of a first current detected when a first voltage is applied to the roller member and a second current that is detected when a second voltage is applied, and determines whether or not the roller member has been replaced on the basis of an amount of change from a value of a first slope calculated at a first timing and a value of a second slope calculated at a second timing later than the first timing.

An image forming apparatus includes a second acquisition processing portion and a third acquisition processing portion. The second acquisition processing portion acquires a first toner image forming condition of a toner image forming portion. The third acquisition processing portion acquires, based on the first toner image forming condition acquired by the second acquisition processing portion, a relational expression that indicates a relationship between a second toner image forming condition of the toner image forming portion and a toner concentration of a specific toner image that is formed by the toner image forming portion. Further, the third acquisition processing portion uses specific expressions that respectively correspond to a plurality of coefficients included in the relational expression to calculate the plurality of coefficients corresponding to the first toner image forming condition acquired by the second acquisition processing portion.

An image forming apparatus includes a charging member configured to charge a photoreceptor, a power supply configured to provide charging power to the charging member, a measurement unit configured to measure a current provided to the charging member, and a controller configured to search for a current saturation point of the charging member using the current value measured by the measurement unit in a state in which fixed direct current (DC) power and varied alternating current (AC) power are supplied to the charging member, and control the power supply to perform a charging operation with only DC power corresponding to the searched current saturation point.

In an image forming apparatus, a first electric pathway connects a charging portion and a power supply unit, a second electric pathway is formed in the photoconductor unit and connects the first electric pathway and the photoconductor. An electrical component is disposed on the second electric pathway and has predetermined electrical property in accordance with the type of the photoconductor unit. A current detection portion is configured to detect current flowing through the second electric pathway when a detection voltage is applied on the first electric pathway. A determination processing portion is configured to determine the type of the photoconductor unit and existence of usage of the photoconductor unit, based on a current value detected by the current detection portion. The blocking portion is configured to block the second electric pathway after determination by the determination processing portion.

An image forming apparatus includes a developing unit and a supply amount increasing unit. The developing unit supplies oil-impregnated particles to an image carrier and develops an electrostatic latent image by a developer on the image carrier which is electrically charged to a polarity that is opposite a polarity of the developer which is electrically charged to a positive polarity or a negative polarity, based on a potential difference between a developing part and the image carrier. The supply amount increasing unit increases an amount of supply of the oil-impregnated particles to the image carrier by adjusting the potential of the image carrier, while a developing operation is not being performed by the developing unit.

Voltages are applied to an image bearing member using at least three application voltage values which are larger than a discharge start voltage value and which have different magnitudes, at least one of the application voltage values having a value at which a direction of a current corresponding to the one of the application voltage values is reverse to those of currents corresponding to the other application voltage values. A relation between the application voltage value and the detection current value in a discharge area is calculated based on at least three application voltage values V.sub.d1, V.sub.d2, V.sub.d3 and at least three detection current values I.sub.d1, I.sub.d2, I.sub.d3 detected by a current detection portion in relation to at least three application voltage values V.sub.d1, V.sub.d2, V.sub.d3 and a voltage value V.sub.0 at which the detection current value is zero is calculated based on the relation in the discharge area.

An image forming apparatus includes: a conveyance section that sequentially conveys a plurality of recording media; a transfer member that transfers an image formed on an image carrier to each of the recording media conveyed by the conveyance section, with a potential difference; a detection section that detects an electrical characteristic value of the transfer member in transferring the image to each of the recording media; and a determination section that determines multi feeding of the recording media, by comparing an electrical characteristic value in transferring the image to each of the recording media with an electrical characteristic value in transferring the image to each of the recording media.

A charge eliminating apparatus configured to remove charges from a sheet on which an image is formed by a printing apparatus, includes a charge eliminating roller pair including a first charge eliminating roller and a second charge eliminating roller configured to form a nip portion together with the first charge eliminating roller, the charge eliminating roller pair being configured to remove the charges from the sheet in a state of contacting the sheet at the nip portion, a first setting unit configured to set a value of a voltage applied to the charge eliminating roller pair, and a second setting unit configured to set whether to apply the voltage to the charge eliminating roller pair, wherein the second setting unit is configured to set whether to apply the voltage to the charge eliminating roller pair without changing the value of the voltage set by the first setting unit.