An image forming apparatus includes an image carrier that carries an image to be transferred onto a recording medium, a charging member in contact with the image carrier, the charging member that charges the image carrier, an erase unit that erases charge on the image carrier, a current detector that detects a current flowing to the charging member; a forming unit that forms a charged region on a surface of the image carrier, and forms an erased region on the surface of the image carrier using the erase unit, and a state acquisition unit that acquires a deterioration state of the charging member based on (i) a first current flowing in response to applying a voltage from the charging member to the erased region and (ii) a second current flowing in response to applying a voltage from the charging member to the charged region.

An image forming apparatus includes an image carrier that carries an image to be transferred onto a recording medium, a charging member in contact with the image carrier, the charging member that charges the image carrier, an erase unit that erases charge on the image carrier; a current detector that detects a current flowing to the charging member; a forming unit that forms a charged region on a surface of the image carrier, and forms an erased region on the surface of the image carrier using the erase unit, and a state acquisition unit that acquires a deterioration state of the charging member based on (i) a first current flowing in response to applying a voltage from the charging member to the erased region and (ii) a second current flowing in response to applying a voltage from the charging member to the charged region.

An image forming system includes first and second apparatuses. The first image forming apparatus includes a first image forming unit and a first transfer unit. The first image forming unit forms an image of at least one color. The first transfer unit transfers the formed image to a recording medium. The second image forming apparatus includes a second image forming unit and a second transfer unit. The second image forming unit forms an image different in at least a part of colors from the first image forming apparatus. The second transfer unit transfers the formed image to the recording medium on which the image has been formed by the first image forming apparatus. A total resistance of the second transfer unit along a direction in which a transfer current flows is larger than that of the first transfer unit.

An image forming apparatus includes a photosensitive member, a first charging roller, a first cleaning member, a second charging roller, and a second cleaning member. The following relationship is satisfied:
(XL0+L1+L2)(YL3+L4)0
where L0 represents a length of a whole circumference of the first charging roller, L1 represents a length between a first contact area and a first contact position of the first charging roller and the photosensitive member, L3 represents a length of a whole circumference of the second charging roller, L4 represents a length between a second contact area and a second contact position, L2 represents a length between the first contact position and the second contact position, X represents an integer in a range of 0X40, and Y represents an integer in a range of 0Y40.

An image forming apparatus includes a photosensitive member, a first charging roller, a first cleaning member, a second charging roller, and a second cleaning member. The relationship is satisfied

(XL0+L1+L2)(YL3+L4)0 where L0 represents a length of a whole circumference of the first charging roller, L1 represents a length between the first contact area and the first contact position of the first charging roller and the photosensitive member, L3 represents a length of a whole circumference of the second charging roller, L4 represents a length between the second contact area and the second contact position, L2 represents a length between the first contact position and the second contact position, X represents an integer in a range of 0X40, and Y represents an integer in a range of 0Y40.

An image forming apparatus includes: a photoreceptor including a surface layer; a storage that stores a target value of a variation of a film thickness of the surface layer; and a hardware processor that acquires a variation of the film thickness in a first period within which the photoreceptor rotates a predetermined number of times, and sets a margin that is an amount of a portion for allowance with respect to a proper value of a parameter related to control of the photoreceptor, the margin being to be employed after the first period.

In an example, a method of controlling voltage applied to a print blanket within a printing device includes printing a print job. During the printing, a null cycle trigger is received. In response to the trigger, a print blanket bias voltage is reduced from a print bias level to a null bias level.

An image forming apparatus includes a drive device including a first drive transmission passage through which a driving force of a drive source is transmitted to a developer bearer via a first joint and a second drive transmission passage through which the driving force is transmitted to a rotary body via a second joint. The first drive transmission passage and the second drive transmission passage are defined such that one of a first drive transmission ratio to the first joint of the first drive transmission passage and a second drive transmission ratio to the second joint of the second drive transmission passage is an integral multiple of the other of the first drive transmission ratio from the drive source to the first joint of the first drive transmission passage and the second drive transmission ratio from the drive source to the second joint of the second drive transmission passage.

An image forming apparatus includes a drive device including a first drive transmission passage through which a driving force of a drive source is transmitted to a developer bearer via a first joint and a second drive transmission passage through which the driving force is transmitted to a rotary body via a second joint. The first drive transmission passage and the second drive transmission passage are defined such that one of a first drive transmission ratio to the first joint of the first drive transmission passage and a second drive transmission ratio to the second joint of the second drive transmission passage is an integral multiple of the other of the first drive transmission ratio from the drive source to the first joint of the first drive transmission passage and the second drive transmission ratio from the drive source to the second joint of the second drive transmission passage.

An electrophotographic image forming apparatus includes: an image carrier that carries and conveys a toner image; a charging member arranged in contact with or close to the image carrier; a charging power supply that charges the image carrier; an exposurer that forms a latent image on the charged image carrier; a developing member arranged close to the image carrier; a developing power supply that develops the latent image and forms a toner image on the image carrier; a transfer member that transfers the toner image to a medium; and a hardware processor that controls the image forming apparatus, wherein the hardware processor obtains a potential of an exposure part and a non-exposure part, on the image carrier after the toner image has been transferred to the medium, determines a charging bias based on a difference between the obtained potentials, and determines a developing bias based on the determined charging bias.