An image forming apparatus includes a mounting portion, a lock mechanism, an image forming unit, a first detection processing unit, a second detection processing unit, a first release processing unit, and a second release processing unit. The first detection processing unit detects a first state where a remaining amount of the developer is less than a predetermined first reference amount. The second detection processing unit detects a second state where the remaining amount of the developer is equal to or more than the first reference amount and less than a predetermined second reference amount. The second reference amount is larger than the first reference amount. The first release processing unit releases the regulation on the attachment/removal of the developer housing portion when the first state is detected. The second release processing unit releases the regulation when unit the second state is detected and a predetermined release condition is met.

An image forming apparatus, including: a converting unit configured to convert image data based on a conversion condition; an image forming unit; a measurement unit; and a controller configured to control the image forming unit to form a plurality of measurement images including a first measurement image and a second measurement image, wherein the controller obtains first output characteristics based on a current measurement result of the first measurement image and a previous measurement result of the second measurement image to generate the conversion condition, and wherein the controller obtains second output characteristics based on a current measurement results of the second measurement image and a previous measurement result of the first measurement image to generate the conversion condition.

A control portion switches first and second modes based on information which influences a toner charging amount. In the first mode, a driving input to the developer bearing member is stopped in response to image formation completion before or at the same time when a trailing end of a charging area reaches the development position, and an application of the development voltage is stopped after the trailing end reaches the development position. In the second mode, The driving input to the developer bearing member is stopped in response to image formation completion before or at the same time when the trailing end reaches the development position, and the application of the development voltage is stopped at a timing after the trailing end reaches the development position and earlier than that in the first mode, or at the same time when the trailing end reaches the development position.

A medium carrying device includes a carrying part that carries a continuous print medium, a detection part that includes a light emitting part and a light receiving part arranged sandwiching a carrying path, and that detects the print medium carried on the carrying path according to a light amount that is received by the light receiving part, and a control part that controls operations of the carrying part and the detection part, wherein the control part sets a first emitted light amount of the emitted light of the light emitting part used in image formation to the print medium by performing a light amount measurement using the light emitting part and the light receiving part in a state where the print medium is carried to a first position, and sets a threshold light amount that is used in detecting a boundary position between the first region and the second region by the detection part through performing another light amount measurement by obtaining a receiving light amount of the light receiving part with the first emitted light amount and by determining the threshold light amount based on the receiving light amount in a state where the print medium is carried from the first position to another second position.

A system and method of printing involves the use of mixed paper sizes in which the orientation of printing media can be selected to avoid a mixture of paper sheet orientations in the output document when auto tray selection has been selected by a user.

Disclosed is an image forming apparatus which includes: a frame with an image forming portion; an operation unit being arranged to be movable with respect to a top surface of the frame; a cable with an electric wire which connects the frame and the operation unit; and an outlet provided on the frame or the operation unit, wherein the cable includes: an elastic member provided along the electric wire from the frame to the operation unit, the elastic member having a width equal to or greater than a diameter of the electric wire; and a protruding portion with elasticity, provided on a side of the elastic member on which the electric wire is arranged such that the protruding portion protrudes from the side of the elastic member, the protruding portion having a height which is equal to or greater than the diameter of the wire.

A drive transmission device (6) includes a first drive train (62) and a second drive train (63). The first drive train (62) includes a first gear (621), a second gear (622), a rotary shaft (623), and one-way clutches (624). The second drive train (63) includes a third gear (631), a fourth gear (632), a rotary shaft (633), and an electromagnetic clutch (634). The third gear (631) engages the first gear (621) and the fourth gear (632) engages the second gear (622). A rotational speed of a pickup roller (12) is switched by switching on/off the electromagnetic clutch (634) to change a transmission path of driving force.

A PWM signal generation unit generates a PWM signal based on a driving voltage so that a midpoint of the longer period out of an H level period and an L level period in each PWM period matches a midpoint of the PWM period. FETs of a full bridge circuit (a driving circuit) are driven according to a PWM signal, and a driving current that corresponds to an A-phase is supplied to a stepping motor. A current detector detects a driving current flowing through an A-phase winding of the motor based on a voltage that is generated across a shunt resistor, at a fixed time point that is in each PWM period and in the H level or L level period that is at the center of the PWM period.

An image forming apparatus includes: an image forming unit configured to form an image on contiguous paper; a job selecting unit configured to select a plurality of jobs to be continuously executed, by user operation; an amount-of-blank setting unit configured to set an amount of blank to be inserted between the plurality of jobs selected by the job selecting unit, by user operation; and a control unit configured to cause the image forming unit to form the image such that a blank of the amount of blank set by the amount-of-blank setting unit is inserted between the plurality of jobs.

Provided is an image-forming apparatus that prevents a drop in processing speed even when a preceding job is interrupted by a simple job (interrupt job). The image-forming apparatus includes a printer unit that prints on paper, a first transporting path that passes by the printer unit, a second transporting path that path branches off from the first transporting path and moves paper that has been turned over from front to back further upstream than the printer unit, a storage unit that stores a condition table indicates conditions for which a preceding job can be interrupted by an interrupt job, and a system-control unit that references the condition table, and when the preceding job can be interrupted, sets a printing order so that printing of the interrupt job is inserted into the printing order of the preceding job.