A paper conveying apparatus and an image forming apparatus are described which can appropriately convey a sheet when the sheet is restarted after forming a loop. The paper conveying apparatus includes a conveying roller pair in the upstream side of a loop roller pair, a stepping motor for rotationally driving the conveying roller pair, and a processor for controlling rotation of the stepping motor by controlling pulse signals and excitation current supplied to the stepping motor. This processor halts rotation of the conveying roller pair by stopping output of the pulse signals when loop formation of the sheet is completed, and switches the excitation current to a lower current value which is lower than a reference current value at which excitation is turned on.

A speed control portion of a motor driving device performs a deceleration control of decelerating a rotation speed of a driving motor based on a first pulse signal for the deceleration control that includes a plurality of pulses whose pulse width corresponds to each commanded speed to the driving motor. A pulse signal output portion generates the first pulse signal and a second pulse signal and outputs the second pulse signal to the speed control portion after outputting the first pulse signal to the speed control portion, wherein the pulse width of the first pulse signal changes by obeying a predetermined rule that corresponds to a deceleration tendency of the rotation speed during the deceleration control, and the second pulse signal does not obey the predetermined rule. When a determination processing portion determines that the second pulse signal is included in an input signal, the deceleration control is ended.

Control closely based on sets of winding data of a fiber bundle is performed even if at least one set of the winding data is skipped. A controller includes a data conversion unit, a reference data setting unit, a transfer unit, and a selector. The data conversion unit converts sets of first winding data generated based on winding conditions into sets of second winding data in which a processing order number is associated with information of a state of a winder. The reference data setting unit sets some of the second winding data as sets of reference data in advance. The transfer unit transfers a selected set of the second winding data to the winder, each time a unit time elapses. The selector is able to set an override value that is used for determining a skip number.

A motor controller (58) according to the present invention includes a pulse width detection portion (595), a speed control portion (591), a pulse width storage portion (596), a same pulse detection portion (597), and a stop processing portion (598). The pulse width detection portion detects the pulse widths of pulses included in the pulse signal. The speed control portion performs: an acceleration control of the drive motor; and a deceleration control of the drive motor. The same pulse detection portion detects, from among the pulses included in the pulse signal inputted during the deceleration control, a pulse in which the pulse width detected by the pulse width detection portion is the same pulse width as the pulse width of an earliest pulse stored in the pulse width storage portion. The stop processing portion stops control of a rotation speed of the drive motor performed by the speed control portion.

A motor controller (58) according to the present invention includes a pulse width detection portion (595), a speed control portion (591), a pulse width storage portion (596), a same pulse detection portion (597), and a stop processing portion (598). The pulse width detection portion detects the pulse widths of pulses included in the pulse signal. The speed control portion performs: an acceleration control of the drive motor; and a deceleration control of the drive motor. The same pulse detection portion detects, from among the pulses included in the pulse signal inputted during the deceleration control, a pulse in which the pulse width detected by the pulse width detection portion is the same pulse width as the pulse width of an earliest pulse stored in the pulse width storage portion. The stop processing portion stops control of a rotation speed of the drive motor performed by the speed control portion.

A speed control portion of a motor driving device performs a deceleration control of decelerating a rotation speed of a driving motor based on a first pulse signal for the deceleration control that includes a plurality of pulses whose pulse width corresponds to each commanded speed to the driving motor. A pulse signal output portion generates the first pulse signal and a second pulse signal and outputs the second pulse signal to the speed control portion after outputting the first pulse signal to the speed control portion, wherein the pulse width of the first pulse signal changes by obeying a predetermined rule that corresponds to a deceleration tendency of the rotation speed during the deceleration control, and the second pulse signal does not obey the predetermined rule. When a determination processing portion determines that the second pulse signal is included in an input signal, the deceleration control is ended.

A post-processing apparatus includes a blade, a transfer mechanism, a sheet folding roller pair, a motor, a drive control device, and a control device. The blade presses into the sheet to form a fold line in the sheet. The transfer mechanism moves the blade toward and away from the sheet. The sheet folding roller pair conveys the sheet with the fold line formed by the blade by pinching the sheet at a nip between the sheet folding roller pair. The motor rotatively drives the sheet folding roller pair. The drive control device controls drive of the motor. The control includes a control circuit. When, through the processor executing a control program, the control device controls the transfer mechanism to withdraw from the nip the blade having been pressed into the sheet and the nip by the transfer mechanism, the control device controls the drive control device to stop the motor.

A medium conveying apparatus includes a conveyance roller to convey a medium, a DC motor to drive the conveyance roller, a processor to rotate the DC motor, an encoder to output a first pulse signal whose cycle varies according to a rotation speed of the DC motor, and an imaging device to acquire an image acquired by imaging a conveyed medium in response to a pulse of a second pulse signal whose cycle is constant. The processor detects a number of pulses of the second pulse signal included in a predetermined cycle of the first pulse signal, and discards images acquired by the imaging device in the same number of pulses as difference between the detected number of pulses and a reference number, in a next cycle of the predetermined cycle of the first pulse signal, when the detected number of pulses exceeds the reference number.