Abstract: In a motor control device in one embodiment, an initial position estimation unit estimates an initial position of a magnetic pole of a rotor of a motor in an inductive sensing scheme. At each of energization angles, the initial position estimation unit multiplies a ?-axis current component I? corresponding to a peak value of a current flowing through a stator winding by each of a cosine value and a sine value of a correction angle obtained by correcting each of the energization angles. The initial position estimation unit estimates the initial position of the magnetic pole of the rotor based on a ratio between an integrated value of a multiplication result about the cosine value and an integrated value of a multiplication result about the sine value.

Abstract: In a motor control device that controls a sensorless-type motor, a controller estimates an initial magnetic pole position of a rotor of a motor by an inductive sensing scheme while sequentially setting a plurality of energization angles. At each of the set energization angles, the controller converts peak values of currents flowing through a plurality of phases of a stator winding into a first current component having an electrical angle that is equal to a corresponding one of the set energization angles and a second current component that is different in electrical angle by 90 degrees from the first current component, to correct the first current component based on the second current component. The controller estimates the initial magnetic pole position of the rotor based on the corrected first current component that is obtained at each of the set energization angles.

Abstract: A motor controller that controls a motor in which a rotor using a permanent magnet is rotated by a rotating magnetic field due to a current flowing through a winding: performs hold control that continuously causes a fixed excitation current to flow through the winding to cause a fixed magnetic field for suppressing rotation of the rotor to be generated in a suspension period in which the motor is stopped; performs hold enhancement control that enhances the fixed magnetic field with input of a timing signal defined in advance as a trigger, in the suspension period; and starts rotational excitation control that generates the rotating magnetic field when a rotation start timing arrives.

Abstract: A control circuit of a motor control device estimates an initial magnetic pole position of a rotor using an inductive sensing scheme. When estimating the initial magnetic pole position, a drive circuit applies a voltage to a stator winding at each of L electrical angles (L?5) while changing the L electrical angles. An absolute value of an electrical angle difference of the voltage applied to the stator winding between an i-th time (2?i?L) and an i?1st time is 180?360/L degrees or more and 180+360/L degrees or less. An absolute value of an electrical angle difference of the voltage applied to the stator winding between a 1st time for initial position estimation and a last time before starting initial position estimation is 180?360/L degrees or more and 180+360/L degrees or less.

Abstract: A motor controller that controls a motor in which a rotor using a permanent magnet is rotated by a rotating magnetic field due to a current flowing through a winding: performs hold control that continuously causes a fixed excitation current to flow through the winding to cause a fixed magnetic field for suppressing rotation of the rotor to be generated in a suspension period in which the motor is stopped; performs hold enhancement control that enhances the fixed magnetic field with input of a timing signal defined in advance as a trigger, in the suspension period; and starts rotational excitation control that generates the rotating magnetic field when a rotation start timing arrives.

Abstract: A motor controller for controlling a brushless DC motor is provided. The motor controller includes a vector control unit configured to perform a sensorless vector control on the brushless DC motor in accordance with an input command value; a storage portion configured to store time-series control target values so that an amount of rotation angle of the brushless DC motor transitions in a same manner as an expected pattern; and a command portion configured to input, to the vector control unit, the control target values serially as the command value.

Abstract: An image forming apparatus that transfers an image from an image carrier onto a sheet passing between the image carrier rotating and a transfer member includes a fixing unit configured to thermally fix the image on the sheet while nipping and conveying the sheet with a pair of fixing members after the transfer, at least one of the fixing members rotating; a measuring unit configured to measure surface movement speed of the sheet in a non-contact manner while the sheet is being conveyed by the fixing members; and a control unit configured to control rotation speed of the fixing members in accordance with a result of the measurement, to adjust speed of conveyance of the sheet to a target speed determined beforehand for peripheral speed of the image carrier, the control being performed while the sheet being conveyed is in contact with the transfer member and the fixing members.

Abstract: A reading apparatus that reads a sheet includes: a first light emitting diode (LED) configured to emit light with a specific wavelength; a light emitting element including a second LED configured to emit light with the specific wavelength and a phosphor configured to be excited by the light emitted from the second LED; a line sensor configured to generate a reference signal according to a quantity of received light emitted from the first LED and reflected off the sheet, and also generate an image signal according to a quantity of received light emitted from the light emitting element and reflected off the sheet; and a controller configured to generate an image representing the sheet from a differential result obtained by removing a component corresponding to the reference signal from the image signal.

Abstract: A controller for a permanent magnet synchronous motor having a rotor using a permanent magnet is provided. The rotor rotates by a rotating magnetic field caused by a current flowing through an armature. The controller starts a deceleration control of reducing a rotational speed of the rotor when a stop command is inputted in a state where the rotor rotates at a predetermined rotational speed; and performs a fixed excitation control when the rotational speed is reduced to a set speed. The fixed excitation control includes setting a current for causing a magnetic field vector for stopping the rotor at a target position in accordance with an amount of rotation of the rotor since the deceleration control has started and passing the current through the armature.

Abstract: A controller for a permanent magnet synchronous motor having a rotor using a permanent magnet includes a drive portion configured to apply a current to a winding to drive the rotor; an estimating portion configured to estimate a position of magnetic pole of the rotor; and a control unit configured to control the drive portion to cause the rotating magnetic field based on the estimated position of magnetic pole and to control the drive portion to stop the rotor in response to a stop command inputted. The control unit controls, as the control to stop the rotor, the drive portion to determine a current for generating a magnetic field vector which draws the position of magnetic pole of the rotor to a stop position to stop the rotor based on a latest estimated position of magnetic pole, and to keep applying the current determined to the winding.

Abstract: A reading apparatus that reads a sheet includes: a first light emitting diode (LED) configured to emit light with a specific wavelength; a light emitting element including a second LED configured to emit light with the specific wavelength and a phosphor configured to be excited by the light emitted from the second LED; a line sensor configured to generate a reference signal according to a quantity of received light emitted from the first LED and reflected off the sheet, and also generate an image signal according to a quantity of received light emitted from the light emitting element and reflected off the sheet; and a controller configured to generate an image representing the sheet from a differential result obtained by removing a component corresponding to the reference signal from the image signal.

Abstract: An image display and photographing system includes a display device configured to display a target image on a surface; a photographing device configured to photograph the surface; a first detector configured to detect that an object moves away from a space between the surface and the photographing device; a second detector configured to detect that, after the first detector detects that the object moves away from the space, the surface is touched at a predetermined position; a third detector configured to detect that, after the second detector detects that the surface is touched at the predetermined position, the object moves away from the space; and a photographing control portion configured to control, after the third detector detects that the object moves away from the space, the photographing device to photograph the surface.

Abstract: An image forming apparatus that transfers an image from an image carrier onto a sheet passing between the image carrier rotating and a transfer member includes a fixing unit configured to thermally fix the image on the sheet while nipping and conveying the sheet with a pair of fixing members after the transfer, at least one of the fixing members rotating; a measuring unit configured to measure surface movement speed of the sheet in a non-contact manner while the sheet is being conveyed by the fixing members; and a control unit configured to control rotation speed of the fixing members in accordance with a result of the measurement, to adjust speed of conveyance of the sheet to a target speed determined beforehand for peripheral speed of the image carrier, the control being performed while the sheet being conveyed is in contact with the transfer member and the fixing members.

Abstract: A photographing system includes a photographing device configured to photograph a surface; a detector configured to detect a change in a position of an object in a space between the surface and the photographing device; and an obtaining portion configured to obtain an image of an area of the surface by the photographing device when the detector detects the change, the area being not viewed by the photographing device before the change due to interruption of the object and being viewed by the photographing device after the change.

Abstract: Provided is an image forming apparatus including: a heater heating a fixing member; an acquisition unit acquiring, when an image for one page includes a coded identifier image, information on a range of formation of the coded identifier image on a recording sheet in a sheet-passing direction; a target temperature switching unit switching a target temperature at which temperature of the fixing member is to be maintained at least between a first fixing temperature and a second fixing temperature higher than the first fixing temperature; a controller controlling the heater so that the temperature of the fixing member is maintained at the target temperature, wherein the target temperature switching unit switches the target temperature at a timing such that the temperature of the fixing member is equal to the second fixing temperature while a toner image in the range of formation of the coded identifier image is being fixed.

Abstract: An image display and photographing system includes a display device configured to display a target image on a surface; a photographing device configured to photograph the surface; a first detector configured to detect that an object moves away from a space between the surface and the photographing device; a second detector configured to detect that, after the first detector detects that the object moves away from the space, the surface is touched at a predetermined position; a third detector configured to detect that, after the second detector detects that the surface is touched at the predetermined position, the object moves away from the space; and a photographing control portion configured to control, after the third detector detects that the object moves away from the space, the photographing device to photograph the surface.

Abstract: Provided is an image forming apparatus including: a heater heating a fixing member; an acquisition unit acquiring, when an image for one page includes a coded identifier image, information on a range of formation of the coded identifier image on a recording sheet in a sheet-passing direction; a target temperature switching unit switching a target temperature at which temperature of the fixing member is to be maintained at least between a first fixing temperature and a second fixing temperature higher than the first fixing temperature; a controller controlling the heater so that the temperature of the fixing member is maintained at the target temperature, wherein the target temperature switching unit switches the target temperature at a timing such that the temperature of the fixing member is equal to the second fixing temperature while a toner image in the range of formation of the coded identifier image is being fixed.

Abstract: A fixing device includes an excitation coil, a fixing member heated by electromagnetic induction by the excitation coil, a magnetic shunt alloy member, a Curie temperature of which is higher than a target fixing temperature, a determiner that determines whether the temperature of a non-sheet passing region of the fixing member is about to reach the Curie temperature, and a power controller that controls power supplied to the excitation coil. Until the determiner determines that the Curie temperature is about to be reached, the power controller performs feedback control to provide power to the excitation coil. When the determiner determines that the Curie temperature is about to be reached, the power controller switches to fixed power control so that a difference between power supplied when the Curie temperature is about to be reached and power supplied after reaching the Curie temperature falls within an allowable range.

Abstract: Attachment of a USB memory is sensed and whether the USB memory can be recognized or not is determined based on data information output from the USB memory. When the USB memory cannot be recognized, an emulation transition screen is displayed. Thereafter, when an instruction to start transition to an emulation mode is given, an emulation mode transition instruction signal and an IP address of an MFP on a network are output. Receiving the input of the emulation mode transition instruction signal, an emulation mode start-up/end unit starts up the emulation mode.

Abstract: Attachment of a USB memory is sensed and whether the USB memory can be recognized or not is determined based on data information output from the USB memory. When the USB memory cannot be recognized, an emulation transition screen is displayed. Thereafter, when an instruction to start transition to an emulation mode is given, an emulation mode transition instruction signal and an IP address of an MFP on a network are output. Receiving the input of the emulation mode transition instruction signal, an emulation mode start-up/end unit starts up the emulation mode.