Abstract: A sheet conveyance apparatus includes: a speed detection roller that detects a conveyance speed of a sheet by coming into contact with the sheet being conveyed and being driven to rotate; and a hardware processor that performs temperature control to make an ambient temperature of the speed detection roller a predetermined temperature.

Abstract: An image forming system includes: an image forming device that is disposed at a first conveyance path and forms an image on a recording medium that is a continuous sheet or a long sheet; a first conveyor that conveys the recording medium on the first conveyance path in a conveyance direction; an image reader that reads the image formed on the recording medium at a second conveyance path on a downstream side of the first conveyance path in the conveyance direction; a second conveyor that conveys the recording medium on the second conveyance path; and a controller that controls a speed of a drive source of the first conveyor and controls a torque of a drive source of the second conveyor.

Abstract: A posture of a component is to be accurately determined. A posture determination method is to determine, based on an image acquired for a component having a plurality of surfaces, a posture of the component. This posture determination method includes recognizing an outer shape of the component from the image, detecting a feature amount of a surface shape in a determination area being a part of the component based on the outer shape of the component recognized in the recognizing, and determining. In the determining, the posture of the component is determined by comparing a first reference amount indicating a reference feature amount in the determination area of a first surface of the component and a second reference amount indicating a reference feature amount in the determination area of a second surface of the component with the feature amount detected in the detecting.

Abstract: An image forming system includes: an image forming device that is disposed at a first conveyance path and forms an image on a recording medium that is a continuous sheet or a long sheet; a first conveyor that conveys the recording medium on the first conveyance path in a conveyance direction; an image reader that reads the image formed on the recording medium at a second conveyance path on a downstream side of the first conveyance path in the conveyance direction; a second conveyor that conveys the recording medium on the second conveyance path; and a controller that controls a speed of a drive source of the first conveyor and controls a torque of a drive source of the second conveyor.

Abstract: A reading apparatus includes a reader, a conveyor, motors and a hardware processor. The reader reads a surface of a recording medium with an image formed. The conveyor includes rollers disposed along a conveyance path that passes through a reading area of the reader, and conveys the recording medium being laid across the rollers. The motors rotate the rollers. The hardware processor controls operations of the motors such that the rollers located farther downstream in a conveyance direction of the recording medium rotate faster. As to at least one motor of the motors, the hardware processor switches between and performs a first control to adjust a rotational speed and a second control to adjust a torque, depending on an operating state of the motor.

Abstract: A sheet conveyance apparatus includes: a speed detection roller that detects a conveyance speed of a sheet by coming into contact with the sheet being conveyed and being driven to rotate; and a hardware processor that performs temperature control to make an ambient temperature of the speed detection roller a predetermined temperature.

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: 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: 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 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.