摘要:
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.
摘要:
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.
摘要:
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 γ-axis current component Iγ 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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.