Canon Kabushiki Kaisha

Minolta Camera Kabushiki Kaisha

Sharp Kabushiki Kaisha Corporation

Comnes Co., Ltd

Minolta Company, Ltd.

Masatoshi Itoh

Hidenori Fukuoka

Takeya Tsukamoto

Tetsuya Yamamoto

Takashi Iida

Yusuke Isomi

Hiroshi Mano

Minoru Hayasaki

Aoji Isono

Kazuhiko Kojima

Nobuyuki Taniguchi

Tokuji Ishida

Hiroshi Ootsuka

Masatake Niwa

Toshiaki Matsumoto

Tatsuro Izumi

Hiroyuki Tsumazawa

Masataka Hamada

Kenji Ishibashi

Atsushi Iwasaki

Takashi Kondo

Toru Ishii

Kentaro Yamashita

Hiroshi Kiten

Daisuke Usami

Seitaro Matsushita

Mamoru Kawanobe

Hiroshi Ueda

Hiroshi Kita

Yasuhiro Shimura

Hiroshi Hagiwara

Akira Kuroda

Hisashi Nagata

Yuki Nishizawa

Tomonori Shida

Shogo Nishiwaki

Hisanori Itoh

Mizuki Ishimoto

Daigo Yoshioka

Yoshio Kuramoto

Atsushi Kuwada

Mitsuhiro Sugita

Nobuo Hasimoto

Yoshimasa Yagi

A motor control apparatus includes: a motor; a transmission mechanism configured to transmit a drive force of the motor to a load of the motor; and a control unit configured to, in case of stopping the motor being rotated at a first speed, decelerate the motor at least at a first deceleration in a first period, in which a rotation speed of the motor is decelerated from the first speed to a second speed lower than the first speed, and decelerate the motor at least at a second deceleration in a second period, in which the motor is decelerated from the second speed until stop, wherein the second deceleration is less than the first deceleration.

Motor control apparatus and image forming apparatus

The motor control apparatus includes: a setting unit configured to set a limit value of coil current flowing through a coil of a motor; a current supply unit configured to supply the motor with the coil current in a range not exceeding the limit value set by the setting unit; a detection unit configured to detect a current value of the coil current; and a comparison unit configured to compare an average value of the current value detected by the detection unit over a predetermined time period with a first threshold value. When the average value has exceeded the first threshold value, the setting unit updates the limit value in a decreasing manner.

Motor control apparatus and image forming apparatus with limiting coil current flowing through motor coil

A motor control apparatus includes: a motor configured to drive a load; and a control unit configured to control the motor. The control unit is configured to, when activating the motor, determine whether a predetermined condition for determining that fluctuation in magnitude of the load occurs is satisfied, activate the motor in a first mode when the predetermined condition is satisfied, and activate the motor in a second mode when the predetermined condition is not satisfied, and the first mode is a mode in which an increase in rotation speed of the motor is gentler than an increase in rotation speed of the motor in the second mode.

Motor control apparatus and image forming apparatus having plurality of activation modes

A motor control apparatus includes: a current supply unit configured to supply a coil current to a plurality of coils of a motor by controlling a voltage to be applied to the plurality of coils, based on a first command value of an excitation current and a second command value of a torque current; and a control unit configured to control the first command value based on a rotation speed of a rotor of the motor, wherein the control unit is further configured to control, when the rotation speed of the rotor is lower than a first threshold value, the first command value to cause the excitation current to be larger than zero, and control the second command value to supply the torque current in accordance with a load of the rotor.

Motor control apparatus configured to control command value of excitation current based on rotation speed of rotor, and image forming apparatus

A motor control apparatus configured to control a motor, includes: a drive circuit of the motor including a semiconductor device and being installed on a different substrate from a substrate of the motor; a load switching unit configured to set a load of the motor in a first state as a first load, and set a load of the motor in a second state as a second load that is smaller than the first load; and a control unit configured to control the drive circuit and the load switching unit, wherein the control unit is configured to control the drive circuit to start rotation of the motor when the load switching unit is in the second state.

An image forming apparatus includes a photosensitive member, a developing roller, first and second motors, a drive-train having a drive switching unit, and a development switching unit. The drive-train transmits a driving force of the first motor to the developing roller. The second motor drives the drive switching unit and the development switching. The drive switching unit switches between a driving force transmission state and a driving force non-transmission state. The development switching unit switches between a developing roller-photosensitive member contact state and a developing roller-photosensitive member separated state, and operates with an operation of the drive switching unit. When the drive switching unit transitions from the non-transmission to the transmission state and a detected magnitude of a current flowing through the first motor has changed, the second motor is stopped before the developing roller is brought into contact with the photosensitive member while driving the first motor.

Image forming apparatus comprising development switching unit and current detection unit

A motor control apparatus includes: a current supply unit configured to supply coil current to a plurality of coils of a motor by controlling, based on a first command value of excitation current and a second command value of torque current, voltage to be applied to the plurality of coils; a first setting unit configured to set the first command value; a second setting unit configured to set the second command value; and a control unit configured to use first control in starting of rotation of a rotor of the motor, and switch control to second control after rotation speed of the rotor becomes greater than predetermined speed. The first setting unit is further configured to set a value greater than 0 as the first command value before the control unit switches control from the first control to the second control.

Motor control apparatus that controls motor, based on command values of excitation current and of torque current, and image forming apparatus

The image forming apparatus includes a fixing device that has a heater, and a required power calculation unit that determines a power Pfsr that is assumed to be required by the heater. Based on a difference between a required power that is determined by the required power calculation unit and a suppliable power, the image forming apparatus selects whether to start printing in a normal mode or to start printing in a power saving mode in which the power that is supplied to the heater is reduced in comparison to the normal mode. The power saving mode includes a plurality of modes, and when a CPU selects the power saving mode, the CPU selects one or a combination of modes from among the plurality of power saving modes based on the aforementioned difference.

Image forming apparatus

An image forming apparatus includes a conveyance unit to convey a sheet toward an image forming position, a torque detection unit to detect a load torque applied to a motor driving the conveyance unit, and a control unit to perform a speed control for changing a rotational speed of the motor such that an interval at which a preceding sheet and a succeeding sheet pass through the image forming position approaches a target interval while the conveyance unit is conveying the succeeding sheet. The control unit executes an interval change processing for changing the target interval in the speed control based on a magnitude of a detected load torque when the conveyance unit is driven by the motor, the control unit controls power input to the motor by transmitting a command signal to a driving circuit of the motor, and the torque detection unit detects the command signal.

Image forming apparatus and sheet conveyance apparatus

An image forming apparatus includes at least one or more rotary members, a motor configured to drive the at least one or more rotary members, a detection unit configured to detect a current value flowing in the motor, and a display unit configured to display information on a state of the at least one or more rotary members. The current value is detected by the detection unit while the at least one or more rotary members are being driven by the motor. When the current value is a first value, information indicating that the at least one or more rotary members are in an abnormal state is not displayed on the display unit. When the current value is a second value larger than the first value, information indicating that the at least one or more rotary members are in the abnormal state is displayed on the display unit.

Image forming apparatus displaying abnormal state of rotary members driven by a motor based on a detected current value

An image forming apparatus includes: a motor; a transfer mechanism configured to transfer driving force of the motor to a load; and a control unit configured to control the motor to rotate a rotor of the motor in a first direction to rotate the load. The transfer mechanism has backlash, and the control unit is further configured to, when control to rotate the rotor in the first direction fails, determine whether or not control to rotate the rotor in the first direction failed due to the motor being faulty, by executing control to rotate the rotor a predetermined amount in a second direction opposite to the first direction.

Image forming apparatus having motor, and motor control apparatus for controlling motor

An image forming apparatus includes a developing roller, a motor, a motor control portion configured to control the motor, a drive switching unit configured to switch between transmission and non-transmission of the rotational driving force of the motor relative to the developing roller, a current detection portion configured to detect a current value of a current to the motor, and an acquisition unit configured to acquire information relating to a rotation amount of the developing roller. The acquisition unit is configured to acquire the information relating to the rotation amount of the developing roller on the basis of a transmission timing at which the rotational driving force is allowed to be transmitted to the developing roller by the drive switching unit and a non-transmission timing at which the rotational driving force is prevented from being transmitting to the developing roller by the drive switching unit.

Image forming apparatus that controls transmission of driving force to a developing roller based on current through a motor

An image forming apparatus includes a toner storing portion, a stirring member that stirs the toner by rotating inside the toner storing portion, a driving unit for rotating the stirring member in a first rotation direction and in an opposite second rotation direction. A control portion controls the motor such that a rotation direction of the stirring member is changed from the first rotation direction to the second rotation direction, and a detection unit that detects a rotation state of the motor, wherein the control portion determines whether to end the rotating operation or not based on the rotation state detected by the detection unit, and wherein the rotation state includes a rotation speed or a rotation amount of the motor.

Image forming apparatus having a two direction rotatable stirring member

A liquid crystal display device includes a liquid crystal display panel including a plurality of pixels, and a control circuit configured to generate a source signal voltage supplied to each pixel. The liquid crystal display panel includes an active matrix substrate including a pixel electrode applied with a source signal voltage and a common electrode applied with a common voltage. The common voltage and the source signal voltage corresponding to each gradation are set such that a source-common center difference at least one of lowest and highest gradation levels is greater than the source-common center difference at least some of the other gradation levels. A degree of symmetry of a gradation level voltage is equal to or lower than 95% at least at one of gradation levels equal to or lower than a 127/255-th gradation level except for the lowest gradation level.

Liquid crystal display device, voltage setting method for liquid crystal display device and method for producing liquid crystal display device

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Mishima, Japan

Masatoshi Itoh