Ricoh Company, Ltd.

Hiroyuki Kiguchi

Takuya Murata

Takeo Seki

Natsuko Ishizuka

Shogo Sakamoto

Yuji Tanaka

Haruyuki Suzuki

Takahisa Koike

Jun Shiori

Masami Emoto

Isamu Moriwaki

Ko Tokumaru

Masanobu Nishimiya

An image recording apparatus includes a recording head including a plurality of nozzles from which ink is ejected, a memory, and one or more hardware processors coupled to the recording head and the memory. The one or more hardware processors are configured to: determine, for each of the plurality of nozzles, whether a position of the corresponding nozzle is a position to eject ink; determine whether a successive ejection operation is necessary for a nozzle out of the plurality of nozzles, whose position is determined as the position to eject ink; and cause ink to be successively ejected at the position to eject ink at a predetermined successive ejection frequency from the nozzle that is determined to have the necessity of the successive ejection operation.

Image recording apparatus, image recording method, and recording medium

A current detecting device includes: a drive signal generating unit configured to generate a control signal based on a control voltage value indicating drive force to be applied to a target; a current detecting unit configured to detect a current value output based on the control signal generated by the drive signal generating unit; and a correction unit configured to correct the current value detected by the current detecting unit, based on at least a magnitude of the control voltage value.

Current detecting device, motor controlling system, image forming apparatus, sheet conveying device, robot, and current detecting method

A motor control device includes a detecting unit configured to detect rotation of a motor to be controlled and output a rotation detection value related to the rotation; a drive control unit configured to perform drive control to rotate the motor at a control target value increasing with time based on the rotation detection value; and an abnormality detection unit configured to perform an abnormality detection process for detecting an abnormality in the drive control based on the rotation detection value and a predetermined threshold. The drive control unit performs control to stop rotation of the motor when the abnormality is detected.

Motor control device and motor control method

A motor control device includes a controller configured to output a control signal to a motor driver, the control signal instructing the motor driver to cut off energization of a motor when the control signal and a signal changing depending on driving the motor do not change for a first time period, determine whether the motor is in a position hold state in which control for holding the motor at a position is executed, and change the control signal in a second time period shorter than the first time period when the motor is in the position hold state.

Motor control device, image forming apparatus, motor control method, and computer-readable storage medium

Motor control device, motor control method, and computer-readable storage medium

An electric motor system includes a brushless direct-current motor, a driver circuit, a position sensor, and a control circuit. The motor has an output shaft for transmitting torque. The driver circuit supplies power to the motor according to a control signal input thereto. The position sensor measures an angular, rotational position of the motor shaft. The control circuit controls operation of the motor. The control circuit includes a position sensor terminal, a reference terminal, a differential calculator, a controller, and a gain adjuster. The position sensor terminal receives a feedback signal. The reference terminal receives a reference signal. The differential calculator generates an error signal representing a difference between the measured and targeted rotational positions. The controller generates the control signal based on the error signal through a combination of control actions. The gain adjuster is connected to the controller to adjust a gain of each control action.

Electric motor system and motor control method

A motor control device to execute speed control and position control of motor simultaneously, includes a target position information provider, a target speed information provider, a detected position information detector, a processor to add position feedback information, position feed-forward information, speed feedback information, and speed feed-forward information for output as motor control information, based on the target position information, the setting target speed information, and the detected position speed information, a control voltage generator operatively connected to the processor to generate a control voltage to drive the motor in accordance with the motor control information, and a motor driver operatively connected to the control voltage generator and the motor to control rotation of the motor based on the control voltage.

Motor control device, image forming apparatus including the motor control device, and motor control method

A motor control device supplies a drive control signal to a drive circuit that drives a motor at a constant period using a motor drive signal based on the drive control signal, and shuts off the motor drive signal when a count value counted by a counter that reset the count value if a state of the motor changes exceeds a threshold corresponding to a plurality of driving periods of the motor. The motor control device includes: a control unit that controls a setting unit to set a rotational direction of the motor to a first rotational direction and a second rotational direction reverse to the first rotational direction at the constant period alternately, when a drive mode of the motor is a position holding mode to drive the motor so as to hold a rotational position of the motor.

Motor control device, motor control method, and image forming apparatus

A motor control device includes a motor lock state determining unit configured to determine whether a motor is in a rotation lock state; a position hold state determining unit configured to determine whether the motor is in a position hold state; a lock detection invalidation determining unit configured to invalidate the determination of the lock state when the motor is in the position hold state and when a predetermined condition is satisfied; a position error correction unit configured to correct an error of a target stop position of the motor when the determination of the lock state is invalidated; and a motor control unit configured to change a rotation direction of the motor in a time shorter than a time in which the motor lock state determining unit determines the lock state when the motor is in the position hold state after the error is corrected.

An optical pickup apparatus in which a laser beam reflected from an optical memory medium is separated and incident to a light-receiving element having a plurality of divided light-receiving faces and a focusing error signal is formed on the basis of a difference signal provided by a predetermined combination of light-receiving signals outputted from the respective light-receiving faces of the light-receiving element, comprises a bias signal forming device for forming a bias signal in accordance with a reflectance ratio of the optical memory medium based on a sum of the light-receiving signals outputted from the respective light-receiving faces of the light-receiving element; and a device for superimposing the bias signal on the focusing error signal in an accessing stand-by state with respect to the optical memory medium.

Optical pickup apparatus

Less than half of a laser beam reflected from an optical information storage medium through an objective lens is detected by a detector having two light detecting areas. The sum of output signals from the light detecting areas of the detector is employed to detect when the objective lenas enters a focusing range. The difference between the output signals is employed to detect when the laser beam is focused on the optical information storage medium.

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Kanagawa, Japan

Hiroyuki Kiguchi