Ricoh Company, Ltd.

Yuusuke Ishizaki

Takahisa Koike

Ryo Takamatsu

Naoki Sato

Naoki Satoh

Masahide Nakaya

Minoru Takahashi

Koji Kiryu

Hiroto Ohishi

Keiichi Sugai

A load abnormality detection apparatus detects a load abnormality in first and second rotational members acting on each other. An inclination calculation part calculates an inclination of a second control element. A first comparison part compares a first control element with a first threshold value and also with a second threshold value larger than the first threshold value. A second comparison part compares an inclination of change in the second control element with a third threshold value of a negative value and also with a fourth threshold value of a positive value. An abnormality detection part detects a load abnormality in a load applied to the first rotational member and the second rotational member based on results of comparison by the first comparison part and the second comparison part and identifies a cause of the detected load abnormality.

Load abnormality detection apparatus performing accurate judgment of cause of abnormality

A load abnormality detection apparatus includes first and second rotational members that contact each other directly or via a recording medium interposed therebetween, a first motor that drives the first rotational member and is controlled by a first drive current and a second motor that drives the second rotational member and is controlled by a second drive current. The load abnormality detection apparatus further includes a current detection part configured to detect the first and second drive currents, a first judgment part configured to judge whether the first drive current is within a first range, a second judgment part configured to judge whether the second drive current is within a second range and an abnormality detection part configured to detect a load abnormality of the first and/or second rotational members and identify a cause of the load abnormality based on results from the first and second judgment parts.

An image forming apparatus includes a feed unit, a sensor, a control unit, a measuring unit, and a determining unit. The feed unitconveys a sheet. The sensor detects the sheet being conveyed. The control unit controls to change the force acting on the sheet from that is in normal conveyance of the sheet. The measuring unit measures a measurement value related to conveyance speed of the detected sheet with the acting force changed. The determining unit determines whether there is an indication of abnormality in conveyance of the sheet on the basis of the measurement value.

Conveying device, image forming apparatus, and program

A load abnormality detection apparatus detects a load abnormality in at least one of a first rotational member and a second rotational member. An element acquisition part acquires a first control element and a second control element. A first comparison part compares the first control element with a first threshold value and also compares the first control element with a second threshold value larger than the first threshold value. A second comparison part compares the second control element with a third threshold value and also compares the second control element with a fourth threshold value larger than the third threshold value. An abnormality detection part detects a load abnormality in a load applied to at least one of the first and second rotational members based on results of comparison by the first comparison part and the second comparison part and identifies a cause of the detected load abnormality.

A sheet conveying device includes a first rotator, a second rotator, and a third rotator, at least one of which is configured to convey a sheet medium; a first detection unit configured to detect a first control factor for controlling a first motor that rotates the first rotator; a second detection unit configured to detect a second control factor for controlling a second motor that rotates the second rotator; a motor control unit configured to control a rotational speed of a third motor that rotates the third rotator; and a speed control unit configured to request the motor control unit to change the rotational speed of the third motor based on the sum of the first control factor and the second control factor.

Sheet conveying device, image forming apparatus, sheet conveying motor control system, and storage medium

A control device includes a transmission unit including a first gear rotating with a motor shaft and a second gear rotating with a rotating roller which drives a rotated body, a speed detecting unit for detecting the rotational speed of the rotated body or rotating roller, a motor controlling unit for maintaining a constant motor shaft rotational speed based on the rotational speed, a converting unit for converting the rotational speed to a relationship between a frequency contained in a variation of the rotational speed in association with time and a variation value of the rotational speed, and a wear detecting unit for detecting a predictor of wear of cogs in at least one of the first and second gears when the variation value at a specified frequency, determined based on the number of the cogs of the first gear and the motor shaft rotational speed, exceeds a threshold value.

Control device, image forming device, wear detecting method, program, and storage device

A disclosed moving body controlling device includes a first moving body driven by a first motor that is controlled by a first control unit, a second moving body driven by a second motor that is controlled by a second control unit and affecting movement of the first moving body, a memory unit storing a relationship between the second motor rotational speed and an indicating value for driving the first and second motors when the second control unit changes the second motor rotational speed while the first control unit controls a first motor rotational speed to cause a first rotational body surface speed to be a predetermined speed in a mode of setting a second motor target rotational speed, whereby a reference point at which the surface speed starts to exceed the predetermined speed is detected, and based on the reference point the second motor target rotational speed is set.

Moving body controlling device, intermediate transferring device, and image forming apparatus having the same

A plurality of detection target portions are arranged around a rotating shaft of a rotating-body, one of which causes a detector to generate a first detection signal different from a second detection signal generated from the others. A first generating unit generates a reference signal indicating a reference rotational-position of the rotation-driving source or the rotating-body before one rotation from a timing of the first detection signal. A second generating unit reads periodic variation information from a storage unit based on the reference signal, and generates a rotation-velocity correction signal for the rotation-driving source.

Method and device for driving rotating-body, process cartridge, image forming apparatus, and computer program product

A main controller controls a capacitor charger to charge a capacitor as necessary. A sub-controller controls a power saving mode and stops a power supply to the main controller when shifting to the power saving mode. A charge control circuit compares a terminal voltage of the capacitor with a predetermined value by a comparator circuit. If the terminal voltage is lower than the reference value, an AND circuit takes a logical product of an output signal of the comparator circuit and a power saving signal indicating the shift to the power saving mode, and outputs a control signal indicating an instruction to charge the capacitor, to the capacitor charger.

Heating unit, auxiliary power unit, fixing unit, and image forming apparatus

An image forming apparatus includes a fixing unit that thermally fixes a toner image, a power control unit that controls a power supply from an auxiliary power supply to the fixing unit, a job-turnaround-time predicting unit that predicts a job turnaround time for executing an image forming job, a charging-time predicting unit that predicts a charging time for charging the auxiliary power supply, and a control unit that controls a charging operation for the auxiliary power supply and execution of the image forming job based on the job turnaround time predicted and the charging time predicted, such that the job turnaround time for the image forming job is minimized.

Growing community of inventors

Kanagawa, Japan

Yuusuke Ishizaki