Ricoh Company, Ltd.

Rioch Company, Limited

Keita Maejima

Yohei Kushida

Yuji Ikeda

Norikazu Okada

Tomoyuki Yamashita

Hayato Fujita

Takuya Murata

Hiroshi Okamura

Takaaki Shirai

Takuma Kasai

Homare Ehara

Masaki Tsugawa

Ryohta Kubokawa

Masahide Yamashita

Natsuko Ishizuka

Satoru Tao

Taku Kumiya

Yasunori Ishigaya

Osamu Kizaki

Shingo Nishizaki

Eiji Enami

Atsuki Iwata

Yushi Miyata

Shiho Shimosaka

Kazuho Satoh

Hiroaki Umezawa

Ryohta Ueba

Yuichi Yomogida

Shuntaro Nakayama

Katsunori Kume

Emiko Kawarasaki

Hironobu Kurihara

Ryota Kubokawa

Koh Tokumaru

Noboru Sugiura

A power supply includes a transformer configured to transform a direct current (DC) voltage and supply an output voltage to a load. The power supply further includes circuitry configured to control the output voltage from the transformer, compare one of an average per unit time of the output voltage and an amplitude value of the output voltage with a threshold in a failure-free state when performing droop control of the output voltage, and determine whether a failure has occurred in at least one of the load and the transformer.

Power supply and image forming apparatus incorporating same

A water content measuring device measures water content of an object to be measured. The water content measuring device includes two plate members that are disposed facing each other, a current generating unit, a measuring unit, and an arithmetic processing unit. The current generating unit generates current supplied between the two plate members. The measuring unit measures electrostatic capacitance generated by the current supplied between the two plate members. The arithmetic processing unit is configured to convert the electrostatic capacitance measured by the measuring unit to water content. Two plate members each have a shape or are disposed such that at least two points on a leading edge of the object enter between the two plate members at different timings in a direction perpendicular to a passing direction in which the object passes through the two plate members.

Water content measuring device, measuring method, and image forming device

A powder-amount detection device includes a first electrode, a second electrode, a third electrode and a voltage detector with the second electrode adjacent to the first electrode on the powder container and have a smaller surface area than a surface area of the first electrode. The third electrode is on a side opposite to the second electrode with the powder container interposed between the third electrode and each of the first electrode and the second electrode. The voltage detector detects voltages of the first electrode and the second electrode by detecting charging and discharging behaviors of the first electrode and the second electrode when a voltage is applied between the third electrode and each of the first electrode and the second electrode for a short time, and detects the amount of powder in the powder container based on the voltages of the first electrode and the second electrode.

Powder-amount detection device and image forming apparatus incorporating same

A thickness detector includes a rotator having different shape marks, disposed at different positions in a rotation direction; an opposing member disposed opposite the rotator; a detector to detect and output a displacement amount of the rotator or the opposing member in a sheet thickness direction; and a controller. The controller is configured to acquire first output values for one rotation from the detector, in a state without sheet; determine, based on a value output from the detector, whether one of the plurality of marks is detected in a state with the sheet held; acquire a predetermined number of second output values after one of the marks is detected; extract, from the first output values, values corresponding to the second output values, based on the value corresponding to the detected mark; and calculate a sheet thickness based on the second output values and the extracted first output values.

Thickness detector and image forming apparatus

A heater controller and heater control method is disclosed. The hater controller includes a detector, a determination circuit, a limiting circuit, a selection circuit, and a driving circuit. The detector detects a temperature of the heating object, which is heated by the heater. The determination circuit determines turn-on ratio for the heater for every control cycle of AC voltage, based on the surface temperature of the heating object and a target temperature of the heating object. The limiting circuit limits the turn-on ratio of current control cycle when the control method of previous control cycle is phase control. The selection circuit selects control pattern to control the heater, based on the turn-on ratio, and the driving circuit applies a heater driving signal to the heater.

Heater control device and image forming apparatus

A remaining powder amount detection device includes: a powder moving portion configured to change a distribution of powder in an inner space of a powder container containing the powder; a drive unit configured to drive the powder moving portion; a change value detector configured to detect a change value indicating a positional change of the powder container; and a remaining powder amount detector configured to detect a remaining amount of the powder contained in the powder container, based on the change value. The drive unit is configured to drive the powder moving portion so as to move the powder to near the change value detector. The remaining powder amount detector is configured to detect the remaining amount based on the change value in a state where the powder is moved to near the change value detector.

Remaining powder amount detection device, image forming device, and remaining powder amount detection method

A powder-amount detection device includes an outer electrode, an inner electrode, and a detector. The outer electrode is disposed outside a powder container to be replaceably installed to an image forming apparatus. The inner electrode is disposed inside a powder supply port of the powder container. The detector is configured to apply an electric field between the outer electrode and the inner electrode to detect a capacitance between the outer electrode and the inner electrode.

An image forming apparatus is provided that forms an image on a sheet material based on a sheet material setting relating to the sheet material. The image forming apparatus includes an accepting unit configured to accept a selection of a sheet material type, a thickness measurement unit configured to measure a thickness of the sheet material, and a setting determination unit configured to determine the sheet material setting that relates to the thickness of the sheet material based on the sheet material type accepted by the accepting unit and the thickness of the sheet material measured by the thickness measurement unit.

Image forming apparatus and setting method

An image forming apparatus includes a fixing device to fix an image on a recording medium by heating the recording medium, multiple heat storing devices to store heat generated at the fixing device, an electric generating element to generate power by converting the heat into power, and a switch to switch connection and disconnection between the electric generating element and at least one of the multiple heat storing devices.

Apparatus, method, and non-transitory recording medium for power generation using heat in image forming apparatus

An image forming apparatus includes a heat-generating component, a power generation device including a thermoelectric element, a heat radiation device, a cooling device, a temperature detector that detects a temperature increase of the heat-generating component, and a controller. The heat radiation device includes a first radiator plate interposed between the heat-generating component and a surface of the thermoelectric element and a second radiator plate attached to another surface of the thermoelectric element. The cooling device cools the first radiator plate. The controller controls operations of the cooling device and the power generation device by operating the cooling device if the detected temperature increase reaches at least a predetermined threshold value, and causing the power generation device to generate power without operating the cooling device to cool the first radiator plate passively if the detected temperature increase falls below the predetermined threshold value.

Image forming apparatus

An image forming apparatus includes a heat generator configured to generate heat in the image forming apparatus; a converter including a capacitor to convert AC power supplied from an external power supply into DC power for a load unit; a thermoelectric transducer configured to convert the generated heat into DC power for the load unit; a detector configured to detect a voltage of the AC power; and a controller configured to cause the converter to continue supplying the DC power to the load unit when a first elapsed time elapsed since the detected voltage drops below a rated voltage is shorter than a first time period shorter than an upper limit of a period of time over which the capacitor is dischargeable, and cause the thermoelectric transducer to supply the DC power to the load unit when the first elapsed time exceeds the first time period.

Image forming apparatus, image forming method, and computer-readable storage medium

A fixing device includes a pressure rotator pressed against a fixing rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A first heater is disposed opposite and heats a first heated span on the fixing rotator spanning in an axial direction thereof. A second heater is disposed opposite and heats a second heated span on the fixing rotator spanning in the axial direction thereof. A temperature sensor unit is disposed opposite an outer circumferential surface of the fixing rotator and includes a first temperature detection element to detect a first temperature of the first heated span on the outer circumferential surface of the fixing rotator and a second temperature detection element to detect a second temperature of the second heated span on the outer circumferential surface of the fixing rotator.

Fixing device and image forming apparatus

A fixing control device includes an image detection unit that determines presence of an image in each of areas obtained by division of an image formation region in which the image is formed, a heater selection unit that selects from heaters of a fixing device heaters at positions corresponding to areas in which the presence of the image is determined, a heating amount computation unit that computes a heating amount of a heating area heated by each of the selected heaters in a fixing region corresponding to the image formation region, a change amount computation unit that computes an amount of change of the heating amount between adjoining ones of the heating areas, and a heating amount correction unit that corrects one of the heating amounts of the adjoining heating areas so that the amount of change after the correction is less than a predetermined threshold.

Fixing control device, fixing control method, and image forming apparatus

A fixing device includes: a heat generating rotating member including a heat generating layer; an exciting coil to inductively heat the heat generating layer; a degaussing coil generating an electrical current in response to a magnetic flux generated by the exciting coil and generating a magnetic flux in an opposite direction; an exciting coil controller configured to control energization of the exciting coil by using PWM signals; a degaussing coil controller determining necessity of switching the degaussing coil and to control energization of the degaussing coil. When the degaussing coil controller switches ON/OFF state of the degaussing coil, the exciting coil controller controls ON time periods of the PWM signals so as to be within a range from minimum to maximum values of the ON time periods of the PWM signals corresponding to the ON/OFF state of the degaussing coil stored in a storage unit.

Fixing device, control method for the same, and image forming apparatus

A reference-data storing unit stores reference data for determining whether to display image data by overwriting display data. A data converting unit converts the image data into display image data. A transparency determining unit determines whether a first pixel value of the display image data obtained through a color conversion by the data converting unit coincides with a second pixel value of the reference data stored in the reference-data storing unit. A data transfer unit that transfers, when it is determined that the first pixel value coincides with the second pixel value, the display image data to a display address space.

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Kanagawa, Japan

Keita Maejima