Ricoh Company, Ltd.

Yoshihisa Kimura

Tetsuya Yano

Kazuhito Kishi

Toshitaka Semma

Naoki Sato

Norio Muraishi

Kazuo Ogawa

Stored DC power is supplied to a load after a return to a normal-power mode or a power-up of an image forming device. An auxiliary power supply does not supply the stored DC power to the load, and a main power supply supplies AC and DC power to the load if it is determined that a predetermined processing is performed upon a starting of the image forming device. The auxiliary power supply supplies the stored DC power to the load, it is determined whether a predetermined time has elapsed, and the main power supply does not supply the AC and DC power to the load if it is determined that the predetermined processing is not performed upon the starting of the image forming device. A decision whether the predetermined processing is performed is based on at least one of a number of sheets, an elapsed time, and an environmental temperature.

Image forming device to supply DC power to a load from both a main power supply device and a capacitor supply device

An image forming apparatus includes a main power unit that outputs a first DC power and an auxiliary power unit that outputs a second DC power to the components of the image forming apparatus. The auxiliary power unit includes a rechargeable capacitor. A measuring unit measures performance of the capacitor and a determining unit determines performance insufficiency of the capacitor based on the measured performance and the system configuration of the image forming apparatus. The performance is, for example, changes in a capacitance of the capacitor with time. When the determining unit determines performance insufficiency of the capacitor, a control unit adjusts, for example, a use range of the capacitor.

Image forming apparatus with a chargeable capacitor

An image forming apparatus having (1) a main power supply unit (PSU), which converts an AC power source into an AC power and a first DC power, provides the AC power to a fusing unit, and provides the first DC power to a plurality of DC-powered units in the image forming apparatus, (2) a supplemental power supply unit, which accumulates the AC power source and provides a second DC power to the plurality of DC-powered units for a predetermined period, and (3) a controller, which increases or decreases the AC power to be provided to the fusing unit and selects the DC power source from the main PSU and the supplemental PSU by detecting that the supplemental PSU can provide the DC power to the plurality of DC-powered units or not. When the supplemental power supply unit can provide DC power to the Plurality of DC-powered units, the controller increases the AC power from the main power supply unit to the fusing unit and shortens the recovery time.

Image forming apparatus with a supplemental power supply unit

A power supply device includes a first power-supply unit to input external power and to output first power supplying a predetermined constant voltage to a load, a second power-supply unit to accumulate charge and to output second power to the load in parallel with the first power being supplied from the first power-supply unit, and a controller to output a control signal to prevent the second power-supply unit from supplying power in case of a current increase due to a dynamic load change, and to cause the first power-supply unit to supply power for the dynamic current increase. The first power-supply unit supplies power having a current value smaller than a predetermined maximum current of the first power-supply unit. The second power-supply unit supplies power for a shortfall current exceeding the predetermined maximum current of the first power-supply unit.

Power supply device capable of supplying large amount of power necessary for entire system operation

A circuit unit connects outputs from a first power supply and a second power supply in parallel, and simultaneously supplies powers from both power supplies to a load. A control unit controls an output current from the first power supply to an upper-limit value or lower, and controls an output current from the second power supply to a value obtained by subtracting the upper-limit value from a current detected by a current detector. An abnormality detector detects an abnormality in simultaneously supplied power, based on a reference current value associated with an operating state of the power supply apparatus and the current detected by the current detector.

Power supply apparatus and image forming apparatus

An image formation apparatus is disclosed. The image formation apparatus includes a manuscript reading unit for reading a manuscript, a main power supply for supplying electric power to an alternating-current load and a direct-current load, and an auxiliary power supply that is capable of storing electric power for supplying electric power to the direct-current load. Power supply to the direct-current load is switched between the main power supply and the auxiliary power supply when reading the manuscript is not being carried out.

Growing community of inventors

Kanagawa, Japan

Yoshihisa Kimura