Fujitsu Corporation

Kazuo Shimada

Kazunori Hirose

Nobuyuki Hayashida

Takashi Matsuya

Tokio Muta

Yoshihiro Takamatsuya

Akihiro Komuro

Keisuke Nakamura

Hironori Kanno

Mitsuo Nakamura

Yutaka Yamauchi

Yuichi Sato

Tomokazu Nakashima

Teruaki Yagoshi

Fumihiro Itoh

Katsuei Asano

Shinya Iwaki

Yutaka Hosono

A replaceable unit to be placed in an apparatus, is provided with a relay which includes a latching type switch and outputs a new/used identification signal which indicates whether the replaceable unit is new or used depending on open and closed states of the switch, a detecting part which detects an operating state within the replaceable unit and outputs a state detection signal indicating the operating state, and a single signal line which is used in common for transferring the new/used identification signal and the state detection signal.

Replaceable unit having a function of identifying a new/used state thereof and apparatus operable with the replacement unit

There is provided a device in an accessory apparatus, which is connected with a main apparatus, for protecting a motor driver IC and a logic circuit in the accessory apparatus from the application of a voltage higher than the rated voltage for these circuits, when the connection between the main apparatus and the accessory apparatus (optional apparatus) which receives power from the main apparatus enters an abnormal state. Therefore, even when the power of the main apparatus is ON, the accessory apparatus can be attached to, or removed from, the main apparatus without damaging the circuits. The device comprises an inexpensive element, such as a rectifying diode or a Zener diode.

Accessory apparatus

A transformer and switching regulator that prevents winding's breakdown caused by the leakage magnetic field. A transformer has a core having an air gap, and a winding wound around the core. The turn density of the winding is made least on the air gap. The switching regulator has such a transformer.

Transformer and switching regulator that prevents winding's caused by magnetic field leakage

An image forming apparatus includes a fixing unit having a heat source, a temperature detecting unit for detecting a temperature of the fixing unit, an initial operation necessity detecting unit for determining whether an initial operation should be performed in the image forming apparatus, an initial operation selecting control unit for selecting an initial operation from among a plurality of predetermined initial operations based on the temperature detected by the temperature detecting unit when the initial operation necessity detecting unit detects that the initial operation should be performed, and a control unit for controlling the fixing unit so that the fixing unit performs the initial operation selected by the initial operation selecting control unit. Furthermore, a temperature control apparatus includes a determination unit for determining, based on the detected temperature of the body, whether the temperature of the body should be increased or decreased, a temperature increasing control unit for applying an AC voltage from the AC power supply to the heater so that the temperature of the body is increased when the determination unit determines that the temperature of the body should be increased, and a temperature decreasing control unit for applying to the heater a pulse-shaped AC voltage which is repeatedly turned on and off at a frequency so that the temperature of the body is decreased when the determination unit determined that the temperature of the body should be decreased, the frequency being generally not perceived by people.

Image forming apparatus, control method for controlling the same and

A system capable of suppressing the variation of a conveyance speed of a medium occurring when the rear end of the medium gets away from between a pair of rollers to surely and stably conduct the processing (transfer of a visible image) for the medium in a processing section (a transfer position). Accordingly, this system includes a position detecting section for detecting a position of the medium conveyed, and a control section for, when the position detecting section detects the fact that the rear end of the medium exists at a position immediately before getting away from between resist rollers, executing control so that a medium conveyance speed by the resist rollers becomes equal or substantially equal to a medium conveyance speed by conveyance rollers. This system is applicable to printers including an electrophotographic system.

Conveyance speed control for medium conveyance apparatus

A unit which detects a discharged condition of each of media with a simple and low-cost structure. For this purpose, this unit is designed to output a signal indicative of the passage of the medium, a signal indicative of a full accumulated condition of the media within the medium discharged section and a signal representative of the occurrence of a jam condition of the medium during the passage of the medium. This unit is applicable to printers such as an electrophotographic type printer.

Medium detection unit, medium conveyance apparatus and image formation

Growing community of inventors

Kawasaki, Japan

Kazuo Shimada