Seiko Epson Corporation

Yoshio Nakazawa

Nozomu Inoue

Keiichi Taguchi

Takashi Hama

Hiroshi Nakazato

Kuniaki Tanaka

Tsuyoshi Kowari

Osamu Shinkawa

Masahiko Yoshida

Shinji Morozumi

Toshiyuki Misawa

Kazuhito Fujisawa

Atsushi Akiyama

Yoichi Yamada

Tomohiro Aruga

Daisuke Matsumoto

An ink jet printer is provided with a driving signal generating section which generates a driving signal for driving a piezoelectric element, a residual vibration detecting section, a control IC which includes the residual vibration detecting section, and a connection terminal which connects the piezoelectric element, an input terminal to which the driving signal is supplied and an output terminal from which an output signal of the residual vibration detecting section is supplied, a first external wiring which is connected to the input terminal and through which the driving signal is supplied, and a second external wiring which is connected to the output terminal and through which the output signal of the residual vibration detecting section is supplied. A resistance value per unit length of the second external wiring is larger than a resistance value per unit length of the first external wiring.

Liquid discharging apparatus

An ink jet printer is provided with a piezoelectric element which is provided corresponding to a pressure chamber in order to discharge liquid droplets, a driving signal generating section which generates a driving signal, a residual vibration detecting section which detects changes in an electromotive force of the piezoelectric element in accordance with the residual vibration inside the pressure chamber which occur after the driving signal is applied, a first switch which switches whether or not a driving signal is applied to the piezoelectric element, and a second switch which switches whether or not a change in the electromotive force is supplied to a first high-pass filter, where the second switch and the residual vibration detecting section are connected via a first capacitor of the first high-pass filter.

A developing apparatus includes: a housing which contains toner; a toner supporting roller; and a regulating blade, wherein bias voltage is applied to the regulating blade, the toner includes, an insulating external additive and an electrically-conductive external additive, satisfies any of the following first to third conditions, the first condition: a volume average grain diameter of the electrically-conductive external additive is larger than a volume average grain diameter of the insulating external additive, the second condition: a volume average grain diameter of the electrically-conductive external additive is larger than a volume average grain diameter of the insulating external additive in which coverage in the toner is higher than that of the electrically-conductive external additive, and the third condition: coverage of the electrically-conductive external additive in the toner is higher than coverage of the insulating external additive that is larger in volume average grain diameter than the electrically-conductive external additive.

Developing apparatus, image forming apparatus, image forming method, and toner

A high voltage power supply apparatus according to the present invention is a high voltage power supply apparatus that applies a bias voltage at least to a developing roller of a developing unit, the apparatus comprising: a transformer that increases an AC voltage and includes a main winding and a sub winding on the secondary side thereof; a first capacitor whose first end is connected to a common connection point between the main and sub windings; a second capacitor whose first end is connected to one end of the sub winding which is not the common connection point side; a zener diode whose both ends are connected to the second end of the first capacitor and second end of the second capacitor; and a DC voltage application section that applies a DC voltage to the zener diode, wherein a voltage generated in the second end of the first capacitor is used as a voltage to be applied to the developing roller.

Image forming apparatus

An image-forming apparatus for forming an image by heating a medium, the image-forming apparatus includes a connector connectable to a heating unit that heats the medium; a conmmercial power supply that generates power to be supplied to the heating unit; a switch system, provided between the heating unit and the conmmercial power supply, that switches the supply of the power to the heating unit on or off; and a switch control unit that controls the switch system based on the heating unit type.

Image-forming apparatus

An image forming apparatus which repeats image create/transfer processing while rotating a photosensitive member and a transfer medium in a sub scanning direction and thereafter transferring the toner image onto the transfer medium, for a plurality of toner colors which are different from each other, to thereby lay toner images in respective toner colors over each other on the transfer medium and accordingly form a color image. The apparatus corrects transfer start positions of toner image in at least one or more toner colors out of the plurality of toner colors based on a registration control amount which is necessary to correct relative registration deviations among toner images on the transfer medium.

Image forming apparatus for transferring respective toner colors on a transfer medium

An image forming apparatus and method that repeats image create/transfer processing, in which serial processing of forming a toner image on a photosensitive member while rotating the photosensitive member and a transfer medium in a sub scanning direction and thereafter transferring the toner image onto the transfer medium, for a plurality of toner colors which are different from each other. The apparatus and method lay toner images in the respective toner colors over each other on said transfer medium and accordingly form a color image. Correcting transfer start positions of toner images in at least one or more toner colors out of the plurality of toner colors is based on a registration control amount which is necessary to correct relative registration deviations among toner images on the transfer medium.

Image forming apparatus and method for processing a plurality of toner colors onto a transfer medium

Power transmission members which transmit rotational drive force from a drive source such as a motor, to an intermediate transfer drum is elastically deformed due to a load change which is generated as a cleaning part contacts and moves away from the intermediate transfer drum. Registration control amounts (Ra, Rb and Rc) attributed to the elastic deformation are obtained in advance. Transfer start positions for toner images in at least one or more toner colors out of four toner colors are corrected based on the registration control amounts (Ra, Rb and Rc), whereby registration deviations are suppressed to minimum and a high-quality color image is obtained.

Image forming device having transfer registration control

A toner quantity measuring apparatus in which an input offset voltage is applied to the output side of an irradiation quantity monitoring light receiving element, so that a light emitting element remains turned off unless a light quantity control signal exceeds a predetermined signal level. Prior to irradiation of light upon an intermediate transfer belt and measurement of a toner quantity, a light quantity control signal below the predetermined signal level is supplied to an irradiation quantity adjusting unit and the light emitting element is turned off without fail. A memory stores, as a dark output voltage, an output voltage from a reflection quantity detecting unit upon the turning off. Light reflected from the intermediate transfer belt is split into p-polarized and s-polarized light to detect a toner quantity and colors of the toner. In actual measurement of the toner quantity, with light irradiated upon the intermediate transfer belt, the dark output voltage is subtracted from the output voltage outputted from the reflection quantity detecting unit, whereby an influence of the dark output voltage is eliminated.

Apparatus for measuring quantity of toner, and image forming apparatus comprising measuring apparatus

In an apparatus, first and second processing modes are prepared to determine an optimal development bias. Either one of the first processing mode and the second processing mode is selected as a processing mode in accordance with an operation status of the apparatus. Hence, it is possible to select and execute the most appropriate processing mode in accordance with an operation status to thereby efficiently and highly accurately determine an optimal value of a development bias which is one density controlling factor.

Image forming apparatus and method

Image forming apparatus and method with adjustable image density factor

In the matrix, a positive type liquid crystal of the twisted nematic type is driven by a thin film transistor arranged on a transparent substrate. The polarity of the video signal, originally generated for a cathode ray tube, is inverted within a driving circuit and the inverted negative video signal is used to drive the positive type liquid crystal display. In the range of voltages of the video signal which correspond to the white level, the active matrix panel is driven by stretching the voltage of the video signal such that comparable voltage-contrast characteristics are achieved with the liquid crystal display as with the cathode ray tube. Leakage current of the thin film transistor during off-periods is reduced by setting a gate voltage during the off-period which is within the range of voltage level of the power source.

Growing community of inventors

Nagano-ken, Japan

Yoshio Nakazawa