Nec Corporation

Fuji Xerox Co., Ltd.

Cocomo Mb Communications, Inc.

Yoshihiro Hagiwara

Kazuo Shima

Hitoshi Minemoto

Junichi Suetsugu

Hitoshi Takemoto

Toru Yakushiji

Tadashi Mizoguchi

Ryosuke Uematsu

Tomoya Saeki

Ryousuke Uematsu

Tadashi Mizocuchi

Kazuhiko Hayashi

Masakazu Okuda

Torahiko Kanda

Fuminori Takizawa

Junichi Suetsucu

A method and apparatus for improving antenna efficiency. A non-grounded conductive object is placed near an antenna. An insulative layer lies between the object and the antenna. The antenna used is preferably a multiband antenna, such as a discone type antenna.

Method and apparatus for improving antenna efficiency

A fluid jetting device is comprised of: a plurality of chambers arranged in a matrix form; nozzles formed in the plural chambers, respectively; a fluid pressure applying portion arranged on at least one planes of the plural chambers; a plurality of fluid pool sub-streams for supplying fluids to the plural chambers; a fluid pool main stream connected to one edges of the plural fluid pool sub-streams; and a fluid supplying portion for supplying a predetermined fluid to the fluid pool main stream. The fluid supplying portion is connected to a portion of the fluid pool main stream in the vicinity of this fluid pool main stream along a longitudinal direction thereof.

Fluid jetting device, fluid jetting head, and fluid jetting apparatus

The present invention provides an oscillating liquid level measuring apparatus includes a liquid level measuring unit having: a floating member floating on a surface of liquid in a tank a variable resistor arranged o the top of the tank for measuring a perpendicular displacement of the floating member a transmitting member extending from the floating member and through the top of the tank for transmitting the perpendicular displacement of the floating member to the variable resistor and holders arranged to sandwich the transmitting members for restricting the movement of the floating member only in the perpendicular direction. A connection portion between the transmitting member and the variable resistor has a predetermined allowance in the displacement direction of the floating member

Oscillating liquid level measuring apparatus

A concentration sensor and a level sensor measure the toner concentration and the volume of a developing solution in a storage tank . A carrier feed pump and a toner feed pump are driven and controlled in real time based upon values detected by the sensors and during the printing operation, in order to feed a concentrated toner or a liquid carrier into the storage tank to maintain the volume and the toner concentration of the developing solution in the storage tank within predetermined ranges. The concentration and the volume are adjusted in real time during the printing operation which therefore needs not be interrupted for adjusting the developing solution. This makes it possible to continue the printing operation for extended periods of time.

Device for adjusting a developing solution for an electrostatic wet-type electrophotographic printer

An ink jet printer has a plurality of ink ejection electrodes for receiving an ejecting voltage to eject an ink droplet, a pulse width generator for specifying the pulse width of each ejecting electrode to obtain a dot diameter of the ink droplet for gray-scale printing. The ejecting voltage Vej for each ejection electrode is divided into a plurality of unit pulses. Each unit pulse is supplied to a corresponding ejection electrode concurrently with unit pulses for other ejection electrodes. A combination of unit pulses for a single ejection electrode forms a single ink droplet having a dot diameter corresponding to the number of unit pulses, thereby achieving accurate gray-scale printing with a reduced circuit scale.

Electrostatic ink jet printer

The present invention provides a toner concentration measuring apparatus capable of precisely measuring the concentration of toner in a developer and having first and second light guiding devices whose end surfaces project into a duct traversed by developer fluid and a light receiving device for receiving light transmitted from the first light guiding device to the second light guiding device.

Toner concentration measuring apparatus

An electrostatic ink jet recording head of a drop-on-demand type has a head body defining an ink chamber for receiving liquid ink containing charged toner particles, a set of electrodes for migrating the liquid ink by electrophoresis and ejecting the liquid ink from an ejecting slit of the ink chamber, and an ink reservoir, disposed above the ink chamber, for circulating the liquid ink by gravity between the ink reservoir and the ink chamber. A flow resistance against the liquid ink in the flow path from the outlet port of the ink chamber to the ink reservoir is smaller than a meniscus force generated by meniscuses formed at the ejecting slit to effectively eject the liquid ink without a pump and without an ink leakage.

Electrostatic ink jet recording head having electrophoretic electrode and gravity ink reservoir

An inkjet device ensuring reliable and stable ink ejection is disclosed. A plurality of ejection electrodes are arranged in a housing having an ink chamber containing ink including toner particles and a gate electrode plate is placed at a predetermined distance from the ejection electrodes. The gate electrode plate has a slit formed such that the ejection electrodes are directed to the slit and an ink drain coupled to the slit for draining ink from the slit.

Electrostatic inkjet head having an ink drain for draining ink from a slit

In a system composed of an uninterruptible power supply UPS) and a computer that is supplied with power from the UPS, the UPS includes a test switch that is turned off by the control of the computer until a test time period has elapsed. The computer includes a test flag memory that holds its data when the UPS does not supply power to the computer. The computer uses the test flag memory to determine whether the UPS is under abnormal conditions.

Test method and system for uninterruptible power supply

An inkjet device having a plurality of ejection electrodes includes a gate electrode plate having a plurality of gate electrodes therein corresponding to the ejection electrodes, respectively. A voltage difference between the ejection electrode and the gate electrode is generated and is changed between a first value and a second value depending on an input signal. The first value is equal to or greater than a threshold value and the second value is smaller than the threshold value. The threshold value is a minimum value which can cause ejection of particulate matter from each ejection electrode.

Inkjet recording apparatus having gate electrodes and print head thereof

An electrostatic ink-jet recording device which provides stable printing by preventing too much charged toner from gathering around an ink discharge aperture even if the charged toner has not been discharged for a long time. If the charged toner is not to be discharged, the potential difference between the electrophoretic electrode and the discharge electrode is so controlled as to suppress electrophoretic movement of the charged toner toward the ink discharging aperture, or the potential difference is made zero. If the charged toner is to be discharged, the voltage applied to the discharge electrode is kept lower than the voltage applied to the electrophoretic electrode for a predetermined period of time before discharging a jet of the charged toner.

Ink-jet recording device for suppressing excess electrophoretic accumulation of charged particles

An electrostatic ink jet printing head comprises printing electrodes formed on the base film of a substrate. The printing electrodes have insulating coating films which coat the printing electrodes, respectively. Each of the printing electrodes has a main electrode portion formed on the base film and a protruding electrode portion which protrudes from the base film. A covering member covers the main electrode portion. The covering member has an internal surface defining, in cooperation with the main electrode portions and the base film, a ink receiving space which receives ink containing toner particles.

Simple electrostatic ink jet printing head having low cost

An inkjet recording apparatus includes an insulating support member having a major surface on which a plurality of ejection electrodes are formed with each of the ejection electrodes protruding from an ejection end of the insulating support member. Each of the ejection electrodes is coated with an insulating material. Further, a cover member is provided to cover the insulating support member to form ink chambers between them and an opening at an ejection end of the cover member. The ejection portion of each ejection electrode protrudes from the ejection end of the cover member through the opening. The ink is supplied from one ink chamber to the ejection electrodes and flows into the other ink chamber through the ejection electrodes.

Injet recording apparatus

An electrostatic ink jet recorder of the type controlling charged toner particles contained in ink by using electrophoresis is disclosed. The recorder achieves a miniature and cost-effective configuration by reducing the number of drivers for driving ejection electrodes and auxiliary electrodes. The same amount of toner particles is ejected from all of ejection electrodes despite a scatter in the ejection electrode and a scatter in the position of the ejection electrode relative to auxiliary electrodes and a counter electrode.

Electrostatic ink jet recorder having ejection electrodes and auxiliary electrodes divided into groups

An inkjet recording apparatus includes a plurality of ejection electrodes and a counter electrode which are controlled at predetermined intervals such that a first voltage pulse is applied to a selected ejection electrode depending on input data and a second voltage pulse is applied to the counter electrode in synchronization with the first voltage pulse. The first and second voltage pulses produce a voltage difference between the selected ejection electrode and the second electrode, wherein the voltage difference is not smaller than a predetermined threshold voltage which is a minimum value which causes ejection of particulate matter from the selected ejection electrode.

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Niigata, Japan

Yoshihiro Hagiwara