Matsushita Electric Industrial Co., Ltd.

Agency of Industrial Science and Technology

Hiroshi Naito

Masayoshi Miura

Kenji Akami

Gen Oda

Tamotsu Kojima

Mutsuaki Murakami

Yasutaka Hiromori

Hidemi Takahashi

Reiji Sano

Minoru Kimura

An ink jet printer having a print head which comprises a front nozzle member having a front channel, a housing secured to the front nozzle member, and a rear nozzle member which defines with the housing a liquid chamber and further defines with the front nozzle member a laminar airflow chamber. The rear nozzle member has a forwardly projecting nozzle and a rear channel extending from the liquid chamber through the projecting nozzle in axial alignment with the front channel to form a meniscus at the front end. The airflow chamber is connected to an air supply for directing air to a point between the front and rear channels so that it creates a sharp pressure gradient along a path therebetween. A dead air region is created in a location adjacent the exit end of the rear channel to cause the meniscus to take a dome-like shape which is stabilized against vibrations and transients. An electric field gradient is established between the front channel and the meniscus to cause the latter to extend toward the front channel and expelled through the front channel.

Ink jet printer

An ink jet printer having a print head which comprises a front nozzle member having a front channel, a housing secured to the front nozzle member, and a rear nozzle member which defines with the housing a liquid chamber and further defines with the front nozzle member a laminar airflow chamber. The rear nozzle member has a forwardly projecting nozzle and a rear channel extending from the liquid chamber through the projecting nozzle in axial alignment with the front channel to form a meniscus at the front end. An electric field gradient is established between the front channel and the meniscus to cause the latter to extend toward the front channel and expelled through the front channel. A portion of the front nozzle member is rendered liquid-repellant to prevent the field distribution from being seriously disturbed by an ink layer formed on it by stray liquid particles.

A thermally insulating casing accommodates an infrared ray sensing element. The casing has a window which conducts infrared ray to the sensing element. The window is covered with heat absorption gas. An infrared ray emitting element may be accommodated within the casing. The casing may have a second window which passes infrared ray generated by the emitting element. The second window may be covered with the heat absorption gas.

Infrared ray sensing device

In an ink jet printer, a print head comprises a front nozzle member having a front channel, a housing secured to the front nozzle member, and a rear nozzle member which defines with the housing a liquid chamber and further defines with the front nozzle member a laminar airflow chamber. The rear nozzle member has a forwardly projecting nozzle and a rear channel extending from the liquid chamber through the projecting nozzle in axial alignment with the front channel to form a meniscus at the front end. The airflow chamber is connected to an air supply for directing air to a point between the front and rear channels so that it creates a sharp pressure gradient along a path therebetween. A dead air region is created in a location adjacent the exit end of the rear channel to cause the meniscus to take a dome-like shape which is stabilized against vibrations and transients. An electric field gradient is established between the front channel and the meniscus to cause the latter to extend toward the front channel and expelled through the front channel. A portion of the front nozzle member is rendered liquid-repellant to prevent the field distribution from being seriously disturbed by an ink layer formed on it by stray liquid particles.

Ink jet printer and method for fabricating a nozzle member

An ink jet printing head comprises a laminar airflow chamber having a front channel through a combined stream of air and ink droplets is discharged toward a writing surface, and a rear channel provided through an insulative plate and axially aligned with the front channel connected to a source of liquid. The chamber is further provided with an air intake connected to a pressurized air supply source for directing an airstream to a point between the front and rear channels so that the airstream makes a sharp turn at the entry into the front channel with the result that a sharp pressure gradient is produced in the liquid discharge path. A first electrode is provided around said front channel and second electrode is provided on a rear side wall of said insulative plate around said rear channel. Electric field is established between said first and second electrodes thereby causing the liquid's meniscus at the exit end of the rear channel to extend toward the front channel by the combined effects of the potential and pressure gradients and to be torn apart into a droplet which is carried by the airstream discharged through the front channel.

Ink jet printing head utilizing pressure and potential gradients

An ink jet recording sheet comprising a paper support applied on at least one surface thereof or internally with a composition which comprises an aqueous dispersion of polyvinylpyrrolidone, vinylpyrrolidone-vinyl acetate copolymer or a mixture thereof serving as a binder or sizing agent and a white filler. The white filler is contained in a weight ratio, to the binder, of 10:1 to 0.2:1 when the composition is applied on the surface of the paper support. When the composition is internally incorporated in the recording sheet, it comprises 10 to 60 parts by weight of the filler and 2 to 20 parts by weight of the binder per 100 parts by weight of pulp.

Ink jet recording sheet

In a nonimpact printer a device is provided for feeding a constant pressure fluid to a nonimpact printing head reciprocally movable to scan across a recording sheet. The feeding device is formed with a pair of identical first and second chambers connected respectively to first and second sections of a conduit through which the fluid is supplied from a source to the device. Fluid communication is established between the first and second chambers by a connecting channel which is smaller in cross section than the cross section of the first and second chambers and is connected to the printing head through a narrow passageway.

Device for feeding constant pressure fluid

An ink jet printing head comprising a nozzle plate having a plurality of nozzles successively arranged in a row. An airflow chamber is in communication with the nozzles for discharging air and ink therethrough to a writing surface and connected to a source of pressurized air for causing an airstream to make sharp turns at the entry into the nozzles creating a plurality of sharp pressure gradients. A liquid chamber is located behind the airflow chamber and connected to a source of ink. A meniscus forming member is located between the air and liquid chambers for causing the ink to form at least one meniscus by surface tension over an area extending parallel with the row of nozzles. Under the influence of the pressure gradients the meniscus of the ink is contoured into a plurality of surfaces convexed toward the nozzles. Electric fields are selectively established between the nozzles and the convexed surfaces for causing the ink to extend toward the corresponding nozzles to be torn apart into droplets which are discharged through the nozzles to the writing surface.

Ink jet printing head having a plurality of nozzles

An ink jet printing head comprises laminar airflow chamber having a front channel through which a combined stream of air and ink droplets is discharged toward a writing surface, and a rear channel axially aligned with the front channel connected to a source of liquid. The chamber is further provided with an air intake connected to a pressurized air supply source for directing an airstream to a point between the front and rear channels so that the airstream makes a sharp turn at the entry into the front channel with the result that a sharp pressure gradient is produced in the liquid discharge path. An electrode is provided for establishing a field between the front channel and the liquid's meniscus at the exit end of the rear channel to cause the latter to extend toward the front channel by combined effects of the potential and pressure gradients and to be torn apart into a droplet which is carried by the airstream discharged through the front channel.

Growing community of inventors

Machida, Japan

Hiroshi Naito