Minolta Company, Ltd.

Naoki Matsui

Hideo Hotomi

Kusunoki Higashino

Shoichi Minato

Hisashi Takata

Hiroji Katsuragi

Keishi Sawada

Yasuhiro Sando

Hasashi Takata

A tube-shaped piezoelectric conversion element and a method of fabricating a tube-shaped piezoelectric conversion element are provided. The piezoelectric conversion element is formed either with two electroded piezoelectric sheet elements (two-layer type) rolled up in a tube-shaped member or with a single piezoelectric sheet element (single-layer type) electroded on two opposing surfaces and folded near its center and rolled up in a tube shaped member. A non-electrode surface portion without electrode material disposed thereon is provided on at least one electroded surface of at least one piezoelectric sheet element at an end of the piezoelectric sheet element in a direction intersecting a tube-axis direction. At lease one non-electrode surface portion may also be provided on a piezoelectric sheet element in a region encompassing the fold of single-layer type device. Short circuiting between electrode layers is thereby substantially avoided at ends of the piezoelectric sheet elements or in the fold region.

Piezoelectric conversion element having an electroded surface with a non-electrode surface portion at an end thereof

The present invention relates to an inkjet recording head, which includes an ink cavity and an ink discharge port, a mounting member covering the ink cavity, an oscillating member, and a substrate to support the oscillating member. Various parts of the inkjet recording head are held together with adhesive. In attaching the piezoelectric element to the mounting member, opposing surfaces of the oscillating member and the mounting member are fixed to one another with adhesive. Then, the two members are pressed together, thereby causing excessive adhesive to emerge from between opposing surfaces of the oscillating member and the mounting member. The emerged adhesive is formed into chamfer to provide the oscillating member and the mounting member with areas of attachment that extend beyond the area of attachment that exists between the opposing surfaces.

Inkjet recording head having a driving source attached by a chamfered adhesive layer

An ink-jet recording device (,) comprises a first wall member or partition (,) adjacent to an ink material (,) and a second wall member or partition (,) adjacent to an ink material (,). An elasticity of the first wall member (,) is different from that of the second wall member (,). Arranged adjacent to the first and second wall members (,) are first and second piezoelectric members (,), respectively. Once the piezoelectric members (,) are biased, they deform to force the adjacent ink materials through the wall members (,), ejecting ink droplets of different sizes. This ensures the ink-jet recording head to print a halftone image with a high gradation.

Ink-jet recording device

A piezoelectric element comprising a thin sheet piezoelectric element formed of a piezoelectric ceramic having PZT (PbZrO3.PbTiO3) as a main component with electrodes formed on the surfaces thereof, said thin sheet piezoelectric element being wrapped around a shaft to form a cylinder.

Piezoelectric element, piezoelectric element manufacturing method and actuator using piezoelectric element

An ink-jet recording head for use in an ink-jet printer comprises a plurality of head portions. Each of head portions includes an ink cavity for receiving an ink material, means for pressurizing the ink material in the ink cavity, and a nozzle through which the ink material is ejected. The nozzle has an individual cross section with respect to an axial direction thereof and the cross section of one head portion is different from that of another head portion.

Ink-jet recording head

A recording head comprises a first head member that expels large-diameter ink drops and a second head member that expels small-diameter ink drops. Each of the first head member and the second head member is integrally assembled with a top plate, a partition, a vibration plate and a substrate, which are stacked together one on top of the other. The top plate has multiple groove-shaped concave areas in its surface which faces the partition. Covering these concave areas with the partition forms ink cavities housing ink, ink supply chambers housing resupply ink, and ink inlets connecting the ink cavities to their respective ink supply chambers in first head member and second head member. In addition, nozzles connected to the ink cavities are formed in the side opposite from the ink inlets on the top plate. The cross-sectional areas of the ink inlets of the first head member perpendicular to the direction of ink flow are made smaller or the lengths of said ink inlets are made longer than those of the second head member in the direction of ink flow. In contrast, the configurations and sizes of the nozzles of the first and the second head members are identical, and their impedances are also the same. Therefore, the impedance ratio (ink inlet impedance divided by nozzle impedance) is larger for the first head member than for the second head member, but the values of impedance for both head members are set to be within a range of approximately 0.5 to 6.

Inkjet recording head

An ink-jet recording head (10) includes a first head member (16a) in which a first nozzle (30) is formed, and a second head member (16b) in which a second nozzle (30) is formed. The first and second head members (16a,16b) are made of materials having different repellent characteristics against ink material. Even if the first and second nozzle have the same size, ink droplets ejected from the first and second nozzles (30) have respective diameters. This enables the ink-jet head (10) to eject ink droplets having various sizes to print a highly graded halftone image.

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Sakai, Japan

Naoki Matsui