Hitachi, Ltd.

Nippon Telegraph and Telephone Public Corporation

Hitachi Device Engineering Co., Ltd.

Hitachi Plant Technologies, Ltd.

Kogyo Gijutsuin

Minoru Hiroshima

Yasuo Fukushima

Naohiko Takahashi

Ryo Suzuki

Osami Matsushita

Shigeru Yoshizawa

Masahiro Yanai

Masatoshi Takeshita

Tatsuo Hamamoto

Atsushi Asano

Nobuo Saito

Shinzo Matsumoto

Hirofumi Ohta

Mitsuho Yoneyama

Yutaka Sugita

Toshio Futami

Yoshifumi Tomita

Hirokazu Aoki

Masaru Takabatake

Kenkichi Suzuki

Ryoji Oritsuki

Hiroaki Yoda

Masuo Kasai

Masaaki Matsuda

Tomohiro Naruse

Minoru Saitoh

Yoshiaki Abe

Tadashi Kaneki

Hironobu Yamada

Hiroshi Suehiro

Hayao Kozai

Tomoaki Tsuboka

Yuichi Hashimoto

Takashi Isoda

Naofumi Sakanashi

Keisuke Mise

Kohzo Hara

Mitsuru Sekino

Hideki Akiniwa

Yoshinori Taniguchi

Mituru Sekino

Teturo Ohashi

Naohumi Sakanashi

Toshikazu Horii

According to the present invention, along the right and left sides of a rotary shaft, flat faces that serve as sealing faces are formed at the circumferential edges, on the suction chamber side, of semicircular division plates, which define suction chambers and a discharge chamber of a volute casing that is divided into two segments. Two disc plates are prepared as pressure test tools, and are positioned on the right and left sides of the rotary shaft so that they contact the flat faces that are formed around the circumferential edges of the division plates near the suction chambers. The two disc plates are then securely connected to a member in the axial direction. In addition, a bolt fastening structure, which is axially tightened by the member that connects the disc plates axially, is provided in at least one axial direction.

Pressure test method of double suction volute pump

In a liquid crystal display device comprising color filters therein, the present invention provides a color-converting material in at least one of the color filters which converts a part of an incident light of the at least one of the color filters into a light in a specific wavalength range together with a filter material passing the light in the specific wavelength range, so as to prevent deterioration of color purity of the light emitted thereby and to improve efficiency of optical utilization therein.

Liquid crystal display device

In a liquid crystal display device comprising a first substrate having switching elements formed for respective pixel electrodes thereon and a second substrate having color filters and a common electrode formed on a main surface thereof, the present invention provides a plurality of columnar spacers formed on both areas of the second substrate inside and outside the common electrode, covers a group of the columnar spacers formed on the common electrode with an alignment film, and arranges another group of the columnar spacers formed around the common electrode at both sides of a sealing material sticking the first substrate and the second substrate to one another. According to the present invention, the group of the columnar spacers fixed to the second substrate with the alignment film firmly secures a gap between the first and second substrates in cooperation with the another group of the columnar spacers arranged so as to compensate for deformation of the sealing material.

Active magnetic bearings supporting a rotor operated at high speeds is controlled by a controller. Tracking filters provided in the controller pick up forward vibration components in synchronism with the rotational speeds from the displacement signals of the rotor, and a mode separating circuit provided in a mode gain controller takes out displacements of the 3rd and 4th modes. Then, a gain controller provided in the mode gain controller determines suitable gains for the separated displacement signals. A mode synthesizing circuit provided in the mode gain controller synthesizes a controlled variable for each of the bearings from the control signals that are processed for the respective modes. By adding the control variable to the respective bearings, the vibration amplitude is suppressed in critical speed zones of high orders, and the rotor is stably operated up to a high-speed range.

High-speed rotor and controller for controlling magnetic bearings used

In a liquid crystal display substrate in which the pixel electrode is applied with a voltage through the drain and source of a thin-film transistor (TFT) that conducts by a voltage applied to the TFT gate electrode, this gate electrode and a busline connected to the gate electrode are formed as a multi-layered structure consisting of a gate layer and at least two layers of a gate insulation film and an amorphous silicon film. The multi-layered structure is formed by etching through a single mask.

Liquid crystal display device having multilayer gate busline composed of

A magnetic bearing is provided with a simulating circuit for estimating a displacement of a rotor on the basis of a force which is exerted on the rotor. An output of the simulating circuit is compared with an actual displacement signal. A delay circuit and a subtracter are provided to subtract a run-out, which was estimated one period before the rotation of the rotor, from the displacement signal. A displacement signal from which the run-out component was eliminated is set to a new displacement signal. A signal which is obtained by adding an estimated run-out of one period before, namely, an output of the delay circuit to the run-out which was estimated by comparing the output of the simulating circuit with the new displacement signal is newly inputted to the delay circuit. Due to this, the run-out component is eliminated from the displacement signal of the magnetic bearing, the load on power amplifiers for driving the electromagnets is reduced, there is a surplus for a saturation which is caused in a high frequency band, the reliability of the control system is improved, and deterioration of positional accuracy due to the run-out is prevented.

Magnetic bearing apparatus and rotating machine having such an apparatus

A controller of magnetic bearing controls the rotor speed with a reduced drive current while suppressing the rotor vibration. The controller implements the ABS control, N-cross control, N-straight control and FF control in proper combination in addition to the basic PID control. A computer in the controller determines the activation of each control in accordance with a predetermined table of control plan in response to the detected rotor speed.

Method and apparatus for controlling a magnetic bearing

A balancing method for balancing a flexible rotor is disclosed. First, the rotor is rotated and vibration of the rotor is measured to determine resonance speeds. Vibration exciting forces of frequencies synchronized with the rotor rotation in two orthogonal directions are imparted to the rotor or rotor support bearings while rotating the rotor at a speed near the respective resonance speeds. The amplitude and the phase of the vibration exciting force which reduces the resonance vibration of the rotor are then determined. A correction weight on the basis of the amplitude and the phase of the vibration exciting force is then determined. Balancing work on the rotor such as grinding of the rotor or addition of a mass to the rotor in accordance with the correction weight is then carried out, followed by a rotor rotation conducted for the purpose of confirming the effect of the balancing work.

Balancing method for flexible rotor and a balancer applicable to the

A magnetic bubble memory has the longitudinal direction of a minor loop, i.e. a row of permalloy patterns, on a magnetic film of a (111) crystal plane aligned with the [110] crystal axis of the magnetic film. By aligning the direction of bubble transfer in the minor loop with the [110] crystal axis, the bias magnetic field margin, .DELTA.H.sub.B, is enabled to increase and the strength of the holding magnetic field, H.sub.DC, is enabled to decrease.

Magnetic bubble memory

A high-density magnetic bubble memory device using magnetic bubbles having a diameter not larger than 2 .mu.m comprises a magnetic layer capable of sustaining the bubbles therein, and a propagation pattern formed in or on a surface of the magnetic layer. In the device, a relation H/d.ltoreq.0.8 is satisfied wherein H is the thickness of the magnetic layer and d the diameter of the bubble. When the propagation pattern is made of a permalloy, h/d (h: bubble height in that case) is not larger than 0.8. When the propagation pattern is formed through ion implantation, h'/d (h': bubble height in that case) is not larger than 0.6.

High-density magnetic bubble memory device

A magnetic bubble detector has a stretcher part for stretching a magnetic bubble while propagating it and a detection part for detecting the magnetic bubble while propagating it. In the magnetic bubble detector, the period of arrangement of bubble propagation elements forming the exit of the stretcher part viewed in a bubble propagation direction is larger than the period of arrangement of bubble propagation elements forming the entrance of the stretcher part viewed in a bubble propagation direction.

Magnetic bubble detector

In a magnetic bubble memory device comprising a number of magnetic bubble propagation bit segments arrayed to form a magnetic bubble propagation path and having each a pattern of a length L in a direction of propagation of magnetic bubbles being less than 3.4 D where D is the average diameter of the magnetic bubbles and is not greater than 2.0.mu., the height H of the pattern of the magnetic bubble propagation bit segments in a direction perpendicular to the propagation direction of magnetic bubbles is set to be in a range of 0.75.times.L.ltorsim.H.ltorsim.1.1.times.L.

Magnetic bubble memory device

A magnetic bubble memory chip comprises minor loops of a folded structure for storing information in the form of magnetic bubble domains, and input and output tracks for transferring the information into and out of the minor loops. The input and output tracks have a pattern repetition period that is four or more times as large as a fundamental period of each of the minor loops.

Magnetic bubble memory chip

A magnetic bubble memory element has a conductor pattern layer including a hair pin shaped conductor loop for generating or dividing magnetic bubbles. A heat sink pattern layer is provided close to the hair pin portion of the conductor loop and may be formed integrally with the loop.

Magnetic bubble memory element with heat sink

A magnetic bubble memory chip is arranged in such a way that the major surface of the chip will not cross perpendicularly with the external bias magnetic field to generate a component of the bias magnetic field which is parallel to the major surface. This component is added to the rotating magnetic field within the chip major surface and the intensity of a resultant rotating magnetic field is shifted to the start/stop direction of this rotating magnetic field. Of the basic elements incorporated in the chip, the basic elements which operate stably in a comparatively intense rotating field is operated in synchronism with the phase of the start/stop direction of the rotating magnetic field in order to ensure stable operation of all the basic elements under the decreased intensity of the external rotating magnetic field.

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Mobara, Japan

Minoru Hiroshima