Hitachi, Ltd.

Hitachi Software Engineering Company, Ltd.

Toshihiko Matsuda

Tsutomu Omae

Mitsunari Kano

Yoshiharu Konishi

Morihiko Takashi

Yasuo Morooka

Soshiro Kuzunuki

Yasushi Fukunaga

Hiroshi Shojima

Takashi Ikimi

Hiroshi Nagase

Hitoshi Suzuki

Masaki Miura

Junichi Oizumi

Hiroshi Fujise

Masahiro Kayama

Kaneo Mohri

Makoto Tachikawa

Toshimi Mifune

Junko Mori

Masayuki Tsuchiya

Toshio Takekoshi

Jiro Kino

Kenzo Kamiyama

Ryoso Masaki

Masahiko Watanabe

Kenji Kubo

Nobuyoshi Mutoh

Shuji Katoh

Shigeta Ueda

Haruo Takeda

Yasunori Katayama

Tsutomu Ohmae

Hideki Nihei

Hiroshi Hayashida

Noboru Azusawa

Kazuo Honda

Masahiro Tobise

Kunihiko Onuma

Hiroyuki Hanei

Ichitaro Koai

Mitsuaki Kobayashi

Yoshihiro Kamigane

Takeshi Hanada

Takashi Sukegawa

Yoshiaki Kuno

Hiromitsu Kikuchi

Mistuo Yoshida

Youjirou Miyahara

Hiroshi Nagata

Syozi Yamada

A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series.

Semiconductor power conversion apparatus

Distributed control system and method of configuring the system

A character data input method for an information processing system. Image information on a form which has only a format and on which no data is recorded is read from an input unit for inputting image information. A plurality of input areas in which data is recorded is prescribed by utilizing this image information. Image information on the same form on which data is recorded is thereafter read from the input unit. The format and data are discriminated from image information on the form on which data is recorded based on the recognized character pattern and border pattern of the format and the information prescribing the data input areas to recognize a character pattern in each data input area.

System for inputting character data

A hand-written character recognition apparatus with a personal dictionary preparation function has a character recognition unit for comparing an input hand-written character data with a registered standard dictionary to recognize a most similar character pattern, and a display unit for selecting and displaying a display font corresponding to the recognized character pattern, so that a personal peculiar character or simplified character inputted can be recognized. When a personal dictionary is to be registered, the character to be registered is inputted by hand-writing, the character recognition unit compares the input hand-written character data with the standard dictionary to recognize a similar character pattern, and the recognized character code of the standard dictionary is selected as the character code to be registered. When the personal dictionary is to be prepared, a personal pattern input frame which permits simultaneous input of a plurality of personal hand-written character patterns is provided, and the input personal patterns are allotted to one character code to be registered. When the personal character pattern is to be prepared and registered, similarity between the input personal pattern and the registered dictionary pattern is checked, a stability index indicating a degree of stability of recognition of the personal pattern is calculated based on the similarity, and the stability index is displayed.

Hand-written character recognition apparatus with a personal dictionary

A programmable controller for executing a program having mixed instructions. The programmable controller includes a bit operation memory for storing a mixed instruction inclusive of the mixture of bit operation instructions and word operation instructions in order of execution and a word operation memory for storing the word operation instructions in the mixed instruction in order of execution. A bit operation processor is provided in the programmable controller for outputting a start command for a word operation instruction when a word operation instruction read from the bit operation memory subsequently to the execution of the bit operation instruction has been recognized. The programmable controller also provides a microprocessor for receiving the word operation start command to execute the word operation instruction stored in the word operation memory,

Programmable controller and sequence control method

A magnetic detector for detecting a magnetism present in the vicinity of or close to a magnetic wire circumferentially magnetized therein and an electromagnet for generating an A.C. magnetic field on the basis of the magnitude of a Matteucci-effect voltage developed across the magnetic wire when the electromagnet approaches the magnetic wire. A coordinate input device for detecting proximity between the electromagnet and an array of a plurality of such magnetic wires arranged in X and Y directions when the electromagnet approaches the array. A magnetic image sensor for detecting an intensity distribution of a static magnetic field to be detected and present along a longitudinal direction of the wire on the basis of a detection voltage of the wire when a plurality of such electromagnets arranged along the longitudinal direction of the wire are sequentially excited one after another.

Magnetic detector using Matteucci effect

Coordinate input device using Matteucci effect

A data processing system for inputting data to a form display includes a scanner for inputting an image of a form document to the system, a processor for recognizing character and line patterns from the form document image supplied from the scanner to produce physical structure data of the document and logical structure data related to data input/output fields in the form document depending on the physical structure data so as to automatically produce based on the logical structure data a program to input data to the form display, a display screen for presenting thereon a form display defined by the physical structure data or normalized data obtained by correcting the physical structure data to be adaptive to a cursor pitch, a data input key apparatus, and a printer for producing a printout document based on the form display filled with the data.

Method and system for producing from document image a form display with

An actuator suitable for use in a joint device for driving a robot arm or in a subject follow-up device in a video camera, etc., is designed to have a mobility of a freedom of two degrees or more and is adapted to drive a movable part directly using first piezoelectric motor elements each of which consists of piezoelectric elements having a non-ring-like configuration and an elastic body and second piezoelectric motor elements each of which consists of at most one ring-like piezoelectric element and an elastic member. The actuator exhibits a simplified structure, is small and lightweight, provides a powerful driving power and has a wide range of mobility.

Actuator

A control apparatus for controlling a PWM inverter, the PWM inverter receiving AC power and generating an AC output having a controlled frequency to be supplied to an AC motor, comprises a circuit for generating, on the basis of a given running command, a PWM signal controlling the inverter with a given sampling period, and a circuit for controlling the PWM signal generating circuit, whereby the AC motor generates an electromagnetic tone preselected so as to correspond to desired information when the AC motor is driven by output of the inverter controlled by the PWM signal. The above described desired information may be information representing the running state of the motor or selected music.

Control apparatus for inverter for driving AC motor

A coordinate input apparatus which comprises a display unit having a display layer, and a protecting layer disposed on said display layer and having two-dimensionally arranged light guides for transmitting light from the display layer in the direction substantially perpendicular to the display layer, wherein a user designates a coordinate position on the display layer through the protecting layer.

Coordinate input apparatus

In a speed detecting apparatus for detecting the rotational speed of a rotating body mechanically coupled thereto, an encoder generates one cycle of a sine-wave signal each time its angular position of rotation changes by a predetermined unit amount. A zero-crossing pulse is generated at each zero-crossing point of the sine-wave signal generated from the encoder, and the phase angle of the sine-wave signal is detected on the basis of the zero-crossing point of the sine-wave signal generated from the encoder. In a high speed range, the rotational speed is detected on the basis of the ratio between the number of zero-crossing pulses and the time interval between a first one and a last one of the plural zero-crossing pulses. On the other hand, in a low speed range, the rotational speed is detected on the basis of the combination of the number of the zero-crossing pulses appearing within a predetermined period of time and the phase angle of the sine-wave signal.

Speed detecting apparatus

A speed control apparatus for a motor comprising a motor model formed of a motor current model and a motor speed model connected in cascade, a basic torque instruction signal being applied to the motor model, and first and second control loops comparing output signals from the motor current model and the motor speed model with an instantaneous actual motor current signal and an instantaneous actual motor speed signal respectively and generating first and second correction signal to be added to the basic torque instruction signal to form a corrected torque instruction signal which is applied to a motor current control circuit, whereby a speed oscillation is suppressed even when the motor is driving an oscillatory load.

Speed control apparatus for motor

A PWM inverter includes a plurality of arms connected in parallel with a d.c. power source. Each arm is constituted by an upper arm and a lower arm each having a switching element. A plurality of switching control signals are continuously and alternately applied to one and the other of the two switching elements constituting the same arm respectively. In the PWM inverter, shunt resistors are connected between a minus terminal of the d.c. power source and the lower arms respectively. The PWM inverter further comprises a waveform command generating circuit generating commands representative of current waveforms to be supplied to a load, a carrier wave generating circuit and sample-hold circuits. Each of the sample-hold circuits samples and holds a terminal voltage of the associated shunt resistor in synchronism with the period of the carrier wave generated from the carrier wave generating circuit and at specific timing in a conduction period of the associated switching element.

Load current detecting device for pulse width modulation inverter

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Owariasahi, Japan

Toshihiko Matsuda