Hitachi, Ltd.

Nippon Steel Corporation

Sumitomo Metal Industries, Inc.

Soji Sasaki

Ichiya Sato

Susumu Itoh

Jun Kubota

Junichi Ishii

Kanji Kawakami

Hisao Okada

Masanori Tanabe

Hideo Uzuhashi

Takao Yoneyama

Hisao Yamaguchi

Takashi Kadowaki

Kazuo Fujisawa

Kazuo Miyagawa

Mareo Suto

Shigeru Inose

Koji Kawamura

Shuichi Sato

Yukito Sasaki

A tablet type coordinate input apparatus comprises a flat medium for propagating a longitudinal elastic wave, longitudinal elastic wave detecting elements disposed on part of the end-adjacent side surfaces or of the front surface of the flat medium, a longitudinal elastic wave input member having an end portion terminating in a sharp-pointed end and brought into pressure engagement at that end with any desired position on the surface of the flat medium to radiate the longitudinal elastic wave from that end, an amplifier circuit amplifying electrical signals indicative of the elastic wave detected by the detecting elements, a comparator circuit comparing the signals amplified by the amplifier circuit with a predetermined threshold voltage thereby generating delay pulse signals corresponding to the propagation times of the longitudinal elastic wave, a counter circuit counting the lengths of time elapsed from the time of radiation of the longitudinal elastic wave toward the flat medium as a result of pressure engagement of the input member therewith to the time of generation of the delay pulse signals, and a computing circuit computing the coordinates on the basis of the time signals applied from the counter circuit.

Tablet type coordinate input apparatus using elastic wave

An ultrasonic synthetic aperture testing apparatus comprises transmitting/receiving sections having an ultrasonic wave probe for transmitting and receiving ultrasonic waves at multiple points on the surface of a steel material, an operation section for accumulating the received signals corresponding to the distance between the multiple points and a reproduction point in a desired region of the material under testing, and a display section for displaying an image formed as a result of this accumulation operation. The ultrasonic wave probe is provided with vibrators corresponding to the respective vibration modes so that two kinds of ultrasonic waves in different vibration modes may be transmitted and received. The accumulation section is provided with a mechanism which performs accumulation and arithmetic operation for the two kinds of waves in different modes.

Synthetic aperture ultrasonic testing apparatus with shear and

An electromagnetic-acoustic measuring apparatus is disclosed in which an exciting coil is wound around a body to be inspected in order to generate a magnetic field within the body in the direction parallel to a surface of the body, a transmitting coil is used to generate mechanical strain in the surface of the body by utilizing the magnetic field, a receiving coil detects the mechanical strain at the surface of the body after the mechanical strain has been propagated in the body, the exciting coil is enclosed with a separable core, the transmitting and receiving coils are supported by respective head portions of pole pieces fixed to the core, and the transmitting and receiving coils and pole pieces are water-cooled by means of cooling pipes.

Electromagnetic-acoustic measuring apparatus

First and second magnetic poles are provided, which have end surfaces brought close and in opposition to a material to be examined. These magnetic poles are magnetized by a DC exciter coil such that the magnetic poles have opposite polarities. The first magnetic pole is provided at its end surface with a pair of cumulatively connected transmitting coils, and the second magnetic pole is provided at its end surface with a pair of differentially connected receiving coils. The transmitting coils are connected to a pulser which generates a pulse current, and the receiving coils are connected to a differential amplifier. An electromagnetic ultrasonic wave generated by the transmitting coils are received by the receiving coils, amplified by the differential amplifier, and thereafter supplied to a synchroscope and an automatic detector.

Electromagnetic ultrasonic apparatus

Growing community of inventors

Hitachi, Japan

Soji Sasaki