Hitachi, Ltd.

Hitachi Automotive Systems, Ltd.

Kentaro Miyajima

Shinya Igarashi

Kisho Ashida

Mitsugu Kusunoki

Shigenobu Komatsu

Masayuki Hio

Junji Onozuka

Hiroyuki Oota

A pressure detecting device is mounted in a measurement target and instrument includes a strain inducer to which pressure of a pressure medium is applied and which generates strain in accordance with the pressure and a strain detecting element that is bonded onto a surface opposite to a pressure receiving surface of the strain inducer, in which the strain detecting element includes one or multiple central strain resistant bridges which are arranged at a central portion of the strain detecting element in a bonded surface direction, and one or multiple outer peripheral strain resistant bridges which are arranged at an outer periphery, and in which, for example, deformation of the strain detecting element caused by an external force when being screw-fixed to the measurement target instrument is obtained through the multiple strain resistant bridges. An error of detection pressure caused by the deformation in a pressure value detected through the central strain resistant bridge is corrected.

Pressure detecting device

A device for measuring mechanical quantity is provided which reduces the influence of a difference in thermal expansion coefficient between an object to be measured and a base plate metal body, and precisely measures a mechanical quantity such as deformation quantity or strain quantity caused in the object to be measured. The device includes a semiconductor strain sensor module for measuring deformation quantity of the object to be measured, and the module includes a metal body, and a semiconductor strain sensor mounted on the metal body to detect strain of the metal body. The object to be measured is made of a material having a thermal expansion coefficient larger than that of the metal body. Further, the metal body mounted with the semiconductor strain sensor has a structure configured to be fixed to the object to be measured.

Device for measuring mechanical quantity

Because of stress occurring due to a change in temperature, and presence of heat distribution on a semiconductor substrate, and a dopant dosage gradient, an offset output occurs to a Wheatstone bridge circuit intended for detection of strain, posing a problem. To solve the problem, diffusion resistors are disposed in the form of a matrix, and bridge resistors R, Reach are formed by selectively connecting diffusion resistors disposed in each odd column, in series with each other, while R, Reach are formed by selectively connecting diffusion resistors disposed in each even column, in series with each other.

Apparatus for measuring a mechanical quantity

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Tokyo, Japan

Kentaro Miyajima