Fujikura Limited

Nof Corporation

Shiro Nakayama

Katsuhiko Takahashi

Satoshi Kunimura

Tohru Takahashi

Takayuki Imai

Shigemi Takahashi

Masao Akutsu

Kazuhiko Goto

Izumi Ishikawa

Kenji Matsui

Toshio Niwa

Toshimitu Hirayama

Mitutaka Tanida

Thoru Nakatsuka

Hiroyuki Miyata

A polyethylene composition which is useful in insulations and joints of extra-high voltage power cables, and in which a cross-linking agent, comprising an organic peroxide subjected to purification processing, and an antioxidant, are blended, wherein the cross-linked composition has a dielectric loss tangent (tan.delta.) of less than or equal to 0.07% at a temperature of 90.degree. C. and under an electric field stress of 20 kV/mm. This polyethylene composition exhibits little dielectric loss, even at high temperatures or high electric field stresses, and is optimally employed in insulations and joints for extra-high voltage power cables of 275 kV or more.

Polyethylene composition for use in insulations and joints of extra-high

The invention relates to a piezoelectric acceleration sensor and to a piezoelectric acceleration device which use a film piezoelectric element. Speicfically, the piezoelectric acceleration sensor and the piezoelectric acceleration sensor device generate relatively large outputs when acceleration occurs along the sensing axis, but produce relatively small outputs from acceleration perpendicular to the sensing axis. In addition, the sensor and the sensor device are relatively unaffected by temperature fluctuations and are highly impact-resistant.

Piezoelectric acceleration sensor and piezoelectric acceleration sensor

A piezo-electric acceleration sensor, including: a piezo-electric polymer membrane element having an element through-hole; a diaphragm having a diaphragm through-hole and attached to the piezo-electric membrane element so that the diaphragm hole is concentric to the element through-hole to form a laminate with a laminate through-hole; and a fixing mechanism, having a sensing hole, for fixing the laminate in a stretched manner, and wherein: the laminate through-hole has about 2.25 to about 80% of the area of the sensing hole; and the diaphragm and the piezo-electric element meet the equation:

Piezo-electric acceleration sensor

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Yachiyo, Japan

Shiro Nakayama