Hitachi Metals, Ltd.

Tokyo Gas Company Limited

Sankoh Co., Ltd.

Sanko Gas Seiki, Ltd.

Fumitaka Satoh

Tomoyuki Minami

Minoru Fujiyoshi

Tamaki Hamaguchi

Morio Saito

Shinichi Kanomata

Takaaki Inotani

Youichi Uchiumi

Takuji Okiayu

Akihiro Hattori

Fumikazu Ishibe

Takashi Anamizu

Masahiro Mohri

Satoru Araki

Michio Hasegawa

The formation of a resin layer, a metal layer and an insulating resin layer on an outer surface of a corrugated metal pipe for flowing a fluid provides a flexible pipe, whose corrugated metal pipe does not suffer from having apertures even with spark discharge by induced lightning.

Flexible pipe

A pipe joint comprising a pressing nut into which a flexible pipe is inserted, a joint body into which the pressing nut is partially inserted, a resilient means unlocked when pushed by a tip end of the flexible pipe, a sealing member, a retainer engaging the flexible pipe, and an engaging mechanism keeping the pressing nut at a predetermined position in the joint body; the engaging mechanism comprising a stop ring, an annular groove formed on an outer surface of the pressing nut for receiving the stop ring, pluralities of engaging grooves formed on an inner surface of the joint body for receiving the stop ring and communicating with each other; the stop ring engaging both of the annular groove and the first engaging groove before the connection of the flexible pipe is completed; and when the flexible pipe is pulled after completing the connection, the stop ring moving from the first engaging groove to the second engaging groove to draw the pressing nut from the joint body, so that the normal connection of the flexible pipe can be confirmed.

Pipe joint

A pipe joint for connecting a flexible corrugated tube includes a joint body, a sleeve received in an axial through bore in the joint body for holding a free end of the flexible corrugated tube, and a nut threadedly fitted in a threaded portion of the joint body. A shoulder is formed on an inner surface of the through bore, and has an air-tight surface directed toward one end of the through bore. A tapering surface, decreasing in diameter progressively toward the shoulder, is formed on the inner surface of the through bore in adjacent relation to the shoulder. An annular groove of a generally channel-shaped cross-section is formed in the inner surface of the through bore in adjacent relation to the tapering surface. The sleeve has projections extending radially inwardly from one end thereof facing said shoulder, the sleeve having an end surface at the other end thereof. The projections are pivotally movable resiliently relative to the remainder of the sleeve so as to be received in a predetermined one of valleys in the outer peripheral surface of the corrugated tube. The nut has a holding portion for holding outer surfaces of the projections of the sleeve in registry with the annular groove. The nut has a flange surface for abutment against the end surface of the sleeve.

Pipe joint for connection of corrugated tube

Growing community of inventors

Tokyo, Japan

Fumitaka Satoh