The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 15, 1983
Filed:
Nov. 25, 1980
Sanshiro Obara, Hitachi, JP;
Ikuro Miyashita, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Presented are a method and apparatus for detecting defect in the water cooling system, e.g. cracking, of a hydrogen-cooled dynamic electric machine. The stator core of the hydrogen-cooled dynamic electric machine is cooled from its inside by cooling water circulated therethrough. When a defect such as crack is caused in the water cooling system, the hydrogen gas leaks into the cooling water. The hydrogen gas is then conveyed by the cooling water to a cooling water supply tank to which the water is recirculated and is accumulated in the upper free space in the water supply tank. Carrier air is forcibly blown into the upper free space of the water supply pipe to prevent the hydrogen concentration from being increased to a dangerous level of explosion threshold. The hydrogen concentration is measured in this state and the defect in the water cooling system is known from the measured concentration of the hydrogen gas.