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:
Mar. 23, 1999
Filed:
Sep. 09, 1996
Keiji Oda, Hitachinaka, JP;
Hiroshi Hamano, Hitachinaka, JP;
Suetaro Shibukawa, Hitachinaka, JP;
Osamu Koizumi, Ibaraki-machi, JP;
Kiyoshi Hirano, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Car Engineering Co., Ltd., Hitachinaka, JP;
Abstract
A dynamoelectric machine is provided with an arrangement in the form of a plurality of cooling tubes disposed in or adjacent the stator core of the machine and through which a coolant is caused to flow. The coolant tubes extend axially with respect to the rotor of the machine and are spaced around the circumference of the stator. In order to regulate the cooling efficiency and reduce the coolant pressure loss in the coolant tubes, a branching arrangement in combination with a valve arrangement is disposed in at least one of the end brackets of the machine to control the flow of coolant in parallel selectively through different combinations of cooling tubes. The branching arrangement includes a plurality of circumferentially disposed chambers which communicate with respective groups of cooling tubes in parallel, and the valve arrangement allows connection of these chambers selectively in different combinations to a coolant supply and a coolant exhaust. Thereby, the coolant tubes can be connected to form different combinations of parallel passages for carrying coolant to cool the stator of the machine.