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:
Nov. 30, 2010
Filed:
Oct. 24, 2006
Kentarou Itoga, Tsukuba, JP;
Tsuyoshi Nakamura, Tsuchiura, JP;
Kazunori Nakamura, Tsuchiura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
In a cooling fan drive system for a travel type working machine, the rotational speed of a cooling fan is controlled to the optimum rotational speed in accordance with temperature increase of the temperature of an engine cooling water, and the engine rotational speed is smoothly increased when the engine rotational speed is increased under travel acceleration. A fourth fan target rotational speed calculatorand a minimum value selectorare provided, and under non-operation, the fan target rotational speed is set to a low rotational speed irrespective of the temperature. When an acceleration pedalis depressed to increase the rotational speed of the engine under travel acceleration, the increase of the drive pressure of a hydraulic motordue to increase of the rotation of the cooling fanis suppressed, and the load on the engineis reduced.