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:
Oct. 27, 2015
Filed:
Oct. 28, 2009
Hiroyuki Nomaguchi, Nagasaki, JP;
Atsushi Yuge, Nagasaki, JP;
Toshikazu Hayashi, Nagasaki, JP;
MITSUBISHI HEAVY INDUSTRIES, LTD., Tokyo, JP;
Abstract
There is provided a hydraulic pump startup control device in a hydraulic system, which avoids an overloaded state at startup to enable low-temperature, fast startup and maintaining of the temperature with low-cost means in order to improve low-temperature startability. A bypass pathis placed in parallel with a hydraulic main line from a hydraulic tank, and the downstream of the bypass path is made merged with the hydraulic main line. A bypass valvethat opens or closes the bypass path is provided in the bypass path, and a pressure sensor is provided in the inlet of a hydraulic unit in the hydraulic main line. Further, a control deviceto which a pressure detection value in the hydraulic main line is input from the pressure sensor to open the bypass valve based on the pressure detection value upon startup of the hydraulic unit. The control device repeats on-off control to circulate oil in the bypass path while keeping the pump discharge pressure and the flow rate to open the bypass path at startup so that the actuation power of the hydraulic unit will become the maximum in order to rise the hydraulic temperature of the hydraulic main line.