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:
Apr. 28, 2015
Filed:
Sep. 29, 2010
Toshihisa Toyota, Kobe, JP;
Shuhei Ohtsuka, Kakogawa, JP;
Keita Morikawa, Kobe, JP;
Tomoya Sakuma, Kobe, JP;
Toshihisa Toyota, Kobe, JP;
Shuhei Ohtsuka, Kakogawa, JP;
Keita Morikawa, Kobe, JP;
Tomoya Sakuma, Kobe, JP;
Kawasaki Jukogyo Kabushiki Kaisha, Kobe, JP;
Abstract
The rotational frequency of a variable speed motor is set to a normal rotational frequency setting value (N). A pressure variation range (ΔP) is detected based on a pressure detection value P, of a variable displacement pump, detected by a pressure detector. It is determined whether a determination that the detected pressure variation range (ΔP) is less than or equal to a pressure maintained state detection level (L) has been continuously given for a period indicated by a timer setting value (T). If the determination that the detected pressure variation range (ΔP) is less than or equal to the pressure maintained state detection level (L) has been continuously given for the predetermined period, then it is detected that the current state is a pressure maintained state, and the rotational frequency of the variable speed motor is switched from the normal rotational frequency setting value Nto a pressure maintaining rotational frequency setting value (N(<N)).