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. 08, 2013
Filed:
May. 26, 2010
Kisaburo Deguchi, Hitachinaka, JP;
Hironori Kaji, Hitachinaka, JP;
Kimihiko Ishii, Hitachinaka, JP;
Daisuke Akieda, Hitachinaka, JP;
Kunihiko Takao, Tsuchiura, JP;
Masaru Yamasaki, Kasumigaura, JP;
Kenji Hiraku, Kasumigaura, JP;
Yoshihiro Nagaoka, Ushiku, JP;
Kisaburo Deguchi, Hitachinaka, JP;
Hironori Kaji, Hitachinaka, JP;
Kimihiko Ishii, Hitachinaka, JP;
Daisuke Akieda, Hitachinaka, JP;
Kunihiko Takao, Tsuchiura, JP;
Masaru Yamasaki, Kasumigaura, JP;
Kenji Hiraku, Kasumigaura, JP;
Yoshihiro Nagaoka, Ushiku, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
It is possible to correctly determine whether a change in the pressure or flow rate is caused by normal opening and closing operations of a check valve and to monitor in real time whether an operation of a check valve is normal or abnormal in a liquid supply device. Light is introduced in the check valve and a change in the quantity of light transmitted through or reflected by the check valve, caused by the opening and closing of the valve is detected, so that the opening and closing operations of the check valve can be directly detected. The check valve is arranged in a pipe in the liquid supply device, and a change in the pressure in the pipe is monitored on the basis of a signal from a pressure sensor and a signal which represents the opening and closing of the check valve.