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, 2004
Filed:
Nov. 13, 2001
Kaoru Kondo, Kokubunji, JP;
Naoki Tsuda, Kokubunji, JP;
Norihiro Takasaki, Kitakyushu, JP;
Yoshifumi Bandou, Kitakyushu, JP;
Masumi Hino, Kitakyushu, JP;
Kenyou Miyata, Tokyo, JP;
Rion Co., Ltd., Tokyo, JP;
Abstract
Apparatus for producing a polishing solution composed of pure water and abrasive grains, the apparatus including a preparation tank to prepare a polishing solution containing abrasive grains at a predetermined concentration, by mixing an abrasive grain-containing slurry and pure water, and a circulation device for circulating the thus prepared polishing solution to keep the solution in a suspended state. The circulation device includes a circulation conduit and a flow-controllable bypass conduit fluidly associated with the circulation conduit providing a constant flow rate and having a light-extinction type particle detector for monitoring the polishing solution so as to detect large abrasive grains having a particle size not less than a predetermined value and measure the number of the large abrasive grains.