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:
Jan. 29, 1991
Filed:
Mar. 01, 1990
Mitsuaki Watanabe, Inazawa, JP;
Masayoshi Nakane, Nagoya, JP;
NGK Insulators, Ltd., Aichi, JP;
Abstract
A method of inspecting a die having slits of narrow widths and a number of rear apertures communicating with the slits for forming honeycomb structures is able to inspect roughness distributions on inner surfaces of the rear apertures of the die. The method includes steps of irradiating diffused light beams onto an end face of the die on a side of the slits, detecting intensities of light beams arrived at an end face of the die on a side of the rear apertures by irregularly reflecting at inner surfaces of the rear apertures by the use of photosensitive device such as sensitized paper arranged at the end face of the die on the side of the rear apertures, and finally determining roughness distributions of the inner surfaces of the number of rear apertures with the aid of bright and dark portions on the photosensitive device.