Method of detecting air gap in gypsum-based building board and method of manufacturing gypsum-based building board

Patent metadata

Field	Value
Publication number	US-9851318-B2
Application number	US-201314434427-A
Country	US
Kind code	B2
Filing date	Jun 17, 2013
Priority date	Oct 18, 2012
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

A method of detecting an air gap in a gypsum-based building board includes cooling a surface of a gypsum-based building board that has generated heat because of a hydration reaction of calcined gypsum by applying a cooling medium to the surface, and detecting a temperature distribution of the surface of the gypsum-based building board after completion of the cooling.

First claim

The invention claimed is:

1. A method of manufacturing a gypsum-based building board, comprising:
forming the gypsum-based building board of a predetermined shape;
cooling a surface of the gypsum-based building board that has generated heat because of a hydration reaction of calcined gypsum by applying a cooling medium to the surface;
detecting a temperature distribution of the surface of the gypsum-based building board after completion of said cooling;
imaging the temperature distribution obtained in said detecting;
automatically detecting an air gap larger than or equal to a predetermined size contained in the gypsum-based building board by performing image processing on an image of the temperature distribution of the surface of the gypsum-based building board obtained in said imaging; and
determining a part of the gypsum-based building board that contains the air gap as being defective, and automatically marking the part and ejecting the part outside a system of a manufacturing process.

2. The method of manufacturing the gypsum-based building board as claimed in claim 1 , further comprising:
issuing an alarm to prompt a change in a manufacturing condition and prompting the change in at least one of manufacturing conditions of a ratio of water to the calcined gypsum, an added amount of a dispersant, a consistency of a gypsum slurry, a rate of manufacturing, and a rotation speed of a vibrator that vibrates the gypsum slurry, when the air gap larger than or equal to the predetermined size is detected.

3. The method of manufacturing the gypsum-based building board as claimed in claim 1 , further comprising:
issuing an alarm to prompt a change in a manufacturing condition, and automatically selecting an optimum manufacturing condition from manufacturing conditions registered with a database and prompting the change to the selected manufacturing condition, when the air gap larger than or equal to the predetermined size is detected.

Assignees

• Yoshino Gypsum Co

Inventors

• Yonezawa Shinji
• Ueno Yasutoshi

Classifications

• B28B17/0072

  Product control or inspection · CPC title

• B28B11/00 Primary

  Apparatus or processes for treating or working the shaped {or preshaped} articles (specially adapted for tubular articles B28B21/92; decoration or surface treatment in general B05, B44; compacting concrete in situ in connection with building E04G21/06; drying F26) · CPC title

• C04B28/14

  containing calcium sulfate cements {(gypsum-paper plates E04C)} · CPC title

• G01N25/72 Primary

  Investigating presence of flaws · CPC title

• G06T7/0008

  checking presence/absence · CPC title