From: Jeff Furman (jfurman@ocs.net)
Date: Sat Feb 12 2000 - 17:04:31 PST
Date: Sat, 12 Feb 2000 17:04:31 -0800 (PST) From: Jeff Furman <jfurman@ocs.net> Subject: Re:Guiness Draught Message-ID: <Pine.LNX.4.04.10002121622450.27317-100000@ocs.net>
The plastic ball in the canned Guiness has a small
hole in it. After the can is sealed in the factory, the ball
fills with beer until the pressure is the same inside as outside the ball.
When you open the can, the pressure of the beer surrounding the ball
immediately drops to atmospheric pressure, and the higher pressure inside
the ball forces that beer out through the small hole. The intent is to
make a creamy head in the can, just before you pour it into a glass. The
turbulence caused by the squirting does this. Guiness has a patent that
describes some of the history of this problem; use the IBM patent database
website URL:
http://www.patents.ibm.com
Use the alternate search by patent number for 4832968
I found this patent number printed right on the can's label.
This site is great to bookmark, since lots of things declare their patent
numbers, so you can get some idea how they work. There are some crackpot
patents-- in IBM's "Gallery of Obscure Patents" there was a patent on a
machine that had a striking resemblence to the (a) great pyramid.
Jeff Furman jfurman@ocs.net
This archive was generated by hypermail 2b29 : Thu Oct 19 2000 - 11:10:36 PDT