Home . . . About Us . . . . Site Index
Secure Order Form




The book Silent Salesman provides us with a very useful guide for estimating the age of a machine. He provides us with the year that patents were issued. For example, the patent number of 1,743,000 was issued in 1930. Therefore, if your machine bares that number, you know that your machine was made after 1930.

The patent date, however, can be very misleading because sometimes a patent on a specific part of the machine was patented many years before the machine was manufactured. For example, the patent on a 1 cent coin slide is 1933, but that is the patent date for the coin slide, not the machine. To check a patent number, you can search for a patent from the Patent Office web site.

Go to: Patent Search Page

or by writing to:

Patent and Trademark Office
U.S. Dept. of Commerce
P. O. Box 5
Washington, D.C. 20231

Enclose a check for each patent you want (Double check latest fees). It takes about four weeks to receive a reply.

There are two kinds of patents: Regular patents which cover "how a machine works" and design patents which cover "how a machine looks". The first regular patent number was issued in 1836, the first design patent number was issued in 1843. Here are a few patent numbers and the years in which they were issued.

				REGULAR		        DESIGN

		1850		    7,000		    300
		1875		  160,000		  8,000
		1900		  650,000		 33,000
		1910		  950,000		 41,000
		1920		1,350,000		 55,000
		1930		1,750,000		 81,000
		1940		2,200,000		120,000
		1950		2,500,000		160,000


Copyright: 2009 Ken Durham, GameRoomAntiques





Go back to
Sales Lists, Wanted Lists and Trade Lists menu.
Go back to GameRoomAntiques

For more information on: Who We Are & Our Privacy Policy

Ken Durham
3000 Galloway Ridge, C-306
Pittsboro NC 27312
For Orders Only: 202-213-1585 (10am - 9pm East Coast Time)
All others, please email: durham@GameRoomAntiques.com