Patent Page

Potter's Valve Actuation

| September 2005

  • 09-05-016-Pat-2.jpg

  • 09-05-016-Patent-3.jpg

  • 09-05-016-Pat-1.jpg

  • 09-05-016-Pat-2.jpg
  • 09-05-016-Patent-3.jpg
  • 09-05-016-Pat-1.jpg

Gas Engine Patents of Note 

Little is known of the Valda W. Potter engine and very few, if any, exist today. However, Potter's valve actuation system, the focus of his patent, appears to have been a well-engineered design.

In his patent letter, Potter stated: "The object of the invention is, primarily, to provide a novel form of valve-actuating mechanism, which, while being extremely simple in construction, shall be reliable and positive in its action."

How it Works

Patent no. 951,965 was awarded to Valda W. Potter on March 15, 1910. The design is relatively simple, yet effective. A gear on the end of the crankshaft (c) meshes with and spins a "cam wheel" (d), which consists of a larger gear with a cam recessed into its face. The cam then actuates one of two levers (e), depending on which stroke the engine is on. The lever being actuated then forces a rod (f) back and forth, pushing and pulling an arm (g1) on yet another lever (g3). This lever is the final link in the mechanism, attached to the stem of the intake/exhaust valve to open and close it.

An interesting feature of this design is the interchangeability of the cam wheels, which allowed reverse rotation of the engine. This is accomplished in just a matter of minutes by removing the nut (e1) on the shaft of the first lever (e), removing the necessary parts, switching the cam wheels and reinstalling said parts.

Know of an interesting patent? Contact Gas Engine Magazine at:?1503 S.W. 42nd St., Topeka, KS 66609-1265;


Gas Engine Magazine A_M 16Gas Engine Magazine is your best source for tractor and stationary gas engine information.  Subscribe and connect with more than 23,000 other gas engine collectors and build your knowledge, share your passion and search for parts, in the publication written by and for gas engine enthusiasts! Gas Engine Magazine brings you: restoration stories, company histories, and technical advice. Plus our Flywheel Forum column helps answer your engine inquiries!

Be sure to take advantage of the Square Deal Subscription Program.

  • No Missed Issues.

  • No Renewal Notices.

  • No Additional Cost.

The Square Deal Subscription Program is designed as a paperless transaction with automatic renewals at a preferred low rate.   With advanced electronic notification, a 100% satisfaction guarantee and an easy opt-out plan, the Square Deal Subscription Program is the best value, risk free, eco-friendliest way to subscribe.

Facebook YouTube