The Oscillating Piston Valve  Engine
  Bore: .500"  Stroke: .750"  Flywheel Dia.: 2.000"

The Oscillating Piston Valve Engine is sometimes called a "no-valve" engine, but every engine must have some method of admitting and exhausting the steam or air driving it.   In this engine this is accomplished via a "flat" on the piston and the linkage to the crankdisk which oscillates the piston    +/- 30 degrees such that the flat alternately allows air or steam into and out of the top of the cylinder with each revolution. This engine incorporates a 3/8" aluminum base, 3/4" aluminum bearing stand and  a hollow 1/2" diameter aluminum piston. The flywheel, crankdisk, links and cylinder assembly are brass. Steel   and/ or drill rod are used for the crankshaft and cylinder supports. Small details like the decorative flywheel and angled bearing stand give this model a clean symmetry that displays well. It runs well on 5-8 psi of air and the unique motion of the linkage mechanism which oscillates the piston as it travels up and down as well as driving the rotary motion of the crankdisk and flywheel is quite interesting to watch. 

The single acting cylinder simplifies construction, and with the valving being integrated with the piston, the need for a more complicated eccentric/linkage/valve assembly is avoided. Construction is straightforward and within the scope of most benchtop machine tools as well.

Overall dimensions are apprx. 2" W x 3 1/4" H x 4-1/8" L (excluding wood base).

The plan set consists of 6 pages of drawings and 4 pages of construction notes for $10.00 (US postage paid). Please see the general info. page and order page for more detailed information on plan sets.

To view or download a video clip of this engine running, click on the "Video" button below. (3.4MB, apprx. 44 seconds, .wmv format)



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