A Revolution in the Common Car Engine

No, pun intended. A company named Rotoblock has taken a 40-year design and revamped it for use in today's demanding lifestyle. The technology, known as Oscillating Piston Engine has many advantages and practical applications.

While the theory of operation is fairly straight forward, trying to explain it is best accomplished with pictures. These steps, straight from the Rotoblock Site, offer a great explanation.

Unlike that of the standard internal combustion engine, the current ROTOBLOCK Oscillating Piston Engine design incorporates four pairs of pistons.


Each of these eight pistons is alternately attached, through two opposed oscillating adjacent thrust discs, to two coaxial drive shafts extending from the center of one face of the cylinder block.


Each piston is attached to a single disc such that four non-adjacent pistons are rigidly affixed to the upper disc and the remaining four to the lower disc. Each concentric shaft is attached, respectively, to the connecting discs. The discs, in turn, couple the motion of the oscillating pistons to a single crankshaft, via the coaxial shafts, and a dual scotch yoke mechanism.

Each piston is a segmented toroidal section traveling within the closed toroidal chamber of the rotating cylinder block. The combustion chamber is formed between each pair of pistons as the oscillating cycle continues.


The round cylinder block containing the pistons, connecting discs and coaxial output shafts is free to continuously rotate in a counter clockwise direction. It is caused to revolve 90° for every complete revolution of the rotating crankshaft. This action is accomplished by a four-to-one ratio gear reduction mechanism that couples these two components together.

During operation, the entire engine block rotates which moves pairs of spark plugs, intake ports and exhaust ports to the proper firing chamber.

According to the website, it can be utilized in anything from RC cars to family sedans. It can also be configured to run on alternative fuels like E85 and Hydrogen.

There are no official plans for mass production as of yet, however Rotoblock has announced a partnership with Apollo Energy Systems to help develop a hybrid drive train.

From : Rotoblock

George Delozier
Automotive Innovations