Rotoblock patented new Open internal combustion engine is radical departure from convetional receprocating engine technology

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.
Rotation of the cylinder block causes a pair of intake and exhaust ports, as well as two diametrically positioned* spark plugs, to regularly appear in the intervening spaces formed between the faces of the pistons as they oscillate backwards and forwards between the limits of allowed travel within the toroidal cylinder.

When in operation, the diametrically opposed* inlet ports in the cylinder block are supplied with a combustible fuel/air mixture through an attached intake manifold, such that the separating opposing piston pairs each draws in a fresh fuel/air charge mixture as the rotating cylinder block passes through the first of four combustion cycles.




The second

cycle begins as the same piston pairs reaches their limits of travel, reverse direction and proceed to compress the charge mixture captured between their faces.


Compression continues until the approaching piston faces reach their closest point at the end of their range of travel.



The third cycle starts with the appearance of the spark plugs in the intervening space between the moving pistons just at the point in the cycle when they make their closest approach to each other.


At this juncture, timed firing of the spark plugs ignites the compressed charge mixture confined between the faces of each of the two piston pairs.

The exploding fuel/air mixture is rapidly heated and expands, thereby forcing the opposing piston pair faces apart and, by so doing, produces the power cycle. The force applied to the separating pistons by the expanding gas is coupled, through the two connecting discs and coaxial drive shafts, to the scotch yokes, which, in turn cause the continuous rotation of the crankshaft and output shaft. As the cylinder block continues to rotate, the fourth cycle begins. Next, exhaust ports appear between the piston pairs coincident with their change of direction at the end of the power stroke. The approaching piston faces now expel the burnt exhaust gases through the exhaust ports. This brings to a close the final cycle of the four-cycle sequence.

The endless repetition of these four combustion cycles produces sixteen power strokes for each revolution of the cylinder block. Momentum stored in the inertial mass of the rotating cylinder block substitutes for the action of the flywheel found in conventional reciprocating engine designs. This feature adds to the simplicity the Rotoblock Oscillating Piston Engine, while simultaneously, permitting extremely smooth, vibration free operation.