The Tomsk company "Tekhnologiya Market" has developed a piston engine scheme that allows increasing the piston stroke without increasing the overall dimensions of the power plant. The design is even suitable for steam and pneumatic drives.
The main difference is the modified mechanism for converting reciprocating motion into rotation. In traditional piston engines, the piston stroke is limited by an eccentric.
In the new design, the rods interact with the cam not with their ends, but with their side surface. For this purpose, the rods have a variable cross-section along their length.
That is, now the length of the working stroke depends almost solely on the length of the cylinders, and not on the dimensions of the motion conversion mechanism.
This allows increasing the displacement and torque without significantly increasing the engine's mass and size.
According to the developers' concept, the new engine architecture will allow creating compact power plants with high torque.