Rand cam engine

The Rand-cam engine is a pistonless rotary engine.

The engine functions by using two opposing and identical disc-shaped rotors that are offset by 90 degrees around the central shaft. These rotors have a sinusoidal side proflie with two "bumps" and two "valleys". Both rotors turn in the same direction within the housing and are separated by a central section, inlaid in this central section are 12 vanes that can slide between one or the other rotor housing but do not turn with the engine's rotation. Since both rotors are offset and opposed, the straight-line distance between the two rotors is always the same, this allows for the vanes to move from one side to the other without breaking. The rotors are also called Cams, due to the camming action they use to move the vanes, this is the origin of the name

As opposed to a wankel engine which has a moving combustion chamber, the rand-cam engine's combustion chamber is fixed due to the stationary nature of the vanes, yet varies in size due to the rotor's motion.

The advantage of the rand-cam engine is its compactness and power output. Whereas a 4-cycle piston engine's piston only fires once every other turn of the crankshaft, and a wankel engine fires once every turn of the e-shaft; a Rand-cam engine fires 24 times per revolution of its main shaft. It can also achieve higher compression ratios which allow it to burn diesel fuel, something a wankel engine cannot do. The engine is currently under development by the US based company Regi U.S., Inc and has reportedly reached the prototype stage. According to their published information, the prototype will deliver 42 bhp from a unit only 6 inches wide by 6 inches long and can run on Ethanol, Natural Gas, Diesel, Propane and Hydrogen. There are immediate plans to demonstrate the engine, the first intended users are military contractors.