The inventor describes in this patent an internal combustion engine working on the following cycle:
Air, or other mixture of air and a neutral gas, is drawn into the cylinder on the out-stroke and compressed on the in-stroke until its temperature far exceeds that of the igniting point of the fuel employed; the fuel - gaseous, pulverised or liquid - is then gradually injected into the cylinder in a state of fine subdivision and ignites, the expansion preventing the pressure due to combustion from rising above that at the beginning of the stroke.
At a certain part of the out-stroke the fuel supply is cut off just as the steam supply is cut off in steam engines, and the combustion gases expand during the remainder of the stroke down to or below atmospheric temperature and pressure.
The invention provides for the prevention of an excessive pressure by injecting water spray during the first part of the compression stroke, and the compression may be carried out in two stages, first by a pump into a reservoir whence it is drawn into the motor cylinder and further compressed, and the products may be expanded twice.
The invention is described as applied to a single-acting engine in which coal dust is supplied to the cylinder through a rotary chambered valve from a hopper above; the products escape through an equilibrium valve. The governor throws a valve between the hopper and rotary valve out of gear when the speed is excessive. The starting of the engine is effected by compressed air.
Another form of engine comprises of two single-acting motor cylinders with a double-acting cylinder of large dimensions, which serves as a compression pump, at one end, and a low-pressure expansion cylinder at the other end.
A third form consists of a two-cylinder single-acting engine worked by liquid fuel. The air is drawn in through the exhaust valve, and a needle spraying valve for the liquid fuel is actuated by a tappet gear controlled by the governor. The engine can be started by the introduction of an explosive into the cylinder, and the cool exhaust gases may be used for cooling purposes.