Abstract: A spark plug for use in a combustion engine, which includes a spark plug body defining a central cavity; a electrode disposed within the cavity; a spring means disposed in one end portion of the central cavity; and a plate means operatively associated at one end with the spring means and adapted to communicate at its other end with the electrode whereby when the engine starts, the respective compression and explosion strokes move the plate means in one direction against the bias of the spring and in the opposite direction by the force of the spring, which in turn moves the other end of the plate in communication with the electrode in the same manner whereby combustion carbon collected on the electrode can be effectively removed.

Abstract: Otto internal-combustion engines having one injector respectively per cylinder for the internal mixture formation can be operated at full load or high partial load by fuel injection in the suction stroke of the piston and, at medium or low partial load, with a compression stroke injection. The compression stroke injection, which is advantageous in this load range, because of low average combustion space temperatures and the tendency to form deposits in the combustion space because of residues of liquid fuel and the resulting impaired operating conditions, can partially be carried out only to a limited degree.

Abstract: The present invention relates to ignition systems for internal combustion engines and, in particular, to a spark ignition system specifically adapted for two-cycle engines. An ignition system is provided which is able to avoid ignition plug smolder and electrode contamination by providing for self-cleaning of the ignition plug electrodes and ensuring complete combustion of an injected rich mixture of fuel/air in the vicinity of the ignition plug electrodes within a combustion chamber. This is accomplished by employing two distinct, yet interrelated, ignition plug firing systems. One such system causes an ignition plug to emit a spark of long duration when an air/fuel charge is present in the combustion chamber, thereby ensuring good combustion. The other system causes the ignition plug to emit a spark of short duration and of very high energy when little, or no, charge is present in the combustion chamber, thereby aiding in the self-cleaning of the electrodes of the ignition plug.

Abstract: A spark plug is provided for an internal combustion engine and includes a center electrode having a combustion chamber end and a ceramic insulator having an end portion over which an ablative coating is formed for removing contaminants deposited thereon. The ablative coating is capable of ablating completely during sustained operation of the spark plug.

Abstract: The invention relates to a method and arrangement for cleaning the spark plugs of an internal combustion engine automatically subsequent to the engine stopping and then, preferably, after an unsuccessful attempt to start the engine. Consequently, conditions for a successful starting attempt are made more favorable. Conditions preventing the start of an engine are often due to the presence of deposits on one of the spark plugs, these deposits preventing an ignition spark from being produced in the cylinder. The inventive method and arrangement solve this problem by burning clean the spark plugs immediately after the engine has stopped, and then preferably after the engine has failed to start. A detection means establishes whether or not the engine has started by sensing a suitable engine parameter, preferably engine speed, through a speed indicator.

Abstract: A spark plug having a heat pipe incorporated in the center conductor assembly in the insulator centerbore. The heat pipe is thermally non-conducting below a design temperature such that the firing end of the spark plug retains heat to burn off fouling deposits. Above the design temperature range, a vaporizable medium in the heat pipe vaporizes such that its change of state extracts heat from the firing end, the vapor moving to the cooler part of the heat pipe and condensing to release its heat by a change of state. Capillary means running the length of the heat pipe returns the vaporizable medium to the firing end of the heat pipe. This circulation of the heat pipe medium which occurs when the firing end exceeds the design temperature transfers heat from the firing end to prevent its overheating. The heat pipe in the insulator thus controls automatically the operative heat range of the spark plug.

Abstract: In an internal combustion engine, an injection hole is provided in the cylinder head to inject narrow streams of air towards the spark gap, particularly during idling and low load running conditions. The injected air is 5 to 30% by weight of the intake fuel-air mixture provided via the intake manifold and creates a swirl or turbulence thereby increasing combustibility. The hole is connected via a sub intake passage to the main air intake passage upstream of the venturi in the carburetor or between the venturi and throttle valve.

Abstract: A revolving piston combustion engine of trochoid type includes a housing composed of a shell with a multiarcuate inner surface and parallel ends and in which a polygonal piston is disposed to be eccentrically rotatable. Inlet and outlet passages are arranged in the housing. The shell is provided with at least one spark plug, the spark gap of which lies between at least two electrodes near the inner surface of the shell.