Abstract: A device for improving the thermal efficiency of an internal combustion engine by incorporating a hot gas jet ignition system and a burned gas purge system. The hot, high velocity gas jet generated by the system promotes rapid combustion and helps to insure better combustion of the fuel-air mixture. The invention accomplishes this by providing a spark plug or spark plug/adapter assembly with a mini-combustion chamber having an outlet nozzle. As the engine cycles into and through the combustion phase of operation, a hot, high velocity gaseous jet issues from the mini-combustion chamber and penetrates deep into the combustion chamber of the engine to ignite the main fuel-air mixture. The burned gases in the mini-combustion chamber are than purged by ambient air flow through an air inlet check valve communicating with the mini-combustion chamber during the next intake phase of the associated internal combustion engine cylinder or combustion chamber.

Abstract: An ignition system in an internal combustion engine having a cylinder housing with an air or water cooled region achieves multiple ignition. The ignition system includes at least a pair of spark plugs electrically connected in series and including a first spark plug mounted in the cylinder housing while being isolated electrically therefrom and a second spark plug directly screwed into a cylinder head of the cylinder housing. The first spark plug is mounted within the air or water cooled region of the cylinder housing, thereby maintaining such spark plug at a relatively constant temperature, and avoiding the problem of the two spark plugs being subjected to different thermal stresses.

Abstract: A spark plug with a heat pipe in the centerbore of the insulator thereof for controlling the operating temperature of the spark plug firing end automatically. A vaporizable medium in the heat pipe vaporizes when the load on the engine causes the temperature of the engine cylinder in which the spark plug is installed to rise into a temperature range in which damage to its firing end can occur. In that temperature range, the change of state of the vaporizable medium extracts heat from the firing end to prevent its overheating. The vapor pressure of the vaporied medium moves the vapor to a condensation zone where it condenses and releases its heat by a change of state. The condensate is returned to the vaporization zone by capillary means and the cycle is repeated as long as the firing end is in the overheating range of the spark plug.

Abstract: The invention relates to a pressurized ignition system for an engine. The service life of the igniter for the engine and high altitude operation of the engine are substantially reduced due to arc-over between the terminal of the igniter and the metallic shell of the igniter or the nearest ground. The service life of the igniter and associated components are affected by the hot, contaminated environment in which they operate. The present pressurized ignition system includes a chamber around at least a portion of the igniter and the chamber pressurized to a value of, for example, about two atmospheres for suppressing arc-over. The chamber is pressurized by an air compressor drivingly connected to the engine with the air cooled by an engine aftercooler. Pressurizing the chamber prevents contaminates from entering or collecting in the chamber and affecting operation of the system.

Abstract: A spark plug having a heat pipe located between the insulating core and the shell in the skirt portion thereof to vary the heat range automatically in response to the operating conditions of the engine in which it is fitted. The heat pipe is charged with a non-condensible gas and a working medium that undergoes a phase change at a predetermined design temperature to transport heat by means of an evaporation-condensation cycle from the firing end of the spark plug to prevent the overheating thereof. Below the design temperature, the heat pipe is thermally non-conducting such that the firing end of the spark plug is allowed to reach a temperature that will burn off combustion deposits that cause misfiring. In one embodiment, the heat pipe is fabricated as a separate integral annular element which is installed in the skirt of the spark plug during the manufacture thereof.

Abstract: A spark plug for igniting air-fuel mixtures, comprising: an elongated annular body with an axial bore; dividing the bore into a valve chamber and a compression chamber; and, a valve disk, slidingly disposed in the valve chamber, the valve disk being subjected to the operating pressure of the cylinder, the valve disk being pressed into a sealing position during compression, ignition and exhaust strokes, and being pulled into an open position during intake strokes, whereby unburned gases enter the combustion chamber during the exhaust strokes and additional air is pulled into the combustion chamber during the intake strokes, the unburned gases and additional air being injected back into the cylinder prior to each ignition to enhance subsequent combustions, the valve disk being substantially immune to damage from the successive shock loading to which it is subjected.

Abstract: An air injection system, in a spark plug, whereby air is injected into the combustion cylinder comprising a compression chamber disposed in the body of the spark plug, a tube extending coaxially through the center of the plug having an air inlet means and communicating with both the cylinder and the compression chamber, an air inlet means disposed in the body of the plug which meters air into the tube and cylinder, and a valve means which controls the air inlet means and reduces backpressure on the valve during compression and subsequent expansion of gases in the firing cycle.

Abstract: The invention relates to internal combustion engines operatable with ignition plug. For each engine cylinder, secondary air introduction means are provided which utilizes at least part of the intake passage, screw thread gaps around the plug. In this case, use of non-return valve means and of air precompression means is not made in any way.