Abstract: A knock detection device that can not only detect knock accurately, but can also detect heavy knock quickly. Cylinder pressure is detected by a pressure sensor installed in each cylinder in an internal combustion engine. AS the occurrence or non-occurrence of heavy knock is determined based on the ratio between the maximum value of cylinder pressure fluctuation and the maximum value of cylinder pressure divided by a prescribed value, it becomes possible to detect the occurrence of heavy knock quickly. If it is determined that heavy knock has occurred, a knock suppression measure involving, for example, reducing the spark advance angle, is immediately applied, thus preventing damage to the internal combustion engine.

Abstract: An ignition coil, spark plug, and pressure sense assembly for an internal combustion engine are, in a preferred embodiment, integrated into a single assembly and mounted directly on a plug hole of an internal combustion engine. A pressure sense assembly is welded to a spark plug shell which serves as a pressure member. The pressure sense assembly includes a base plate onto which first and second pairs of strain gauges are printed using a thick film ink process (piezoresistive) in a full bridge arrangement. The geometry of the base plate and the fashion in which it is welded to the shell allow one pair of the gauges to function as strain sensing elements while the other pair can function for temperature compensation. Changes in the pressure in the combustion chamber deform the shell, causing a corresponding change in the bridge producing the pressure signal.

Abstract: An earth electrode is formed on the brim surface of the plug insulator and on the outer surface of the middle portion of the plug insulator along the axial direction. The earth electrode connected with one side of the combustion pressure sensor is provided on a whole surface opposite to a combustion pressure signal electrode. The earth electrode works also a shield member for shielding the high frequency noise generated inside the insulator. A part of the outer side of the earth electrode is covered by an insulating layer for insulating the earth electrode from the combustion pressure signal electrode. The combustion pressure sensor held between the insulator brim and electrode brim is given a prescribed compression load by a metal cylindrical bolt which presses down the electrode brim of the toward the combustion pressure sensor.

Abstract: Sensor apparatus for a multiple layer steel (MLS) cylinder head gasket measures combustion pressures for detecting engine conditions. A membrane is positioned at one end of an elongated metal tube, and the membrane end of the tube engages a cylinder bore boundary. A fiber optical sensor apparatus is fixed within the tube, and communicates with cyclic combustion events via the membrane. In one disclosed embodiment, optical wires from sensor apparatus situated at each engine bore are bundled into a common groove machined into an extended spacer layer radially outwardly of the conventional boundary of the gasket. The tube protects the sensor apparatus from damage of sealing stress on the gasket, and particularly at the bore perimeter. Each tube lies in a separate groove in the spacer layer that terminates at the bore boundary. A converter changes optical signals received from the apparatus into electrical signals for transmittal to a controller.

Abstract: A thick film resistor strain gauge is applied to a stainless steel shell portion of a spark plug. There are two preferable ways of applying a thick film resistor to the metal shell. In a first embodiment, the thick film resistor may be directly printed on to the shell portion with special screen printing equipment. In a second embodiment, the thick film resistor is printed and applied as a decal to the shell portion. The thick film resistors may be included in a quarter, a half, or a full wheatstone bridge strain gauge circuit. One of two embodiments of an automatic drift compensating circuit is used to determine the change in resistance experienced by the thick film resistors affixed to the spark plug. Either one of the automatic drift compensation circuits output a voltage signal which is proportional to the pressure changes occurring inside the engine cylinder into which the spark plug is threaded.

Abstract: An insulator includes a coil side cylindrical portion extending from a plug side cylinder portion in a direction departing from a combustion chamber. One end of the coil side cylindrical portion protrudes in the direction departing from the combustion chamber with respect to a primary winding and a secondary winding. A pressure sensing element is disposed next to the one end of the coil side cylindrical portion. The signal lines of the pressure sensing element are taken out of a casing without passing aside an ignition coil. Thus, the diameter of the casing does not increase. The output signal of the pressure sensing element is not adversely influenced by discharge noises generated from the ignition coil.

Abstract: An ignition coil, spark plug, and pressure sensor for an internal combustion engine are, in a preferred embodiment, integrated into a single assembly and mounted directly on a plug hole of an internal combustion engine. A hard spark plug shell serves as a pressure member and on which a strain gage is affixed. Changes in the pressure in the combustion chamber deform the shell, causing a corresponding change in the resistance of the strain gage. A bridge circuit or the like is used to measure the resistance change thereby providing a direct indication of cylinder pressure.

Abstract: An insulator includes a coil side cylindrical portion extending from a plug side cylinder portion in a direction departing from a combustion chamber. One end of the coil side cylindrical portion protrudes in the direction departing from the combustion chamber with respect to a primary winding and a secondary winding. A pressure sensing element is disposed next to the one end of the coil side cylindrical portion. The signal lines of the pressure sensing element are taken out of a casing without passing aside an ignition coil. Thus, the diameter of the casing does not increase. The output signal of the pressure sensing element is not adversely influenced by discharge noises generated from the ignition coil.

Abstract: A method of controlling detonation in an internal combustion engine is provided with the steps of: combusting a fuel and air mixture within a combustion cylinder; sensing a plurality of pressures at discrete points in time within the combustion cylinder; determining a pressure profile of the plurality of pressures; detecting detonation within the combustion cylinder; and acting upon the detonation, dependent upon where said detonation occurs on the pressure profile.

Abstract: A gas tight and simplified glow plug includes a combustion pressure sensor. The plug main body includes a cylindrical housing to be mounted in an engine head with one end side positioned at a combustion chamber side of the engine head. A cylindrical sheath tube is held in the housing with one end side exposed from the one end of the housing. A heating coil is received and held in the sheath tube. A central shaft acts as a rod-like electrode having one end side received in the sheath tube and an other end side exposed from other end of housing.

Abstract: A method and an arrangement for evaluating the combustion operations in an internal combustion engine with a model is suggested. The model takes a time-dependent transfer between pressure and structure-borne noise as a basis for the relevant low frequency oscillations and only individual components of the reconstructable pressure signal are used for the determination of combustion-relevant parameters and conditions. Independence of engine speed is achieved with the realization of the time dependency with an angular-dependent transfer function.

Abstract: The present invention relates to a method of locating the source of a knock, or more generally of a high-gradient self-ignition, appearing in a combustion chamber of an engine. According to the method, several pressure detectors are used, the pressure waves received by the detectors are recorded, the distance differences between the source of the knock and the various detectors are determined and the spatial location of the knock source in the chamber is deduced therefrom.

Abstract: An on-vehicle fiber-optic cylinder pressure sensor capable of detecting the pressure within a combustion chamber with precision has an optical fiber capable of converting a change in the pressure within a combustion chamber received on its outer surface on an engine gasket into a change in the light quantity passing therethrough. A light emitting device for emitting the passed-through light; a photosenses or senses the passed-through light of which the light quantity has been changed. A converter converts the light quantity of the passed-through light into an electric signal. A reference pressure setting apparatus sets a reference electric signal. A signal processor includes an apparatus for watching a corresponding reference electric signal to the reference electric signal included in the detected electric signal.