Abstract: A knock sensor including a body, having a detection assembly able to measure vibrations, and a metal mount having a support ring on which the detection assembly rests, a peripheral casing to protect the detection assembly, made from a thermoplastic material applied by overmolding at least in part around the body. The mount includes a lower flange below the support ring and the lower flange is bored with attachment holes, which improve its sealing.

Abstract: An oil filled pressure sensor is provided. The sensor includes a drift-stabilized pressure sensing element mounted to and electrically isolated from a header body, the pressure sensing element immersed in an oil filled cavity and temperature stabilized for sensing pressure in the cavity without substantial signal drift. A method of fabrication is provided.

Abstract: A glow plug wherein a combustion gas prevention wall (67) extends radially outward on the outer circumferential surface of heater (10) such that when the heater (10) is viewed rearward from its forward end (10a) along the axial direction, the combustion gas prevention wall (67) closes an annular gap K1 at a position forward of annular membrane portion (63) of seal member (60). The combustion gas prevention wall (67) has an outer diameter D2 greater than the inner diameter D1 of forward end (136) of the housing.

Abstract: A glow plug includes a housing having an axial hold and provided with a screw portion, and a heater member inserted into the axial hole. The housing includes a front-end-side body portion extending to the front end side from a front end of the screw portion, and a gasket portion lying adjacent to a front end side of the front-end-side body portion and bent at a bent portion provided at a rear end thereof so that at least a rear end portion thereof extends in a direction intersecting a direction of an axis. The gasket portion includes a pressure contact portion in which a surface thereof located at an outer circumferential side is brought into pressure contact with a seat surface of an internal combustion engine when the screw portion is screwed into a mounting hole in the internal combustion engine.

Abstract: A spark ignition internal combustion engine includes: a compression ratio changing mechanism by which a volume of a combustion chamber varies; a cylinder internal pressure sensor that acquires a pressure signal of a pressure vibration inside a cylinder; and an abnormal combustion detector including a filter that passes the pressure signal, of a set frequency band among the pressure signal, and detecting an occurrence of abnormal combustion based on the pressure signal having passed through the filter. The abnormal combustion detector sets a frequency band of the filter based on a crank angle section in which abnormal combustion occurs and on a mechanical compression ratio.

Abstract: Embodiments may provide an engine knock monitoring system that may include an engine block including an engine block body and a cylinder wall defining at least a portion of a combustion chamber. A space may be defined between a top of the cylinder wall and a top of the engine block body. An engine knock sensor may be mounted to the engine block. A pressure pulse transmissive element may be disposed in the space and may be disposed in contact with an outside surface of the cylinder wall and an opposite inside surface of the engine block body.

Abstract: Systems and methods for monitoring health of one or more subsystems of a vehicle system are disclosed. At least one sensor can be operatively coupled to a vehicle subsystem having an operational signature and a control system is coupled to the at least one sensor. Using information provided by the at least one sensor, the control system is structured to generate a reference signature of the subsystem during a learning phase and an operational signature of the subsystem subsequent to the learning phase. Systems and methods for identifying the particular subsystem exhibiting degraded performance are also disclosed.

Abstract: A control system includes a cylinder pressure sensor (CPS) that senses a cylinder pressure of an engine and generates a CPS signal based on the cylinder pressure. A CPS failure detection module selectively generates a failure signal based on characteristics of the CPS signal in a knock frequency range. A status detection module generates a CPS status signal based on the CPS signal and the failure signal.

Abstract: A fuel injector comprising an injector body, a capnut, and a pressure sensor exposed to pressure changes in a combustion chamber in use, wherein the pressure sensor is accommodated within the capnut. Optionally, the fuel injector further comprises a signal cable external to the injector body to connect with the pressure sensor.

Abstract: A method for characterizing the knock-resistance of a fuel using a test engine is disclosed, wherein the time versus cylinder pressure curve of the test engine during combustion of the fuel in the test engine is determined. This pressure signal is, in turn, compared with the corresponding pressure signal of at least one standard fuel of known knock-resistance.

Abstract: A method of detecting during a combustion cycle a peak value of pressure in a cylinder of an internal combustion engine includes providing and installing on the engine body an accelerometer that generates an acceleration signal representing vibrations of the engine body. The acceleration signal is filtered by comparing the band-pass filtered replica of the acceleration signal to a threshold. When the threshold is surpassed, a pressure peak is detected and flagged.

Abstract: A method comprises steps for reconstructing in-cylinder pressure data from a vibration signal collected from a vibration sensor mounted on an engine component where it can generate a signal with a high signal-to-noise ratio, and correcting the vibration signal for errors introduced by vibration signal charge decay and sensor sensitivity. The correction factors are determined as a function of estimated motoring pressure and the measured vibration signal itself with each of these being associated with the same engine cycle. Accordingly, the method corrects for charge decay and changes in sensor sensitivity responsive to different engine conditions to allow greater accuracy in the reconstructed in-cylinder pressure data.

Abstract: The present invention relates to methods and apparatus for the evaluation of non-fuel components within a selected fuel with respect to engine knock performance. A non-fuel component such as a lubricant oil is now evaluated to determine onset of engine knock relative to baseline oil formulations that indicate relative low reactivity and optimum engine performance and those engine oils that exhibit relatively high reactivity and sub-optimum engine performance.

Abstract: The present invention relates to methods and apparatus for the evaluation of non-fuel components within a selected fuel with respect to engine knock performance. A non-fuel component such as a lubricant oil is now evaluated to determine onset of engine knock relative to baseline oil formulations that indicate relative low reactivity and optimum engine performance and those engine oils that exhibit relatively high reactivity and sub-optimum engine performance.

Abstract: A pressure-measuring device is situated in a chamber of an internal combustion engine. The pressure-measuring device has a housing, a force-transmitting element that protrudes partly from the housing at a chamber-side opening of the housing, and a pressure sensor that is situated in an interior space of the housing. The pressure sensor stands in effective connection to the force-transmitting element. In addition, a diaphragm is provided that seals the interior space of the housing, in which the pressure sensor is situated, against the chamber-side opening. The diaphragm, which is preferably fashioned as a metal diaphragm, has a force-transmitting segment that is oriented in an axial direction of the force-transmitting element. Moreover, the pressure sensor stands in effective connection with the force-transmitting element via the force-transmitting segment of the diaphragm.

Abstract: The invention relates to a method for characterising the knock-resistance of a fuel using a test engine, wherein the curve against time of the cylinder pressure of the test engine during combustion of the fuel in the test engine is determined and the determined pressure signals are compared with the corresponding pressure signals of a least one standard fuel of known knock-resistance.

Abstract: In an internal combustion engine with several cylinders, at least one cylinder is configured as a reference cylinder to which an active cylinder pressure sensor is allocated. A passive cylinder pressure sensor is allocated to each of the remaining cylinders. At least one actuating member is assigned to the cylinders. A crankshaft angle sensor is provided. During the quasi-stationary operating mode, the cylinder segment durations are equated, by an actuating member engaging in at least one actuating signal allocated to the respective cylinder. Furthermore, during the quasi-stationary operating mode, the measuring signal of the active sensor is allocated to the respective measuring signals of the passive sensors. As a result, the signal processing of the measuring signals of the passive sensors is adjusted depending on the respective measuring signals of the passive sensors captured during the quasi-stationary operating mode and on the allocated measuring signal of the active sensor.

Abstract: A pressure detection apparatus has a pressure-sensitive resistor whose first resistance varies according to pressure and a change of its own temperature, a temperature-sensitive resistor which has a same resistance-temperature coefficient as the pressure-sensitive resistor and whose second resistance varies according to the change of the temperature, a current source supplying first and second constant-currents to the pressure-sensitive and temperature-sensitive resistors respectively, and a pressure signal generation output section. The current source adjusts the first and second constant-currents so that when the pressure is an initial pressure, a reference first voltage appearing across the pressure-sensitive resistor and a reference second voltage appearing across the temperature-sensitive resistor become equal to each other.

Abstract: A pressure-measuring device is used for placing in a chamber of an internal combustion engine. The pressure-measuring device has a housing, a force-transmitting element in operative connection with a pressure sensor, and a centering element. The pressure sensor is placed, together with contact plates, on a centering section of the centering element, thereby making it possible to position the pressure sensor and the contact plates within the housing of the pressure-measuring device. The assembly of the pressure-measuring device is thereby facilitated, and a preassembly is possibly allowed.

Abstract: A combustion pressure sensor for detecting a combustion pressure in a combustion chamber of an engine is disclosed as having a housing mounted to an engine head in a gastight structure, a pressure sensor carried on the housing at a base end portion thereof, a transfer member having a pressure-receiving portion exposed to the combustion chamber to be axially slidable in the housing to transfer a combustion pressure from the combustion chamber to the pressure sensor, and a seal member disposed between the pressure-receiving portion of the transfer member and the housing in a gastight sealing structure to block an intrusion of combustion gas from the combustion chamber into the housing. The seal member includes a flexible portion with low rigidity that can stretch and absorb load acting on the pressure sensor when mounting the housing onto an engine cylinder.

Abstract: A device having at least one screw plug for screwing into a first tapped hole of a housing or housing part of the device, the at least one screw plug including a device for sealing, such as a sealing ring, for the connection to the housing in a manner forming a seal, e.g., against the escape of oil. Introduced into the screw plug is a second tapped hole by which a sensor is releasably connectable, e.g., is able to be screwed in. The screw plug includes an end stop for conducting acoustical waves and for the simultaneous mechanical limit for screwing in the screw plug.

Abstract: A combustion pressure sensor for detecting a pressure in the combustion chamber of an internal combustion engine includes a heat releasing member disposed between a housing and a pressure transmitting member at a position forward of a load detecting section and slidable relative to the pressure transmitting member for releasing heat through heat transfer from combustion gas, which has entered an axial hole of the housing from the combustion chamber, to the housing.

Abstract: A method for determining one or more cylinder pressure features for setting the combustion position in an internal combustion engine includes ascertaining a curve of a cylinder pressure or a curve of a cylinder pressure gradient with respect to a crankshaft angle, filtering the curve of the cylinder pressure or the curve of the cylinder pressure gradient using a filter, in order to eliminate a component of a pressure fluctuation brought about by the piston movement in the combustion chamber, and determining at least one cylinder pressure feature from the filtered curve.

Abstract: The invention concerns a method to determine the fuel composition of a fuel mixture from a first fuel and a second fuel for the operation of an internal combustion engine, wherein the first and the second fuel have different combustion rates and/or different specific energy contents and wherein the internal combustion engine has at least one pressure sensor in at least one combustion chamber, with which a temporal pressure curve and/or a pressure curve under conditions of angular synchronism is determined. Provision is made according to the invention for the composition of a fuel mixture to be determined from the temporal pressure curve and/or the pressure curve under conditions of angular synchronism of the gas pressure in the combustion chamber, of which there is at least one. A fuel mixture from fuels with different combustion rates exists, for example, in an alcohol-gasoline mixture. Alcohol has a faster combustion process than gasoline.

Abstract: A method of sensing the air/fuel ratio in a combustion chamber of an internal combustion engine that may be easily implemented by a respective low-cost device includes a pressure sensor and a learning machine that generates a sensing signal representing the air/fuel ratio by processing the waveform of the pressure in at least one cylinder of the engine. In practice, the learning machine extracts characteristic parameters of the waveform of the pressure and as a function of a certain number of them generates the sensing signal.

Abstract: A glow plug includes: a tubular body (2) having at one of its ends a plug head as well as a fixing zone including elements (12, 13) for being fixed in a bore, an arm (4) mounted on the body (2) of the plug at the end opposite to the plug head, and a pressure sensor (8) sealingly insulated from the corresponding cylinder. The arm (4) is fixed to an elastically deformable tubular zone (17) designed to project inside the cylinder. The pressure sensor (8) is mounted between the arm (4) and a support component (18) fixed inside the tubular body (2).

Abstract: A method for correcting a measured cylinder pressure of an internal combustion engine, in which a cylinder pressure sensor (16) is connected to a combustion chamber (4) via a duct (21), disturbing portions resulting from whistle oscillations being suppressed by determining an oscillation frequency of a gas oscillation caused in the duct (21) during a power stroke and filtering the measurement values of the cylinder pressure sensor (16) using a band-stop filter having the previously determined oscillation frequency.

Abstract: The invention relates to a device for measuring at least the pressure of a fluid present in a chamber (16), comprising a sensitive element (36) arranged in a housing (38), supported by a joint (10) inserted between two elements (12, 14) which form said chamber. According to the invention, the housing (38) is open in the direction of the chamber (16) and the sensitive element (36) is enclosed in a material (67) filling said housing.

Abstract: A pressure glow plug for a diesel engine has a glow plug body 2 for being inserted into a cylinder of the diesel engine, a heating rod 1 that is arranged in the glow plug body 2 and a pressure sensor 9 that is arranged between the heating rod 1 and the glow plug body 2 in such a way that the pressure in the combustion chamber of the cylinder that is transmitted by the heating rod 1 influences the pressure sensor 9. The heating rod 1 is arranged in the glow plug body 2 such that it can be displaced in an axially sliding fashion, namely by a corresponding sliding element, for example, a membrane 7 or seals 3.

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 combustion pressure sensor for detecting a combustion pressure in a combustion chamber of an engine is disclosed as having a housing mounted to an engine head in a gastight structure, a pressure sensor carried on the housing at a base end portion thereof, a transfer member having a pressure-receiving portion exposed to the combustion chamber to be axially slidable in the housing to transfer a combustion pressure from the combustion chamber to the pressure sensor, and a seal member disposed between the pressure-receiving portion of the transfer member and the housing in a gastight sealing structure to block an intrusion of combustion gas from the combustion chamber into the housing. The seal member includes a flexible portion with low rigidity that can stretch and absorb load acting on the pressure sensor when mounting the housing onto an engine cylinder.

Abstract: It is claimed that statements regarding cylinder pressure are obtained for optimization of the combustion process in internal combustion engines. The internal combustion engine is modeled with a plurality of model parameters (1 to 5) for this purpose. Once it has been acquired, a model alternating torque (MW) is compared to an actual alternating torque (IW). The model parameters are modified in accordance with the result of the comparison. The model yields realistic values of the combustion chamber value on the basis of the modified model parameters.

Abstract: The invention relates to a glow plug with integrated pressure sensor for measuring pressure in the combustion chamber of an internal combustion engine, where the shell of the glow plug has a section of reduced diameter on the side next to the combustion chamber and following a sealing cone, which section houses a glow coil and ends in a tip extending into the combustion chamber, and where the pressure sensor is positioned without cooling in the section of the glow plug next to combustion chamber. According to the invention the pressure sensor is subjected to pressure in radial direction, the glow coil of the glow plug or the electrical leads of the glow coil being guided towards the tip of the glow plug either by bypassing the pressure sensor or going through the pressure sensor.

Abstract: A spark plug having a combustion pressure detecting function, including a tip end portion in an axial direction of the spark plug capable of generating a spark discharge, a male thread adapted for attaching the spark plug to an internal combustion engine and a metal shell including, at a rear end side of the male thread, a brim portion projecting perpendicularly to the axial direction; an annular, flat gasket provided on a tip side of the brim portion; and a pressure sensor including a pressure-sensitive element, wherein the gasket has a Young's modulus E (kN/mm2) satisfying a relationship, 100?E?170.

Abstract: An in-cylinder pressure sensor outputs a signal corresponding to a change rate of an internal cylinder pressure of an engine. The output signal of the in-cylinder pressure sensor is filtered so that frequency components lower than frequencies that substantially compose an internal cylinder pressure required for controlling the engine are cut. The filtered output signal is integrated to determine the internal cylinder pressure. Thus, an internal cylinder pressure having no drift can be determined.

Abstract: A pressure sensor for measuring the pressure in a space acted upon by high pressure. The signals detected by the pressure sensor are supplied to evaluation electronics. A sensor diaphragm is accommodated on the end of the pressure sensor pointing towards the space acted upon by high pressure. The sensor diaphragm takes the form of a steel diaphragm, to whose back side a thin, metallic layer accommodating piezoresistive measuring elements is applied. The thin, metallic layer is contacted by transmission elements and connected to the evaluation electronics.

Abstract: According to the present invention, there is provided a pressure sensor unit (1) having a ring-like pressure sensing element (3), which is formed separately from a spark plug, in the state where a spark plug (100) has been attached a rear end of at least one of an inner cylinder member (6) and an outer cylinder member (5) in the direction of an axis (O) is located between the rear end of the pressure sensing element (3) and the rear end of a insulator (110) of the spark plug (standard section (SS)), while at the rear of the standard section (SS), no component of the pressure sensor unit (1) exists in an area inside the inner circumferential surface of the outer cylinder member (5) or its extended plate (EP).

Abstract: A knocking sensor comprises: a cylindrical body including a cylindrical portion and a supporting flange provided at an outer circumference of a lower end of the cylindrical portion; parts including an insulating member, an electrode plate and an annular piezoelectric element; and a fixing member including a tubular portion which comprises a holding portion protruding from an outer circumference of the tubular portion and is formed to insert into the cylindrical portion from an upper end of the cylindrical portion, the holding portion being elastically deformable to hold the parts, wherein the fixing member is fixed in the cylindrical portion by inserting the tubular portion into the cylindrical portion from the upper end of the cylindrical portion and wherein the parts are clamped and fixed between the supporting flange and the holding portion by holding the parts elastically with the holding portion, while the fixing member is fixed in the cylindrical portion.

Abstract: In an apparatus, a timing signal outputting unit outputs a timing signal every time interval. The time interval is shorter than a pulse time interval of the pulse signal. A first storage unit stores first information relative to each pulse time interval of the pulse signal. A second storage unit samples a value of the sensor signal each time the timing signal is outputted, and stores the sampled values so that the sampled values are associated with pieces of second information, respectively. Each of the pieces of second information is relative to each of sampled timings of the values. A calculating unit calculates a rotation angle of the rotation shaft corresponding to each of the values of the sensor signal based on a relationship between the first information and the pieces of second information.

Abstract: An improved force-measurement system utilizes active magnetostrictive sensors for generating a signal representative of a force, such as the weight of a person or thing on a seat within a motor vehicle, or the force applied to the horn sensor switch on a vehicle steering wheel. The active magnetostrictive sensor includes an excitation coil and a detection coil.

Abstract: A metallic cylinder head gasket for an internal combustion engine having at least one combustion chamber. The gasket includes at least one sheet-metal layer having at least one opening corresponding to the at least one combustion chamber of the internal combustion engine and at least one bore extending from the outer edge to the edge of the opening. A membrane, closing the bore at the combustion-chamber side is exposed to the gas pressure of the combustion chamber. A pressure sensor disposed in the sheet-metal layer is pressurized axially relative to the bore by movement of the membrane by the gas pressure of the combustion chamber.

Abstract: A spark plug for accommodating a pressure sensor. A connecting channel for extending a connecting line of the sensor extends in a housing and in a central section of the insulating core of the spark plug. As a result of this setup, the connecting line is extended in a protected manner in the region of the spark plug.

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: The pressure in a cylinder of a combustion engine is determined on the basis of vibrations in the engine which are generated during movement of the piston. A vibration signal (S) from a vibration sensor situated on a cylinder is filtered in the region about the piston top dead center position, at the transition from compression to expansion, in a special filter in which a half Hanning filter acts upon the vibration signal before and an exponential filter acts upon the vibration signal after the piston top dead center position. The filtered signal (U) is thereafter converted to a pressure signal (P) on the basis of an established relationship between vibration and pressure. The half Hanning filter has a significantly shorter time window (TH) than the exponential filter (TE). The filter cleans the vibration signal in an advantageous manner and makes more reliable pressure determination possible.

Abstract: An integrated LCC-based strain gage sensor, in which at least two LCC traces or strands run across a microcavity within the cylinder head gasket. In one aspect of the present invention, a system is provided comprising a signal source and a microcavity through which an input signal from the signal source passes and which alters the input signal as a result of a response of the microcavity to a strain. An LCC connects the microcavity and the signal source and an input signal propagates through the LCC. The microcavity may comprise one or more reflective surfaces which alters the input signal as a result of a change in a dimension of the microcavity. In another aspect of the invention, the microcavity produces an output signal that has an intensity or frequency different from that of the input signal upon undergoing a deformation.

Abstract: A pressure sensor having a sensor diaphragm for measuring pressure in combustion chambers of internal combustion engines, the pressure sensor being located in a housing, and high pressure and temperature fluctuations occurring in the combustion chamber. A heat shield made of a good heat-conducting material and provided with orifices is placed upstream from the sensor diaphragm to dissipate the heat to the housing surrounding the pressure sensor.

Abstract: In an internal combustion engine (10), exhaust gas leaves a combustion chamber (14) via at least one outlet valve (36) which is opened by an actuator after termination of a working stroke. A pressure value is determined, which characterizes the pressure of the gas in the combustion chamber during the working stroke. An actual value of the valve lift of the outlet valve (36) is determined, together with actual operating parameters of the internal combustion engine (10) which affect this opening stroke, and based on the determined actual valve lift of the outlet valve (36) and actual operating parameters of the internal combustion engine (10), an actual gas pressure in the combustion chamber (14) at the time of the opening of the outlet valve is calculated at least approximately.

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: A glow plug comprises a cylindrical housing having an inward protrusion extending radially inwardly, a threaded portion for screwing the glow plug in an engine plug hole and a sealing portion in a front side of the male threaded portion for airtightly engaging the housing with a given portion of the plug hole, a sheath having a rear sheath end portion airtightly fixed in the housing, a heater disposed in the sheath, a center electrode disposed in the housing and having a front electrode end portion electronically connected with the heater and mechanically connected with the sheath and an outward protrusion protruding radially outwardly, and a combustion pressure sensor having a pressure-sensitive element arranged between a front surface of the inward protrusion and a rear surface of the outward protrusion to generate an electrical signal in response to variations in stress applied thereto.

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.