Abstract: An internal combustion engine has at least one cylinder wall forming a cylinder, and at least one knock sensor held on a housing element. The knock sensor is fixed to a fastening point of the housing element. An intermediate chamber is provided in the radial direction of the cylinder between at least one section of the cylinder wall and the fastening point of the housing element arranged on a side of the cylinder wall facing away from the cylinder, a distance extending at least in the radial direction of the cylinder being provided as a result. At least one sound transmission bridge extends in the intermediate chamber, bridging the distance from the cylinder wall continuously to the fastening point, via which vibrations, on the basis of which knocking combustion can be detected by the knock sensor, are transferrable from the cylinder wall to the fastening point.

Abstract: A processing circuit is provided which includes at least an integrator circuit which uses a reference voltage set to have a predetermined magnitude as an operation reference and which integrates a detection signal so as to convert the detection signal into a voltage waveform and a base voltage adjustment circuit which is connected between an input terminal and an output terminal of the integrator circuit and which adjusts the magnitude of a base voltage that is a potential when the detection signal in an output signal output from the integrator circuit is not present.

Abstract: In accordance with the present invention, there is provided a method for producing a single LTGA crystal from a polycrystalline starting material prepared from a mixture of La2O3, Ta2O5, Ga2O3, and Al2O3, wherein a mixture having a composition represented by y(La2O3)+(1?x?y?z)(Ta2O5)+z(Ga2O3)+x(Al2O3) (in the formula, 0<x?0.40/9, 3.00/9<y?3.23/9, and 5.00/9?z<5.50/9) is used as the polycrystalline starting material, and a single LTGA crystal is grown using the Z-axis as a crystal growth axis. The grown LTGA single crystal is preferably subjected to a vacuum heat treatment. The single LTGA crystal grown by the method according to the present invention, which is highly insulative and highly stable, can be utilized in such applications as a piezoelectric element of a highly reliable combustion pressure sensor useful in measurement of a combustion pressure in a combustion chamber of an internal combustion engine.

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 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 pencil-type glow plug for a self-igniting internal combustion engine is described. The pencil-type glow plug includes a plug body in which a combustion chamber pressure sensor is integrated, and a bar-shaped heating element that protrudes out from the plug body at one end, into the combustion chamber of the internal combustion engine. A force-measuring element of the combustion chamber pressure sensor is accommodated behind the heating element, which moves axially under the influence of force. The force-measuring element is sealed against combustion chamber gases by a steel diaphragm made of a stainless precipitation-hardened maraging steel.

Abstract: A method and apparatus for measuring knocking in internal combustion engines employs a high temperature transducer, which transducer is mounted within a cylinder. The output of the transducer is solely related to pressure. The output signal from the transducer is directed to the input of a high frequency amplifier associated with a band pass filter. In this manner the combustion signal can be filtered out and one provides a signal which is only indicative of the knocking signal and of the knocking frequencies. This signal can be analyzed simply and effectively by the use of a processor such as a multimeter or a microprocessor. In a similar manner the processor can compare the combustion and knocking signal without the band pass filtering with the knocking signal with the combustion signal filtered out.

Abstract: The inventive circuitry on a semiconductor chip includes a first functional element having a first electronic functional-element parameter that exhibits a dependence relating to the mechanical stress present in the semiconductor circuit chip in accordance with a first functional-element stress influence function. The first functional element provides a first output signal based on the first electronic functional-element parameter and mechanical stress. A second functional element has a second electronic functional-element parameter that exhibits a dependence in relation to the mechanical stress present in the semiconductor circuit chip in accordance with a second functional-element stress influence function. The second functional element is configured to provide a second output signal based on the second electronic functional-element parameter and the mechanical stress.

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: The piezoelectric element of an engine knock sensor is held between upper and lower ring-shaped bases by two identical clips that extend through the piezoelectric element and engage each base. Each clip has a ring-shaped flange engaging a groove circumscribing the inner wall of one of the bases, with the flanges of the clips engaging opposite bases. Also, each clip has three legs that engage a groove in the opposite base. Each clip leg is disposed between two legs of the other clip.

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: To provide a combustion pressure sensor capable of reducing noises generated by the force in a rocking direction by making uniform the stress exerted onto the piezoelectric element; and a glow plug having the same.

Abstract: A glow plug comprising: a cylindrical housing; a heater member as defined herein; a conductive center pole as defined herein; a first piezoelectric element as defined herein; and a second piezoelectric element as defined herein, wherein each of said first piezoelectric element and said second piezoelectric element is subjected to a preload for compressing it in said axial direction and is arranged such that, when said center pole is displaced to a root-end side, a load to be applied to one of said first piezoelectric element and said second piezoelectric element for compressing the same in said axial direction increases whereas a load to be applied to the other for compressing the same in said axial direction decreases.

Abstract: A stacked body constituted by a first insulating sheet, a first terminal plate, a piezoelectric element, a second terminal plate, a second insulating sheet, a weight, and a disk spring is fitted over a cylindrical portion of a base, clamped and held between a nut and a flange portion of the base, and resin-molded. Annular partial electrodes having a width narrower than a radial width of the piezoelectric element are formed on front and rear surfaces of the piezoelectric element. The first and second terminal plates have annular portions formed so as to have annular shapes having an outside diameter and an inside diameter substantially equal to those of the partial electrodes, and are stacked such that the annular portions are placed in close contact with entire surfaces of the partial electrodes.

Abstract: An in-cylinder pressure detection device which is capable of ensuring stable detection accuracy irrespective of tightening torque applied in mounting the in-cylinder pressure detection device and thermal expansion of component parts of the same. A housing 21 has a top wall 22a and a bottom wall 22b opposed to each other, and is screwed into the body of an internal combustion engine. An inner member 24 extends through the housing 21 such that one end thereof projects into a cylinder C, and has a flange part 24b accommodated in the housing 21. A first piezoelectric element 11c is accommodated in the housing 21 and sandwiched between the bottom wall 22b and the flange part 24b in a preloaded state, for outputting a first detection signal q1 according to the in-cylinder pressure transmitted via the inner member 24.

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: A combustion pressure sensor for an internal combustion engine is provided. The sensor includes a sensing element such as a piezoelectric device sensitive to a physical load applied thereto to produce an electric signal indicative thereof and a bendable member. The bendable member is bent upon application of the combustion pressure in the engine to apply the physical load to the sensing element. Specifically, the physical load is applied to the sensing element which arises from the bend deformation of the bendable member, thus eliminating the need for a complete surface-to-surface contact between the sensing element and the bendable member. This results in a decreased unit-to-unit variation in sensitivity of combustion pressure sensors and ensures the stability of output characteristics of the combustion pressure sensor.

Abstract: A combustion pressure sensor for an internal combustion engine is provided. The sensor includes a sensing element such as a piezoelectric device sensitive to a physical load applied thereto to produce an electric signal indicative thereof and a bendable member. The bendable member is bent upon application of the combustion pressure in the engine to apply the physical load to the sensing element. Specifically, the physical load is applied to the sensing element which arises from the bend deformation of the bendable member, thus eliminating the need for a complete surface-to-surface contact between the sensing element and the bendable member. This results in a decreased unit-to-unit variation in sensitivity of combustion pressure sensors and ensures the stability of output characteristics of the combustion pressure sensor.

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: A knock sensor comprises a sensor body having a metallic shell including a cylindrical portion and a flange portion formed at an end of the cylindrical portion, an annular piezoelectric element fitted around the cylindrical portion and an annular weighting member fitted around the cylindrical portion to hold the piezoelectric element between the weighting member and the flange portion, and a resin-molded sensor casing arranged circumferentially around the sensor body. The resin-molded sensor casing includes a weighting portion located nearer to the weighting member than to the piezoelectric element with respect to an axial direction of the cylindrical portion, and at least the weighting portion of the resin-molded sensor casing is made of a resin containing at least one of metal powder and metal oxide powder and has a density of 2.0 g/cm3 or higher.

Abstract: A signal processing device is provided which is designed to process an output of a piezoelectric sensor to produce a signal which indicates a load applied to the piezoelectric sensor accurately without being affected adversely by leakage current occurring in the piezoelectric sensor and electrical disturbances. The signal processing device includes a differentiating circuit which differentiates the output of the piezoelectric sensor and an integrating circuit which integrates an output of the differentiating circuit to produce an output signal as a function of the output of the piezoelectric sensor. The frequency range of the output signal is selected based on a frequency range of the load applied to the piezoelectric sensor.