Abstract: A piezoelectric measuring element comprises at least one bar with transverse effect which can be used with two conductor technology. Poles comprising the metallizations, electrodes and lines in the measuring element are embodied with one or more piezoelectric bars with transverse effect such that the electric capacitances thereof with respect to the housing are identical. There can be a completely symmetrical design of the poles. A capacitor from one pole to the housing can correspond to the difference in capacitance of both poles to the environment.

Abstract: The invention relates to a component for installation in force or pressure sensors, in particular in a glow plug. The component comprises a disc-type or punched-disc type measuring element consisting of a piezoelectric material, punched-disc type or disc-type electrodes that lie on either side of the measuring element. The electrodes have contact points for contacting conductors. The component comprises in addition a respective transmission body or several transmission bodies that are located outside the electrodes, on either side of the latter. The measuring element, electrodes and transmission bodies are held together mechanically by an external, electrically insulating film.

Abstract: A sensor unit for measuring a measurement variable in a medium, in particular in an aggressive liquid or gaseous medium, comprises a sensor that is arranged in a sensor capsule and has a sensor region that is arranged on a base body. In order to detect the measurement variable in the sensor region, a measurement opening is provided in the sensor capsule. On a side facing the measurement opening, the sensor region has a measurement surface that is provided with measurement electronics. An electrical supply line is provided on the sensor for the purpose of transmitting a sensor signal that is generated by the measurement electronics. A plated-through hole is provided in the base body. The plated-through hole is used to connect the measurement electronics to the electrical supply line via signals through the base body, on a base side of the sensor that faces away from the measurement opening.

Abstract: A pressure measuring device suitable for disposition in a chamber of an internal combustion engine. The pressure measuring device has a housing, a force transmitting element that is effectively connected to a pressure sensor, and a sensor cage that surrounds the pressure sensor. The sensor cage is connected to the housing by a circumferential weld seam only at one connection segment of the housing. In this way, it is possible to achieve a defined pre-tensioning of a metal diaphragm that is connected on the one hand to the sensor cage and on the other hand to the force transmitting element.

Abstract: The invention relates to a sensor unit for measuring a measurable variable, especially in an aggressive medium. Said sensor unit comprises a sensor which is disposed in a sensor casing and is provided with a sensor zone located on a base. In order to detect the measurable variable in the sensor zone, a measuring hole which allows the medium to advance directly to the sensor zone is provided in the sensor casing. A side of the sensor zone that faces away from the measuring hole is equipped with a measuring surface which encompasses measuring electronics. An electrical feeder is provided on the sensor in order to transmit a sensor signal generated by the measuring electronics. The sensor is sealingly arranged on a sealing surface located on the sensor casing in such a way that the measuring surface is isolated from the medium. A mechanism is provided by means of a which the sensor can be disconnected from thermally and/or mechanically induced changes in the sensor casing.

Abstract: A sheathed-element glow plug is used to be situated in a chamber in an internal combustion engine. The sheathed-element glow plug has a housing, a pin-shaped heating element, which extends partially from the housing and a pressure sensor which is situated in an inner chamber of the housing. A prestressing sleeve is provided, in this context, which applies a prestressing to the pressure sensor.

Abstract: A sensor unit for measuring a measurement variable in a medium, in particular in an aggressive liquid or gaseous medium, comprises a sensor that is arranged in a sensor capsule and has a sensor region that is arranged on a base body. In order to detect the measurement variable in the sensor region, a measurement opening is provided in the sensor capsule. On a side facing the measurement opening, the sensor region has a measurement surface that is provided with measurement electronics. An electrical supply line is provided on the sensor for the purpose of transmitting a sensor signal that is generated by the measurement electronics. A plated-through hole is provided in the base body. The plated-through hole is used to connect the measurement electronics to the electrical supply line via signals through the base body, on a base side of the sensor that faces away from the measurement opening.

Abstract: A piezoelectric measuring element comprises at least one bar with transverse effect which can be used with two conductor technology. Poles comprising the metallisations, electrodes and lines in the measuring element are embodied with one or more piezoelectric bars with transverse effect such that the electric capacitances thereof with respect to the housing are identical. There can be a completely symmetrical design of the poles. A capacitor from one pole to the housing can correspond to the difference in capacitance of both poles to the environment.

Abstract: A sheathed-element glow plug is used to be situated in a chamber in an internal combustion engine. The sheathed-element glow plug has a housing, a pin-shaped heating element, which extends partially from the housing and a pressure sensor which is situated in an inner chamber of the housing. A prestressing sleeve is provided, in this context, which applies a prestressing to the pressure sensor.

Abstract: A piezoelectric measuring element (9) consists of at least two piezoelectric crystals (1) showing a transversal effect for the measurement of axially acting forces and/or pressures as well as to a pressure or force sensor comprising said element. The crystals (1) with transversal effect having an opposite polarization (4) to each other are attached to each other by means of a lateral electrode (12). In this manner, if n crystals (1) are attached to each other, a single multi-layer measuring element (9) is obtained with a stability under load which is n-times that of an individual crystal. Preferably, the electrodes extend alternately into the two force-absorbing end faces (3) of the crystals. Such measuring elements can be fabricated from wafers (15) in a cost-effective manner. A compact multi-layer measuring element prepared in this way can be easily mounted in a sensor, particularly a force or pressure sensor, without the risk of inclination.

Abstract: An acceleration-compensated pressure pick-up, for example for the measurement of dynamic processes in gaseous or liquid media, comprises an external housing and a pre-assembled inner part having a flange at its assembly end. The inner part is securely fixed to the housing only at the flange. A first mass is connected via a first resilient connection to the flange, and a second mass is connected to the flange via a second resilient connection. A first measurement crystal is inserted under pre-tension between the two masses. A third mass and a compensation crystal are arranged between the first measurement crystal and the second mass, and the compensation crystal is electrically connected in opposition to the first measurement crystal. The two rigidities of the resilient connections and the three masses are matched so that the measurement values which can be determined at the crystals due to an axial acceleration acting on the housing compensate each other.

Abstract: The invention relates to a component for installation in force or pressure sensors, in particular in a glow plug. The component comprises a disc-type or punched-disc type measuring element consisting of a piezoelectric material, punched-disc type or disc-type electrodes that lie on either side of the measuring element. The electrodes have contact points for contacting conductors. The component comprises in addition a respective transmission body or several transmission bodies that are located outside the electrodes, on either side of the latter. The measuring element, electrodes and transmission bodies are held together mechanically by an external, electrically insulating film.

Abstract: The invention relates to a pressure sensor (1), comprising a housing (2), a housing element (3) which may be exposed to a pressure chamber (10), mounted on the housing (2) by means of a metallic membrane (5) and a measuring cell (4) which can indirectly measure a pressure acting on the housing element (3) and transmitted to the measuring cell (4) as a force resulting therefrom. According to the invention, said pressure sensor (1) comprises a housing element (3) embodied as a pin and projects out of the housing (2). The advantage of such an arrangement is only a small drilling to a pressure chamber (10) need be provided, in order to carry out a pressure measurement. The pin (3) need only be so long that the front end thereof, in the assembled state, approximately reaches the wall (11) of the pressure chamber (10).

Abstract: The invention relates to a sensor unit for measuring a measurable variable, especially in an aggressive medium. Said sensor unit comprises a sensor which is disposed in a sensor casing and is provided with a sensor zone located on a base. In order to detect the measurable variable in the sensor zone, a measuring hole which allows the medium to advance directly to the sensor zone is provided in the sensor casing. A side of the sensor zone that faces away from the measuring hole is equipped with a measuring surface which encompasses measuring electronics. An electrical feeder is provided on the sensor in order to transmit a sensor signal generated by the measuring electronics. The sensor is sealingly arranged on a sealing surface located on the sensor casing in such a way that the measuring surface is isolated from the medium. A mechanism is provided by means of a which the sensor can be disconnected from thermally and/or mechanically induced changes in the sensor casing.

Abstract: An acceleration-compensated pressure pick-up, for example for the measurement of dynamic processes in gaseous or liquid media, comprises an external housing and a pre-assembled inner part having a flange at its assembly end. The inner part is securely fixed to the housing only at the flange. A first mass is connected via a first resilient connection to the flange, and a second mass is connected to the flange via a second resilient connection. A first measurement crystal is inserted under pre-tension between the two masses. A third mass and a compensation crystal are arranged between the first measurement crystal and the second mass, and the compensation crystal is electrically connected in opposition to the first measurement crystal. The two rigidities of the resilient connections and the three masses are matched so that the measurement values which can be determined at the crystals due to an axial acceleration acting on the housing compensate each other.

Abstract: The invention relates to a pressure sensor (1), comprising a housing (2), a housing element (3) which may be exposed to a pressure chamber (10), mounted on the housing (2) by means of a metallic membrane (5) and a measuring cell (4) which can indirectly measure a pressure acting on the housing element (3) and transmitted to the measuring cell (4) as a force resulting therefrom. According to the invention, said pressure sensor (1) comprises a housing element (3) embodied as a pin and projects out of the housing (2). The advantage of such an arrangement is only a small drilling to a pressure chamber (10) need be provided, in order to carry out a pressure measurement. The pin (3) need only be so long that the front end thereof, in the assembled state, approximately reaches the wall (11) of the pressure chamber (10).

Abstract: A piezoelectric measuring element (9) consists of at least two piezoelectric crystals (1) showing a transversal effect for the measurement of axially acting forces and/or pressures as well as to a pressure or force sensor comprising said element. The crystals (1) with transversal effect having an opposite polarization (4) to each other are attached to each other by means of a lateral electrode (12). In this manner, if n crystals (1) are attached to each other, a single multi-layer measuring element (9) is obtained with a stability under load which is n-times that of an individual crystal. Preferably, the electrodes extend alternately into the two force-absorbing end faces (3) of the crystals. Such measuring elements can be fabricated from wafers (15) in a cost-effective manner. A compact multi-layer measuring element prepared in this way can be easily mounted in a sensor, particularly a force or pressure sensor, without the risk of inclination.

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 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 sensor to reduce the loads due to different thermal expansions between a chip containing the sensing element, said chip preferably consisting of silicon, and the housing, typically made of steel, which can falsify the measuring results. The chip includes central and lateral fixations, which are mechanically decoupled from each other and are arranged on that end of the sensing element where the force application occurs.