Abstract:
In the pressure sensor proposed, the pressure is transmitted through a diaphragm (14) and a punch (18) to a piezo-resistive sensor element (19). The sensor element (19) is printed on the substrate of a hybrid circuit (22) and comprises several resistance tracks (38, 39) disposed one above the other in layers, in particular in the form of a pyramid. This makes it particularly simple to transmit the pressure into the sensor in a controlled fashion. In addition, the hybrid circuit is located at one end of the punch stop (23). The compact mounting of the hybrid circuit (22) and piezo-resistive sensor element (19) gives a relatively small, inexpensive design, but a large and relatively error-free sensor signal.
Abstract:
The invention concerns a pressure transducer (11) for the determination of the pressure in combustion chambers of internal-combustion engines, a piston (18) being located in a bore (12) in the transducer housing (10) with one end resting against a membrane (14) which seals off the aperture (13) at the end of the bore (12). The other end of the piston (18) acts on the sensor element (19) in such a way that the signal generated is proportional to the pressure in the combustion chamber. The housing (10) and piston (18) are both made of materials with the same thermal time constant. Thus the temperature distribution in the punch (18) and housing (10) are similar. Thermal stresses, which should distort the sensor signal, are therefore avoided.
Abstract:
Es wird ein Verfahren zum Steuern der Brennkraftmaschine vorgestellt, welches auf der Basis des von einem Drucksensor in mindestens einem Zylinder der Brennkraftmaschine und einem Drehwinkelgeber zur Erfassung des Drehwinkels der Kurbelwelle das von der Brennkraftmaschine erzeugte innere Moment berechnet, so dass eine schnelle und genaue Regelung des von der Brennkraftmaschine abgegebenen Moments Meff erreicht werden kann.
Abstract:
The invention proposes a process for determining the combustion point in the combustion chamber of an internal combustion engine so as to establish a parameter for influencing the combustion point. Thus, combustion chamber pressure and compression are detected and the difference between the two determined. The integral is then formed from the determined difference. This integral constitutes the starting point for determining a correcting variable for regulating the combustion point.
Abstract:
The invention relates to a method and a device for calibrating a pressure sensor (7) of a fuel dosing system of an internal combustion engine. Said fuel dosing system comprises a high-pressure pump (2) that delivers fuel from a low-pressure zone (ND) to a high-pressure zone (HD). The injectors (5) that dose the fuel from the high-pressure zone (HD) into the combustion chambers (6) of the internal combustion engine are controlled according to working characteristics. The dosing system further comprises the pressure sensor (7) that measures the pressure in the high-pressure zone (HD). The aim of the invention is to calibrate the pressure sensor (7) in such a manner that the offset-error can be reduced to a minimum. To this end, the pressure in the high-pressure zone (HD) is used as a reference pressure, the pressure in the high-pressure zone (HD) is measured by the pressure sensor (7) as the sensor pressure and the characteristic line of the pressure sensor (7) is corrected in such a manner that the difference from reference pressure and sensor pressure is reduced to a minimum.
Abstract:
In the pressure sensor (11) proposed, the pressure is transmitted through a diaphragm (14) and a punch (18) to a piezo-resistive sensor element (19). Since no precise mechanical alignment is necessary between the diaphragm (14) and the piezo-resistive element (19), various relatively inexpensive types of membrane of differing sensitivity can be used.
Abstract:
The invention concerns a pressure transducer (11) for the determination of the pressure in combustion chambers of internal-combustion engines, the transducer member (124) having an approximately centrally located depression (35). The piston (18) of the transducer (11) rests against the membrane (14) in the region (36) of the depression (35). In addition, the wall of the housing in the region of the apertures (13) covered over by the membrane (14) is thinner than the rest of the wall. By matching the shape of this part (38) of the housing wall and the depth of the depression (35) in the membrane (14), it is possible to compensate for the so-called thermal-shock error. The construction of the transducer (11) is simplified, thus enabling it to be manufactured inexpensively. Measurement errors which occur because of the temperature drop in the region of the membrane (14) and at the membrane end of the housing are eliminated.
Abstract:
Proposed is a silicon chip for use in a force-detection sensor. The chip has circuits (22), piezo-resistive elements (21), an intermediate element (36) and a force-application zone (23). The chip (20) is mounted on a support (38). The piezo-resistive elements (21) are disposed in a zone of high mechanical stress and the circuits (22) in a zone of low mechanical stress. The stress distribution within the chip (20) is modified by, for instance, grooves (122) in the chip.