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:
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, 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:
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 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.
Abstract:
A device is disclosed for protecting a motor vehicle controller (10) against illicit exchange. The core of the invention is a function-inhibiting device (11, 12, 13, 27) associated with a connection between the controller (10) and the connecting element (20) of an electric supply line (21). The function-inhibiting device (11, 12, 13, 27) places the controller (10) and the connecting element (20) in a predetermined connecting position. This connecting position may only be interrupted in a non-destructive manner by supplying an unlocking code to the controller (10). When an attempt is made to interrupt the connection by force, the function-inhibiting device (11, 12, 13, 27) causes an irreversible interruption of the corresponding connection.
Abstract:
In a pressure sensor (11), the force is introduced via a membrane (14) and a plunger (18) onto a piezoresistive measuring element (21). The measuring element (21) is part of a monocrystalline silicon chip (20). The piezoresistive measuring element (21) is connected to the monocrystalline silicon chip in a half-bridge circuit or a Wheatstone bridge circuit. Also on the silicon chip (20) are a stabilizing circuit (23), an amplifier circuit (24) for the measurement signal picked up and electrical elements for temperature compensation of the zero point and sensitivity of the measuring element (21). Elements (51) for adjusting the functions with the help of additional connections are also present. The sensitivity and zero point of the pressure sensor in the fully assembled chip (20) can therefore be adjusted from the outside without laser adjustment. The pressure sensor (11) is also relatively small and compact.
Abstract:
Proposed is a high-voltage switch which carries out the function of an ignition-voltage distributor for an internal-combustion engine with static high-voltage distribution. The high-voltage switch comprises a cascade of semiconductor elements, this cascade being formed by patterning a single mono-crystalline silicon wafer (1) as a single chip with adjacent semiconductor elements (12) so that, when the pn transition zones (4) are irradiated with light, the breakdown voltage of the high-voltage switch is lowered.
Abstract:
A spark plug with a surface discharge section for internal combustion engines is provided with a spark plug barrel (11) with an annular earthed electrode (15), an insulating body (10) surrounded by the barrel (11) on a longitudinal section and a central electrode (19) housed in a through-hole (16) in the insulating body (10), and exposed on the combustion chamber side. The surface discharge section is formed between the central electrode (19) and the earthed electrode (15) along a discharge path on the surface of the insulating body (10). In order to obtain a low plug capacity with a highly dielectric discharge path, the insulating body (10) is provided at least in the end section of the combustion chamber side with at least two coaxial material layers (21, 22) which are totally or partially adjacent to one another in the radial direction and having highly different dielectric constance.