Kistler Holding Ag

K.k. Holding Ag

Stefan Brechbühl

Peter Wolfer

Claudio Cavalloni

Ernst Pletscher

Dieter Karst

Paul Furter

Simon Brunner

A glow plug adaptor for pressure measurement in a combustion chamber of an internal combustion engine includes an adaptor sleeve attached to an adaptor head that contains a pressure sensor with a diaphragm. A sealing shoulder can be screwed into an opening in a combustion chamber to provide a pressure-tight seal and permit passage of signal conductors from the pressure sensor through the adaptor sleeve. The adaptor head is tapered at the proximal combustion chamber end, and in the adaptor head a cavity is formed in such a way that the cavity is bounded by the diaphragm of the pressure sensor mounted therein and by a closed end wall of the adaptor head.

Glow-plug adaptor for pressure measurements

The invention describes membrane protections for a sensor having a membrane, which membrane protection does not increase the external diameter of a sensor and can be easily removed from a hole in which the sensor is installed. The membrane protection can be fastened to an inner surface of a front region of a sensor using a clip system and thus forms a unit with the sensor. The membrane protection for a sensor which can be screwed into a hole of an installation part and is provided with a membrane in the front region. The membrane protection has a clip system in order to be internally fastened in the front region of such a sensor. The sensor has a membrane protection which is internally fitted to the front region of the sensor using a clip system.

Membrane protection for a sensor having a membrane, and sensor having a membrane and membrane protection

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.

Pressure sensor with active and passive acceleration compensation

The invention concerns an important innovation for combustion engine research, whereby thermal shocks overlaid upon the pressure cycles are compensated. For this a diaphragm construction is proposed consisting of an annular plate and central plate, which is joined to an annular support in such a way that a bridge girder structure with double parallelogram support results. The position and thickness of the central plate are optimizable, and it serves as an actuator element for controlling the compensation process via the double parallelogram structure. At the same time, the central plate is raised to a significantly higher temperature level by controlled heat conduction paths. A novel thermal shock compensation is achieved by these two measures. Further improvement is possible by stepwise optimization of the central plate, by turning it on a lathe and comparing it in the test engine for example.

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Weinfelden, Switzerland

Stefan Brechbühl