Kistler Holding Ag

K.k. Holding Ag

Kistler Instrumente Ag

Kristal Instrumente Ag

Paul Engeler

Peter Wolfer

Hans Conrad Sonderegger

Christof Sonderegger

Christopherus Bader

Max P Waser

Ulrich Staiger

Claudio Cavalloni

Hans-Conrad Sonderegger

Georges Schaffner

Hans Ulrich Baumgartner

Ernst Pletscher

Andreas Kirchheim

Reinhard Staub

Leo Amstutz

Mario Giorgetta

Daniel Otter

Peter Charles Tack

Andreas Ullrich

Andrew Crawford

Alex Weber

Reinhard Bosshard

Ulrich Dubendorfer

Reto Calderra

An adapter for pressure sensors for monitoring long-term cylinder pressures in internal combustion engines comprises a housing with a gas duct, a connection to a cylinder cover of an internal combustion engine, a rear opening of the gas duct from the housing with an apparatus for closing this rear opening in a gastight manner, and a connection for inserting a pressure sensor with a sensor membrane. The transition line of the opening in the gas duct, which is reached by the sensor membrane in the inserted state in order to be exposed to the gas pressure in the gas duct, is on a plane. The transition line forms the transition from the contour of the gas duct to the connection to the sensor. There is a continuous transition from the sensor membrane to the contour of the gas duct.

Adapter for pressure sensors for carrying out long-term cylinder pressure monitoring on internal combustion engines

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.

Piezoelectric measuring element with transverse effect and sensor comprising such a measuring element

A measuring arrangement for assembly on or in a tool, in particular, in an injection moulding tool, comprising two or more sensors for the simultaneous measurement of measured parameters, each sensor generating a measurement signal in the operating state, at least two measurement signals being of different types from each other. The measuring arrangement comprises a signal converter with an output interface, all measured signals being converted into the same type of output signal in the signal converter. Said output signals can be transmitted through the output interface by means of a detachable signal line to an analytical unit.

Measuring arrangement

A measuring system includes a piezoelectric sensor, two or more charge amplifiers that are provided with different amplification settings and one respective output, and a signal splitter which is disposed between the sensor and the amplifiers. A charge signal received by the piezoelectric sensor is subdivided into two or more partial signals on the signal splitter during a measurement, and each of two or more partial signals is fed to one of the charge amplifiers, is processed therein, and is finally fed to the outputs. The signal splitter preferably encompasses two or more capacitors. The inventive measuring system is used above all for measuring forces, pressures, extensions/expansions, moments, or accelerations.

Measuring system comprising variably sensitive outputs

A strain gauge measures elongation and compression at a surface of a component. The strain gauge comprise a housing having a fixation configured to attach the strain gauge to the surface to be measured, a connector for contacting a measuring cable, at least two support surfaces at the housing for securely bearing on the surface to be measured. At least one of the support surfaces is provided with a transduction element and with a measuring element for measuring shearing forces. The measuring element is connected by an internally disposed cable to the connector and to a module that comprises that at least one support surface provided with the measuring element pre-assembled together with the transduction element.

Strain gauge

A high-pressure sensor comprises an inner part, a housing and a sealing system located between the inner part and the housing for sealing the high-pressure sensor. The inner part has a shaft having an end face resting, by means of a clamping force, at least along a sealing line on a support surface at a projection on the housing. Each of the projection and the shaft has an inner surface and an outer surface. The support surface is arranged in an acute angle with respect to the inner surface of the projection. The shaft by means of the clamping force is supported on the housing along a support line whereby the sealing effect can be increased with increasing pressure.

High-pressure sensor with sealing system

A production mold with piezo-transducers and associated signal processing amplifiers located inside it are housed in a tightly sealed, electrically shielded unit. The piezo-transducers are linked by a stranded conductor only insulated, which is cut to length in situ and led inside the shielded unit to a high-insulating terminal of the amplifier. There is no longer any need to use shielded cables between the piezo-transducer and amplifier.

Piezo-transducer and cabling configuration

The invention is an acceleration-compensated pressure transducer having only one signal crystal array joined by two masses and connecting elements to an inner part having a flange. The installation housing of the pressure transducer is joined to the flange and touches the inner part of the pressure transducer at no other point. Hence, the inner part constitutes a freely vibrating element, which with the masses and the stiffnesses optimized, measures only the pressure signal.

Acceleration-compensated pressure transducer

A pressure sensor having a disk-shaped sensor body which includes a pressure space for the medium to be measured. A bolt element in the pressure space forms a tubular pressure gap of small volume. The bolt element also forms a heat accumulator before the pressure transducer surface of the sensor body and acts on a temperature compensating element to narrow the temperature swings in the sensor due to temperature shocks. The new pressure sensor may be used for hot combustion gases and for fuels and other liquid or gaseous substances. In the application for monitoring internal combustion engines, the pressure sensor is fitted between the combustion chamber and the indicator valve instead of after the indicator valve, making possible periodic blowing-through and hence the removal of all combustion residues and calibration measurement any time.

Pressure sensor for gaseous and/or liquid media of internal combustion

A device which is capable of measuring both the viscous injection/casting operation and the shrinkage during the solidification phase, using a suitable measuring device. For this a sensor is fitted in the mould at the critical point expected, with a measuring surface that is flush with the inner wall and is able to measure shear and compressive stresses, so that for the first time the shrinkage phenomenon becomes measurable. With this, a new dimension of quality monitoring becomes possible.

Device for detecting material stresses in mouldings and castings

A multicomponent force and moment measuring arrangement wherein shear forces are converted into moments and transmitted via tensile-compressive forces onto piezoelectric rod elements, while axial compressive-tensile forces are transmitted directly onto the same piezoelectric rod elements. With appropriate arrangement of the piezoelectric rods and their signal evaluation, transducers and dynamometers of entirely new type can be constructed, in which the necessary electronics package can be located between the piezoelectric rod elements for certain applications.

Multicomponent force and moment measuring arrangement

A method and a device for measuring the pressure in a tubular body, for example, in the nozzle of a plastics injection molding machine, in the injection pumps of diesel engines, in gun barrels and the like, makes use of electromechanical transducers of piezoelectric, piezoresistive or strain gauge type to detect the radial and tangential mechanical stresses .sigma..sub.r, .sigma..sub.t in the tube cross section. The output signals s.sub.r, s.sub.t of the transducers are fed to a signal processing facility consisting of a subtraction circuit (for transducers of like polarity) or an addition circuit (for transducers of unlike polarity). The output signal of the signal processing facility is proportional to the difference between the pressures inside and outside the tubular body and may be fed to a further evaluation facility, such as a pressure display or process control device. The invention makes possible the exact measurement of the pressure inside a tubular body without contact with the pressure medium, and excludes disturbing influences as may arise due to temperature gradients, longitudinal stresses and the like.

Method and device for measuring pressures in tubular bodies

A transducer, particularly for ballistic high pressure measurements, comprises an assembly body, with a shoulder sealing section and a sensor member, which can be received in a recess in the assembly body. The assembly body can be screwed into a component, e.g. a gun barrel, the measurement area on the sealing section being sealed. The assembly body has a tubular extension extending beyond the sealing section, which extension encompasses the sensor member on a cylindrical fitting face. The high sealing forces required for sealing the measurement area are kept remote from the sensor member. The measuring sensitivity of the transducer is therefore independent of the prevailing tightening torques. A cylindrical gap between the sensor member and assembly body provides additional insulation between the sealing forces and the prestress forces prevailing in the sensor member. The cylindrical gap is sealed against the pressure medium by a force fit or weld between the assembly body and the sensor member. A reception space can be provided ahead of the diaphragm section of the sensor member, which reception space can be formed by an annular section projecting from the diaphragm section, and can be provided with replaceable thermal and erosion protection devices.

High pressure transducer

A high pressure transducer, particularly for ballistic pressure measurements, with a sensor part, with a sealing part formed thereon and with a hollow mounting screw surrounding the sensor part with a clearance. The sensor part can be inserted together with the sealing part into a threaded mounting aperture in the component to be examined, whereby the sealing surface of the sealing part comes into sealing contact with a seating surface of the mounting aperture. The hollow mounting screw presses on the sealing part and produces the force necessary for sealing. The sealing surface of the sealing part is located somewhat ahead of a membrane portion while the sealing part is connected relatively elastically with the sensor part by means of a narrow web. The force flux lines produced by the sealing force are restricted in their effect substantially to the sealing part and do not reach the sensor element received in the sensor part; as a result thereof, a substantial independence of the measures values from the mounting conditions is attained.

A force transducer, particularly for the ballistic measuring of the combustion pressure in the cartridge case of a firearm, is disclosed which includes a force transmission element which rests with one of its front areas on the cartridge case. The force transmission element is surrounded on its exterior by an outer sleeve which also rests with its front area on the cartridge case. The front areas of the force transmission element and of the outer sleeve are exactly adapted to the curvature of the cartridge case by reaming after the transducer has been mounted in the firearm. With the combustion of the powder, the cartridge case expands and transmits its force to a sensor element via the force transmission element, with the sensor element being preferably in the form of at least one piezoelectric transversal quartz element which is held under pretension between the force transmission element and a basic receiver component. The spring rigidity of the force transmission element and the spring rigidity of the outer sleeve are matched in such a way that both parts yield essentially to the same extent to the pressures acting upon them in the axial direction of the transducer. The result is that the contact conditions of the cartridge case with the front area of the force transmission piston do not change appreciably after the expansion in comparison with the initial conditions so that a calibration curve of the force transducer which is independent of the installation can be supplied by the manufacturer.

Growing community of inventors

Frauenfeld, Switzerland

Paul Engeler