Vibro-meter Sa

Meggitt Sa

Felix Schmid

Jacques Perriard

Heinrich K Feichtinger

Bernard Broillet

Nicolas Clement

Beno&icirc;t Maillard

In a measuring device for the measurement of the brake torque on an aircraft landing gear, a connecting element that is transversally loaded by the brake torque is provided with measuring elements which produce a measuring signal in function of a deformation of the connecting element. In one of two preferred variants, the measuring elements are attached to the surface of a cavity in the connecting element, and in the second preferred embodiment, a corresponding sensor is introduced into the connecting element as a whole, the sensor being so designed that deformations affect its enclosure and deform the latter as well.

Brake-force-sensing device for vehicle running gears

In a measuring device for the measurement of forces in a vehicle undercarriage, more particularly of the brake torque on a vehicle undercarriage, e.g. an aircraft landing gear, a sensor is introduced into a hollow connecting element that is transversally loaded by said forces, which sensor produces a measuring signal in function of a deformation of said connecting element. Distance measuring elements which detect the distance of the inner wall of said connecting element from said sensor are used as measuring elements.

Force-sensing device for vehicle running gears

The seismic mass ( ) of an accelerometer that comprises at least one electromechanical transducer is stabilized in the direction perpendicular to the sensible axis by at least one laterally stabilizing element ( ) arranged between the electromechanical transducer ( ) and a structural element ( ). This stabilization eliminates or at least drastically reduces any distortions of the measurement results provoked by transversal accelerations.

Piezoelectric accelerometer with laterally stabilizing element

Pressure measuring instrument, comprising a mounting plate and a flexible separating element which is disposed in an opening of the mounting plate and fastened thereto, and which separating element is under the action of a measured pressure during the pressure measurement. In order to compensate errors of the pressure measurement due to accelerations, the pressure measuring instrument further comprises a reference body which is connected to said mounting plate via a suspension and comprises a reference surface facing a surface of said separating element, the reference body and the suspension being so designed that when the entire pressure measuring instrument is subject to an acceleration, the resulting displacement of the reference surface of said reference body is equal to the displacement of the surface of said separating element on account of the acceleration.

Acceleration compensated pressure measuring instrument

A method for manufacturing a device for contactless and digital measurement of a linear or angular condition of a first piece with respect to a second piece. A series of ferromagnetic encoding marks are provided onto a non-magnetic substrate of one of the pieces. The encoding marks are produced by a strongly local heating of the surface of a non-magnetic substrate of an austenitic steel stabilized by a metalloid in interstitial solution. Displacement, speed and acceleration of a linear or angular kind of one piece with respect to a second piece can thereby be measured with great accuracy.

Method for contactless digital measuring of the displacement or position

The seismic mass is fixed to the mounting base by a tension bolt. This bolt passes with an important play through an opening of a piezoelectric transducer arranged between the mounting base and the seismic mass. Under the influence of inertial forces which act perpendicularly to the axis of the bolt on the seismic mass, bending loads occur which result in an increase of the pressure at one side and in a decrease of the pressure at the other side of the piezoelectric transducer. The piezoelectric transducer has four electrodes mounted on its top face and four electrodes mounted on its bottom face so as to provide a biaxial accelerometer.

Biaxial accelerometer

The seismic mass is fixed to the mounting base by a tension bolt. This bolt passes with an important play through an opening of the piezoelectric transducer arranged between the mounting base and the seismic mass. Under the influence of inertial forces which act perpendicularly to the axis of the bolt on the seismic mass, bending loads occur which result in an increase of the pressure at one side and in a decrease of the pressure at the other side of the piezoelectric transducer. The transducer has halves polarized in opposite directions and subjected to pressures varying in opposite sense and electrodes covering the top and bottom surfaces of the halves, signals of the same polarity being induced under the bending loads. External influences which act uniformly on the transducer are compensated.

Accelerometer with piezoelectric element

The accelerometer comprising two piezoelectric transducers. A common outer seismic mass acts on both transducers and an additional seismic mass acts only on the inner transducer. The sensitivity of the two transducers and the inertial forces acting thereof are so selected that the two transducers, under the action of an acceleration force, each deliver equal output signals. Both seismic masses are accessible for being tuned, in their assembled condition, prior to being mounted in a housing of the accelerometer. The accelerometer requires less material, is of small volume and lightweight, and is particularly suitable for being mounted in aircraft engines. It is also easy to manufacture.

Growing community of inventors

Belfaux, Switzerland

Felix Schmid