Vibro-meter Sa

Meggitt Sa

Jacques Perriard

Felix Schmid

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 invention pertains to an eddy current sensor with a sensor circuit having a head portion, including a sensor coil, a base portion and a transmission cable connecting the head portion to the base portion. The transmission cable is a triaxial cable and the sensor coil is connected between the inner conductor and the outer shield of this cable. The base portion of the sensor circuit comprises a voltage follower connected to buffer the voltage of the center conductor and apply it to the inner shield of the triaxial cable in order to isolate the cable's line capacitance from the sensor coil. The invention further concerns a sensor coil for an eddy current sensor, having a segmented winding structure with a particularly low self-capacitance. In a preferred embodiment, the triaxial transmission cable is combined with a sensor coil having this segmented winding structure.

Eddy current sensor and sensor coil for the same

An electronic circuit serving as an interface between a piezoelectric transducer and a circuit for processing a measuring signal provided by said transducer, said electronic interface circuit serving for providing a constant direct current to said piezoelectric transducer, and for pre-processing an electric signal provided by the transducer via a voltage modulator, said electronic interface circuit being connected to said voltage modulator by a cable having two terminals at each end, the two terminals at a first end of the cable being connected to the output of the voltage modulator and the two terminals at a second end of the cable being connected to said electronic interface circuit. In order to eliminate the error signals caused in particular by common mode interference voltages ('frame voltage'), said electronic interface circuit is characterized in that it comprises (a) a first direct current source for providing a first constant current to said transducer through an electric current loop; (b) a second direct current source for absorbing a second constant current returning from said transducer to said electronic circuit through said loop while said transducer is supplied with said first current; (c) one or a plurality of passive elements allowing to absorb the difference between said first constant current and said second constant current.

Growing community of inventors

Romont, Switzerland

Jacques Perriard