Abstract: An electromagnetic accelerometer includes a peripheral frame, a mass suspended from the peripheral frame, a plurality of strain gauges configured to detect displacement of the mass, and a magnetic motor. The magnetic motor includes a first pole piece defining a chamber, a second pole piece positioned in the chamber and coupled to the mass, a permanent magnet coupled to the first pole piece, and a coil coupled to the first pole piece. The permanent magnet and the coil surround at least a portion of the second pole piece.

Abstract: An electromagnetic accelerometer includes a moving mass suspended to a peripheral frame and associated with stress gauges forming sensors for detecting the displacement of the moving mass which supports a coil, and a permanent magnet which is associated with a magnetic circuit formed by two pole pieces defining two air-gaps for channeling the magnetic field of the magnet. The moving mass includes a central recess having a surface at least equal to the surface of a free extremity of a first pole piece of the magnetic circuit and forming a shoulder for receiving the coil, the free extremity of the shoulder leading inside the air-gaps.

Abstract: A differential pressure gauge comprises a balance beam (3) acting upon a vibrating blade (6). The beam (3) and the blade (6) are disposed in a rigid chamber 4 under vacuum. The beam (3) is acted upon by a force, resulting from the deformation of a flexible or expansible chamber (7) subjected to a pressure P.sub.T and disposed in a second rigid chamber (5) subjected to a pressure P.sub.S. A flexible or expansible seal element (9) isolates the chambers but transmits the forces without disturbing them. This gauge has a high precision and delivers information in digital form, particularly useful in aeronautics.