Abstract: A supporting device including four independent and identical U-shaped coupling flanges each cooperating with a pair of springs. Each spring is formed of a circular cross section metal wire made of high elastic limit alloy. The set of coupling flanges and springs is symmetrical with respect to two mutually perpendicular axial planes of resonator and with respect to a central plane of the resonator. A cylindrical element is mounted inside the casing in a region of a lateral wall of the housing and has a circular groove on its inner face and located on a center plane parallel to the top and bottom walls of the housing. For each pair of springs cooperating with a coupling flange, one of the springs engages by a first portion into an upper slot formed in a planar rear face of the coupling flange and by a second portion in the circular groove. The inner faces of the coupling flanges rest directly on the edge of the top and bottom faces of the resonator.

Abstract: Device for supporting a piezoelectric resonator inside a casing. The device comprises two cross-shaped half-shells, each one comprising: four branches of which the free ends define angle pieces with a horizontal bearing surface of small dimension, which surface is slightly raised with respect to the central part of the corresponding half-shell, as well as one vertical branch holding the edge of the resonator: four identical independent securing flanges to secure the two half-shells in position, said flanges having the shape of a turned down U, each flange comprising, at the end of each branch of the U, two stop elements bearing against two superposed branches of the two half-shells, on the faces of those branches facing said horizontal bearing surfaces; and at least four pairs of springs for suspending the four securing flanges with respect to the casing.

Abstract: In a piezoelectric transducer (10) an external element (12) of tubular form receives a pressure, notably a pressure to be measured, on its external face (16). It is cut in a quartz crystal in one piece with a plate (25) capable of vibrating under the action of an electric stress and extending in a plane parallel to the longitudinal direction of the tubular element inside the latter. Each of the longitudinal edges of the plate is connected by a transverse connecting element (30, 31) to the internal face (14) of the tubular element so as to transmit forces (F1 and F2) resulting from the application of the external pressure to the plate (25) in a direction substantially parallel to its plane and perpendicular to the axis of the tubular element (12).

Abstract: A piezoelectric bi-resonator with electrodes not adhering to the crystal, comprising at least first and second plates in dielectric material on which plates are deposited respectively first and second electrodes, a third plate in dielectric material having faces opposed to the first and second plates respectively, on which faces are respectively deposited third and fourth electrodes, connected together, and a piezoelectric body constituted by two piezoelectric chips made of quartz, independent and similar, one of which is interposed between the said first and third electrodes, without contact therewith, and the other is interposed between the second and fourth electrodes without contact therewith, the said piezoelectric quartz chips being arranged so that their axes Y' are opposite.