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: A laser welding technique for joining two parts together, the parts having contacting faces which define an interfacial region. One part is permeable to a laser beam directed toward and focused on the interfacial region, the face of the other part having light-disruptive characteristics whereby when the beam impinges thereon, multiple internal reflections are produced within the interfacial region which trap the energy of the beam to generate sufficient heat to cause the parts to superficially melt and fuse.

Abstract: A differential pressure transducer of the capacitive type responsive to fluid pressure. The transducer includes a cylindrical body having insulating sections at either end provided with a planar end face and a concave cavity surrounded by an annular rim. The cavities communicate with each other through an internal duct in the body and are filled with a dielectric fluid. Covering each cavity and sealed to the surrounding rim is a diaphragm provided with a movable electrode which cooperates with a fixed electrode on the cavity surface to form a capacitor therewith whose value varies as a function of diaphragm deflection in response to an applied pressure.

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 pressure transducer of the piezoelectric type, a resonator (10) is made up of a pellet (16) mounted inside an element designed to be subjected to the action of a pressure on its exterior face (18). The pellet (16) and the element (12) are cut in the same quartz block, using a cut which provides two vibration modes. The forces resulting from the external pressure are transmitted to the edge of the pellet (16) by connecting bridges (22, 23) whose orientation is chosen so that one of the vibration modes has maximum sensitivity to the forces while the other mode has a practically zero sensitivity.