Abstract: The present invention provides piezoelectric surface mount devices in which the area of the mounting terminals is reduced, leading to reduction of manufacturing cost. A piezoelectric device comprises a package base (120) including a bottom surface having a long edge and a short edge and a pair of mounting terminals formed on respective short edges of the package base. The pair of mounting terminals are separated by a predetermined longitudinal distance (X3) and are arranged as close as possible to the longitudinal center line of the package base. The predetermined distance is sufficient to prevent electrical short when mounting the piezoelectric device onto the printed substrate. The maximum width (Z2) of each mounting terminal measured in a direction parallel with the short edges of the package base is less than one half the width of the short edge (Z1).

Abstract: An exemplary piezoelectric device has a piezoelectric vibrating board including a portion that exhibits thickness-shear vibration, and a frame portion extending around and supporting the vibrating portion. A first cover board, bonded to the first main surface of the frame portion, has a first excitation electrode. A second cover board, bonded to the second main surface of the frame portion, has a second excitation electrode. Thus, the vibrating portion is sealed in a package formed by the frame portion and cover boards. A first convexity, defined either on the bonded main surface of the first cover board or on the first main surface of the frame portion, surrounds the excitation electrode and establishes a predetermined gap between the vibrating portion and excitation electrode. The first cover board and frame portion are bonded by adhesive applied, adjacent the first convexity but not on the first convexity, continuously around the vibrating portion.

Abstract: A thin film resonator comprising a piezoelectric material and having a controllable or tunable resonant frequency. The resonator is formed on a substrate having a cavity formed therein below the piezoelectric film material. A bending electrode is disposed within the cavity and the application of a voltage between the bending electrode and one of the resonator electrodes, creates an electric field that causes the substrate region to bend. These stresses caused: by the bending are transferred to the thin film resonator, subjecting the piezoelectric film to stresses and thereby changing the resonant properties of the thin film resonator.

Abstract: The variable air-gap type driving detector of the present invention for obtaining low speed and high torque outputs required to drive, for example, joints of industrial robots is provided with an elastic supporting means 22, whose one end is supported on a base stand 21 , for supporting a rotor 5 so as to restrain the rotor 5's autorotation; and an eccentric supporting meals, whose rotation shaft 23b is supported on the base stand 21 in a freely rotatable state, and an outside of whose eccentric shaft 23a is supported inside the motor 5, and further whose rotation shaft 23b rotates with the revolution of the rotor 5; and the driving device of the invention becomes simple in structure and small in size by being composed of using no cranks or only a crank.

Abstract: A circuit interruption device having a plurality of micromechanical switches mounted on a substrate in a parallel-series array. The array includes a plurality of line branches connected in parallel in a circuit line. Each of the line branches has at least two of the switches serially connected therein. The micromechanical switches each has a pair of contacts formed on the substrate, a bridging contact movably formed on the substrate, and an actuator for causing the bridging contact to move in and out of contact with the contacts. The bridging contact can be either a member slidably disposed in a channel formed on the substrate or member attached to an end of a cantilever having its other end attached to the substrate. The actuator is controlled by a trip device which is also mounted on the substrate. The trip device senses the current in the circuit line and causes the switches to open when a predetermined level of current in the line is exceeded.

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.

Abstract: A quartz resonator drawer is housed in a monolithic block cabinet made of quartz. Air gap electrodes are provided on interior walls of the cabinet. The resonator drawer can be removed from the cabinet without dissemblying the electrodes or the cabinet.

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.