Abstract: A capacitive sensor for measuring accelerations and inclinations with respect to the gravitational field. The capacitive sensor has at least one stator electrode and one displacement electrode, in which the position of the displacement electrode can change with respect to the stator electrode, thereby resulting in a change in capacitance. From this change of capacitance, an acceleration or inclination can be measured. The capacitive sensor is distinguished by the stator electrode being designed to have an annular shape and the displacement electrode is likewise formed by an annular element which is connected to a central surface part via resilient elastic webs, and wherein the central surface part is immovably connected to the sensor housing. Alternatively, the capacitive sensor may have the stator electrode and the displacement electrode formed as polygonal shapes.

Abstract: An acceleration sensor includes an acceleration detecting element (15) for detecting an acceleration in a sealed case (11), silicon oil (16) with which the case (11) is filled for giving damping to the acceleration detecting element (15), and a deformable sealed enclosure (20) which is mounted in the case (11) and is filled with gas. A change in volume of the silicon oil (16) caused by a change in temperature of the silicon oil (16) is counteracted by the deformation of the sealed enclosure (20). The deformation of the sealed enclosure may include variations in the height and pitch of wave shapes defined by a diaphragm portion of the sealed enclosure.

Abstract: A cantilever semiconductor acceleration sensor element is supported by a pedestal fixed to a base. The base is sealed with a cap, forming an airtight space between the cap and the base that is filled with silicone oil. A central portion of the cap is deformed by an external force to increase the pressure of the silicone oil in the space to a pressure above atmospheric pressure. The generation of air bubbles on the sensor element, even at low temperature, is avoided because of the high pressure of the silicone oil.

Abstract: An accelerometer is provided which is suitably rugged for use in on-board automotive safety control and navigational systems. The preferred thick film accelerometer is formed from an alumina substrate having an integrally formed U-shaped flexure member which surrounds an intermediate support member. A mass is provided on the unsupported end of the U-shaped flexure member. Deflection is maximum at the unsupported end of the U-shaped flexure member, while strain is maximum at the supported end of the flexure member. Four piezoresistors for detecting the strain within the flexure member corresponding to the acceleration in the direction perpendicular to the plane of the support member are provided on the U-shaped flexure member adjacent its supported ends. The four piezoresistors form a Wheatstone bridge, whose analog output voltage is conditioned and amplified to provide the output signal. The signal conditioning and amplifying circuitry are preferably located on the support member.

Abstract: An acceleration pickup has a housing of a diamagnetic or paramagnetic material enclosing a ferromagnetic ball acting as seismic mass. The ball is held in a starting position on the bottom of the housing by means of a magnetic field generated by a permanent magnet or an electromagnet. By means of four induction sensitive sensors such as for example Hall effect sensors arranged opposite each other on the circumference of the housing, the momentary value and direction of acceleration component acting on the pickup is determined. The acceleration pickup is simple in construction and cost effective in manufacture and is easily adjustable to different applications.

Abstract: A device for measuring the rotational speed of a rotating object in which a tream of fluid from a back pressure sensor is directed at a chopper wheel attached to the rotating object. The output of the back pressure sensor varies as the chopper wheel rotates. The number of variations in pressure per unit time is directly proportional to the rotational speed of the rotating object.

Abstract: A damping mechanism for a two-degree-of-freedom rate gyroscope of the flexible disk type includes a pair of auxiliary disks, one mounted closely adjacent each side of the rotor disk to provide squeeze film type damping of any axial vibrations of the rotor at the resonant frequencies of the flexible rotor.

Abstract: A detector of acoustic emissions from a structure includes a piezoelectric element responsive to both compressional wave energy and to shear wave energy from any direction so that the source of the acoustic emission may be determined.

Abstract: A viscous damper for damping linear vibrations along an axis to isolate a precision instrument such as a vibrating beam accelerometer having a divided sealed cavity containing a damping fluid with a diaphragm disposed on each side of the division and a narrow gap coupling the spaces next to the two diaphragms, the diaphragms coupled respectively between an internal and an external mount with the instrument to be protected mounted to the internal mount and the external mount mounted to the body to which the instrument is attached.