Abstract: A pressure micro-sensor is formed by a sandwich of three silicon plates in contact by their periphery, with an interposed insulating layer in order to define an internal cavity. The lower plate (2) includes a thinner region (21) forming a diaphragm, on its internal side. The intermediate plate (1) includes a peripheral region (11) forming a frame coupled to the upper and lower plates by a silicon oxide layer (24, 25), a first stud (13) mounted onto the thinner region of the lower plate, a second stud (14) mounted onto a thick region of the lower plate, and a silicon beam (15) forming a resonator and disposed between the upper surfaces of the first and second studs in front of the upper plate (3). A first electrode (32) is connected to the upper plate, a second electrode (33) is connected to the frame and a third electrode (31) is connected to the second stud.

Abstract: A resistive strain gauge pressure sensor including upper and lower housings coacting to define a pressure chamber within the housing A board member is clamped between the housings and defines a diaphragm portion which extends across the pressure chamber to divide the pressure chamber into upper and lower chamber portions. All of the circuitry of the sensor is screen printed onto the lower planar face of the board member including the various resistor elements of the strain gauge assembly, the various elements of the conditioning circuit receiving the output of the strain gauge assembly, and the various further leads required to connect the circuitry elements to the terminals of the sensor. The sensor terminals are provided by a plurality of connector pins extending downwardly through the board member for connection at their respective lower ends to the circuitry provided on the lower face of the board member.

Abstract: A mounting assembly for a piezoelectric airblast gage includes a steel insert into which the gage is screwed. The insert is contained within a steel housing to provide a protective enclosure for the piezoelectric gage and its associated electronics. The insert is clamped inside the housing by means of a steel clamping ring which is bolted to the housing. Gaskets surround the insert on all surfaces which might come in contact with the steel housing or clamping ring. Prior to final assembly, the external electronics package for the piezoelectric gage is shock-isolated by filling the cavity beneath the insert with a shock-mitigating substance. Once fully assembly, the top of the insert and the piezoelectric gage are flush with the top of the housing.

Abstract: A sensing and displaying system is provided including a sensor unit having a transducer disposed in intimate contact with a vessel. The transducer senses a characteristic within the vessel like pressure and outputs an electrical signal representative thereof. The sensor unit further includes a response signal generator which transmits a signal representative of the characteristic. A receiver unit receives the transmitted signal and converts it to visual indicia of the characteristic, for example, a number on a liquid crystal display. The system is capable of two-way communication between the sensor unit and the receiver unit. Both the sensor unit and receiver unit store transmitted data in internal memory.

Abstract: A field emission device with an emitter on a first layer of material and an anode on a second layer of material, separated by a predetermined distance, with a sealed region therebetween. Changes in pressure external to the sealed region producing movement and consequent changes in the predetermined distance between the first and second layers, which change in distance produces a change in current between the emitter and anode. The change in current representing the change in differential pressure.

Abstract: An instrumentation system for measuring airspeed and angle-of-attack (AOA) is provided. The system includes a sensor assembly, a constant voltage anemometer, a microprocessor assembly with software, and an output device suitable for powering conventional cockpit display or for powering other speed AOA devices such as engine inlets and stability augmenters. The sensor assembly is a pair of orthogonal miniature cylinders with embedded micro-thin multielement hot film sensors. Operation of the sensor assembly by the constant voltage anemometer provides detection of cylinder leading edge flow stagnation point and oscillatory frequency. The stagnation point determination provides angle-of-attack data; the oscillatory flow frequency provides data to calculate cylinder shed-vortex frequency which is converted to airspeed data. The sensor assembly is solid-state, having no ports, diaphragms or moving parts and is heated in normal operation.

Abstract: A circuit for a pulse width modulating a sensor (12) has been provided. The circuit includes a first switch (22) for alternately coupling the sensor between first and second supply voltage terminals. The circuit also includes second (24) and third (28) switches and first and second capacitors for sampling the differential voltage appearing at outputs of the sensor when the first switch is in a closed state.

Abstract: An electrical circuit containing novel piezoresistive sensor is disclosed. The sensor is connected to a source of direct current, and a manometric pressure of at least about 15 p.s.i.g. is applied to the sensor.

Abstract: An apparatus for measuring the temperature and pressure of air in a pneumatic tire. The apparatus comprises a circuit for sensing the temperature and pressure of air in the pneumatic tire. The apparatus further comprises a circuit for transmitting a signal indicative of the temperature and pressure of air in the pneumatic tire as sensed by the circuit for sensing. The apparatus also comprises a circuit for receiving the signal from the circuit for transmitting. The signal could be used to control a vehicle suspension system.

Abstract: A device for manometric measurement of the oesophagus has a catheter with a pressure sensor and a recording unit with a light source for monochromatic and coherent light, and a counting unit for light pulses. The pressure sensor is constructed as a Fabry Perot measuring section and has a pliable optical fiber embedded in elastic base material. The optical fiber is connected via a fiber-optic light guide to the recording unit (3). One end (6) of the optical fiber (5) is metal-coated and the other end (7) is partially metal-coated and connected to the fiber-optic light guide (8). The fiber-optic light guide (8) conveys not only the light from the light source to the optical fiber but also the light pulses from the optical fiber to the counting unit.

Abstract: The formation of diaphragms by silicon wafer bonding provides for a structure having at least two such diaphragms with cavities in the wafers to which the diaphragm layer is bonded. Passageways through the wafers provide for communication of a fluid to the diaphragms. In some locations less than all of a plurality of diaphragms may be bonded to only one wafter having a cavity adjacent the diaphragm.

Abstract: Methods and apparatus for measuring gravitational and inertial forces, magnetic fields, or wave or radiant energy acting on an object or fluid in space provide an electric tunneling current through a gap between an electrode and that object or fluid in space and vary that gap with any selected one of such forces, magnetic fields, or wave or radiant energy acting on that object or fluid. These methods and apparatus sense a corresponding variation in an electric property of that gap and determine the latter force, magnetic fields, or wave or radiant energy in response to that corresponding variation, and thereby sense or measure such parameters as acceleration, position, particle mass, velocity, magnetic field strength, presence or direction, or wave or radiant energy intensity, presence or direction.

Abstract: A method for monitoring mechanical power transmission systems is disclosed, wherein the power transmission system includes at least one power transmitting element, and which is characterized for a reliable and simple measurement of elongations on the power transmitting element by the following steps: First two substantially parallel planes are established on the unstressed power transmitting element, each plane being defined by at least three space coordinates or respectively measuring points on the power transmitting element. Then, the relative change in position of the two planes to one another is determined on the stressed power transmitting element. Finally, the determined relative change in position of the planes is correlated with the local elongation or compression on the power transmitting element. An apparatus for carrying out the method is likewise described.

Abstract: A control system for controlling air pressure to a tire during the testing cycle of a tire uniformity machine includes a mechanical regulator connected to a source of air and a transducer disposed adjacent the tire and in communication with a central processing unit and the regulator to match sensed variations with predetermined testing pressure programmed into the central processing unit and activate the regulator as required.

Abstract: A semiconductor pressure sensor comprises a silicon substrate having a surface orientation of substantially (110), a diaphragm formed from the substrate, strain gauges disposed on the diaphragm, and a base joined with the substrate. The diaphragm has an octagonal shape whose sides are orthogonal to axis<100>, <110>, and<111>, respectively. This sensor causes substantially no output error and no fluctuation between output characteristics of the strain gauges irrespective of a change in temperature.

Abstract: Methods and apparatus for measuring gravitational and inertial forces, magnetic fields, or wave or radiant energy acting on an object or fluid in space provide an electric tunneling current through a gap between an electrode and that object or fluid in space and vary that gap with any selected one of such forces, magnetic fields, or wave or radiant energy acting on that object or fluid. These methods and apparatus sense a corresponding variation in an electric property of that gap and determine the latter force, magnetic fields, or wave or radiant energy in response to that corresponding variation, and thereby sense or measure such parameters as acceleration, position, particle mass, velocity, magnetic field strength, presence or direction, or wave or radiant energy intensity, presence or direction.

Abstract: A monolithic flowtube for use with an electromagnetic flowmeter includes an inner portion formed of an improved purity dielectric material having a reduced number of mobile ions, a pair of electrodes adjacent the exterior surface of the inner portion and capacitively coupled thereto, and an outer layer of ceramic material adjacent the exterior surface of the inner conduit and electrodes. A method of manufacturing the flowtube includes the steps of forming a dielectric material into a substantially tubular conduit, depositing a conductive material, preferably a refractory metal, onto the exterior of the tubular conduit, forming an outer layer of ceramic material over the tubular conduit, and firing all components simultaneously in a reducing atmosphere to form a monolithic flowtube body.

Abstract: The present invention provides a cavity examination method of a paved road which can examine cavities which are present under the paved road such as the asphalt-paved road in a reduced length of time. By collecting data of the structural conditions of areas under the paved road while traveling on the road by a pavement structure examination vehicle mounted with underground radar means, and scrutinizing according to the above results around the place which may contain a cavity by a pushcart type underground radar means, the cavity examination method of the present invention specifies presence and a planar extent of the cavity. If a cavity is actually detected, a hole with a small diameter is bored in the place and its inner circumferential wall is photographed by a camera to confirm the conditions of the cavity and the area under the pavement by a visual inspection in order to grasp the three dimensional conditions of the cavity.

Abstract: A transmitter with a flame arresting header senses a pressure of a process fluid with a diaphragm which is sealed to the header. The diaphragm transfers the pressure of the process fluid acting an outer surface of the diaphragm to a fill fluid that isolates an inner surface of the diaphragm, and a pressure sensor enclosed in the transmitter senses the pressure of the fill fluid providing an output representative of the pressure of the process fluid. The header includes a chamber on the header's outer face and a passageway extending from the chamber to a tapered opening inside the transmitter with a first portion adjacent to the tapered opening shaped to receive an inlet tube leading to the sensor and a second flame isolating portion open to the chamber. The fill fluid fills the chamber, the passageway, and the inlet tube and is sealed in with a tapered seal pressed into the tapered opening around the inlet tube.

Abstract: An apparatus for determining the length and swing weight of a golf club having a shaft and a head, the head having a sole, there being a top at the end of the shaft remote from the head comprising a longitudinally lengthwise elongated frame; first structure on the frame for supporting the club shaft to extend generally longitudinally; second structure on the frame to contact the shaft top at a first locus and to contact the head sole at a second locus, whereby the club length "1" can be measured between the first and second loci; and third structure adjustably movable relative to the frame to support the shaft at a third locus proximate the determinate center of gravity of the golf club.