Abstract: Electrostatic capacitance measurements are used to detect chemical or biological analytes, or chemical interactions, with great sensitivity. A diaphragm is coated with a material capable of selectively interacting with an analyte of interest, and interaction of the analyte with the coating exerts stresses tangential to the diaphragm's surface. These stresses cause diaphragm displacements that are sensed as varying capacitance.

Abstract: The flow meter probe with force sensors has the body of a frustum of a regular pyramid with a force sensor disposed upon each face. The force sensors are mounted in bores defined in the probe body and include a pin that may be displaced in the bore to exert pressure on an electrical transducer. The transducer may be a ceramic, piezoelectric sensor or a Micro-Electro-Mechanical System (MEMS) sensor. The pin has an aerodynamically- or hydrodynamically-shaped head, a cylindrical body, and a frustoconical tail to concentrate force exerted upon the sensor. The head of the pin protrudes slightly above the face of the probe body so that aerodynamic and hydrodynamic forces are exerted directly against the pin, and pin displacement measures the forces directly. A plurality of probes may be placed in the path of fluid flow in a variety of configurations, as desired.

Abstract: A dispensing system for feeding paste through a screen onto a workpiece monitors the position of a piston applying pressure to the paste with a linear variable differential transformer and sets limits on the slope of the piston displacement is a measure of the feed rate and the “spring back” of the piston when pressure is released, as a measure of trapped air in the system.

Abstract: A micromechanical structural element, having a very stable diaphragm, implemented in a pure front process and in a layer construction on a substrate. The layer construction includes at least one sacrificial layer and one diaphragm layer above the sacrificial layer, which is structured for laying bare the diaphragm and generating stabilizing elements on the diaphragm, at least one recess being generated for a stabilizing element of the diaphragm. The structure generated in the sacrificial layer is then at least superficially closed with at least one material layer being deposited above the structured sacrificial layer, this material layer forming at least a part of the diaphragm layer and being structured to generate at least one etch hole for etching the sacrificial layer, which is removed from the region under the etch hole, the diaphragm and the at least one stabilizing element being laid bare, a cavity being created under the diaphragm.

Abstract: Fuel gauges for fuel supplies for fuel cells are disclosed. Each fuel gauge has a property that is readable by an electrical circuit. These properties are related to the remaining fuel in the fuel supplies. These properties include, but are not limited to, electrical capacitance, magnetic, semi-conducting resistance, bi-metal resistance, and oscillating magnetic field. These fuel gauges are functional at any fuel supply orientation.

Abstract: A fluid volume measuring apparatus for measuring volume of fluid flowing out of a measured object includes a passage member that defines a measurement passage. The measurement passage is filled with fluid, which is capable of moving in the measurement passage in accordance with volume of fluid flowing out of the measured object. The fluid filled in the measurement passage forms a bubble. The passage member has a translucent portion in a predetermined measurement range, in which the bubble displaces in accordance with volume of fluid flowing out of the object to be measured. The translucent portion is formed of a translucent material. Volume of fluid, which flows out of the measured object, is measured in accordance with displacement of the bubble.

Abstract: An apparatus for measuring pressure includes a cylindrical tube having an open end and a closed end; a piston disposed in the cylindrical tube at the open end; an accelerometer attached to a side of the piston that faces the closed end of the tube, the accelerometer for measuring the acceleration of the piston after a blast event; and a pressure sensor located inside the tube for measuring pressure in the tube between the piston and the closed end of the tube. The apparatus also includes a data processor and computer connected by wires to the accelerometer and pressure sensor for receiving signals generated by the accelerometer and pressure sensor.

Abstract: A multiple mode pre-loadable fiber optic pressure and temperature sensor includes a generally cylindrical structure having at least one compression element, a fiber optic having a Bragg grating in contact with one side of the compression element, a diaphragm in contact with the other side of the compression element, and a fluid port in fluid communication with the diaphragm. According to preferred aspects of the, a groove is provided in at least one compression element for receiving the fiber optic. The sensor is pre-loaded by straining the diaphragm over the adjacent compression element when the cover is attached. The compression element in contact with the diaphragm preferably has a contoured surface contacting the diaphragm and the diaphragm is stretched to match that contour. By varying the contour of the compression element and the thickness of the diaphragm, the dynamic range of the sensor can be changed. The preferred diaphragm has a variable thickness and is made as an integral part of the structure.

Abstract: A method and device for use with a hydraulic system is adapted to measure a position, velocity and/or acceleration of a piston of a hydraulic actuator based upon differential pressure measurement. The device of the present invention utilizes a differential pressure flow sensor to establish a flow rate of a hydraulic fluid flow traveling into and out of a cavity of the hydraulic actuator, from which the position, velocity and acceleration of the piston can be determined.

Abstract: A transducer for measuring the relative velocity of movement of a body in a liquid or gaseous medium employs no reciprocating parts and functions by sensing the force applied to a diaphragm (6) die to its movement through the medium or the movement of the medium towards the diaphragm. The speed transducer makes use of a Hall effect solid state device (7) that produces an output when a magnetic field is applied to either of its surfaces. The level of the output voltage is proportional to the velocity of movement in the positive direction, i.e. when the force acts on diaphragm (6) in (FIG. 1). Since the transducer takes into account differential forces, an unwanted common force acting on both diaphragms simultaneously will have no effect on the measured speed. The tubular body (1) in which the Hall effect device is located may be made from any non-magnetic material suitable for the environment in which the transducer will be used.

Abstract: A flow sensor is provided with an obstruction (8) projecting into a flow and at least one measuring probe (10) for measuring a vortex produced by the obstruction (8). The measuring probe (10) includes at least one membrane (12) and a measuring element arranged directly on the membrane (12), for detecting the membrane deflection.

Abstract: In a method and apparatus for measuring pressure, sound and vibration, particularly for the flow analysis on missiles or airplanes, a sensor device which is used to sense pressure or sound waves, is linked to a structure of a structural part in order to measure forces acting upon the structural part surface. The sensor device is arranged completely inside the structure of the structural part or on the rear side of the structural part surface. In particular, the sensor device may comprise a piezoelectric foil which is situated under the structural part surface.

Abstract: To detect a low load of an outrigger with high accuracy and improve alarming accuracy of a roll-over alarming device, the roll-over alarming device for a crane includes a load cell 1 having a coil spring 5 provided with a strain gauge 4, and an upper load cell case 6 and a lower load cell case 7 which support the coil spring 5 from its top and bottom to transfer a load of an outrigger to the coil spring 5, supports 8, 9 for supporting a load when the load having more than a predetermined value acts to restrain yielding of the coil spring 5 being provided between the upper load cell case 6 and the lower load cell case 7, and an alarming section which issues a roll-over alarm on the basis of a load detecting value of the outrigger from the load cell 1.

Abstract: A flow rate sensor high in pressure resistance has a structure to facilitate the measurement of a minuscule differential pressure for measurement of a very small flow rate. A chamber (20) is defined into a primary chamber (21) and a secondary chamber (25) by two diaphragms (31, 32) arranged in an opposed relation to each other. A fluid is passed from the primary chamber to the secondary chamber through a bypass (35) having an orifice portion (40) thereby to generate a differential pressure. The load generated by the fluid pressure fluctuations received by the first and second diaphragms is detected as a difference of displacement by a load difference sensor (50) arranged between the first and second diaphragms thereby to detect the flow rate of the fluid. Displacement limiting members (61, 62) are provided for the diaphragms or the load difference sensor so that the displacement due to the fluid pressure fluctuations received by the first and second diaphragms may not exceed a predetermined amount.

Abstract: A differential pressure transmitter for sensing a physical variable related to a process fluid of an industrial system, comprising:

Abstract: Apparatus for determining fluid flow through a pressure regulator is disclosed. The pressure regulator is disposed in a fluid flow passage and has a throttling element moveable in the flow passage. A stem is attached to the throttling element. The apparatus includes a first pressure sensor for measuring pressure upstream of the throttling element, a second pressure sensor for measuring pressure downstream of the throttling element, and a travel sensor for detecting the position of the throttling element. A processor is provided which includes a stored algorithm for determining flow rate based on the measured pressure and travel values.

Abstract: In a method of producing a micromechanical structure for a micro-electromechanical element, a first intermediate layer, which is applied to a first main surface of a first semiconductor wafer, is structured in a first step so as to produce a recess. The first semiconductor wafer is then connected via the first intermediate layer to a second semiconductor wafer in such a way that a hermetically sealed cavity is defined by the recess. Finally, one of the wafers is thinned from a surface facing away from said first intermediate layer so as to produce a diaphragm-like structure on top of the cavity. At least one further intermediate layer is provided between the two semiconductor wavers which, prior to the connection of the two semiconductor wafers, is structured in such a way that the structure formed in said at least one further intermediate layer and the recess in said first intermediate layer define the cavity.

Abstract: Piezoelectric transducer assemblies that are useful for the monitoring of the gas output from a gas driven pump, wherein the assembly is not an integral part of the input or output flow stream of the material being pumped, but is used to monitor the exhaust gas flow of the gas driven pump.

Abstract: The present invention pertains to a pressure sensor for measuring absolute dynamic pressure. The sensor comprises a frame surrounding a diaphragm, wherein the diaphragm is spaced from the frame by at least two slits which define a restriction that places a reference chamber in fluid communication with a surrounding environment. The diaphragm is connected to the frame at two transition areas, which transition areas are separated from one another by the slits.

Abstract: The present invention relates to a pressure transducer assembly (1; 24; 39) on a process circuit (2; 29, 30; 48, 49) as is used in a process plant, whereby the process circuit (2; 29, 30; 48, 49) is capable of carrying a hot fluid. Furthermore at least one fluid carrying measuring line (5; 26, 27; 40, 41) is provided between the process circuit (2; 29, 30; 48, 49) and a valve (4) of the pressure transducer (3; 25; 42), and/or transducer. Furthermore first and second flange connections (6, 10; 31, 32; 44) are provided between connections on the process line 9)2; 29; 30) and the fluid measuring line (5; 26, 27; 40, 41) as well as between the valve (4) and the fluid measuring line (5; 26, 27; 40, 41). These flange connections are connected to each other by means of nuts and bolts (9, 13; 38).

Abstract: A monitoring system (10) is disclosed for monitoring the condition of a filter (16) filtering a gas or liquid. Using various sensors, the permeability of the filter is monitored on a continuous basis. A significant increase in permeability, decrease in permeability or rate of change of permeability can lead to an indication of filter failure, such as rupture, leakage, loading and unloading. The system can be monitored by a computer and monitored from a remote location through phone lines and Internet computer systems.

Abstract: Structures and methods are disclosed in conjunction with the fabrication of electrical lead transfer feedthroughs with respect to a sealed cavity. In some applications such as capacitive pressure sensing, the cavity may include an outer wall, in which case the electrically insulating barrier is preferably U-shaped, with the ends of the U terminating at the outer wall. The feedthrough section may alternatively take the form of an island of conductive material surrounded by the electrically insulating barrier, thus assuming an O-shape. The cavity may be evacuated or filled with specific gases at specific pressures. As such, the invention finds application in the packaging (vacuum or controlled environment) and production of a variety of transducers including but not limited to pressure sensors, flow sensors, optical devices (e.g., infrared detectors, ccd camera, and flat-panel displays) and resonating devices, such as gyroscopes, accelerometers, yaw sensors, telecommunication devices, etc.

Abstract: An apparatus for delivering fluids at a precisely controlled rate which includes a fluid dispensing component having a fluid reservoir for containing the fluids to be delivered and a reservoir fill component which can be removably interconnected with the fluid dispensing component. The reservoir fill assembly is uniquely designed to accept a vial component of conventional construction which is factory filled with the medicinal fluid to be delivered to the patient. The dispenser component embodies a highly novel fluid flow indicator that provides a readily discernible visual indication of fluid flow status through the device.

Abstract: A micromechanically produced flow-restriction device has a first passage opening formed in a first main surface of a substrate. A channel is formed in a second main surface of the substrate and one end thereof is in fluid communication with the first passage opening. A second passage opening is in fluid communication with a second end of the channel. The first passage opening, the channel and the second passage opening define a flow path. A membrane is formed in the substrate and is in fluid communication with the first passage opening. A membrane electrode is formed at least on the membrane.

Abstract: A proportioning element (10) for proportioning a fluid flow from an input side to an output side of the proportioning element (10) comprises a membrane (12) provided with at least one opening (16) acting as a flow resistor for a medium to be proportioned. The membrane (12) has additionally integrated therein a pressure sensor (14) used for detecting a pressure difference between the input side and the output side of the proportioning element (10). The proportioning element is implemented as a semiconductor chip, the membrane (12) being a semiconductor membrane and areas of the semiconductor chip which are exposed to the medium to be proportioned being provided with a passivation layer.