Abstract: The invention disclosed herein is a pressure transducer utilizing a Hall effect sensor to detect the displacement of the transducer's diaphragm. The pressure transducer includes a power supply to draw current from a 4 mA to 20 mA current loop and deliver current to the Hall effect sensor at an average rate of 4 mA or less.

Abstract: A pressure sensor having a radially tensioned diaphragm for measuring fluid pressure. The pressure sensor includes a first generally concave metal body member and a second generally concave metal body member, and a radially tensioned flexible metal diaphragm disposed therebetween that is tensioned by heating the sensor. The first and second body members are formed from a material having a coefficient of thermal expansion in the range of approximately 0.0000056 inch/inch/° F. to 0.0000064 inch/inch/° F. The diaphragm is formed from a precipitation hardening metal material having a coefficient of thermal expansion of approximately 0.0000060 inch/inch/° F. The first body member and the second body member are formed from a ferromagnetic metal material such that the first and second body members shield the diaphragm from magnetic fields which may otherwise cause movement of the diaphragm.

Abstract: A pressure gage adapted to provide a mechanical indication of a sensed pressure and to provide an electrical signal indicative of the sensed pressure. The pressure gage includes a housing having a first fluid pressure chamber, a second fluid pressure chamber, and flexible diaphragm separating the first fluid pressure chamber from the second fluid pressure chamber. A magnet is coupled to the diaphragm such that movement of the diaphragm causes a related movement of the magnet. A helix is located adjacent to the magnet and a pointer is attached to the helix for conjoint rotation with a helix about a rotational axis. A Hall effect sensor is also located adjacent the magnet. Movement of the magnet in response to movement of the diaphragm rotates the helix and the pointer to provide a mechanical indication of the pressure sensed by the diaphragm, and the movement of the magnet causes the Hall effect sensor to generate an electrical signal indicative of the pressure sensed by the diaphragm.

Abstract: A thermal anemometer that separates sensor heating from sensor temperature measurement through a switched sampling technique. This approach demonstrates several advantages over the more typical circuitry employing a bridge, which simultaneously heats the sensor and senses the ambient and velocity sensor temperature. In a thermal anemometer in accordance with the present invention, sensor temperature is determined by sampled measurement of its resistance. Sensor temperature is controlled by varying the voltage applied to the sensor with an error value determined by the difference between actual sensor resistance and the desired resistance.

Abstract: A pressure sensor having a radially tensioned diaphragm for measuring fluid pressure. The pressure sensor includes a first generally concave metal body member and a second generally concave metal body member, and a radially tensioned flexible metal diaphragm located therebetween that is tensioned by heating the sensor. The first and second body members are formed from a material having a coefficient of thermal expansion in the range of approximately 0.0000056 inch/inch/° F. to 0.0000064 inch/inch/° F. The diaphragm is formed from a precipitation hardening metal material having a coefficient of thermal expansion of approximately 0.0000060 inch/inch/° F. The first body member and the second body member are formed from a ferromagnetic metal material such that the first and second body members shield the diaphragm from magnetic fields which may otherwise cause movement of the diaphragm.

Abstract: A flowmeter for sensing fluid flow. The flowmeter includes a housing including a first port, a second port, a chamber in fluid communication with the first port and the second port, and a fluid passageway extending from the first port to the second port. An impeller having a non-magnetized metal pole piece is located within the chamber of the housing and is rotatable about an axis in response to fluid flow through the fluid passageway. A Hall Effect sensor and a magnet are located outside of the fluid passageway. The magnetic field generated by the magnet enables the Hall Effect sensor to sense rotation of the impeller and thereby the rate of fluid flow through the fluid passageway.

Abstract: A flowmeter for measuring fluid flow including a body having a receptacle including a cavity formed by a threadless cylindrical side wall, a stopper adapted to be inserted into the cavity of the receptacle including a generally cylindrical threadless shank having an annular groove, and a clip member slidably located in a passage of the body. The clip member is slidable between a first position wherein the clip member is located within the annular groove of the stopper to prevent removal of the stopper from the body, and a second position wherein the clip member is located outside of the annular groove of the stopper whereby the stopper may be longitudinally removed from the receptacle of the body.

Abstract: A manometer for measuring fluid pressure having a first pressure sensor and a second pressure sensor that is inverted with respect to the first pressure sensor. The first pressure sensor generates a first electrical output signal corresponding to a fluid pressure measured by a first diaphragm of the first pressure sensor. The second pressure sensor generates a second electrical output signal corresponding to a fluid pressure measured by a second diaphragm of the second pressure sensor. The first and second electrical output signals are combined into a combined electrical output signal. False readings of a change in/pressure measured by the first pressure sensor and measured by the second pressure sensor in each of the first and second electrical output signals, due to movement of the manometer, are cancelled by one another in the combined electrical output signal to provide an accurate pressure measurement regardless of movement of the manometer.

Abstract: A differential pressure switch comprising an enclosure including a peripheral wall and a solid one-piece non-perforate partition wall that is integrally attached to the peripheral wall around the entire perimeter of the partition wall. The enclosure includes a sensor chamber located on a first side of the partition wall and a fluid cavity located on a second side of the partition wall. The partition wall and the integrally attached peripheral wall seal the sensor chamber in fluid-tight leak-proof isolation from the fluid cavity. A flexible diaphragm is located within the fluid cavity and forms a low-pressure fluid chamber on one side and a high-pressure fluid chamber on a second side of the diaphragm. A magnet is located in the fluid cavity and is coupled to the diaphragm such that the magnet changes position in response to movement of the diaphragm. A Hall effect sensor is located in the sensor chamber.

Abstract: An all molded flowmeter assembly that is especially adapted for use in connection with medical and laboratory type equipment applications for measuring and/or controlling fluid flow and is arranged for snap-fit mounting at its ends with respect to the flow monitoring panel normally provided such equipment, wherein the assembly is in the form of a basic flowmeter body and a selection of upper and lower end caps therefor that serve the usual intake and output functioning needed for devices of this type, including as options, where the application requires a metering system, end caps equipped with metering devices for pressure and vacuum applications; the general arrangement involved is such that the resulting flowmeter assembly provided by the basic flowmeter body and user selected end caps therefor may be readily assembled, and the resulting "whole" snap-fit mounted on such usual panel after suitably sized mounting aperturing is formed in such panel, and further, the general arrangement involved does not requi

Abstract: A rotary position indicator for use with devices such as valves, electrical switches, and non-contact reed and proximity switches, which rotary position indicator includes a shaft rotatable about its longitudinal axis and includes a single plane adjustable cam bearing an external profile at its margin that is shaped to provide a camming portion for predetermined dwell and a camming portion for actuator of the device controlled thereby, which provides the option of adjusting the position of the cam relative to the shaft by the user manually shifting the cam in its plane to effect release of the cam relative to the shaft for rotation relative to the shaft to its new working position, with automatic releasable locking of said cam in its new working position then being effected.

Abstract: A hermetically sealed snap switch assembly involving a housing that includes a hermetically sealed snap switch chamber in which a projecting terminal type subminiature snap action switch is mounted in slip fit association with a similar number of depending electrically conductive open ended tubes that are adapted to, prior to use of the switch assembly involved, be respectively hermetically sealed to the switch terminal that is received in same, and be respectively electrically connected in suitable circuitry at the option of the installer, with the arrangement of the assembly being such that optionally a selected one of the depending tubes, prior to such hermetically sealing of same, may be employed for switch chamber purging and backfilling purposes, after which said sealing of same is effected. Also disclosed is a method of backfilling said switch chamber (using such backfilling option) with a switch life enhancing gas.

Abstract: A basic housing for a fluid flow monitoring assembly comprising a sensing leakproof elongate hollow body formed from a non-magnetic, metallic material and pivotally mounting internally of same a vane assembly that at one end includes a vane adapted to be inserted into a fluid flow of piping, with the vane assembly being spring biased to pivot oppositely of the direction of fluid flow, about its pivot mounting, for zero or reduced fluid flow conditions, and at its other end including a permanent magnet for electrically actuating a switch mechanism; such elongate sensing body defines an open end through which the vane projects and closed a end adjacent the magnet, which elongate body adjustably mounts crosswise thereof at its closed end within the permeability of the magnet for set point adjustment purposes a novel flow switch assembly comprising a plastic housing that is also leakproof and potably mounts in hermetically sealed relation a commercially available reed type off-on switch in electrical circuit arra

Abstract: A self cleaning device for rotatable sight glass equipped visual flow indicators (for visually indicating fluid flow therethrough) that includes several stationary wiper implements that each include a wiper holder fixedly mounting a wiper in the form of a tube of compressible material that is in compressed wiping engagement with the inside surfacing of the sight glass, for improved wiping away of foreign materials when the sight glass is rotated for this purpose.

Abstract: A shoe tester for use in environments where static electricity sparking must be eliminated between so called Electrostatic Dissipating (ESD) shoes and the floor, by personnel wearing a pair of such shoes, wherein the tester comprises a pair of metallic electrically conductive shoe plates secured together in spaced but side-by-side relation resting on such floor on insulated studs or the like, on which the person wearing the shoe stands with his shoes on the respective plates, and a "plug-in" electronic circuit for measuring the resistance of such person and the shoes, including a scale and a pointer arm associated with the tester for actuation by the circuit when electrically energized by any grounded 115 volt alternating current outlet available for indicating acceptable and unacceptable shoe resistances, wherein the circuit includes an amplifier arrangement that permits the resistance measurements to be made to be in the range of 2,000 megohms.

Abstract: A differential pressure switch assembly for low pressure applications permitting accurate "in field" set pointing of same, comprising a capsulized instrument that includes housing high and low pressure sections defining in assembled relation a pressure cavity across which such sections mount a flexible diaphragm separating high and low pressure chambers, with the low pressure section mounting at a site on the low pressure section a snap switch unit of a size appropriate for such assembly, which unit has a projecting plunger therefor that has an end portion disposed in the low pressure chamber of the unit, with the assembly further comprising a pressure differential sensor disposed for effecting electrical switching of the snap switch unit when the pressure of the assembly high pressure chamber exceeds that of the low pressure chamber by a predetermined differential.