Abstract: A variable-area flowmeter system adapted to produce a pneumatic output indication that is linearly proportional to flow rate. The primary of the system includes a float contained in a variable area tube through which flows the fluid to be metered, the float being raised or lowered in the tube as a function of flow rate. A bar magnet is physically coupled to the float and moves axially therewith. The secondary of the system includes a rotatable follower magnet magnetically coupled to the bar magnet to convert the axial movement into rotary motion and an edge-profiled input disc mounted on the shaft of the follower magnet whereby the disc rotates in a direction and to an extent depending on flow rate. The profile is designed to afford a linear relationship between input rotation and output pressure.

Abstract: A vortex flowmeter for installation in water or other lines to be tested on occasion. The flowmeter includes a flow tube forming a passage for the fluid to be metered and an obstacle assembly mounted therein and capable of generating fluidic oscillations causing a deflectable section of the assembly to vibrate at a corresponding frequency proportional to flow rate. The vibrations of the deflectable section are transmitted to a coupling point outside of the flow tube, whereby the flow rate in any installed flowmeter may be read by an external sensor engaging the coupling point to produce a signal which is fed to a digital indicator, the same system being used to read all of the flowmeters. In order to correct for disparities in the meter factors of the various flowmeters, each meter is provided with an impedance element whose value is determined by the degree of correction required.

Abstract: A liquid level transmitter in which the level of liquid in a tank is detected by a sensor formed by a housing attached to the tank over an opening therein, the housing having a fill chamber defined by a sensing diaphragm which is exposed to the liquid in the tank and an insert incorporated within the housing and spaced from the diaphragm. The sensor housing is joined by a support tube to the body of a force balance meter which includes a pivoted force beam whose lower extermity is mechanically linked to a force measuring diaphragm disposed in a diaphragm chamber. The fill chamber of the sensor communicates with the diaphragm chamber of the meter by way of a capillary extended through the coupling tube. The fill chamber, the capillary and the diaphragm chamber contain hydraulic fluid, whereby tank liquid pressure imposed on the sensing diaphragm is transferred hydraulically to the force measuring diaphragm to deflect the force beam.

Abstract: An electromagnetic flowmeter capable of measuring fluids having any degree of conductivity, including fluids having dielectric properties. The fluid to be measured is fed through a dielectrically-lined flow tube to intersect a transverse magnetic field, thereby inducing a voltage in a pair of planar detecting electrodes disposed within the dielectric lining. Each detecting electrode and an associated planar shielding electrode are unitized in an assembly wherein the electrodes are embedded in a liner segment formed of rigid dielectric material, connections to the electrodes being made by means of a coaxial line extending radially through an opening in the flow tube, the line having an outer conductor attached to the shielding electrode and an inner conductor attached to the detector electrode, the space between the line conductors being filled with the same dielectric material as that of the segment.

Abstract: A displacement transducer capable of accurately measuring small displacements. The transducer includes a magnetostrictive wire exposed to a stationary magnetic field and having an S-shape, one arc forming one section of the wire and the reverse arc the adjacent section. One end of the wire is fixed, whereas the other end is attached to a displaceable element whereby movement of the element changes the radius of curvature of the arcs. An amplifier whose input is connected to one section of the wire and whose output is connected to the other section thereof yields electrical pulses in the output to produce torsional vibration of the two sections, creating a sinusoidal electrical signal which is fed back to the amplifier input, thereby sustaining oscillations therein whose frequency depends on the radius of curvature and is therefore a function of the extent of displacement. Means are provided to linearize the relationship between displacement and frequency.

Abstract: A two-wire transmission system for a vortex-type flowmeter whose sensor generates a low-level a-c signal having a frequency that depends on flow rate, the signal being fed to the input of a pre-amplifier adjacent the meter. The two-wire system serves to supply d-c power to the pre-amplifier from a remote d-c source and to conduct the a-c output of the pre-amplifier to a remote output point. The system includes a DC-to-DC converter constituted by a high-frequency oscillator whose circuit incorporates the primary of an isolation transformer, the secondary of which is coupled to a rectifier supplying d-c to the power terminals of the pre-amplifier. Connected across the pre-amplifier output is a load resistor which draws a sufficiently heavy current to modulate the d-c power consumed by the pre-amplifier in accordance with the amplified a-c signal.

Abstract: A system for measuring the mass flow of a fluid stream wherein gas is interspersed with liquid, the system providing separate mass flow readings for the gas and liquid. The system includes a mass flow vortex-type meter having a flow tube through which the stream is conducted, the meter producing an output signal whose frequency is indicative of volumetric flow and whose amplitude is indicative of mass flow. This output signal is routed either to a liquid-mass flow indicator or to a gas-mass flow indicator by a switch responsive to a density signal whose magnitude depends on the density of the fluid passing through the meter, such that when the stream is in liquid form the output signal is applied to the liquid indicator, and when in gas form to the gas indicator.

Abstract: A non-contact sensor for a vortex-type flowmeter in which the fluid to be measured is conducted through a flow tube having an obstacle assembly mounted therein capable of generating fluidic oscillations causing a deflectable section of the assembly to vibrate at a corresponding rate. These vibrations are sensed to produce an output signal whose frequency is proportional to the flow rate of the fluid, the sensor being constituted by a magnetically-dependent member which is subjected to a changing magnetic field by a proximity element attached to the deflectable section and vibrating therewith to induce in the member electrical changes producing said output signal.

Abstract: An adapter for a vortex-shedding flowmeter serving to render the meter capable of measuring low flow rates below its normal operating range. The flowmeter includes a flow tube forming a passage for the fluid to be measured and an obstacle assembly mounted therein for generating fluidic oscillations which frequency is proportional to flow rate. The adapter includes means that act to restrict the effective area of the fluid traversing the obstacle assembly, whereby for the same velocity of flow past the assembly a smaller amount of fluid is metered. By providing a set of adapters introducing different areas of restriction, the meter is then able to function as a multi-range instrument.

Abstract: An acceleration-proof vortex type flowmeter in which the fluid to be measured is conducted through a flow tube having an obstacle assembly mounted therein capable of generating periodic vortices causing a deflectable section of the assembly to swing at a corresponding rate. The swing is sensed to produce an output signal whose frequency is proportional to the flow rate of the fluid. The deflectable section is cantilevered from a fixed section by upper and lower beams, the mass of the deflectable section being balanced with respect to the lower beam which acts as a torsion rod. The physical characteristics of the beams are such as to render the obstacle assembly substantially insensitive to acceleration forces.

Abstract: An electromagnetic flowmeter system capable of measuring fluids having any degree of conductivity, including fluids having dielectric properties. The fluid to be measured is conducted through a dielectrically-lined flow tube to intersect a transverse magnetic field produced by an electromagnet, thereby inducing a voltage in a pair of planar electrodes mounted within the dielectric lining, each electrode being provided with a driven shield. The electromagnet is excited by a direct voltage which is periodically interrupted to produce a periodic steady state field whereby unwanted in-phase and quadrature components are minimized.

Abstract: A differential-pressure transmitter adapted to produce a signal proportional to a process variable such as flow rate in a line conducting fluid or the level of liquid in a tank, the process fluid being at a temperature markedly at variance with ambient temperature. The transmitter is constituted by high and low pressure sensors which are coupled to the force beam of a force balance transducer so that the beam is responsive to the difference between sensed high and low pressures derived from the process variable, the transducer being exposed to ambient temperature. Each sensor is constituted by a housing having a well therein covered by a sensing diaphragm and an insert seated in the well, the face of the insert being spaced from the diaphragm to define a fill chamber containing hydraulic fluid, the sensor diaphragm being exposed to the process liquid, whereby heat transfer takes place between the liquid and the hydraulic fluid.

Abstract: An electromagnetic flowmeter having a flow tube which is interposable in a normally less-than-full fluid line. A pair of arcuate electrodes are mounted in the flow tube at opposed positions therein to span a substantial portion of the total tube circumference, whereby they are operative with respect to fluid in the tube in a range extending from a level close to empty to a level close to full. Associated with the flow tube is an electromagnet that is excited by a periodically-interrupted direct current to establish a magnetic field in the tube which is intercepted by the fluid passing therethrough to induce a signal in the electrodes. This signal is sampled during the steady state intervals of the magnetic flux to provide an output free of zero-shift error and of interference voltages.

Abstract: A precision test frequency generator capable of selectively providing a sinusoidal output wave within a frequency range simulating the output of a flowmeter yielding a sinusoidal signal whose frequency is proportional to flow rate, the signal having a noise component superimposed thereon. The generator is constituted by a stable high-frequency standard coupled to a selectable output counter providing intermediate-frequency pulses whose repetition rate is a sub-multiple of the high-frequency standard and a predetermined multiple of the desired output frequency of the generator. The pulses are converted into a triangular wave whose frequency corresponds to the desired output frequency, the triangular wave having a staircase formation whose number of steps is determined by the multiple. The triangular wave is converted into a sinusoidal wave of the same frequency with a staircase modulation component simulating the flowmeter output signal.

Abstract: A rotameter system adapted to produce an output indication that is linearly proportional to flow. The primary element of the system includes a float contained in a variable area tube through which flows the fluid to be measured, the float being raised or lowered in the tube as a function of flow rate, and a bar magnet mechanically coupled to the float and axially movable therewith. The secondary element of the system includes a rotatable follower magnet magnetically coupled to the bar magnet and a pointer mounted on the shaft of the follower magnet whereby the pointer sweeps from zero to maximum along a scale as the float travels from its low to its high position. A mass is eccentrically mounted on the shaft of the follower magnet, the position of the mass relative to the shaft axis being adjusted to produce a moment compensating for the non-linear relationship between flow rate and pointer movement.

Abstract: An interface gasket which is interposable between the conical ends of glass pipes to be joined, the gasket being compressed by means of flanges mounted on the pipe ends and interconnected by bolts. The gasket is constituted by an annular sheath whose internal diameter corresponds to the internal diameter of the pipe, the sheath being provided with a rim dimensioned to engage the end of the pipe and encircle its outer diameter, the sheath having a circular channel within which is received a compressible core ring.

Abstract: An electronic differential-pressure transmitter responsive to a difference between two pressure values to generate an output signal proportional to differential pressure for transmission to a remote station for acuating indicator or process control equipment. The transmitter is of the open-loop type that includes a pivoted force-beam to the lower end of which is applied an input force dependent on differential pressure, the resultant deflection of the beam being sensed by a motion detector coupled to the upper end thereof to produce the output signal.

Abstract: A technique for continuously indicating the concentration of ozone dissolved in water, use being made of an amperometric cell, preferably formed of a gold cathode concentrically disposed within a tubular copper anode to define an annular passage, the cathode being rotated at high speed. A sample stream of the water is directed through the passage at a predetermined flow rate whereby in the absence of dissolved ozone, the cathode is polarized, but in the presence thereof, depolarization takes place to cause a current to flow in the cell, the current being measured to provide a reliable and continuous reading of ozone concentration.

Abstract: A residual chlorine analyzer for testing chlorinated water, and including an amperometric cell whose flow passage is provided with spaced measuring and counter-electrodes both formed of copper. A sample stream diverted from the water to be tested is continuously conducted through the flow passage between the electrodes. Impressed across the electrodes is a voltage which renders the measuring electrode negative relative to the counter-electrode to an extent causing the cell to operate in a saturation voltage zone wherein the intensity of current passing through the cell is independent of changes in the impressed voltage and is proportional to the bulk concentration of the chlorine in solution. The current is measured by a meter calibrated in terms of concentration to maintain an uninterrupted, in-line check on residual chlorine in the water.

Abstract: A flowmeter of the rotameter type wherein a thin-walled variable-area glass tube containing a float is encapsulated in a transparent plastic bar having upper and lower lateral bores therein. The bores communicate with the inlet and outlet ends of the tube and are adapted to receive retainer elements for attaching the bar to a meter frame and for coupling the flow passage to inlet and outlet pipe couplers.