Abstract: A magnetically inductive flowmeter for flowing media, with a measuring tube, with a magnet for generating a magnetic field passing essentially perpendicular to the axis of the measuring tube and to the direction of the magnetic field, with at least two measuring electrodes arranged along a connecting line passing essentially perpendicular to the axis of the measuring tube and to the direction of the magnetic field, with a reference electrode and with a difference amplifier having a reference potential connection connected with the measuring electrodes via measuring electrode connections and serving for amplification of the measuring voltage present on the measuring electrodes.

Abstract: Surgical tubing 62 for carrying fluids to or from a surgical site. Tubing 62 also includes a pair of electrodes 64 positioned within the tubing. In operation, the electrodes are exposed to the fluids being carried to or from the surgical site so that the electrodes are electrically connectable to a flow meter 34 for indicating a flow rate of the fluids through the tubing.

Abstract: A collection reservoir 54 includes a rigid-walled cassette adapted for connection to aspiration tubing 50. The cassette also includes a pair of electrodes 36 positioned so that the electrodes are electrically connectable to a flow meter 34. In operation, the electrodes are exposed to the fluid and tissue being aspirated from the surgical site so that the flow meter indicates a flow rate of the fluid and tissue from the surgical site.

Abstract: Magnetic flow meters having a streamlined body within a flow tube provide an extended voltage path through a flowing fluid at the expense of flow passage restriction. The voltage path may extend along a circumference of an annular flow region. The use of an extended voltage sensing path increases useful signal levels, which allows for lower cost construction and lower power operation.

Abstract: A capacitive-based apparatus for measuring the volume of a fluid drop passing through an intravenous drip chamber. The apparatus includes a capacitor comprising two parallel plates that are a fixed distance apart and are positioned such that the fluid flow path in the drip chamber is between them. The fluid drop moving through the drip chamber between the plates causes the capacitance of the plates to change. This change in capacitance is measured and from it, the volume of the drop is calculated. The volumes of a series of drops are integrated to provide a measured rate of flow through the drip chamber. This measured rate of flow is compared to the programmed rate of flow and the difference is used to adjust a flow control device to obtain the desired rate of flow. The measured flow rate is also displayed.

Abstract: An electromagnetic flowmeter for measuring a flow rate in lines for conveying and distributing electrically conducting liquids, comprising a flowmeter body forming a substantially cylindrical open ended chamber, delimited by side walls of electrically insulating material. The flowmeter body accommodates a pair of facing electrodes arranged at diametrically opposite regions of said chamber and a magnetic field generator generating induction lines orientated at right angles to a line connecting the electrodes and to the chamber axis. The electrodes can be connected to a measuring device for measuring the potential difference induced between the electrodes by the fluid flow in the presence of said magnetic field. Two sleeves on the flowmeter body provide an extension of the chamber ends. The sleeves are flexible and fit hermetically over two duct portions along which the flow-rate is to be measured.

Abstract: A flow tube has a metal outer tube and is lined with an ETFE fluoropolymer that is resistant to corrosive chemicals and mechanical damage even at high temperatures. The inner surface of the metal tube is coated with a bonding metal that can be securely bonded to the outer metal tube and also forms a strong bond with ETFE fluoropolymer. After the bonding metal has been applied, a layer of a desired thickness of the ETFE fluoropolymer is molded in place to form an inner liner for the flow tube.

Abstract: The present invention is intended to achieve measurement of electrode impedance that is not easily affected by fluid noise, and to accurately detect adhesion and discriminate the type of fluid.

Abstract: In an AC electromagnetic flowmeter, a method is proposed for obtaining reliable measurement of flow across a variety of flow rates which has good stability and is immune from noise.

Abstract: A magnetoinductive flowmeter for moving fluids, incorporating a sensor unit and a processing and power supply unit, the sensor unit encompassing a measuring tube, field coils which serve to generate a periodically alternating magnetic field in a direction at least essentially perpendicular to the axis of the measuring tube, and two measuring electrodes positioned along a line that extends at least essentially in a direction perpendicular to the axis of the measuring tube and perpendicular to the vector of the magnetic field, with field-coil feed lines connecting the field coils of the sensor unit to the processing and power supply unit. The sensor unit encompasses a sensor-data memory module in which specific parameters of the sensor unit are stored and from which the stored specific parameters can be transferred to the processing and power supply unit. This permits the simple adaptation of an existing sensor unit to a new processing power supply unit or vice versa.

Abstract: The flowmeter comprises a flow sensor with a flow tube, two coils, and two measuring electrodes as well as measuring and control electronics. The method serves to compensate interfering potentials that are caused by inductive and/or capacitive interference arising from the coil leads and/or by particles of foreign matter or air bubbles in the liquid to be measured and/or by coatings on the measuring electrodes. During first subcycles of the excitation current, a measurement signal proportional to volumetric flow rate is computed as usual. During second subcycles of the excitation current, at least one voltage pulse is applied to at least one of the measuring electrodes.

Abstract: The current-regulator circuit generates a supply current by means of clocked setting electronics and by means of control electronics which deliver a pulse-width-modulated clock signal. The setting electronics comprise a storage choke and a smoothing capacitor coupled thereto. By means of two electronic switches of the setting electronics, a first potential and a second potential are applied alternately to the storage choke, so that a current flowing through the storage choke has an AC component flowing through the smoothing capacitor and a DC component flowing through the excitation circuit, the DC component serving as supply current. The current-regulator circuit proposed is particularly suitable for use in an intrinsically safe and/or field-bus-enabled electromagnetic flowmeter.

Abstract: A magnetic flow sensor using a permanent magnet to provide the magnetic flux is configured to compensate for electrode related drifts. The electrode signals are cyclically short circuited and the flow rate related voltages are isolated from various drift signals during short signal sampling periods. Some versions of the invention use multiple sensing heads in a single sensor to increase the magnitude of the flow related signal.

Abstract: A magneto-inductive flowmeter for measuring the flow rate of fluids, incorporates a measuring tube, two magnetic poles externally contacting the measuring tube, and two interconnected return plates. Each magnetic pole includes a field coil and a supporting plate-metal pole shoe. Each pole shoe is connected in the area of the opening of the field coil supporting the associated pole shoe with a return plate and features in the area outside the opening of the field coil supporting the associated pole shoe, and connecting to the same, sections which butt against the measuring tube.

Abstract: According to the principles of the invention, there is provided a system that identifies spurious noise values in an input signal and replaces them with substitute values representative of the spurious-noise-free signal. The system is activated when the signal deviation exceeds a predetermined threshold, otherwise passing the signal unchanged. The substituted representative values are determined based on historical signal data, preferably a moving average with a fixed window. There is further provided a maximum glitch width which prevents inadvertent suppression of a true step in the input signal, and a relaxation time which prevents consecutive filter activations from unduly masking the input signal.

Abstract: An inline electromagnetic flow probe, and its corresponding flow transducer, incorporate mutually compatible features that permit a single transducer to identify which of a plurality of types of flow probes has been inserted into the transducer.

Abstract: A vortex flow meter includes a measuring tube in which a fluid is carried, a vortex generator provided in the measuring tube for developing a Karman vortex in the fluid, a magnetic field generator generating a magnetic field across the measuring tube downstream of the vortex generator, a pair of electromotive force measuring electrodes provided downstream of the vortex generator for measuring an electromotive force generated by the Karman vortex passing across the magnetic field, a pair of reference electrodes provided at locations upstream and downstream of the electromotive force measuring electrodes, respectively, for measuring a potential at each location, and a detector circuit electrically connected to the electromotive force measuring electrodes and the reference electrodes for calculating the flow of the fluid from the electromotive force and the potential measured by the reference electrodes.

Abstract: A magnetic flow sensor is configured to compensate for electrode related drifts by connecting the electrodes either to each other or to a reference voltage during most of an operating duty cycle. Some versions of the invention use multiple sensing heads in a single sensor to increase the magnitude of the flow related signal, either by interconnecting ones of the electrodes or by externally summing the signals. Additionally, some versions of the sensor can be used with weakly electrically conducting flow conduits, such as blood vessels.

Abstract: A magnetic flow sensor is configured to compensate for electrode related drifts by connecting the electrodes either to each other or to a reference voltage during most of an operating duty cycle. Some versions of the invention use multiple sensing heads in a single sensor to increase the magnitude of the flow related signal, either by interconnecting ones of the electrodes or by externally summing the signals. Additionally, some versions of the sensor can be used with weakly electrically conducting flow conduits, such as blood vessels.

Abstract: This method reduces the cost and complexity of the manufacture of an electromagnetic flow sensor having a measuring tube (1) with an insulating liner (12) having an open-pore reinforcing body (13) embedded therein. The liner is produced in situ in the prefabricated support tube (11) rather than inserting it therein as a prefabricated component. A sintering space (41) is formed in the support tube (11) by inserting a sintering mandrel (411) with a smallest diameter greater than the smallest inside diameter of the liner (12) into the support tube (11) and fixing it therein. The support tube (11) is closed, leaving one filling aperture (414) for a granular material to be sintered. The reinforcing body (13) is formed in the support tube (11) in such a manner that it fits its lumen, by introducing the material to be sintered into the sintering space (41), sintering the material and removing the mandrel (411).

Abstract: An inline electromagnetic flow probe, and its corresponding flow transducer, incorporate mutually compatible features that permit a single transducer to identify which of a plurality of types of flow probes has been inserted into the transducer.

Abstract: An improvement over conventional electromagnetic flowmeters which signal a measure of flow rate by controlling the current in a current signalling loop (also known as a sensing loop) and in which power for the flowmeter is derived from the current in the signalling/sensing loop. Conventional electromagnetic flowmeters use a standard current range (typically 4-20 mA), in which zero flow is indicated by controlling the current in the loop to a minimum predeterimened value and maximum flow is indicated by controlling the current to a maximum predetermined value. In the improved flowmeter of the invention, minimum flow is signalled by maximum current in the signalling/sensing loop and maximum flow is signalled by minimum current. This has been found to enable improved accuracy to be obtained at low flow rates without requiring complex flowmeter circuitry.

Abstract: An inductive flow meter has a measurement channel body with an electrically insulating inner wall and defining a flow channel that extends along a longitudinal axis. A pair of electrodes is exposed to said flow channel at its inner wall so as to be in contact with a medium flowing within said channel, and are diametrically opposed to each other in a transverse plane perpendicular to the longitudinal axis. A pair of magnetic pole shoes of a magnetic field generating system is arranged on opposite sides of the measurement channel body and centered about the transverse plane containing the electrodes, with the shoes adapted to generate a magnetic field across the flow channel section, such that lines of the magnetic field extend essentially perpendicular to both the longitudinal axis and a straight line between the electrodes. Two associated, electrically conductive signal lines extend between the electrodes and associated connector lugs on an outer surface of the measurement channel body.

Abstract: A magneto-inductive flowmeter for measuring the flow rate of fluids, incorporates a measuring tube, two magnetic poles externally contacting the measuring tube, and two interconnected return plates. Each magnetic pole includes a field coil and a supporting plate-metal pole shoe. Each pole shoe is connected in the area of the opening of the field coil supporting the associated pole shoe with a return plate and features in the area outside the opening of the field coil supporting the associated pole shoe, and connecting to the same, sections which butt against the measuring tube.

Abstract: The electrode assembly (3, 3′, 3″) avoids the reduction of the insulation resistance of electrodes (4, 4′, 41″) by a suitable design. The assembly is part of an electromagnetic flow sensor comprising a tube (1, 1′, 1″) made of a metallic, nonferromagnetic material. The tube has an insulating liner (2, 2′, 2″); an external surface (11) of the tube is untreated. Each electrode (4, 4′, 4″) has a head (41, 41′, 41″) and a shank (42, 42′, 42″) provided with a thread (43) and having a smaller diameter than the head. The electrode is fitted in hole (12) of the tube wall by means of an insulating body (5, 5′, 5″). The body has a disk-shaped portion (51, 51′, 51″) and a tubular extension (52, 52′, 52″) fitting the hole. A cylindrical part (6, 6′, 6″) is made of an insulating, hydrophobic material and has a bottom (61) and a wall portion (62).

Abstract: An electromagnetic flow-rate measurement system for measuring flow-rate values of a fluid is disclosed. Detection units measure the flow-rate values of the fluid. A meter board, which connects to the detection units via a common bus-line, collects the flow-rate values. The detection units include a first communications circuit which is connected between two ends of an exciting coil and server both to transmit flow-rate signals or cumulative flow-rate signals to a meter board in synchronization with an alternating waveform voltage of a common bus-line, and to receive signals from the meter board in synchronization with the alternating waveform voltage. The meter board encompasses a second communications circuit which is connected to the common bus-line and serves both to transmit signals to the plurality of detection units in synchronization with the alternating-current waveform voltage, and to receive signals from the detection units in synchronization with the alternating waveform voltage.