Abstract: A cell for converting a differential pressure into an electric signal, which comprises two chambers and a sensor. The two chambers are filled with an incompressible fluid and each are closed by a respective membrane suitable for deforming under the action of an external pressure. The chambers are separated from each other by a rigid wall. The sensor associated with the wall and responsive to the pressure difference exerted across the wall, delivers an electric signal in response thereto. At least one passage is formed between the two chambers and possesses appropriate dimensions firstly for at least attenuating a parasitic pressure difference existing across the wall at a frequency that is low or zero, and secondly for allowing the sensor to detect the pressure difference exerted across the wall at higher frequencies.

Abstract: A gas volume concentration is determined. An electromagnetic radiation is emitted (state 1) through the gas volume. The radiation is filtered by temporally modulating the spectral transmission of said filter so as to obtain a temporal modulation of the energy of the radiation transmitted by the gas volume and this filter. This temporally modulated energy is detected and a signal E is extracted from it, the signal particularly depending on the concentration of the gas. The component Eac(1) of the time-variable signal and the component Edc(1) of the signal, which is not a time-variable signal are isolated. A radiation stops is emitted (state 0), and the component Eac(0) and the component Edc(0) of the signal received by the detector are isolated. The terms Eac(1)-Eac(0) and Edc(1)-Edc(0) are calculated, and the ratio (Eac(1)-Eac(0))/(Edc(1)-Edc(0)) is formed which then solely depends on the gas concentration c. From this, c is deduced.

Abstract: The invention concerns a fluid meter including a body comprising a fluid intake opening and a fluid evacuation opening aligned along a first direction A, a measuring unit formed of a fluid oscillator including at least one obstacle disposed into an oscillation chamber and which is provided with one fluid inlet and one fluid outlet, characterized in that the inlet and outlet of the fluidic oscillator are aligned along a second direction C approximately perpendicular to the first direction.

Abstract: A gas flow interrupter for a gas meter, the interrupter comprising a valve member that is movable relative to a valve seat which defines an opening for passing said gas flow, said valve member comprising firstly a membrane having a main surface including a "contact zone" portion that comes into contact with said valve seat when the interrupter is in its closed position, thereby closing said opening by means of the main surface of the valve member, and secondly a part that forms a mechanical support for the membrane and that co-operates with said membrane, wherein the metal part forming a support for the membrane has a continuous leakproof surface bounded by the contact zone so as to close the opening in the event of the membrane failing to provide sealing.

Abstract: A method for measuring a fluid flow rate between two points of a fluid flow according to which a measurement of the respective propagation times of two acoustic signals transmitted in opposite directions is combined with a measurement of acoustic phase shifts respectively induced in each signal. Each received signal is sampled and digitized and the corresponding acoustic phase shift is determined by synchronous detection. During successive iterations, a programmable phase shift dependent on the value of the acoustic phase shift obtained by synchronous detection in the previous iteration is determined for each iteration, so that the result of the synchronous detection step in the current iteration is as close as possible to zero, and the acoustic phase shift is therefore substantially the same as the last programmable phase shift.

Abstract: The invention relates to a method of measuring the flow rate of a flowing fluid on the basis of two ultrasonic signals transmitted consecutively in mutually opposite directions between two ultrasonic transducers. In the method, n clock signals CK.sub.i, where i=1 to n, that are at mutual phase offsets of 2.pi./n are formed, the first clock signal, referenced CLS, that occurs immediately after a characteristic portion the first received ultrasonic signal SIG.sub.1 appears is identified and stored, the time t.sub.1 is determined that corresponds to the sum, over an integer number m of consecutive periods, of the times elapsed between the instant at which the characteristic portion of each of the m periods of the signal SIG.sub.1 appears, and the instant at which the following signal CLS appears, likewise, for the signal SIG.sub.2 received in the opposite direction, the time t.sub.

Abstract: A single-jet liquid meter comprises a body in which a measurement chamber of substantially cylindrical shape is disposed. The chamber is fitted with a spinner having a longitudinal axis XX' and provided with blades, a liquid feed tube and a liquid discharge tube connected to the body and in alignment on an axis YY' that intersects axis XX' perpendicularly. A housing is disposed in the body around the periphery of the spinner and includes at least two slots respectively facing the feed tube and the discharge tube. The slots are designed to inject and eject the liquid flow in an inclined manner relative to the alignment axis of the tubes. At least one slot faces the feed tube and presents, to the flow of liquid coming from said tube, a shaped surface that progressively increases the speed of the flow.

Abstract: A device for detecting meter opening, the meter including at least a first structural element and a second structural element that are in a given position relative to each other when the meter is closed, said device comprising: a moving member connected to the first element and organized to take up a stable state or an unstable state as a function of the displacement of one of the structural elements relative to the other; holding means connected at least to the second element and co-operating with the moving member as a function of the displacement of one of the structural elements relative to the other, so as to hold said moving member in its unstable state and so as to enable it to go to its stable state; and detection means suitable for determining the state of the moving member and for emitting an opening signal when the moving member is in a predetermined state.

Abstract: An electronic switch comprising at least one switching device 70,72, a reference frequency source 58, a microprocessor 50 and means for applying to the microprocessor inputs representative of at least the current time and date and the latitude at which the time switch is to be used 31-36, the microprocessor being 50 responsive to the reference frequency source 58 and the current time and date inputs to implement a real time clock and calendar 62, and being arranged to calculate from the date provided by said real time clock and calendar and from the latitude input the respective times of at least one of sunrise and sunset at said location on each of a plurality of days, and to operate the switching device 70,72 at respective switching times dependent upon the calculated times.

Abstract: The invention relates to ultrasound apparatus for measuring the flow speed of a fluid, the apparatus comprising first and second ultrasound transducers disposed at points that are spaced apart in the direction of fluid flow, a transmitter module, a receiver module, and switch means organized so that each of the first and second transducers operates alternately as a transmitter and as a receiver. The transmitter module includes at least one transmission signal generator whose output is permanently connected via two logic gates each followed by a respective resistive divider bridge to a respective first terminal of the first and second transducer, and in that the first and second switch means are interposed respectively between the first terminals of said first and second transducers and the receiver module.

Abstract: A vortex fluid meter (1) includes a pipe portion (2) of constant inside diameter in which the fluid flows, at least two obstacles disposed in the middle of the flow of the fluid in said pipe portion (2) each having a generally elongate shape with longitudinal and transverse dimensions perpendicular to the direction of flow of the fluid, and adapted to generate oscillatory fluid vortices, an upstream obstacle (4) having a substantially uniform trapezoidal transverse section and a downstream obstacle (6) having a generally T-shape transverse section, and means (10, 12, 14) for detecting the signal corresponding to the oscillations of said vortices and for deducing therefrom the fluid volume or flowrate.

Abstract: The invention relates to a fluidic oscillator which is symmetrical with respective to a longitudinal symmetry plane, comprising a fluid inlet intended to form a bidimensional fluid jet which oscillates transversally with respective to the symmetry plane, an obstacle wherein is arranged a cavity which faces said fluid inlet and which is scavenged by the oscillation jet, characterized in that the obstacle has a front wall which has two so-called front surfaces substantially planar and framing the cavity, the plane of each surface being substantially perpendicular to the symmetry plane, said cavity being defined by a surface which is substantially parallel to said plane at the points where said surface joins each of said front surfaces, the obstacle also having two side walls of which said side surfaces are substantially parallel to the symmetry plane at the points where each of them joins the corresponding front surface.

Abstract: The invention is a dial inbound MIU which includes a rechargeable power supply, such as a double layer capacitor (sometimes called a "supercapacitor" or a "SuperCap") or a rechargeable battery. The power supply can be recharged from the telephone line, either from the DC current available when the phone line is on-hook or off-hook or from the AC current which is available when the telephone line is ringing.

Abstract: A physical parameter represented by variation in time of a physical magnitude G capable of varying between a minimum value G.sub.min and a maximum value G.sub.max is determined. The physical magnitude G is measured at variable time intervals referred to as sampling times. After each measurement of the physical magnitude G, the corresponding value of the physical parameter, and also the theoretical maximum error that could have occurred in the determination of the physical parameter are determined. The sampling time prior to each new measurement of the physical magnitude G is determined in such a manner as to ensure that a predetermined error threshold E.sub.max is not exceeded while determining the value of the physical parameter corresponding to the new measurement of the physical magnitude G.

Abstract: An electronic electricity meter comprising a measuring circuit and a power supply circuit. The power supply circuit comprises a main capacitor and a transformer controlled by a switching mode circuit. The transformer has an additional winding between the core and the primary and an integrator circuit rated to supply at its output a voltage image substantially proportional to the main capacitor voltage.

Abstract: The invention concerns an ultrasonic fluid counter including at least two ultrasonic transducers collectively defining an ultrasonic measuring path and emitting and receiving ultrasonic waves in the fluid along said ultrasonic measuring path according to at least one ultrasonic frequency, wherein attenuation means for attenuating parasitic ultrasonic waves generated outside said fluid counter and transmitted by the fluid according to the ultrasonic frequency or frequencies are associated with the fluid counter.

Abstract: A single jet liquid meter includes a measurement chamber connected to an injector and an ejector and equipped with a turbine having a plurality of blades, two consecutive blades being disposed at an angle .beta., the measurement chamber having two end walls opposite to each other and perpendicular to the axis of the chamber, one of the two end walls being constituted by a plate equipped with an even number of ribs, n, greater than four, projecting in the chamber and equally distributed in two sets, two consecutive ribs of the same set being disposed at an angle .alpha. which is determined by the following conditions: .alpha.=(I+2/n).beta./(n/2-1) and (n/2-1).alpha.<90.degree., where I is an integer value greater or equal to zero.

Abstract: A method for producing lutetium aluminum perovskite crystals includes heat aging the crystal melt and maintaining the interface between a crystal and the melt from which it is pulled substantially flat as the crystal is grown. In a Czochralski growth method, the rate of rotation of the crystal and its diameter are typically controllable to provide the flat interface as the crystal is pulled. Crystals produced by this method exhibit less variability in scintillation behavior which allows larger crystals to be produced from a boule making them particularly suitable for spectroscopic uses. Such crystals find uses in borehole logging tools.

Abstract: A data collection system in which a number of remote terminals (RT) transmit data packets for reception by one or more fixed data collectors (FDC) or a portable data collector (PDC). Each remote terminal (RT) transmits data in two frequency sub-bands to which the fixed and portable data collectors are respectively tuned. Channel capacity is improved in at least the fixed data collector (FDC) sub-band by the use in the remote terminal of minimum shift keying (MSK) encoding and pseudo-random variation of a frequency error applied to the packet transmission frequency for successive packets. In the fixed data collectors dual fast-Fourier transform signal processing enables the interpretation of simultaneous packets with different error frequencies. The use of a single design of remote terminal (RT) in conjunction with portable data collectors (PDC) simplifies system set-up, with the portable collectors providing coverage for those areas where a fixed data collector (FDC) network has yet to be established.