Abstract: A method of controlling the hydrocarbon content of a possible explosive mixture of air/hydrocarbon vapor circulating from an intake point into an installation fitted with a vapor intake system comprising a vapor intake circuit incorporating a suction pump enabling vapor to be circulated at a vapor flow rate QV. A device is connected to the vapor intake circuit to determine the hydrocarbon content of the aspirated vapor comprising a combination of a flow meter on the one hand and a sensor for measuring relative pressure by reference to atmospheric pressure PA on the other. The hydrocarbon content of the vapor circulating in the vapor intake circuit is determined by taking account of the density and the viscosity of this vapor, which is derived on the basis of a characteristic linked to the loss in air pressure previously stored in memory.

Abstract: A dispensing installation for fuel or other volatile liquids comprises a storage tank, a pipe and a pump for dispensing fuel, a vapor recovery pipe and pump for recovering vapor and delivering it back to the tank, and a controller maintaining the vapor delivery rate approximately equal to the liquid delivery rate. In order to check that the vapor recovery system is operating correctly, the vapor delivery rate is constantly detected and compared with a value of the liquid delivery rate. If the result of the comparison is outside a predetermined range, an alarm is triggered in order to indicate a malfunction. The predetermined range may be adjustable.

Abstract: A system for dispensing liquid hydrocarbons includes a vapour recovery circuit having a vapour/liquid separator and a vapour flow controller. The vapour/liquid separator has a receiving chamber in which liquid is collected and is mounted in the vapour recovery circuit upstream of the vapour flow controller. The recovery chamber is connected to a bleeding pipe having an inlet fitted with a non-return valve.

Abstract: A method of recovering vapors emitted while dispensing liquids into an installation. A characteristic value descriptive of the recovery operation is taken from a calibration table set up during the previous dispensing operation. During the dispensing operation, the liquid flow rate and the vapor flow rate are measured at a predetermined time interval. A new characteristic value is determined on the basis of the calibration table from the previous dispensing operation. The liquid flow rate and new characteristic value are applied to the recovery operation. A coefficient is calculated based on the differences between the measured values of the liquid flow rate and the vapor flow rate. A new calibration table is set up with values calculated using the new characteristic value, the measured flow rates, and the coefficient, in readiness for the next dispensing operation.

Abstract: A method of recovering vapor emitted in a liquid dispensing installation comprising: liquid dispensing means (P.sub.L) adapted to cause said liquid to flow with a liquid flowrate Q.sub.L ; vapor recovery means (P.sub.V) adapted to cause said vapor to flow with a vapor flowrate Q.sub.V along a pipe (120), said vapor flowrate Q.sub.V being controlled by a parameter G. According to the invention, the method includes the following steps: establishing an equation G=F (Q.sub.V, {p.sub.i }) relating the parameter G to the vapor flowrate Q.sub.V and to parameters p.sub.i characteristic of the recovery means and said pipe (120); determining an initial value {p.sub.i }.sub.o of the parameters p.sub.i ; on each dispensing k of liquid: measuring the liquid flowrate Q.sub.Lk and determining a value G.sub.k of the parameter G from the equation:G.sub.k =F (Q.sub.Lk, {p.sub.i }.sub.k-1);determining a new value {p.sub.i }.sub.k of the parameters p.sub.i to be used for the next dispensing k+1 of liquid.

Abstract: A metering system, for metering a volume V.sub.o of compressed gas supplied under high pressure from a first tank to a second tank, includes a first duct for supplying the compressed gas from the first tank to the second tank, the first duct having a pressure regulator providing a relatively high driving pressure P, and a first nozzle having a section S with an inner diameter located downstream of the pressure regulator and providing a downstream pressure p therefrom, the pressure regulator being controlled by the downstream pressure p to maintain driving pressure P so that the downstream pressure p remains less than 0.95 P. A second duct branches at one end from the first duct between the pressure regulator and the first nozzle and includes a second nozzle having a section s with an inner diameter smaller than the inner diameter of the section S of the first nozzle.

Abstract: A positive-displacement fluid flow measuring system, especially for hydrocarbon fuel dispensers. The measuring system comprises, in addition to a positive-displacement meter per se, a correction system for correcting the loss of head in the meter. The correction system comprises a differential pressure detector responsive to the difference between the pressures at the inlet and the outlet of the meter. The displacement of the membrane enables an external motor to be coupled to the shaft of the meter by means of the plates.

Abstract: A system that provides assistance in opening the main valve in a hydrocarbon dispenser nozzle. The external control member for opening the main valve acts on a pilot valve of small flow section, with the main valve being opened by fluid pressure applied to it as a result of the pilot valve being opened. The seat of the pilot valve is formed in the main valve member.

Abstract: A hinged nozzle incorporates a valve for permitting or stopping the flow of a liquid wherein the valve is responsive to the movement of a portion of the nozzle. The nozzle includes a spring which provides a motivating force for rotating the portion of the nozzle to a position which closes the valve and thus stops the flow of liquid.

Abstract: A lubricating system for the pump of the vapor recovery circuit of a nozzle for dispensing a hydrocarbon. The lubricating system comprises a capillary pipe which takes off a small flow of hydrocarbon from the main pump of the feedpipe and feeds it to the inlet of the vapor recovery pump.

Abstract: The invention relates to a valve with a control chamber and with controlled closing, especially for hydrocarbon fuel dispensers. In order to avoid abrupt closing of the valve, especially in the case of accidental or abnormal operation of the dispenser, the valve is formed by a first piston, which can cooperate with a fixed seat to block the duct, and a second piston on which the control fluid acts. The first piston is provided with a bore which is closed when the second piston is applied to the first piston. A spring is fitted between the two pistons.

Abstract: When a hydrocarbon liquid is pumped (11) for retail delivery, it is degassed by means of a vortex device (13). A control valve (21) shuts off delivery if the gas content in the degassed liquid being delivered via a main duct (16) is too high. Unlike prior systems which sense gas content only in the liquid being delivered, the present invention senses the greater gas content in the recycled gas-enriched fraction from the vortex separator device (13). This is done by means of a venturi system (19) controlling a servo-valve (25) which in turn controls the control valve (21). By using a magnified image of the gas content, the system is made more sensitive and more reliable.

Abstract: An implant for coxofemoral prosthesis comprises a slightly conical approximately straight tail that is to be engaged in the medullary cavity of the femur and a body carrying the lug or neck of a ball-and-socket joint, the body being connected to the tail by an upper part or head formed by at least one inclined projection intended to be applied against the surface of the femur cut after its resection at the level of the large trochanter. The implant is characterized in that the projection predominates over the anterior and posterior faces of the tail, and is greatly inclined from the side of the internal cortical wall to constitute a sliding shoe, allowing automatic placing of the implant on the inside the medullary canal.

Abstract: The device comprises a scale (1) and a slide (2) which are provided with electrodes arranged to form two pairs of capacitances for the measurement of the displacement of the slide on the scale (CA.sub.1 -CA.sub.2, CB.sub.1 -CB.sub.2). These measurement capacitances are connected to an electronic feed and processing circuit (3) in which they are connected in a bridge (4A, 4B) with switched reference capacitances of MOS type. In this circuit, the outputs of these bridges are connected via comparators (5A, 5B) to a processor (6) of CMOS type adapted to produce a terminal digital measurement signal by counting the periods of the signal of the measurement capacitances and by numerical interpolation within each of these periods. This interpolation is effected by balancing the capacitive bridges by means of a digital algorithm.

Abstract: Thermal energy, especially solar heat, is converted into chemical energy by being used for the endothermic dissociation of a compound which is exothermically recombinable to release at least a substantial part of that energy at a time and/or location at which the original heat source is not readily available. One or more of the dissociation products are transported to the point of utilization, preferably after interim storage, and are there recombined with one another and/or with locally available reactants to restore the original compound which is then returned, again preferably after interim storage, to the dissociation site for a repetition of the process. The exothermic reaction at the recombination site may be used to decompose a locally available compound, e.g. water, for the purpose of liberating one of its constituents, e.g. hydrogen.

Abstract: This electrical connection relates to an electrical link between a device in a metallic sheath insulated by a gas under pressure and a transformer insulated by a dielectric liquid. The connection comprises a jacket separating the interior volume of the transformer from that of the device and having a frustoconical insulating wall shielding the capacitor bushing and penetrating into the sheath. The insulating wall comprises on the outside of its base a flange having two concentric annular surfaces, one coming into contact with the sheath of the device and defining a junction plane between the interior volume of the device under gas pressure and the atmosphere, the other defining with another part a junction plane between the interior volume of the jacket filled with dielectric liquid and the atmosphere.

Abstract: In a double correlation device incorporated in a radar installation for muring distance, the transmitted high-frequency signal is modulated, by frequency displacement, by a series of pseudo-random pulses. The first correlation is carried out between each pulse of the series and a delayed version of the series, the delay being chosen to correspond to the distance zone to be swept. The resulting signal undergoes a second correlation with the signal received after reflection from the target and controls a switch in order to deduce information on the distance investigated.

Abstract: A device for dissipating the accidental over-pressure of a fluid contained in an enclosure provided with a sealing membrane intended to be deformed and broken by the over-pressure comprises a mobile piston applied against the membrane subjected to the action of a spring by means of an overcenter spring mechanism having a threshold of balance which, when exceeded, causes the sudden releasing of the piston and the breaking of the membrane, the threshold being reached by the movement of the piston under the action of the deforming of the membrane. The invention applies to the protection of the enclosures under fluid pressure.

Abstract: In a radar installation for measuring distances by transmitting and receig signal modulated by sequences of pseudo-random bits, generation both of the sequence of pseudo-random bits and of corresponding sequences with which the received radar signal is correlated, is controlled by a variable frequency clock. The frequency of the clock is varied to maximize the peak of the correlation function and the resulting frequency used to indicate the radar-target distance.