Abstract: A fluid strainer and flow corrector for use with a fluid flow measurement device, such as a turbine-type flow meter, consists of a generally conical grid of ribs attached to an annular base flange. The base flange of the strainer/flow corrector fits into a groove formed on the inlet side of the housing of the flow meter and is held in place by means of a flexible snap-ring. The strainer/flow corrector is arranged with its apex upstream of the flange portion with respect to the direction of fluid flow through the inlet of the flow meter. The spacing between the ribs is chosen as to block the flow of debris which might be present in the fluid flowing through the flow meter. The spacing between the ribs is also chosen to provide a desired velocity profile to the fluid. The strainer/flow corrector may be easily removed or replaced without disconnecting the flow meter from its associated pipework.

Abstract: A gas meter includes a housing made of thermoplastic material having an inside wall defining two measuring chambers and a deformable membrane disposed between the two measuring chambers. The deformable membrane is formed from a film of thermoplastic elastomer material bonded to a synthetic fiber sheet. The periphery of the membrane is hot-welded to the wall between the two measuring chambers to form a gas-tight seal between the chambers. A mechanical drive train includes at least one lever having a hinged portion made from a thermoplastic material which is hot-welded to the middle of the membrane. The train drives a mechanical distributor disposed outside the housing.

Abstract: A globe valve comprising: a control rod (70) which is movable in translation along a valve axis (XX'), handle means (90) for controlling movements of said rod in translation, a disk (74) fixed to one end of said rod; a body (12) having an inlet passage (14) and an outlet passage (16) therethrough for passing a liquid, said passages giving access to a cavity (18) which is extended via a cylindrical orifice (22) disposed along said valve axis in order to receive said rod; a cage (36) lodged inside said cavity and within which said disk is capable of being moved by axial displacement of said rod; packing (46) surrounding a portion of said rod and disposed within said cylindrical orifice; a seat (28) which is removable from said body for cooperating with said disk in a closure position, said seat having a first face defining a sealing bearing surface for cooperating with said disk and a first annular thrust bearing orifice, and a second face defining a second annular thrust bearing surface; means for defining a t

Abstract: A strip (B), generally trapezoidal in cross-section, traverses a measurement plane at the level of a line of passage (L). Two identical collimated radioactive sources (120, 121) are disposed to provide a substantially constant flux of radiation at the level of the line of passage (L). An elongate ionization chamber (310) receives at least all the radiation traversing the strip. The variations in the output signal of the ionization chamber indicate the presence in the strip of possible localized air inclusions or overweights.The invention can be applied in particular to the inspection of rubber strip intended for the manufacture of tires.

Abstract: In a parallel motion finger probe, the parallel motion arm is rigidly connected to a shaft which is supported in a linear ball sleeve bearing, instead of by a parallel motion linkage as in prior finger probes. The parallel motion arm can be biassed in either of its two opposite directions of movement by a leaf spring, whose biassing force and direction can be adjusted by a control wheel having an eccentric groove co-operating with a pin on a spring control arm to which the spring is connected. The leaf spring also serves to prevent rotation of the parallel motion arm about the axis of the bearing. Displacement of the parallel motion arm is sensed by an inductive displacement transducer of the LVDT type.

Abstract: A system for identifying which of the phases of an N-phase electric-power transmission network has experienced an electrical disturbance. For each phase there is produced a first signal representative of the transient variations of an electrical parameter of the respective phase, or of a linear combination of at least two of these parameters. A set of N second signals is generated from the product of two linear combinations of at least N-1 signals selected among the first signals. The sum of all coefficients for each linear combination is set to zero, with each of the second signals being related to a given phase. Each of the second signals is then integrated to produce a set of N third signals associated with the respective phases. A fourth signal is generated by combining all of the N first signals in a symmetrical manner with respect to all of the first signals, such that the fourth signal is independent of the associated phases.

Abstract: An electrolytic capacitor capable of withstanding high vibration environments includes a cylindrical capacitor case having an open end and a closed end, and cylindrically rolled alternate wraps of electrolyte impregnated paper and metal foil films with tabs abutting the foil films to electrically connect each of the foil films to a terminal. With the paper film on the outside of the cylindrical roll, the roll's outside diameter is tightly controlled to provide a snug fit when inserted in the case while the inside diameter of the roll is sized to provide a cylindrical volume in cubic inches equal to approximately 1.2 times the actual capacitance in farads times the desired rated voltage in volts so as to prevent a large pressure rise due to gas generation during capacitor operation. The paper films are axially longer than the other films towards the open end of the case while one of the foil films is axially longer towards the closed end of the case than the other films.

Abstract: A capacitive voltage transformer of the type having voltage divider capacitors and an electronic amplifier connected to one of the divider capacitors includes circuitry for isolating the voltage divider capacitors in the event that primary power to the voltage divider is interrupted. The circuitry measures and compares the voltage at a terminal of one of the divider capacitors and the current through the divider. If primary power to the voltage divider is interrupted, the capacitor voltage remains high while the divider current goes to zero, and the circuitry acts to isolate (such as through relay controlled switches) the divider capacitors from the electronic amplifier. This prevents any distortion from appearing in the voltages across the divider capacitors and prevents transients from developing at the input to the electronic amplifier.

Abstract: The invention relates to protective apparatus used on AC power lines. An embodiment of an apparatus for putting the invention into practice comprises impedance sensing means having an impedance characteristic defining at least three distinguishable zones in its RX diagram, and being arranged to produce respective different signals, one for each zone, indicating the zone in which the sensed impedance lies. The movement of the point representative of the apparent impedance of the line across these zones is different according to whether the movement is due to loss of synchronism between the generators supplying the line or due to power oscillations. A logic circuit is provided to detect this difference in movement.

Abstract: A pyrotechnic system comprises a plurality of pyrotechnic charges or devices 20 arranged in a matrix of recesses 14 formed in a block 12 of a synthetic resin material.In one embodiment, each device 20 contains a fast-burning pyrotechnic composition 42 arranged to be fired by an electrical primer 50, for producing a flash and/or a bang, and a slow-burning pyrotechnic composition 40 separated from the composition 42 and arranged to be ignited by the firing of the composition 42. Embedded in the composition 40 is a fine wire loop 48 which is ruptured by the burning of the composition 40. The primers 50 of the devices 20 are connected in parallel between two input terminals 52, 54, and each loop 48 is connected to short-circuit the primer 50 of the next device 20 in the firing sequence. The pyrotechnic system is thus self-sequencing.

Abstract: A digital multimeter having a tone generating circuitry and operable in a tone mode of operation for providing an audible indication when a measured electrical characteristic has a predetermined relationship with a reference value. The audible indication may be provided when a voltage level exceeds a preselectable limit, such as 1 or 2 volts. Predetermined limits for resistance values may also be selected for actuation of the audible tone. The device may be utilized as a conventional multimeter when the tone mode is non-operative.

Abstract: An adaptive differential phase shift keyed (PSK) signal demodulator which optimally tracks changes in the symbol rate of the signal. An input signal is delayed by one symbol period by passing the signal through a charge coupled device (CCD) clocked by pulses phase locked to the symbol rate (F.sub.br) by a phase locked loop, the phase locked loop also outputting clock pulses at the symbol rate to strobe a symbol decision circuit. The CCD has L stages and is clocked at a rate L.multidot.F.sub.br. As the phase locked loop tracks changes in the symbol rate, the clock pulses are varied in rate so that the CCD delay is adaptively optimized for a given symbol rate. Digital tuning is provided by an adjustable divider circuit coupling the voltage controlled oscillator of the phase locked loop to the CCD, so that by digitally selecting the division ratio the demodulator is tuned to a different symbol rate.

Abstract: In order to incorporate minor perturbations in the simulated operation of a weapon (to simulate dispersion between batches of ammunition or individual rounds, and/or the effects of changing environmental phenomena), a variable is generated at a rate related to the type of ammunition to be simulated. For ammunition exhibiting a high degree of dispersion between rounds, the variable changes rapidly and an accurately-aimed shot is deemed a hit only if the value of the variable at that instant is less than the predetermined probability of a hit with that ammunition. In the case of ammunition exhibiting some consistency between rounds but not between batches, the variable changes slowly, and its value controls the extent of a displacement applied to a laser projector before the projector is energised and scanned for a hit/miss determination.

Abstract: A capacitor which includes a case containing a capacitor element with multiple tabs extending therefrom is provided with a header which carries a pair of terminal members. Each of the terminal members has a pair of parallel connector leads extending out of the header connected by terminal portions inside the case. Each of the terminal portions includes portions parallel and nonparallel to corresponding terminal portions of the other terminal member and each of the tabs is welded to the outside of a parallel terminal portion.

Abstract: An offset circuit for use in providing an offset signal to an analog-to-digital converter. The analog-to-digital converter has an integrator for performing signal integrate operations and is connected to a digital display. The offset circuit is gated to provide a variable offset current directly to the integrator of the analog-to-digital converter, thereby eliminating adverse loading effects on the high input impedance of the analog-to-digital converter.

Abstract: A voltage offset circuit for use with an amplifier connected to receive low voltage signal inputs and operable for eliminating internal voltage offset errors of the amplifier as well as systemic voltage offsets. A variable voltage generating means is utilized to impress a voltage on an output capacitor of the amplifier which is operable in an auto-zero and measuring mode of operation. Preferably, the offset circuit and amplifier are utilized with digital meters employing an analog-to-digital converter having an auto-zero phase and measuring phase of operation.

Abstract: An optical-electronic measurement system wherein only the images of workpiece edges from which measurements are to be taken are coupled to identifiable locations on the photocathode of a processor-controlled scanner by a plurality of flexible fiber optic bundles whose object ends are placed about an inspection field so that each such edge is within the field of view of a respective bundle. Pairs of such identifiable locations are correlated to the measurements to be taken. A workpiece of known size is placed in the inspection field and the scanner photocathode is electronically scanned to determine the positions of the edge images relative to scan origins. The processor adjusts functions to relate the edge positions correctly to the known dimensions. The same measurements of workpieces of unknown dimensions are then taken by the calibrated system using the adjusted functions.

Abstract: A magnetic system for a long scale electrical meter enables four sided sensing of a coil which is completely offset from the axis of rotation has a cylindrical core pole piece magnetically coupled to first similar poles of two magnets. The core is surrounded by an inner annular air gap defined by a coaxial inner annular pole piece which is magnetically coupled to the second poles of the magnets. Radially outward is an outer annular air gap defined by a coaxial outer annular pole piece which is magnetically coupled to the first magnetic pole. Magnetic fields in the inner and outer air gaps are radial. The outer annular pole piece is closed at opposite ends by a pair of magnetically permeable discs which also are pole pieces for the first magnetic pole. Each disc is spaced apart a distance D from the nearest flat face of the inner annular pole piece to provide axial magnetic fields. Accordingly, all four sides of the coil are active.

Abstract: The variable attenuator and variable current shunt of a battery-powered auto-ranging digital multimeter uses latching relays, each of which, since it is stable in each of its two switching states, requires only a current pulse to change its state. The circuit which operates the relays provides a drive pulse only when the desired relay state differs from the actual state, thus minimizing the power required, and includes a tank circuit for minimizing disturbance to the multimeter power supply. To ensure that the tank circuit can recharge, each relay is driven by a tri-state output.