Abstract: A two-threshold pressure switch, for example for providing an early warning and an alarm condition concerning oil pressure in a hydraulic circuit for lubricating or braking a vehicle, comprises an insulating housing (1) bearing contact blades (spade-type blades 5 and 6), and receiving a moving member (14) driven by a pressure-sensitive membrane (12) and supporting contact members (16, 17) for making selective contact with a fixed conductive cup (10). In accordance with the invention, said fixed cap closes a cavity (9) in said insulating housing (1) in such a manner that said moving member (14), said contact members (16, 17), and resilient contact member holding means (22, 23) are all located on the same side of the cap (10). Said moving member (14) is in the form of a sleeve having a first one of said contact members (16) slidably mounted on its outside and having a second one of said contact members (17) slidably mounted on its inside.

Abstract: The present invention relates to a device for detecting the level of liquid in a tank. The device comprises a level detector formed of two arms pivoted on a common fixed support about first, respectively parallel, generally horizontal axes and a movable support member carrying a float adapted to follow the level of the liquid, the support member being pivoted on the two arms about second axes respectively spaced from but generally parallel to the first axes, in order that on change of level of the liquid the float follows a curved path determined by the combined pivoting of the arms, the float cooperating with a transducer adapted to generate a signal representing the position of the float.

Abstract: A device for measuring the oil level in the sump of an internal combustion engine. A resistive wire probe extends into the oil contained in the sump. The voltage across the terminals of the probe will vary according to the immersion of the probe in the oil and such voltage is transmitted to a galvanometer in the form of an oil level gauge for indicating the level of the oil to the driver. In order to prevent termination of the signal to the oil level gauge when the engine is started and pumps the oil out of the sump, a timer circuit is provided to continue the signal to the oil level gauge for a predetermined period of time after the ignition switch is closed.

Abstract: To permit accurate introduction of aerosols containing, for example, irritants or similar substances, into the pulmonary tract or airways of a patient, the breathing cycles of the patient are counted and, after a number of normal breathing cycles, and during a limited period of time in the inhalation phase of a breathing cycle, and after commencement of the inhalation phase, a predetermined quantity of aerosols is introduced to the patient by applying compressed air of controlled pressure to an atomizer or aerosol fog generator (32, 34); initiation of inhalation is sensed, for example by a pressure transducer (24), the output of which is connected to a threshold stage (50) sensing inhalation and exhalation, respectively, and setting a time delay period for example of less than half than normal duration of the inhalation phase of the patient, which then triggers a timing interval by a monostable flip-flop (56) which, during the time period thereof, applies the controlled compressed air to the atomizer (32, 34)

Abstract: Apparatus for monitoring the level of liquid in a tank or reservoir comprises a probe formed by a resistive metal element having a high temperature coefficient, and a supply means for the probe. The apparatus further comprises a voltage-frequency converter which is connected in parallel with the probe, two counters which are connected in parallel to the output of the converter, and a subtracting means connected to the outputs of the counters. A time base controls operation of the supply means during a complete cycle to effect a counting operation of the first counter for a given period of time at the beginning of a cycle, a counting operation of the second counter for the same period of time but at the end of the cycle, and operation of the subtracting means at the end of the cycle.

Abstract: A self-tapping screw. The core of the screw between adjacent threads has a constricted portion, the narrowestmost point thereof lying approximately in the center between the two adjacent threads. The core is tapered expanding outwardly from the constriction to the bases of the two adjacent threads.

Abstract: A machine for making a chain in the form of a rope comprising a forming unit which is fed intermittently with wire by a feed device and is arranged to cut successive pieces of wire and form them into open rings on a movable conveyor pin, and a linking unit which is spaced from the forming unit and is arranged to receive the rings from the conveyor pin. The linking unit includes gripper means for taking the rings from the conveyor pin and introducing them to a final receiving and holding member in alternately overturned positions so that each of the rings embraces a plurality of preceding rings. The machine includes means for feeding the receiving and holding member with reinforcing wires for the chain. The machine also includes actuator means for controlling the supply of wire, the forming unit with the conveyor pin, and the gripper means of the linking unit in a predetermined operating sequence.

Abstract: A multicomponent electrolyte with a defined potential and a display cell containing it. The multicomponent, liquid electrolyte is based on at least one metal iodide dissolved in an anhydrous organic solvent, and is characterized in that it comprises three functional components: a first metallic element M.sub.p yielding at least two iodides corresponding to different valences, and which is intended to ensure an equilibrium between the reduced forms of iodine I.sup.- and I.sub.3.sup.- ; an iodide of a second metal M.sub.t in a practically completely dissociated state, intended to fix the concentration of the anionic species I.sup.- in the electrolyte; and an iodide of a third metal M.sub.x constituting the display vehicle.

Abstract: A sampler for communicating with the interior of a vessel containing a slurry under pressure extracts a sample of the slurry from the vessel and conveys the same to a point of collection. The sampler includes a conduit having an inlet for communication with the interior of the vessel and an outlet to the exterior of the vessel, and a valve for selectively establishing and interrupting communication between the conduit inlet and the interior of the vessel. When communication is established, a sample of slurry flows into the inlet, through the conduit and to the outlet for collection, and when communication is interrupted a source of flushing liquid is coupled with the inlet to flush the conduit clean of residual sampled slurry. By virtue of introduction of flushing liquid through the conduit when slurry is not being sampled, residual slurry is prevented from settling out and/or hardening in the conduit and clogging the sampler.

Abstract: Disclosed is a device for the measurement of peak values of a nonperiodic phenomenon having a low recurrence rate. A voltage comparator has one input connected to the potential U.sub.e to be measured with its output connected through a rectifying circuit to a parallel RC circuit. The output of the rectifying circuit is also connected to a high input impedance circuit whose output which is indicative of the peak value measured is connected back to the other of the comparators inputs. The time constant of the parallel RC circuit is an inverse function of the error included in the output of the high input impedance circuit during an interval separating two peak values. The invention is particularly useful to indicate very accurately the state of discharge of lead-acid power batteries.

Abstract: A device to make a measurement of a variable quantity such as the speed of rotation of a first shaft or the speed of operation of an ignition system of an engine, wherein electrical pulses are produced at a frequency which is a function of the speed. The device comprises fixed first and second coils having axes in a common plane, and the planes of the coils are disposed at right-angles. Square waves corresponding to the pulses energize the first and second coils alternately, and each successive energizing of each coil is in an alternate direction, thus the magnetic field produced by the coils rotates continuously and rotates a disc magnet within the coils about an axis in the planes of the coils at an angular velocity which is a function of the speed. A rotor of conducting material in the form of a cylindrical cap over and about the magnet is integral with a second shaft coaxial with the magnet.

Abstract: The invention relates to a fault detector for light bulbs. It comprises an inductance connected in series between the bulb and a control switch, the arrangement being supplied with direct current. An alarm device, connected to the junction point between the bulb and inductance, is polarized in order to trip the alarm when the control switch is closed unless prevented from so doing by a tripping control circuit. The tripping control circuit responds to current flowing to the bulb subsequent to the closure of the control switch to prevent the actuation of the alarm device throughout the period of closure of the control switch.

Abstract: A transit concrete mixer is provided having a displaceable charging hopper which may be moved between a charging position wherein a discharge conduit thereof projects into the interior of the mixer drum and a relatively displaced position where the discharge conduit is removed from the drum to facilitate discharge of concrete from the drum. The charging hopper is pivotally attached to a support structure which also carries the rear end portion of the mixer drum and is selectively movable in a vertical plane about a horizontal axis. The relative location of the horizontal axis for pivoting movement of the charging hopper is located with respect to the terminal end of the hopper's discharge conduit such that the hopper and its associated conduit may be swung from one position to the other without interference with the mixer drum and its interiorally mounted blade elements. A hydraulic actuating ram is provided to facilitate the swinging movement of the charging hopper.

Abstract: A control device for digital display indicators using electromagnetic drums.An analogue/digital converter converts the information to be displayed, received in analogue form E, into digital information which can be utilized by the drums of the display device. The renewal frequency of the information delivered by the analogue/digital converter is made a function of the rate of change of the information by means of a differentiator which calculates the derivative dE/dt and a means of comparing voltages and/or frequencies and means of controlling the analogue/digital converter and/or all or a proportion of the display drums.

Abstract: The invention relates to rating monitoring devices.A first circuit emits a pulse for each centiliter (cl) of fuel consumed by a vehicle. A second input circuit emits a pulse for each meter travelled, the pulses being accumulated in a count meter. A store circuit stores a certain number of values previously contained in the count meter at the moment of the preceding pulses of cl consumed. Information about the mean distance travelled per 10 cl of fuel is obtained by producing the difference between the content of the count meter or that if the first register in a register battery, and the content of the last register of the battery. A divider allows this information to be converted into mean consumption per 100 km, this consumption being displayed in a display device.This invention finds application, in particular, to car.

Abstract: A filter media for scrubbers includes a plurality of spherical bodies made of a liquid wettable material shaped in a latticework jacket having a great circular ring from which extend arcuate bars terminating near the poles of the spherical body so formed. Spaced axially extending bars extend from the arcuate bars and terminate within the body at free ends. The arcuate bars have a cross section which tapers inwardly toward the center of the body to provide maximum capture of liquid droplets.

Abstract: A device for checking the level of a liquid in a tank, for example a car fuel tank, has an electrical resistance probe partly immersed in the liquid and energized with a constant current. The voltage across the probe at switching on is stored and used as a reference for comparing with the increased voltage after the element has been heated to a value dependent on the length of resistor cooled by the liquid.

Abstract: A transit concrete mixer includes a drum which is mounted for discharge either forwardly or reversely of the vehicle and has two sets of flights for two-stage concrete loading and discharging. One set of flights is particularly useful for carrying the aggregate from the base of the drum upwardly along the major axis of the drum and a second set of flights is adapted for receiving the aggregate and transporting it through the remaining length of the drum to the discharge opening of the drum. Thus, for relatively stiff, low slump aggregates which are useful in paving and for formless type useage, the concrete mixer unit is fully adaptable for such low slump values. Conversely, the same set of flights is adapted for charging and discharging relatively high slump values which are utilized for form type applications.

Abstract: A device for transmitting the condition of a switch comprising a first assembly consisting of a switch, a first pair of coils serially connected when the switch is closed, and a second assembly consisting of a second pair of coils, magnetically coupled to each other. A first coil of the second pair generates an alternating magnetic field. A detector is coupled to the second coil of the second pair for producing different outputs respectively when the second coil of the second pair is excited only from the field of the first coil of the second pair and when the second coil of the second pair is also excited from the second coil of the first pair.

Abstract: A device for correcting the law of deflection of an aneroid capsule comprising two or more strips of different rigidity, whereof the active ends are placed in abutment at various points of a path covered by the central part of an active diaphragm of the aneroid capsule during its deflection, associated with which or each of which is/are one or more abutments of adjustable length located in the path of deformation of the associated strip, in order to modify the active length of said strip depending on the law of deformation of the latter which it is desired to obtain.