Abstract: A method for detecting the location of a leak in a pneumatic tire. A leaking tire is filled with a suspension which is capable of flowing through a leak of the tire and staining the perimeter of the leak at the outside surface of the tire. The suspension is a powdered fluorescent pigment of small particle size suspended in a propellant and the air inside of the tire. A portable container is provided for storing the powdered pigment and propellant. The container has an outlet valve for controlling the release of the pigment and propellant from the container. One end of a flexible tube is connected to the outlet valve of the container and a fitting at the other end of the tube is connected to an inlet valve of the tire. The fitting has a means for sealing the attachment of the tube to the tire inlet valve and a means for opening the tire inlet valve. When the outlet valve of the container is opened, the pigment and propellant flow into the tire and combine with the air in the tire to form the suspension.

Abstract: A method and apparatus for measuring viscosity of an oil at low temperature and low shear stress. It employs a columnar container of the oil with vertically spaced temperature control devices to apply different cooling histories simultaneously. After the cooling histories have been applied, the viscosity of all the different histories is determined by measuring the instantaneous velocity of a probe moving through the column of oil under a constant force.

Abstract: An apparatus and method are provided for measuring apparent viscosities of conventional as well as unconventional slurries. In particular, slurries which utilize supercritical liquid CO.sub.2 as a carrier fluid can be tested at a variety of concentrations and particle size distributions. The method is capable of forming the slurry mixture and maintaining the solids in relatively uniform suspension. A sensing element, which is a vibrating-rod, is used as a viscosity detector.

Abstract: Method of measuring the time of coagulation of samples of fluid products such as, for example, samples of blood plasma, wherein the dose of liquid substance to be analyzed is introduced into a small cup (1) the base (1a) of which is shaped to serve as a circular rolling path (1b) for a ball (2) disposed in the lower part of the cup which is actuated with a non-rotary circular movement be means of an eccentric (3-3a) causing a rotation of the ball in a circular path in the base of the cup. The gradual slowing and/or halting of the rotary movement of the ball caused by the thickening or coagulation of the sample of the medium or liquid substance contained in the cup, for example following the introduction of a reactant, is ascertainable visually or, preferably, by any suitable automatic detection system.

Abstract: A method and apparatus for rapidly determining the moisture content of a substance. An area of one surface only of the substance is subjected to a predetermined intensity of radiant energy for a selected period of time and the temperature rise is measured. The rise in the surface temperature of the substance such as pieces of wood, is approximately inversely proportional to the moisture content of the wood and thus is easily determined. This is obtainable by transporting the substance on a fixed speed conveyor past a heat source, variations in the rise and fall in the surface temperature readings immediately following the application of heat are representative of its moisture content; low readings indicating high moisture content while high readings being indicative of low moisture content.

Abstract: The invention relates to a feeler pin device for the quality and/or quantity testing, and/or the levelling of cigarettes. The device comprises a plurality of feeler pins which are set in a substantially co-axial relation with the cigarettes to be tested or levelled, and which are moved from a retracted rest position axially toward the respective cigarettes, so as to contact the cigarette ends, whereby they apply thereon an elastic pressure, such as to shift the cigarette or the cigarettes against a suitable abutment for aligning same, and/or they signal the presence or absence of cigarettes, or the degree of filling of the ends thereof, and/or the presence or the absence of the filter tip, by the aid of means responsive to the stroke length of each feeler pin with respect to its support.

Abstract: The invention relates to the measurement of the fuel consumption of a combustion engine. It relates to an apparatus which comprises two flowmeters (24, 26) which give temperature-compensated signals because their elliptical rotors 28 have the same coefficient of expansion as their chambers. Temperature sensors 36 permit the flow rates to be corrected before they are subtracted, the operations being carried out by a microcomputer 34. Application to the measurement of the fuel consumption of automobile vehicles.

Abstract: A test site for gauging the adhesion between the insulating layers and the metal layers used to produce the various devices on a semiconductor chip. The chip-sized test site can be formed along with the product chips on the product wafers. The layers of the test site are arranged such that a first polyimide layer forms a first test interface with a silicon nitride layer and a second test interface with a first metal layer, and a second polyimide layer forms a third test interface with a second metal layer, a fourth test interface with the first polyimide layer, and a fifth test interface with the silicon nitride layer. These five interfaces form a single continuous adhesion test interface. During a 90.degree. peel test, the layers of the test site will sequentially separate along this interface. Thus, the adhesion at five different interfaces can be tested during a single peel test on a chip-sized test site.

Abstract: The disclosed orbital ball flow detectors include a photoelectric ball sensor applicable to both axial-flow and toroidal forms, wherein reflection occurs at the ball. Also disclosed are photoelectric ball sensors of both the transmission and reflection types in which the light path extends through pellucid material of the passage means that forms a track against which the ball bears as it orbits. There may be a swirl in the flow pattern of the fluid; and then multiple pairs of orbital ball flow detectors, each carrying part of the total flow and having mutually opposite orbit directions, provide improved accuracy.

Abstract: The invention relates to an apparatus for dynamically determining the local weight per unit area of sheet-like material, for example, paper, in which the sheet-like material is exposed to sound waves from a sound transmitter. The portion of sound transmitted and/or reflected by the sheet-like material is measured by aid of a receiver and the weight per unit area determined from the measuring signal. In order to avoid disturbances of the measuring signal due to superimposed sound waves and in order to obtain high local resolution even in the case of quickly moving material to be measured, the transmitter, material to be measured and possibly the receiver as well are arranged on a slant relative to each other in such a way that the portions of sound reflected on these elements are faded out of the path of rays between the transmitter and the receiver. Means are additionally provided to prevent the faded out portions of sound from returning to the path of rays between the transmitter and the receiver.

Abstract: An ultrasonic probe for inspecting a weld between a cylinder (C) and a pipe (P) is caused to move in a holder at the end of an arm (11) pivoted at a point on the axis (Z) of the pipe so that the line (12) of transmission from probe penetrates the weld and, when projected beyond the weld, intersects the axis (Z) of the pipe (P) for all positions of the arm.

Abstract: A small, simple, yet accurate probe for producing a sector scan for ultrasonic medical diagnostic apparatus is provided by positioning a curved transducer array within the probe opposite a window, and filling the probe with a fluid having an acoustic velocity on the order of 0.5.times.10.sup.5 cm/sec. This combination is made possible by forming the window from a stiff polyionomer material whose acoustic velocity is closed to that of human skin, yet which is stiff enough even when thin to be essentially non-deformable in clinical use. Grating lobes of the ultrasonic beam, as well as the scatter produced within the probe by the high reflectivity of the window material, are absorbed by coating or lining the inner side walls of the probe with an open-celled polyether urethane foam having a cell diameter slightly smaller than one wavelength of the ultrasound in the probe fluid.

Abstract: An optical pressure sensor (1) is used for determining pressures and differential pressures of explosive liquids and gases and comprises a translucent body (2), having pressure measurement chambers (5, 7) formed as continuous holes. Sealing plates (3, 4), seal the pressure measurement chambers from the outside environment. The liquid or gaseous medium, introduced through inlet openings (9, 11) into the pressure measurement chambers and subjected to pressure, produces internal stresses in the body (2) so that the condition of polarization of polarized light (17), by which the body is irradiated, varies with the pressure in the pressure measurement chambers. An analyzer (18) filters from the light having a pressure-dependent condition of polarization linearly polarized light, whose intensity varies with the pressure of the medium to be determined. The pressure sensor is constructed in a simple manner and reacts with a high degree of sensitivity and accuracy to pressures and differential pressures.

Abstract: A pressure gage particularly suitable in a variable temperature environment includes a body carrying two force rods. One of the force rods is coupled to the source of pressure to be measured while the second, of similar length and parallel to the first, is separated from the pressure to be measured. The total strain on both rods is affected by the same factors except that the rod coupled to the source of pressure is also affected by that source of pressure. When the strain of the two rods are subtracted the resultant strain is attributed only to the measured pressure.

Abstract: A sensing cell for sensing pressures which includes a housing and a diaphragm that deflects relative to a housing surface under pressure differentials, the movement of the diaphragm is sensed to provide indications of pressure changes. The diaphragm has a center disc like deflecting portion, an outer peripheral support ring that is clamped for supporting the diaphragm in a housing, and an integral, reduced section web joining the center portion and the support ring. The reduced cross section web causes the diaphragm to act as a free edge diaphragm during deflection. The housing and/or the diaphragm are configured so that at near a rated overpressure stop means support the central disc portion at its annular edge where the web joins the central disc portion to reduce the maximum stress on the web and thus prevent over stressing of the web portion of the diaphragm under maximum overpressures, to reduce hysteresis and innaccuracies.

Abstract: An apparatus for and a method of extracting physiological liquids and adding of a coagulation preventing element thereto such to control the added quantity of the coagulation preventing agent in accordance with the quantity of flow of the physiological liquid such that at all times a set ratio between the flow quantity of the physiological liquid and of the coagulation preventing agent is maintained. This allows an improvement of the yield and of the durability of the physiological liquid. The apparatus comprises an emitter element, a transducer including two oscillators which are to be applied onto a plastic hose flowed through by the physiological liquid, comprises further a demodulating circuit which generates a signal which is proportional to the velocity of speed within the plastic hose, comprises further a converter which generates a DC-signal which is proportional to the flow quantity. The measuring proceeds without contact and without any influence onto the medium being measured.

Abstract: The instrument disclosed herein is designed for measuring flow rates and densities of moving fluid streams, including liquids, gases, slurries, and fluids which contain solid materials. In one embodiment of this instrument, a conduit section, which has a 90 degree bend therein, is placed in a transfer line which carries the fluid stream to its use point. Defined within the conduit section is a chamber, which is located at the bend in the conduit. Installed within the chamber is a force measuring transducer and a piston, which is in contact with the diaphragm assembly of the transducer. In operation, part of the moving fluid is diverted into the chamber, to equalize fluid pressure across the diaphragm assembly of the transducer and the piston. This removes the effect of fluid pressure on the flow rate and density measurement, and allows the moving fluid to displace the piston by the force exerted by the fluid.

Abstract: Apparatus for sampling a material in a container both in a laboratory environment and in a field environment is shown. The apparatus includes a portable pump for generating either a partial pressure with respect to atmosphere or a partial vacuum with respect to atmosphere. The partial vacuum is used to force the material from the container through a collection tube into a specimen bottle. When the material in the container is too viscous to be directly drawn into the specimen bottle, a pressure is applied to one end of the collection tube and the material in the collection tube is driven into the specimen bottle. The footpump is modified to provide both a pressure and a vacuum nozzle and is easily portable to a remote location site.

Abstract: A gear assembly for high-speed transmission between either two parallel shafts or two intersecting shafts comprising two meshing gears, one mounted to a drive shaft and the other mounted to a driven shaft, each of the gears having coaxially disposed first and second toothed portions which differ from each other in that the teeth of the first toothed portion are cut at a first inclination angle and the teeth of the second toothed portion are cut at a second inclination angle different from the first inclination angle. One of the meshing gears is fixed to its shaft so as to be non-displaceable axially, while the other is mounted so as to be axially displaceable with respect to the fixed gear.

Abstract: To facilitate manufacture of accurately formed tracks (6) within a circulating nut (10) on a spindle (1), the nut is formed with insert strips (4) shaped to receive the balls (3), the insert strips defining said track and, for example, being formed as part semi-circular trough-like sheet steel elements bent into spiral form, with circulating return portions (7) for the balls formed in either the nut, or extending from, and joining adjacent terminal portions of the strips. To prevent loss of balls, an elastic, e.g. plastic tape (189) with laterally projecting wings (19) is positioned between the tracks (6) defined by adjacent strips, partly overlapping the balls (3) in the tracks, additionally providing reservoirs for lubricant and excluding contamination of the track within the nut by dirt, grit and the like.

Abstract: A lubricating structure of a differential carrier includes a drive pinion shaft attaching portion, an oil supply hole and an oil return hole extended respectively along and provided on both sides of the attaching portion and a ring gear attaching portion formed to extend the axis of a ring gear in the direction crossing these holes. A gap between a portion located on the lower side of the oil supply hole in a member surrounding the ring gear attaching portion and the ring gear disposed in the attaching portion is formed so as to be larger than that between a portion located on the upper side of the oil supply hole in the member and the ring gear. The oil supply hole is formed to give an inclination downward in front when the differential carrier is mounted on a car body.

Abstract: In a dry tuned gyro, two pairs of coils 44 having ferromagnetic cores 46 are provided as torquers, which act on a ferromagnetic gyro rotor 36. The coils 44 are each angularly offset by 90.degree.. Opposite coils 44 are energized in opposite directions by a direct-current signal and provide a torque. Due to the core 46 only low currents are required for that. The coils 44 are supported on sensors 48, which respond to forces of reaction. The sensors 48 include crystal oscillators and supply a torque signal in the form of a frequency. Simultaneously alternating currents are applied to the pairs of coils 44 and act as position pick-offs as well due to the variation of the inductivities. The pick-off signal from one of the pairs of coils 44 controls the direct-current signal for the other pair, and vice versa.

Abstract: A shift lever mechanism for use with a vehicle automatic transmission. A pivoting lever supports an upwardly spring biased plunger for fore and aft travel in a detent slot. The detent slot is formed in a cylindrical plate portion formed substantially concentric with the transverse pivot axis of the lever. The plunger is made from plastic material and is formed with a pair of transverse wall portions each having a plurality of mirror image step-up blocks. The slot includes a series of interconnected notches having progressively decreasing widths in both its fore and aft directions from a central dual mode notch. The notches define locating edges which successively contact and position the upwardly biased plunger step-up blocks during either fore or aft travel from the central notch to define a plurality of modes for the transmission.

Abstract: A push-button control for a sewing machine is provided with a spring system which returns slidable push-buttons from actuated to unactuated positions, and includes individual wire springs supported within grooves in a fixed member and preloaded against extended portions of the buttons.

Abstract: In a tilt steering equipment including a main bracket mounted to a vehicle body; an upper bracket with a steering wheel, which is pivoted at the main bracket around a tilt center; and a driving means supported by the main bracket to tilt the upper bracket against the main bracket, the driving means in fixed to the main bracket and has a drive center spaced from the tilt center and an engaging pin which rotates around the drive center. The upper bracket has an engaging slotted hole in which the engaging pin is inserted. According to the tilt steering equipment of this invention, the drive center of the driving means is spaced from the tilt center. Therefore, it is easy to assemble the equipment with high accuracy and a smaller torque is enough to tilt the upper bracket to the main bracket.

Abstract: A foot operated vehicle parking brake mechanism comprises a brake pedal lever and a brake cable actuator pivotal about a common axis, the brake pedal lever being operable upon depression to displace the cable actuator to a cable tensioning position in which the vehicle brake is set. The cable actuator and pedal lever are independently releaseably retained in the cable tensioning and depressed positions and, respectively, against the bias of the tensioned cable and a pedal lever biasing spring. A manually operable release mechanism operates to release the pedal lever from its depressed position and, during return of the pedal lever to its retracted position, the pedal lever operates to release the cable actuator for return to its released position.

Abstract: A transmission system, in particular for motor vehicles having at least two driven axles, comprises a transmission (1) and two differentials (2, 3) in tandem arrangement, of which at least the transmission (1) is designed as planetary gear. All three gears (1, 2, 3) are arranged coaxially. An arrangement requiring exceptionally little space is obtained when the differentials (2, 3) are likewise designed as planetary gears and when the transmission (1) is arranged between the two differentials (2, 3). The transmission comprises two coaxially arranged hollow shafts (12, 16) passing through the differential (2) following the transmission, and the transmission and the differential (2) have a common planet carrier (21). The two differentials are coupled by the fact that their internal gears (28, 30) are mounted on a common hollow body (29) embracing the transmission (1).

Abstract: Limited slip differential mechanisms and assembly techniques therefore are disclosed providing enhanced strength and durability without increase in over all size. Positioning the parting plane of a two part differential mechanism case outside the chain of elements transmitting the torque through the differential mechanism while at the same time increasing the size of side and pinion gears within the case and modifying both the case interior machining technique and the technique for assembling the components within the case yields the strength and durability advantages.

Abstract: A pneumatic throttle valve actuator for an automatic power transmission mechanism for use with a supercharged or turbocharged internal combustion engine wherein the relationship between manifold pressure and actuator force is changed when the engine manifold pressure changes from a positive pressure to a negative pressure or vice-versa. A correct shift point signal and a correct pressure regulator output thus are maintained regardless of whether the turbocharger or supercharger is active or inactive.

Abstract: A control system and method for a vehicular propulsion system which includes a continuously variable ratio transmission (CVT) and an engine having a relatively steep torque-speed characteristic. Attenuation of the accelerator pedal output--which directly controls the transmission ratio--when the engine is operating in the highly sensitive "critical speed range" spanning the steep portion of its torque-speed characteristic, serves to smooth vehicle responsiveness and driveability, and improve control.

Abstract: An infinitely variable belt-drive transmission is provide with a D/L-range as one of operating ranges. The system has a transmission ratio control valve comprising a spool which is moved in the downshift direction to downshift the transmission and in the upshift direction opposite to the downshift direction to upshift the transmission. An actuator is provided for moving the spool. When an accelerator pedal of a motor vehicle is depressed at the D/L-range, the actuator operates to move the spool in the downshift direction and when the accelerator pedal is released at the D/L-range, the actuator operates to move the spool in the upshift direction.

Abstract: A lever operating device in an excavator comprises an accelerator arm interlocked with an accelerator lever to pivot fore-and-aft, a pivotable arm interlocked with a control lever for a controlling valve of a drive unit in a working section to pivot fore-and-aft, a machine frame which bears the accelerator arm and pivotable arm arranged left and right in parallel and an abutting plate provided integrally with the accelerator arm to extend to the pivotable arm side, whereby the extending end of the abutting plate is located in the front position in the pivotal direction of turning on the controlling valve of the pivotable arm.

Abstract: A ratchet wrench which includes a handle connected to a housing having a plurality of inwardly projecting teeth on its inner side, and a torgue transmitting member provided in the housing which has a shaft extending therefrom. The cylindrical body has as axial groove opening at its peripheral surface, a bore extending radially outward to communicate with the groove, and a protrusion means received in the bore and biassed radially. The groove is confined by two diverging surfaces, and two converging surfaces extending from the diverging surfaces respectively. A pawl is axially disposed in the groove. It has a first longitudinal tapered end portion to engage with the teeth, a second longitudinal opposite end portion to engage with corners of the groove, and a recess in the second end portion for engaging with the protrusion means. The second end portion is movable between two corners of the groove to change the engaging position of the first end portion with respect to teeth.

Abstract: A boring machine having a tapered shank received in a spindle with a pre-loaded adjustable boring bar carrying said tapered shank and a non-rotating torque arm for controlling a pre-loaded adjustable boring bar pivotally secured to a tapered shank to pivot the boring bar.

Abstract: A two-spindle machine tool having a fixed first headstock with a main spindle extending in a direction Z and with a chuck, and two tool heads with turrets further has a movable second headstock with a main spindle extending in the direction Z and with a chuck, the second headstock and the two tool heads being supported on respective slide mechanisms which enable them to move in the direction Z and also in a direction X perpendicular thereto relative to the first headstock, and which are so positioned as to enable the two headstocks and two tool heads to function in respective operational regions enabling machining tools held by the turrets to perform various modes of machining including independent but simultaneous machining of respective workpieces held in the two chucks and simultaneous or successive machining of a single workpiece held by either of the chucks.

Abstract: A cat-head type machine tool is controlled by an electronic control system (28, 31) so as to allow relative movement between the rotating tools (11, 12) and the stationary workpiece (22) within a revolution of the tools, such that non-uniform and/or barrelled or oval profiles may be machined on a cyclindrical workpiece. This is particularly useful for the high speed production of pistons for internal combustion engines where such profiles can give a piston improved performance.

Abstract: A cross slide contour forming box tool which can be applied to automatic screw machines for contour forming desired contours on the outside of a workpiece. The contour forming tool is positioned to a transverse slide perpendicular to the drive axis. The transverse slide is driven by a pin and cam groove in the face of a cam so that the contour forming tool is positioned in accordance with the shape of the cam groove. The workpiece is rotated relative to the contour forming tool and the desired contour is formed on the surface of the workpiece.

Abstract: A device for continuously cutting out a waste strip between two usable strips of sheet or web material, including a cutting wheel disposed intermediate two counterpart wheels in closely adjacent alignment and with overlapping edges, and a plurality of pressing devices adapted for compressing the sheet or web material in the region of cutting, wherein the cutting wheel and the two counterpart wheels are rotatable in opposite directions.

Abstract: A household slicing machine wherein a disc-shaped knife can be driven to rotate in a first vertical plane and a stop for the foodstuff to be sliced is mounted in the housing in a second vertical plane which is parallel to the first plane. The stop is shiftable at right angles to the first plane to change the thickness of the slices and the adjusting device which shifts the stop relative to the knife has a pair of coaxial sleeves rotatably mounted on the stop and defining a helical path having several sections with different leads. A stationary carrier is provided on a working platform in front of the support and has a follower which extends into the helical path.

Abstract: An apparatus for producing sloping roof insulation panels and more particularly, roof insulation panels made of glass fiber material covered by a base cap layer. Such apparatus includes a circular saw capable of producing a groove in at least one of the side surfaces of the panel and a band saw for cutting the panel into a first portion including at least part of the top surface of the panel and a second portion including at least a part of the bottom surface of the panel. The band saw is located in alignment with the groove or grooves produced by the circular saw.

Abstract: In an electronic musical instrument which generates a musical waveform by calculating the waveform amplitude value at each sample point through Fourier synthesis, there is provided a musical waveform generator for caculating and synthesizing a temporally varying musical waveform at a plurality of sample points, memory circuits for storing two kinds of musical waveforms obtained by the musical waveform generator one after the other and an interpolation circuit for interpolating the two musical waveforms at time intervals shorter than the time intervals used in the musical waveform generator.

Abstract: In response to the data input from a keyboard, a tone clock generator generates a tone clock signal. The tone clock signal is counted by a waveform step counter. The output of the counter is used for making an access to a waveform memory. The waveform memory stores first and second waveform data of which the periods respectively are divided into a different number of addresses. One of the first and second waveform data read out from the waveform memory by the output of the counter is selected, according to the key-in data.

Abstract: A musical instrument with a plurality of strings comprises a body assembly, a neck, and a headpiece, with the body assembly comprising a cylindrical body, a membrane covering the top of the cylindrical body, and a head rim extending along the circumference of the top of the cylindrical body holding the membrane over the cylindrical body, with a plurality of tuning lug assemblies secured into the side of the head rim.

Abstract: The electronic metronome has a baton reciprocatingly driven by a pulse-drive stepper motor powered by a varying voltage source. Drive circuitry generates and applies drive pulses to the stepper motor, each drive pulse being composed of a plurality of individual pulses having a pulse width which varies in accordance with variations of the voltage source and with the selected tempo at which the baton reciprocates. The stepper motor is thus driven at a constant torque-frequency characteristic despite fluctuations in the power source voltage and the tempo of the metronome.

Abstract: A modification to a reel type staple cutter that includes a housing surrounding the cutter reel. The housing has a cam slot sized to permit passage of a single tow but to prevent passage of a knot tieing together two ends of tow. As the cutter turns the knot slides along the outside of the slot reaching the top of the housing. The knot remains on top of the housing until the ends of the knot are cut. Means are provided to remove the knot.

Abstract: A dual ammunition feed for automatic weapons includes a positioning device for the ammunition wherein a central positioning sprocket unit interacts with two feed sprocket units in two separate feed casings to allow for loading with two different types of ammunition. The feed casings are tiltable into and out of engagement with the positioning device, the tilting of a particular feed casing into engagement with the positioning device being followed by the simultaneous disengagement of the other feed casing from the positioning device. The tilting of a particular feed casing into engagement further results in the coupling of the engaged feed casing's feed sprocket unit with a reducing transmission driven by an external motor, and in a change in the rotational direction of the central positioning sprocket unit such that the central positioning sprocket unit always rotates in an opposite direction from that of the feed sprocket unit of the particular feed casing which is engaged.

Abstract: An actuator of the type used in aircraft flight controls and similar applications is combined with a fail-passive electrohydraulic control system (11) that affords the usual actuator response to electrical input commands during normal operation, and responds to any of a number of possible failure conditions to dispose the actuator in a passive or neutral failure mode. The passive-failure mode allows the actuator (15) to remain in the last-known valid position or move in response to an external force such as provided by a redundant backup actuator thereby avoiding a possibly dangerous flight condition that can result from a "hard over" actuator response to a failure condition.

Abstract: A valve assembly for controlling fluid flow between a fluid source and a load has an intake valve having a valve body displaceable between a closed position preventing flow through the intake valve and an open position permitting such flow and an output valve having a valve body displaceable between a closed position preventing flow through the output valve and an open position permitting such flow. Conduits or passages connect the valves in series between the load and the source so that fluid can only flow between the load and source when both of the valves are in their open positions. Respective biasing units urge each of the valves into one of its positions and respective electromagnet-type actuators are electrically energizable to move each valve into the other of its positions. The one position of one of the valves is the closed position and the one position of the other valve is the open position. In addition the two valves are substantially identical.

Abstract: The invention involves a new structure for a distributor for a hydraulic fluid utilization means, such as a single-acting jack, controlled by the distributor in any position. The distributor includes a spool-type valve and a hollow piston valve which is piloted by a needle valve. The needle valve and spool-type valve are both mechanically connected to a single mechanical lever.

Abstract: A vacuum control device comprises a casing in which are disposed at least two substantially parallel movable cups, the first cup being connected to the element to be displaced. Springs are interposed respectively between the two cups and between the second cup and a bottom end-wall of the casing. Two pipes or nipples connected to a vacuum source and to atmospheric pressure open into the casing respectively within the space located between the two cups and within the space located between the second cup and the casing end-wall.