Abstract: The valve is arranged to control the pressure of a hydraulic fluid by discharging a proportion of its flow, and comprises a mobile valve element arranged to control the opening of a discharge port of a first chamber and kept normally closed by the action of a spring, a piston element rigid with said valve element and arranged to define a second chamber which is in hydraulic communication with the first by way of a first bore of predetermined size, and a third chamber in hydraulic communication both with the preceding by way of a second bore also of predetermined size, and with the discharge outlet by way of a discharge port the opening of which is controlled by an interception member operated by an electromagnet; the pressure of said fluid is controlled by varying the discharge port controlled by said interception member and consequently the rate of a flow of control fluid passing through said first bore, second chamber, second bore and third chamber.

Abstract: A shutoff device for a fluid with a body having a conduit in which, in use, the fluid flows, a plunger arranged slidingly in a seat formed in the body and provided with an end portion suited to shut off said conduit, and means controlling the movement of the plunger into said seat. The control means comprise at least in particular a member having a hollow shape, made in piezoelectric material and arranged inside a chamber formed in the body and communicating with part of the surface of said plunger. Into the chamber is contained a liquid which is subjected to pressure changes as a consequence of the volume changes induced in the piezoelectric member; said liquid causes the movement of the plunger and consequently the shutoff of the conduit.

Abstract: A device for modifying and uniforming the distribution of the intensity of a power laser beam is provided wherein a rotatable support body includes three mirrors for reflecting an incident laser beam. The rotation of the mirrors with the support body effects a uniform distribution of the intensity of the incident laser beam resulting in a reflected laser beam having uniform distribution of intensity across its cross section. A modification section is included for modifying the amplitude of the reflected laser beam passing from the support body.

Abstract: An ultrasonic device for measuring the delivery of fluid through a conduit. A pair of electroacoustic transducers are arranged in the wall of the pipe forming the conduit in a mutually confronting relationship along an axis inclined relative to the conduit axis. Each transducer is able to convert an electric signal of predetermined frequency into an ultrasonic wave which propagates through the fluid toward the confronting transducer. After a predetermined interval of transmission, each transducer receives the transmitted wave and converts it to an electric signal. A collimator is disposed in the path of the fluid upstream of the transducers. An oscillator outputs electrical signals of predetermined frequency to the transducers.

Abstract: An epicyclic transmission with steplessly-variable speed control includes a set of three planet wheels (46) which are in the form of tapered rollers of dual conicity and are supported for rotation by a planet carrier (34) driven by a drive shaft (28). The tapered planet wheels have a larger frusto-conical portion (48) in rolling contact with a governing annulus (58) which is locked for rotation and is displaceable axially, and a smaller frusto-conical portion (50) associated with a driven annulus (92) which rotates a driven shaft (102). The tapered planet wheels also have two axially-spaced bearing surfaces (52,54) in rolling contact with two corresponding bearing surfaces (136,138) of a freely-rotatable sun wheel in the form of a sleeve (122) coaxial with the drive shaft (FIG. 1).

Abstract: The detection of surface defects in mechanical parts is effected by the analysis of diffracted light coming from these defects. The detection method includes the steps of illuminating the surface of the part to be examined with incoherent light and forming a flat image of the said surface in a transparent photosensitive layer of a spatial light modulator. The spatial distribution of the intensity of the incoherent light reflected by the said surface produces a corresponding and proportional spatial distribution of values of refractive index in the photosensitive layer. This layer is illuminated with plane polarized, coherent light by frame scanning in elementary areas. During the scanning operation, the variations in at least one of the polarization components of the coherent light are detected by a matrix of converters after the light has traversed the said transparent photosensitive medium.

Abstract: A workpiece to be treated, for example, an engine cylinder, is held vertically with a liquid-tight seal in a treatment device including a head which is fixed in the working plane of a work bench, and a counterhead supported from the work bench by a bracket which can be raised hydraulically. The device is selectively connectible, through control valves and circulation pumps, to reservoirs containing different treatment liquids. The liquids enter the cylinder in an ascending flow through the head in such a way as to avoid swirling movements. Preferably, several treatment devices are arranged to work in synchronism.

Abstract: The device comprises a plurality of superimposed sectional plates each of which is provided with aligned holes defining a plurality of ducts lying in side-by-side relation, each of the ducts containing a plurality of helically twisted vanes which are angularly displaced with respect to one another at angles of substantially 90.degree..

Abstract: An electrode tip for electric spot welding is formed with a hole which extends from one side of the tip to the end surface of the tip and is arranged to receive one end of a radiant energy conveyor which is intended to transmit a signal indicative of the temperature reached at the end surface of the tip. An insert is fitted within the hole with interference and arranged adjacent to the end surface of the tip in order to ensure the continuity of the said end surface.

Abstract: The distributor is designed to control the supply of a fluid under pressure into a chamber of a hydraulic actuator and the outlet of fluid from another chamber of said actuator, and comprises a first chamber and a second chamber, which are designed to be communicated with one of said chambers of the actuator, and a slide valve movable in the direction of its axis in a corresponding seat of the distributor; the distributor comprises means which respond to the pressure prevailing inside said first and second chambers of the distributor and means for choking the cross-section of the outlet for the fluid from said first and second chambers of the distributor, said pressure-responsive means being connected to said choking means so that, as a result of a movement of the movable member of said actuator at a velocity higher than a predetermined velocity, said choking means bring about a reduction in the velocity of said movable body.

Abstract: A power distribution system is provided which includes:a plurality of power outlets connected to the supply conductors of the system and enabling the connection of a corresponding plurality of electrical loads to the system; anda control unit connected by control conductors to the power outlets and arranged to monitor both the power suppliable by the system and the power required by the electrical loads for their operation.Each power outlet includes a switching arrangement with two operating states. In its first state, the switching arrangement enables a load connected to the power outlet to be measured by the control unit, this switching arrangement being thereafter switched into its second state by the said control unit to enable the load to be supplied with the power required for its operation only if this power does not exceed the yet-unused electric power capacity of the system.

Abstract: A transducer having six degrees of freedom is provided for converting forces and moments applied to a movable member, particularly to the movable arm of a robot, into electrical signals. The transducer includes a cylindrical body which is intended to be connected to the movable member and whose lateral surface has two axially spaced portions each provided with four equiangularly spaced metal plates. A cylindrical casing is resiliently supported about the body and provided on its inner surface with two substantially semi-cylindrical metal plates arranged facing the plates carried by the body in such a way as to define therewith a narrow interspace and to constitute eight capacitors. The capacitances of these capacitors depend on the relative positions of the plates of the casing and the plates of the body. The transducer also includes detectors connected to the plates of the body and of the casing.

Abstract: The characteristics of a gas-liquid heat exchanger are described, for particular use in the production of hot or superheated water by means of the exhaust gases emitted through the chimneys of a thermal treatment furnace, comprising an internal tubular element, for the passage of the gases, surrounded by an external tubular element which defines an annular chamber through which a liquid flows in counter-current to the flow of the gases in the internal tubular element. The latter is provided on its external surface and on its internal surface with radial fins, angularly equidistant from each other, extending axially for a substantial portion of the length of the internal tubular element.

Abstract: The regulator is designed to control the flow of a pressurized fluid between a source of said fluid which feeds it at a feed pressure, and a user device in which the fluid is at a utilization pressure which depends on the operating conditions of the device; the regulator also comprises a valve element mobile in the direction of its axis and arranged to vary the degree of closure of an orifice between a feed chamber and a utilization chamber, and a first and second cavity in which there is housed a first and second active surface respectively, on one of which there acts the utilization pressure and on the other of which there acts a control pressure arranged to control the movement of the valve element.

Abstract: An automatic timer valve for irrigation plant includes a tubular differential-area piston which defines respective major-diameter and minor-diameter chambers in a hollow valve body. The chambers normally communicate through the piston to allow water to flow interruptedly from an inlet to an outlet. A build-up of back-pressure at the outlet acts against the major face of the piston and, overcoming the inlet pressure, advances the piston against a spring to cause abutment of the shutter disc and an annular shoulder. This abutment cuts off the flow, with the exception of a restricted passage, and puts the outlet into communication with a drain outlet. When the pressure in the outlet drops, the higher relative pressure at the inlet displaces the piston in a reverse stroke and uninterrupted flow recommences.

Abstract: A feeler device for measuring the degree of roughness of an uneven surface being examined, the device comprising a transmitting transducer arranged to convert an electrical signal of a predetermined frequency into an ultrasonic wave propagated through a liquid coupling medium and having a wave length of the same order of magnitude as the uneven surface being examined, a generator being provided to generate and feed the electric signal to the transmitting transducer.

Abstract: A motor vehicle provided with servo-assisted controls for the brakes and steering, has an hydraulic system of the type comprising a volumetric pump the input of which is connected to a reservoir, and first and second distributor devices the first of which is associated with the steering control device and the second of which is associated with the master cylinder for control of the brakes. The said second distributor device is formed in such a way as to function also as a pressure modulating valve.

Abstract: A railway-vehicle truck has a support structure in the form of a horizontal rectangular plate the opposite ends of which carry respective transverse tubular supports. Each tubular support mounts a shaft the two ends of which carry respective arms. Each arm rotatably mounts a railway wheel. Between each shaft and its corresponding tubular support are provided bushes of elastomeric material which permit misalignment of the shaft and support as the vehicle traverses a bend. The horizontal plate of the support structure is formed with a rectangular aperture mounting a sliding block for sliding movement transversely of the truck, though limited play is also provided for longitudinally of the truck. A truck pivot pin extends vertically down from the vehicle body through a central hole in the sliding block. Upper and lower plate elements are carried by the pivot pin and serve to sandwich upper and lower annular elements of elastomeric material between themselves and the facing surfaces of the support structure.

Abstract: The device comprises a plurality of superimposable elements, in each of which there are formed cavities and holes arranged to originate channels for conveying the components, the said channels being disposed so as to originate a plurality of channel assemblies disposed in series to each other, each assembly comprising a first central channel, second channels with axes are substantially orthogonal to the axis of the said first channel, which second channels communicate with this latter and are disposed radially with respect to it, third channels, each of which has its axis parallel to that of the said first channel and originates from a corresponding second channel, and fourth channels whose axes are substantially orthogonal to the axis of the said first channels and which are disposed radially with respect to it.

Abstract: A railway carriage body comprises a shell structure formed from a base sub-assembly, a pair of side-and-roof sub-assemblies each of which constitute one side and part of the roof of the body, and a pair of end-wall units. The base and side-and-roof sub-assemblies when assembled together make up a series of transverse rectangular frames interconnected by longitudinal girders to which a sheet metal covering is fixed. Each frame includes a two-part lower transverse element forming part of the base sub-assembly, and a two-part upper transverse frame element the two component parts of which are included in respective ones of the side-and-roof sub-assemblies. The two frame parts making up each upper and lower transverse frame element are so fashioned as to permit them to be adjusted longitudinally of each other during assembly and prior to being rigidly connected together; as a result, the width of the carriage body can be set as required.