Abstract: The pressure in a high-pressure steam boiler or other pressure fluid tank is occasionally relieved by means of a discharge device having a pressure-relief valve mounted on an ejection conduit opening into a hood connected to a discharge conduit. A break in continuity is provided between this ejection conduit and this hood in order to allow relative movements thereof under thermal expansion; furthermore the ejection conduit opens into the hood through a generally transversely directed nozzle system so that the jet issuing therefrom has a zero or negligible axial velocity component.

Abstract: A vehicle riding on air cushions in which the lift of a platform is ensured by an arrangement of flexible skirts defining a central air-lift area at substantially constant pressure and a partitioned peripheral air-lift area. A closed loop of adjacent tubular skirts is inserted between the central and peripheral air-lift areas to increase the flying stability of the vehicle.

Abstract: A tunnel-furnace is cooled by circulating air between two metal walls forming a jacket and is provided with a ported or permeable hearth extending along its entire length. The articles to be heated or baked in the furnace are supported therein on an air cushion formed with the heated air providing from the cooling jacket and supplied through the ported hearth.

Abstract: In order to transfer long vehicles upon a ground surface and more particularly railway carriages or wagons, use is made of platforms which glide over the ground by means of fluid cushions and which carry track sections for receiving vehicle wheels. Two or more such platforms which are movable independently of each other, are mutually positioned so that the respective track sections are in extension of each other and are assigned to the vehicle front wheel system and to the vehicle rear wheel system respectively, each platform being independently lockable with the vehicle.

Abstract: An air-lift vehicle has inner and outer multi-lobed peripheral skirts arranged so that the corresponding lobes of the skirts are in register. Means is provided to supply compressed air to the inside of the inner skirt and between the inner and outer skirts for lifting purposes. The space between the skirts comprises a plurality of compartments each defined by two corresponding lobes of the inner and outer skirts. The lower edges of the lobes of the outer skirt at least are located in the same horizontal plane as a result of which the height of lift and the stability of the vehicle are improved.

Abstract: An arrangement for mounting a cascade of guide vanes or other objects extending across a conduit, characterized in that there is provided within the conduit two longitudinal partitions or plates separated by a small gap, and in that said object is formed in two parts each of which has one end fixed to a wall of the conduit and the other to the longitudinal plate nearest to this fixing point.

Abstract: The invention relates to a band pressing shoe. Such shoe includes a rigid body to which is attached a thin flexible and inextensible strip. When the rigid body is subjected to a pressing thrust, the strip assumes an arcuate shape and tautens. Between the strip and the band are interposed one or more fluid cushions supplied from a manifold through an elastic mattress made of a cellular material. The pressing shoe can be supplied in all cases where it is required to drive or restrain a band running over a cylinder (e.g. a roller, drum, pulley or the like), examples being conveyor belts, transmission belts, metal strips undergoing splitting, planing or coiling, and so forth.

Abstract: Letters or like thin articles moving flat over a horizontal conveyor track are to be switched selectively towards either track of a fork. Such switching is controlled by intermittent pneumatically operating actuator means acting in the region of a gap in the track at the end of an incoming section, in order to deflect the articles away from their horizontal path and downwardly, these means cooperating with a physical surface which is inclined relatively to this path and towards which the articles are swung under the pneumatic action. This surface is composed of a stationary plate having a slanting operative face exposed to said pneumatically operating actuator means.The device is useful for the automatic postal sorting of letters.

Abstract: The invention has to do with a system designed to support and/or guide a ground effect machine (1) along a supporting surface (2).This system consists of structure (4) carrying a load (F), a floating partition (5) holding the cushion (9) and a flexible partition (10) defining laterally between the structure (4) and the partition (5) an enclosure of suspension (13) having a variable volume which is connected with the cushion (9) through calibrated orifices (6). The enclosure of suspension (13) has a convergent-divergent configuration, for example biconic. The area of the base (S), the area (S.sub.o) at the level of the collar (15) and the angle (.theta.) of the enclosure (13) are predetermined and remain constant.

Abstract: In and for an installation comprising a fluid source and a plurality of fluid-using receivers to be fed with fluid from said source, a device for supplying fluid from said source to said receivers independently of one another, said device comprising a fluid manifold connected with said fluid source and branching out into a plurality of fluid emission nozzles having each an outlet opening, and a plurality of fluid-receiving pipes each of which is connected with a corresponding receiver and has an inlet opening located in line with and spaced by a gap from the outlet opening of a corresponding emission nozzle, the cross-sectional area of said inlet opening of a receiving pipe being at the very most equal to the cross-sectional area of said outlet opening of said corresponding emission nozzle.