Abstract: A member (4) for a Venetian-blind action roller blind, comprises a bar (8, 8?, 8?) and a slat (9, 9?, 9?) which are connected together at a first hinge (7) in such a way as to be able to pivot, and which have respective outer hooks (5, 6; 5?, 6?; 5?, 6?), the outer hook (5, 5?, 5?) of the slat (9, 9?, 9?) being arranged to form, with the outer hook (6, 6?, 6?) of the bar (8, 8?, 8?) of an identical second member (4), a second hinge. The slat also carries two inner hooks (10, 11; 10?, 11?, 10?, 11?) curved in opposite respective directions of which the first (10, 10?, 10?) engages in a recess (15) in an inner hook (12, 12?, 12?) of the bar and the second (11, 11?, 11?) extends round an outer side of the inner hook (12, 12?, 12?) of the bar. The inner hooks (10, 11; 10?, 11?; 10?, 11?) of the slat (9, 9?, 9?) have arcuate, concentric surfaces whose common centre is an axis of pivot (27, 27?, 27?) of the first hinge (7).

Abstract: A combustion chamber structure for a rocket engine or the like, has a combustion chamber liner with cooling channels and at least one manifold for feeding and removing a coolant, particularly a cryogenic fuel. The at least one manifold is brazed together with the combustion chamber liner and the area of the combustion chamber liner that is not covered by the at least one manifold is coated with an electroplated structural jacket. The invention also includes a method for manufacturing the combustion chamber structure.

Abstract: A combustion chamber structure for a rocket engine or the like, has a combustion chamber liner with cooling channels and at least one manifold for feeding and removing a coolant, particularly a cryogenic fuel. The at least one manifold is brazed together with the combustion chamber liner and the area of the combustion chamber liner that is not covered by the at least one manifold is coated with an electroplated structural jacket. The invention also includes a method for manufacturing the combustion chamber structure.

Abstract: A combustion chamber for a rocket engine expels a hot stream of gas and has a cooling device. The inner wall of the combustion chamber adjoins the cooling device and contains depressions formed in such a way that the stable outer layer of the stream of gas that forms in the proximity of the inner wall of the combustion chamber during operation of the combustion chamber is destabilized in the area of the depressions.

Abstract: A combustion chamber for a rocket engine expels a hot stream of gas and has a cooling device. The inner wall of the combustion chamber adjoins the cooling device and contains depressions formed in such a way that the stable outer layer of the stream of gas that forms in the proximity of the inner wall of the combustion chamber during operation of the combustion chamber is destabilized in the area of the depressions.

Abstract: A method of producing a finely structured body which includes a plurality of stacked, cut sections of foil at least one of which is provided with grooves in a selected groove direction on at least one surface thereof, and which has a plurality of closely juxtaposed, channel-like perforations with high shape accuracy, true dimensions and high surface quality. The method includes: a. providing a vacuum clamping means comprised of a ground, sintered metal plate which is connected to a vacuum source and which is positioned on a work table which is movable in two mutually perpendicular directions X and Y; b. positioning a machinable foil on the ground, sintered metal plate and clamping the machinable foil thereto by applying an effective amount of vacuum; c.

Abstract: A method of producing a finely structured body comprised of a plurality of stacked, cut sections of foil at least one of which is provided with grooves. A machinable foil is wrapped around a cylindrical mandrel of a lathe to overlap opposing edges. The overlapped edges are clamped into an axial recess of the cylindrical mandrel by means of a clamping means and a plurality of grooves cut into the surface of the foil by means of at least one shaping diamond positioned in a feed which is finely adjustable. The plurality of grooves each have a groove length, a groove width, and a cross-sectional shape that is constant over the groove length and is freely selectable. Then, the grooved machinable foil is cut into cut sectoins and the cut sections are stacked. The plurality of grooves have a form precision such that, for groove lengths of more than 1000 .mu.m, the groove width has an accuracy of about .+-.1 .mu.m for land widths which equal or exceed about 15 .mu.m.

Abstract: Gas separation nozzles are produced by machining the nozzle parts, such as a holding body and separation elements by moving sectional material, for example, prefabricated sectional steel or aluminum alloy rods through a high precision sliding guide path past a shaving tool, whereby the workpiece is pressed against supporting and retaining surfaces of the guide path at least at three points and a shaving tool is applied to the moving workpiece in an area defined by said three points so that the tool is effective as close as possible to the pressure applying points or areas. At least two separation elements are supported in a dovetail groove of a holding body so that nozzle edges of the elements extend into a gas deflection groove in the holding body. Where four separation elements are held in a common dovetail groove of the holding body, two of the four elements are provided with a gas deflection groove extending along its respective nozzle edge.