Abstract: A coil-shaped body is used to transmit torque between shafts spaced axially apart and with the shaft axes disposed angularly to one another. Such an arrangement is used in a bent steering column for a safety steering mechanism. The coil-shaped body is formed by winding a plastics material impregnated fiber strand around an axially extending mandrel so that the layers of the strand are in crossing relation. The crossing superposed layers form lattice bars between the crossover points of the body. The lattice rods have a radial dimension greater than the length of the strands. The angle of the lattice rods relative to the axis of the coil-shaped body is greater than 55.degree..

Abstract: A connecting rod assembly includes an axially elongated member with openi spaced apart in the axial direction. The axis of the openings extend perpendicularly to the axis of the member. A connecting rod shaft extends in the axial direction of the member between the two openings. A fiber reinforced plastics material belt extends around the first and second openings and also around the connecting rod shaft. Oblique cuts are formed in the belt on opposite sides of the connecting rod shaft adjacent one of the openings. A highly heat-resistant adhesive is placed in the oblique cuts for splicing the belt together.

Abstract: A coupling or clutch type element for connecting a driving member to a drn member, in a universal manner allowing for axial and/or angular displacements between the two members, is made by laminating sheets cut from preimpregnated fiber compound webbings onto a subsequently removable core. The sheets are placed in consecutive, overlapping layers with a predetermined fiber orientation. The initial tackiness holds the blanks and layers of sheets together. The assembly of laminates is less compressed in a mold and cured which provides the required bonding and operational strength. After removing the coupling element from the mold the core is removed, for example, by melting or washing. The resulting product does not require any subsequent machining.

Abstract: The wings of a hingeless helicopter rotor are secured to the head of the rotor by connecting elements of fiber compound materials. Each connecting element has at least two outer layers of fiber compound materials and an intermediate layer of .+-..beta.-fiber compound materials between the outer layers. The intermediate layer is bonded to the outer layers by a suitable adhesive. The intermediate layer takes up the central portion of the securing flange of the rotor head and its axial thickness increases radially inwardly. The intermediate layer has four side lobes which extend laterally out of the confines of the outer layers. These side lobes are connected by bolts to the rotor head. This structure provides a strong connection in which the outer layers are not weakened. Effects of the lead-lag movement of the rotor wings and of any torsion of the connecting elements are minimized and the fictitious hinges are located close to the rotational axis even within the zone defined by the rotor head flange.

Abstract: A drive shaft including a universal coupling is made in the form of a uniy bonded fiber material structure having anisotropic properties. A winding form or mold is assembled to include, for example, an elongated winding sleeve, a flange forming core element, and an elongated winding mandrel joined together. Impregnated fiber material is wound onto the mold so that the fibers of the winding lie at thread angles approximately .+-.45.degree. with respect to the longitudinal axis of the form or mold. The wound structure is compressed whereby the coupling assumes its intended shape after curing or hardening. Portions of the form or mold are removed, for example, by dissolving and washing in a suitable solvent. Alternatively the drive shaft coupling is formed directly on the torque transmitting shafts to be coupled so that the transmitting shafts are integrated into the unitary structure. The annular flange and 45.degree.

Abstract: Windings of fiber compound materials are produced on a core in multicourses hereby the fiber arrangement may change from course to course. For this purpose a plurality of fiber coil carriers are arranged in sequence one after the other as viewed in the direction of core advancement. The fiber coil carriers are arranged coaxially relative to the core. The coils of fibers are supported by the fiber coil carriers. The r.p.m. of each fiber coil carrier is adjustable independently of the r.p.m. of any other coil carrier. Each r.p.m. is adjusted to be inversely proportional to the desired pitch of the fibers in the respective winding course. The direction of rotation of each coil carrier is also selectable independently of the rotational direction of any other coil carrier.

Abstract: The present hingeless rotor system for helicopters has carrier spars or b each of which is subdivided into three functional sections substantially forming the blade neck connecting the lift producing portion of the respective rotor blade to the rotor mast. The carrier spar sections form a single structural blade neck member extending for about two tenths of the rotor radius from the rotor mast to the lift producing blade portions. About one half of the length of the blade neck adjacent to the rotor mast form the connecting zone proper. The spar sections comprise bands forming respective loops in the connecting zone proper. Two of the band loops are connected one above the other and a third band loop is displaced in the direction of rotation of the rotor from the first mentioned band loops. The third band loop is releasably connected to the rotor mast to allow a folding of the respective rotor blade. The spar sections are interconnected by shear resistant bridging webs having a T- or X cross-section.

Abstract: A rotor blade formed of a fiber-reinforced plastic material is constructed for the absorption of at least one of longitudinal forces and bending forces. The interior of the blade is formed of an elongated bundle of fiber strands forming a loop intermediate its ends. The loop defines one end of the longitudinally extending blade. The bundle has two limb portions extending from the loop and forming, adjacent the loop, a transition portion followed by a neck portion and then a blade portion. A skin encloses the blade outwardly from the loop. A layer of fiber strands extends around the outer surface of the loop and between the skin and the limb portions at least in the transition portion. In the region of the loop the fiber strands extend in parallel relation with the fiber strands in the bundle, however, in the transition portion the fiber strands in the layer extend angularly across the longitudinal axis of the blade.

Abstract: A loop type force transmitting element is made of fiber composite or compd material. The force transmitting element has a predetermined cross-sectional shape and is open at one end. The cross-sectional area through the loop is constant along the length of the loop. However, the cross-sectional shape or configuration varies along the length of the loop. This type of structure is accomplished by machine winding the reinforcing fibers or filaments as an endless loop onto a winding core which has lateral walls spaced from each other so that the spacing corresponds to the wall thickness configuration along the length of the force transmitting element. One loop portion of the initially endless loop is severed after the composite material has been hardened whereby a loop element is formed which is open at one end.

Abstract: Shear transfer elements can be formed by winding or weaving unidirectional fibers on a support structure. In a winding operation the support structure consists of two intersecting planes of winding mandrels with the planes arranged in angularly spaced relation. Each plane has two pair of mandrels with the mandrels in each pair located on the opposite sides of the line of intersection between the two planes. After the fibers are wound on the mandrels, each mandrel is axially disposed in the opposite direction relative to the other mandrel in the pair and also to the adjacent mandrel in the other pair in the same plane. Next, the fibers are pressed to form the shear transfer element. In a weaving operation, the support structure consists of a pair of pivotally interconnected frames. The fibers are woven onto holders on the sides of each frame extending parallel to the pivot axis of the frames.

Abstract: Laminated sectional girders having webs and flanges may be formed to incre the shear stresses thereof by including as a structural part of the girder at least one connecting layer extending through both the flanges and webs of the girder and made of prefabricated sections with additional girder layers being arranged adjacent the sections of the connecting layer. The additional adjacent layers may comprise both fiber-reinforced material layers forming the laminated flanges of the girder as well as the webs thereof. The additional layers may be arranged either between prefabricated sections of the connecting layer or they may be arranged outside of the prefabricated sections.

Abstract: In forming a connecting element for use in introducing forces into a strural part, a continuous roving is removed from a source of supply, impregnated with a synthetic resin, and guided over a rotatable disk. Extending outwardly from each of the opposing faces of the disk is a removable bush. The roving is wound in layers on each face of the disk in an alternating manner. During the winding operation, as the disk rotates, the roving is secured in a recess on the circumferential periphery of the disk then it moves across one face of the disk into contact with the bush on that face and finally is secured in another recess spaced angularly from the previous recess. At this time the roving is displaced in the axial direction of the bushes toward the other face of the disk and the winding operation is repeated on the other face. By repeating these operations a multiple number of layers are displaced on each face of the disk.

Abstract: An elastomeric damping arrangement is constructed to provide a highly efficient damping of the vibrations of a vibration prone member, such as an airfoil, especially a helicopter rotor blade. The damping arrangement is applied directly on or to the vibration prone structural member in the region of dynamic deformation, as an integral component part of the structural member. At least one damping layer is covered by a protecting layer which merges smoothly into the surface of the vibration prone member. The damping layer is made of a viscoelastic material having a high internal damping action. The protecting or cover layer is made of high strength material having a high rigidity in the direction of the occurring damping force.

Abstract: In finishing the construction of a rotary wing, particularly helicopter rotor blade, the blade is weighed to determine the position of its static moment. The measured value is compared with a predetermined value and, if necessary, the static moment is adjusted by applying a high specific gravity filler material to the surface of the blade. The filler material has a specific gravity in a range of 6 to 10 p/cm.sup.3 and can be formed of a mixture of tungsten powder and epoxy resin. The weighing operation is performed on a three scale apparatus with one scale supporting the end of the blade attached to the rotor and the other two scales supporting the opposite end of the blade.

Abstract: One of two races of a roller bearing is equipped with a sliding ring exteng thereabout, with a melting ring formed of material having a melting point higher than the normal operating temperature of the bearing being interposed between the one race and the sliding ring. Malfunction of the bearing such as might occur by seizure of the bearing rollers will cause at least partial melting of the melting ring whereupon the one race is placed in relative sliding engagement through the melting ring with the sliding ring.