Abstract: A flexible joint assembly for interconnecting two conduits that transport fluid under pressure includes an annular housing and a tubular member of smaller diameter than the housing. The housing has an opening at each end, as well as two spaced apart, annular flanges that extend radially inwardly with respect to the housing. The tubular member has adjacent one end a flange which extends radially outwardly and which is disposed between the two flanges of the housing. The other end of the tubular member projects from an opening at one end of the housing for attachment to a fluid conduit. Between each housing flange and the flange of the tubular member is an annular flexible element that includes at least one body of elastomer. One side of one of the flexible elements is exposed to the pressurized fluid flowing through the conduits and the joint, while one side of the other flexible element is exposed to the exterior of the joint.

Abstract: A flexible joint for a conduit transporting fluid under pressure includes a pair of spaced rigid rings. An annular flexible element is disposed between and sealingly engaging the rings so as to define a pair of annular exposed side surfaces on the element. One side surface is exposed to pressurized fluid flowing through the conduit, thereby creating a pressure differential across the flexible element between its side surfaces. To resist the load that results from the pressure differential, the flexible element incorporates a body of elastomer that has a thickness between the rings which decreases from the one side surface of the element to the other side surface. The flexible element can thus resiliently accommodate relative motion between the rings, while providing a fluid-tight, pressure-resistant seal.

Abstract: A muffler incorporates a tubular shell that has an acoustically reflective interior circumferential surface. In successive sections taken transversely through the shell, the acoustically reflective surface has at least a portion of its circumference shaped to define at least part of an ellipse or a parabola. Between an inlet into and an outlet from the shell, a fluid flow path extends along an axis lengthwise through the shell. A sound absorptive treatment is disposed along a second axis extending lengthwise through the shell. The treatment is spaced from but communicates with the fluid flow path. At least one of the two axes is defined by corresponding focal points of successive transverse sections taken through the curvilinear portion of the circumference of the acoustically reflective shell surface. In operation, sound emitted from fluid flowing along the fluid flow path is reflected by the reflective shell surface to the sound absorptive treatment.

Abstract: An electric motor includes a motor frame and a fan driven by the motor disposed adjacent one end of and inside the motor frame. The fan draws air in through an inlet opening formed in the motor frame at the end of the frame opposite the fan. The air flows over and cools internal components of the motor and is exhausted by the fan in a radially outward direction through an outlet opening in the motor frame. A silencer for the motor includes an acoustical panel which at least partially surrounds the motor frame, is spaced from the frame, and is disposed to intercept air flowing radially from the outlet opening in the frame. The acoustical panel extends from the fan end of the motor frame partway along the length of the frame so as to direct air exhausted from the fan along the frame between the frame and the panel. The panel includes a layer of air-permeable sound absorbing material and air-impermeable sheet disposed adjacent to the sound absorbing material on the side of the material opposite the motor frame.

Abstract: A plurality of parallel and laterally spaced impermeable walls define an array of side-by-side elongate fluid filled cavities. Adjacent open ends of the cavities provide a sound-receiving or admittance end for the sound waves into the cavities. An acoustically reflective, preferably impermeable, barrier is disposed adjacent the ends of the cavities remote from their sound-receiving end and terminates the cavities. The cavities are uniquely configured to provide an effective geometrical sound absorbing structure while minimizing the structural elements required and, thus, the cost of manufacture.

Abstract: A rotary blade retention system comprises a rotor hub rotatable about a central axis and a retention assembly coupling at least one blade to the rotor hub. The blade extends generally radially from the hub and rotates with the hub about its central axis. The retention assembly includes a frictionless thrust bearing and an elastomeric thrust bearing connected together in series. The two bearings are mounted relative to the blade and the rotor hub such that when a centrifugal load is imposed on the blade, the bearings are loaded in compression and cooperate to restrain the blade against the centrifugal load. The frictionless bearing permits free pivotal movement of the blade about its longitudinal axis so as to effect variations in the pitch of the blade. The elastomeric thrust bearing includes at least one laminated bearing having a plurality of layers of rigid and elastomeric material which alternate lengthwise of the blade.

Abstract: A laminated bearing comprises a plurality of alternating and bonded together annular layers of elastomeric material and non-extensible material. The layers alternate along a common axis extending lengthwise of the bearing so that the bearing can support substantial compressive loads applied generally normal to the layers. The layers include at least one elastomeric layer which, if formed to have a nominally constant modulus of elasticity throughout and if subjected to a compressive load, would experience a shear strain adjacent one of its inner and outer circumferences greater than the shear strain adjacent the other circumference. Such a difference in compression-induced shear strains would tend to cause uneven wearing of and a reduced service life for the elastomeric layer in question and for the bearing as a whole. To avoid or minimize uneven wear, the elastomeric layer is formed to have at least two different moduli of elasticity.

Abstract: A drive coupling for interconnecting a pair of rotatable shafts includes a rigid spider that has four coplanar arms. Adjacent arms of the spider are oriented generally perpendicular to each other. A rigid element is disposed between each pair of adjacent arms of the spider. A body of elastomer is secured between each rigid element and each adjacent arm of the spider. One pair of diametrically opposed rigid elements can be connected to one of the rotatable shafts. The other pair of diametrically opposed rigid elements can be connected to the other rotatable shaft. When torque is being transmitted through the coupling, the bodies of elastomer are loaded primarily in compression. Angular misalignment of the shafts is accommodated primarily by shear deflection of the bodies of elastomer.

Abstract: A laminated bearing comprises a plurality of alternating and bonded layers of elastomeric material and nonextensible material. The layers alternate along a common axis extending lengthwise of the bearing so that the bearing can support substantial compressive loads applied generally normal to the layers. Each layer is contoured to have, in section taken radially of the common axis, a portion projecting longitudinally toward one end of the bearing. Under large compressive loads, the contour of the layers may contribute to excessive strains in the elastomeric layers adjacent the end of the bearing toward which the layers project. To accommodate the compressive stresses without excessive strains, the layers of elastomeric material in a central lengthwise portion of the bearing have smaller compression moduli than the layers of elastomeric material adjacent the one end of the bearing.

Abstract: A compression mounting comprises a body of elastomer and a pair of load-transmitting devices that engage and cover two opposed and spaced apart surfaces of the elastomeric body. The two load-transmitting devices are disposed and configured to expose a circumferential surface of the body of elastomer. At least a circumferential portion of the surfaces so exposed is completely covered and enclosed by a shell or housing. The shell includes a filamentary structure that provides a plurality of substantially parallel and juxtaposed filament portions oriented to circumscribe the surface of the elastomeric body. The filament portions are less extensible than the elastomer of the elastomeric body. A matrix material encases the filament portions and flexibly bonds adjacent filament portions to one another. The shell snugly fits the surface of the elastomeric body and is more resistant to circumferential expansion than the elastomeric body.

Abstract: A propeller assembly comprises a rotatable drive shaft and two separate blade subassemblies resiliently coupled to and driven by the shaft. Each blade subassembly has a pair of interconnected propeller blades extending in opposite directions radially of the shaft. The blade subassemblies are disposed in parallel planes with the blades of one subassembly oriented transversely of the blades of the other subassembly. Rotational movement of the shaft is transmitted to the blade subassemblies through viscoelastic material which is torsionally loaded and stressed in shear. The viscoelastic material resiliently permits and damps in plane or lead-lag movement of each blade subassembly relative to the drive shaft. The subassemblies are also interconnected so that the viscoelastic material resiliently permits and damps relative in-plane movement between the subassemblies.

Abstract: A modular cushioning pad comprises a rigid plate and at least one elastomeric cushion centered on the plate. One end surface of the cushion is bonded to the plate, while the second, opposite end surface is spaced from the plate. The outer side surface of the cushion has a first portion that slopes outwardly and away from the end of the cushion bonded to the plate. A second portion of the outer side surface slopes inwardly and away from the first portion of the surface to merge with the second end surface of the cushion. The plate and cushion are preferably annular.

Abstract: A unitary resilient elastomeric pad is positioned between the bearing adapter and side frame of a railway truck. The truck side frame includes downwardly depending pedestal jaws spaced fore and aft of a bearing carried by the axle and defines longitudinally a semi-cylindrical load carrying surface between the jaws. Transversely, the load carrying surface is chevron shaped. A bearing adapter is carried by the bearing and defines a load receiving surface in opposed relation to the load carrying surface for matingly receiving same. The elastomeric pad is disposed in compression load carrying relation between the load carrying and load receiving surfaces and conforms to and bears against these surfaces.

Abstract: An elongate body of elastomeric material of substantially uniform width and thickness has support plates fixedly attached to opposite ends of the body of elastomeric material. The plates are oriented substantially parallel to each other and normal to the longitudinal axis of the body of elastomeric material. A rigid wedge member is mounted within and transversely of the body of elastomeric material between and in spaced relation to the plates. The wedge member forms a wedge angle in the body of elastomeric material for controlling the direction of buckling.

Abstract: A noise and vibration attenuating mounting for a textile spindle assembly includes a rigid inner member having an elongate sleeve adapted for attachment to the spindle assembly and a support ring carried by and extending radially from the sleeve. An elastomeric annulus includes portions secured to opposite radial faces of the support ring, preferably in radially spaced relation to the sleeve. A rigid washer is secured along a first free radial face of the annulus in radially spaced relation to the sleeve. A cylindrical casing portion of a holder concentrically surrounds the annulus and support ring in radially spaced relation to the support ring. The holder includes a radially inwardly extending clamping flange secured to the other free radial face of the annulus in radially spaced relation to the sleeve. At least a portion of the washer extends axially beyond the holder.