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 prosthesis for knees and other joints comprises two portions which are disposed side by side and which are at least partially spaced apart from one another. Each portion of the prosthesis includes a pair of spaced apart, relatively inextensible primary components. Disposed between and spaced from the primary components in each portion of the prosthesis is a pivot member. Each pivot member is resiliently secured to the two corresponding primary components of its portion of the prosthesis so as to permit and accommodate relative rotation between the pivot member and the primary components. As a result, the two primary components of each portion of the joint prosthesis can rotate toward and away from one another about an axis that is disposed at least adjacent to and at least approximately parallel to a central axis of the corresponding pivot member. The pivot member and the primary components of each portion of the prosthesis are preferably secured together by one or more bodies of elastomer.

Abstract: A joint prosthesis comprises two relatively inextensible primary components that are spaced apart from one another. Disposed between and spaced from both of the components is a pivot member. The pivot member is resiliently secured to each of the primary components so as to permit relative rotation between the primary components and the pivot member. As a result, the two primary components of the prosthesis can rotate toward and away from each other about an axis that is disposed at least adjacent to and at least approximately parallel to a central longitudinal axis of the pivot member. The pivot member and the primary components of the prosthesis are preferably secured together by one or more bodies of elastomer.

Abstract: A joint prosthesis comprises two relatively inextensible primary components that are spaced apart from one another. Disposed between and spaced from each of the primary components is a pivot member that is also fabricated of relatively inextensible material. When viewed in section taken normal to its central longitudinal axis, the pivot member has two discrete arcuate surfaces that are spaced apart from one another about the circumference of the pivot member. One of the primary components of the prosthesis is resiliently secured to one of the arcuate surfaces of the pivot member, while the other primary component of the prosthesis is resiliently secured to the other arcuate surface of the pivot member. The resilient connections between the pivot member and the primary components permit relative rotation between the pivot member and each of the primary components.

Abstract: A rotary energy storage device includes a core in which a multiplicity of anisotropic filaments are embedded in a resin matrix. Extending through the core is an axis about which the core is rotatable. At least a portion of the filaments in the core are oriented transversely of each other, but not circumferentially of the axis of rotation. The transverse orientation of the filaments relative to each other produces resistance along at least two axes to radial and tangential stresses imposed on the core when it is rotated. The outer peripheral surface of the core is enclosed and snugly fitted by a shell. The shell includes a filamentary structure that provides a plurality of substantially parallel and juxtaposed filament portions oriented to circumscribe the peripheral surface of the core. The filament portions of the shell are encased in a matrix material that bonds adjacent filament portions to one another.

Abstract: A flexible drive coupling for innerconnecting a pair of rotatable shafts includes a hub and an outer member. The outer member has formed in it a central opening and is disposed so as to circumscribe the hub and to be generally concentric with the central axis of the hub. Secured to and disposed between the hub and the outer member is a flexing section. The flexing section includes a plurality of helically wound, radially alternating layers of a resilient material and a substantially inextensible material. The layers of the flexing section, when viewed in section taken transversely through the layers and generally parallel to the central axis of the hub, have widths that diminish with increasing radial distance from the hub. The widths of successive resilient layers, however, diminish with increasing radial distance from the hub at a faster rate than the widths of successive and intervening inextensible layers.

Abstract: An adjustable support system mounts one member, such as a textile spindle, on a second member, such as a textile machine rail, so as to reduce the transmission of vibrations between the two members. The support system incorporates a flange to which is secured an elastomeric element for resiliently mounting the textile spindle relative to the flange. The flange is kept spaced apart from the machine rail by a member or members that at least contact the flange and at least contact the machine rail. The spacing between the flange and the machine rail can be adjusted through manipulation of adjusting screws or bolts in such a manner as to change the orientation of the flange and the textile spindle mounted on the flange relative to the machine rail. Like the spacing member, the adjusting elements contact both the flange and the machine rail.

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 rotary energy storage device comprises a rotor and a hub for mounting the rotor on a shaft. The rotor is joined to the hub by an interlayer disposed between the rotor and hub. One surface of the interlayer is bonded to a mounting surface of the hub. A second surface of the interlayer, which is opposite the first surface, is bonded to a surface of the rotor which is opposite and spaced from the mounting surface of the hub. Due to differences in their constructions, such as their relative dimensions, the rotor and the hub experience different strains due to the centrifugal forces exerted during rotation of the energy storage device. The difference between the strain at the mounting surface of the hub and the strain at the opposed surface of the rotor induces a shear stress in the interlayer. To accommodate the induced shear stress, the interlayer has a thickness and a shear modulus which permit the interlayer to deflect in response to the difference in strains without structural or bond failure.

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 rotor blade retention system connects an elongated rotor blade to a rotor hub that is rotatable about its central axis. The connected rotor blade normally extends generally radially from the hub and is rotatable with the hub. The retention system includes a pair of bearings that are interconnected in parallel load transmitting relationship. Both bearings are connected in serial load transmitting relationship with a flap hinge. One bearing is relatively stiff along the longitudinal axis of the rotor blade and is less stiff in directions transverse to the longitudinal blade axis. The other bearing is most stiff in directions transverse to the rotor blade axis and is less stiff along the axis. Both bearings define effective elastic centers which are located along the longitudinal blade axis, but the two elastic centers are spaced from each other. The two bearings accommodate lead-lag motions of the rotor blade.

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 adjacent each end an annular flange that extends radially inwardly relative to the housing. Disposed between the flanges of the housing is an annular flange which extends radially outwardly adjacent one end of the tubular member. The other end of the tubular member projects through an opening at one end of the housing for attachment to a fluid conduit. Within the housing and encircling the tubular member is a rigid annulus. On each side of the rigid annulus is an annular flexible element that encircles the tubular member and includes at least one body of elastomer. The flexible elements are joined to the rigid annulus and to adjacent flanges of the tubular member and the housing so as to define a fluid-tight seal and load bearing connection between the tubular member and the housing.

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: A laminated bearing comprises a plurality of alternating and bonded together layers of elastomeric material and substantially nonextensible material. Each of the layers is a frustroconically shaped annulus that has a pair of frustroconically shaped side surfaces and is concentrically disposed about a common axis extending lengthwise of the bearing. The side surfaces of adjacent layers are bonded to each other such that the larger diameter end of each layer is disposed adjacent to the larger diameter end of another layer. Together, the larger diameter ends of the layers define an annular surface of the bearing. The annular surface formed by the ends of the layers defines, in radial section, an angle with respect to a line which lies normal to the side surfaces of the layers. The direction of the angle or inclination, with respect to the normal line, is toward the smaller diameter ends of the layers with increasing distance along the normal line away from the common axis. Preferably, the angle is about 9.

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.