Abstract: A coupling has input and output members interconnected by two-link coupling elements which are flexible in the plane of rotation by centrifugal force acting on them as the coupling rotates and by the torque transmitted. The coupling is soft over a range of speeds and torques.The input member is constructed from two metal spinnings welded together to form a housing which supports the pivot of each coupling element at both ends. The output member is similarly constructed with bushes welded on to support the pivot also at both ends. The pivots are axially free within limits increasing the axial misalignment capability of the coupling. A spring arrangement to buffer the links if they rapidly approach their stops is provided.

Abstract: In a mechanical seal, a seal face member is compressed by a shrink fitted squeeze ring onto a spigot of a carrier forming one of two seal elements. This arrangement reduces distortion of the seal face and shrouds the seal member from attack by a fluid product in the space. Distortion of the seal face is further discouraged by also shrink fitting the squeeze ring onto the carrier. The squeeze ring circumferentially abuts the face seal member and either radially or circumferentially abuts the carrier to provide structural stability and to shroud the face seal member on three sides leaving only the seal face exposed. The squeeze ring can be arranged internally of the seal face member with the spigot on the carrier arranged externally. In either event the seal face member, usually constructed from carbon is held under radial compression for increased strength.

Abstract: A backup seal for a main seal (not shown) sealing a rotary shaft (10) to a housing (12) comprises a rotary seal element (20) sealed (22) to the shaft (10) and a stationary seal element (16) sealed (18) to the housing (12). The seal elements (16,20) have opposing annular seal surfaces (41,42) surrounding the shaft (10) and these are adapted to be urged together to form a running seal therebetween substantially only by the pressure of fluid product leaking through the main seal should that fail. A second aspect of the invention provides a close fit bush (50) which helps to close the seal faces (41,42) together when the main seal fails and before any leak occurs between them.

Abstract: A mechanical seal for a shaft (1) existing a housing (12) has an end plate (22) secured to the housing and a sleeve (26) secured to the shaft. The sleeve (26) carries a rotary seal element (40) and the end plate a stationary seal element (52) which form a running seal at faces (48,50). A multipurpose bush (60) is a close fit on the sleeve (26), it positions a spring (64) pressing the seal elements (40,52) together, it caries a lipseal (78) and it prevents collar (30) securing the sleeve (26) to the shaft (10) from contacting the end plate (22) in the event that the sleeve becomes unsecured from the shaft (110). The bush (60) is constructed from spark resistant material. A removable key (88) positions the sleeve (26), and hence the seal elements (40,52) and bush (60) with respect to the end plate (22) prior to tightening sleeve-security screws (32).