| 摘要 |
A tilting pad journal bearing, which may be a back-up bearing for a magnetically suspended shaft capable of applying shock loads thereto, comprises in a first embodiment (20, Fig 1) an annular housing (24) for an array of arcuate bearing pads (30i) resiliently mounted by spring means (70) which biases the pads against heads (52i) of restraining bosses (50i) that limit radial displacement and cause the bearing pads to define a shaft space . The pads have associated therewith support pegs (60) secured to housing or p ad at one end and movable relative to the pad or housing at the other, and the spring means comprises stacks of individually deflectable elements mounted between relatively moving pad, housing or peg and pre-loaded by adjusting th e effective gap with the pads against the bosses. The spring means is compactl y formed by dished annular spring washers (72) mounted on the support pegs, relative movement between the springs during stack deflection also providing friction damping for the resilient suspension, being readily tuned by variation of number and stiffness of the spring washers. A second embodiment (120, Fig 5) employs stacks of circumferentially extending springs (172), th e springs of each stack being radially and circumferentially off-set from each other and each contributingto the support of a number of adjacent bearing pads (130i). Each spring (172c) is centrally mounted on a Spigot (1602) associated with one pad (1302) and secured at their ends to circumferentiall y spaced pads (1301, 1303). The circumferential extent of each spring is preferably .plusmn.90" so that when displaced radially on the spigot by the pad central to it, the en ds displace their secured pad ends with respect to tapered restraining boss heads (152) and tilt towards the shaft space to mak e damping contact with the shaft in quadrature with the shaft load displacing the central pad. Also, relative movement between such nested springs provide friction damping. Furthermore, the restraining bosses may be displaceable together to eliminate the shaft space clearance if the magnetic suspension fails or shows signs of failing. |
