Split-nut blade locking assembly

{
  "publication_number": "US3721506A",
  "country": "US",
  "kind": "A",
  "title": "Split-nut blade locking assembly",
  "abstract": "A split-nut blade locking assembly, for maintaining the circumferential integrity of blades peripherally disposed within a groove around a rotor element includes a split-nut within which a set screw may be threadably engaged for spreading apart the halves of the split-nut and maintaining the halves in engagement with the side walls of the groove.",
  "claims": [
    "1. A split-nut locking assembly for attachment to a groove comprising: a wrenching set screw having an external thread around the body thereof; and a split-nut including a split-collar having two arcuate segments, the inside surfaces of which are threaded for threadably engaging the set screw, and wherein the arcuate segments of the split-collar integrally connect to flange members having sides which extend outwardly into shoulders adapted for engagement with the sidewalls of the groove when the set screw is threadably engaged within the split-nut so as to spread apart the halves of the split-nut.",
    "2. A split-nut locking assembly for locking a plurality of circumferentially spaced blades disposed about the outer periphery of a grooved rotor disc comprising: a wrenching set screw having an external thread around the body thereof; and a split-nut including a split-collar having two arcuate segments, the inside surfaces of which are threaded for threadably engaging the set screw, and wherein the arcuate segments of the split-collar integrally connect to flange members having sides which extend outwardly into shoulders adapted for engagement with the sidewalls of the groove when the set screw is threadably engaged within the split-nut so as to spread apart the halves of the split-nut.",
    "3. The assembly of claim 2 wherein: the side walls of the groove are undercut to provide inwardly directed abutment faces for engaging the outwardly extending shoulders of the split-nut and including at least one circular entrance slot through the inwardly directed abutment faces of the groove to accommodate insertion of the flange members of the split-nut within the groove, and each blade has a vane section extending outward from the periphery of the rotor disc and a root portion extending in a substantially inward radial direction from the periphery of the rotor disc, with each root thickened at the inner radial end to provide outwardly extending shoulders which abut the inwardly directed faces of the groove so as to radially and axially retain the blades with circumferential retention of the blades along the peripheral groove maintained by the split-nut, the outwardly extending shoulders of which also engage the inwardly directed faces of the groove upon threadable engagement of the set screw within the split-nut.",
    "4. The assembly of claim 3 wherein each blade includes an overhanging platform disposed between the vane and root portion such that the blades may be circumferentially arranged around the peripheral groove in platform abutting relation and wherein the platforms of the two blades adjacent the split-nut are indented to accommodate insertion of the split-nut while maintaining a minimum arc distance between the blades adjacent to the split-nut.",
    "5. The assembly of claim 3 wherein the set screw and split-nut include double lead threads to allow interchange between the halves of the split-nut.",
    "6. The assembly of claim 3 wherein: each blade root portion includes a pair of opposing transverse faces extending across the dovetail groove, and wherein each flange member of an arcuate segment of the split-collar includes an outwardly extending shoulder for engagement with a face of the groove and the respective ends of both flanges cooperate together to form split transverse faces such that circumferential sliding of the split-nut and set screw around the peripheral groove of the rotor disc is inhibited by abutment between the outside surface of the split collar with the inside surface of the circular entrance slot, circumferential sliding of the blades around the peripheral groove of the rotor disc is inhibited by abutment between the split transverse faces of the split-nut and the respective transverse faces of the blade root portions and outward radial withdrawal of the split-nut is prohibited by engagement of the outwardly extending shoulders with the inwardly directed abutment faces of the peripheral groove.",
    "7. The assembly of claim 3 wherein each blade root portion includes a pair of opposing transverse faces extending across the dovetail groove, and wherein each flange member of an arcuate segment of the split-collar includes a pair of oppositely extending shoulders for engagement with the opposing faces of the groove and the end of each flange terminates in a transverse face, wherein circumferential sliding of the split-nut and set screw around the peripheral groove of the rotor disc is inhibited by abutment between the outside surface of the split-collar with the inside surface of the circular entrance slot, circumferential sliding of the blades around the peripheral groove of the rotor disc is inhibited by abutment between the transverse faces of the split-nut and the respective transverse faces of the blade root portions and outward radial withdrawal of the split-nut is prohibited by engagement of the outwardly extending shoulders with the inwardly directed abutment faces of the peripheral groove."
  ],
  "cpc": [
    "F01D 5/32",
    "F01D 5/3038",
    "Y02T 50/60"
  ],
  "assignees": [
    "GEN ELECTRIC"
  ],
  "filing_date": "1971-05-25",
  "publication_date": "1973-03-20",
  "grant_date": "1973-03-20",
  "priority_date": "1971-05-25",
  "application_number": "US-3721506D-A",
  "family_id": "22518755"
}