{
  "$type": "site.standard.document",
  "description": "An oil ring 1 comprises an annular oil ring body 10 having a pair of rail portions 12 at its axially upper and lower portions and butt ends, and a coil expander 20 assembled in the inner periphery of the oil ring body 10. The cross-sectional profile taken in the radial direction of the outer…",
  "path": "/patents/1070796",
  "publishedAt": "2006-01-18T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F02F5/00",
    "RIKEN KK [JP]"
  ],
  "textContent": "An oil ring 1 comprises an annular oil ring body 10 having a pair of rail portions 12 at its axially upper and lower portions and butt ends, and a coil expander 20 assembled in the inner periphery of the oil ring body 10. The cross-sectional profile taken in the radial direction of the outer peripheral sliding surface (f) of the pair of rail portions 12 has a nearly straight region (f1) with a length of equal to or more than 0.05 mm in the center and curved regions (f2) formed on both sides of the straight region (f1).",
  "title": "OIL RING, METHOD OF PRODUCING THE SAME, AND PISTON STRUCTURE USING THE OIL RING"
}