Hydraulically operated disc clutch

{
  "publication_number": "US3805933A",
  "country": "US",
  "kind": "A",
  "title": "Hydraulically operated disc clutch",
  "abstract": "A fixed annular hydraulic cylinder gives radial support for an internal driving sleeve of the clutch, an annular piston internal of the cylinder acting axially through a large diameter needle bearing against a pressure platesplined to the sleeve and a stack of Belleville spring-separated discs sustained by a backing plate splined on the sleeve. Alternating discs of the stack are splined to the sleeve and an output cup or driven member. The circular median line or zone of the needle bearing is in axial alignment with that of the piston, disc stack and pressure and backup plates.",
  "claims": [
    "1. A hydraulically operated clutch comprising power input and output members drivingly connected releasably to one another by coaxial annular friction means having parts in rotatively fixed relation to said respective members to transmit rotative force between the latter when compressed axially, and means for the transmission of axial operating force through said compressed friction means, comprising an annular operating member subject to hydraulic pressure in a cylinder space of the clutch, an annular needle bearing interposed between said operating member and said friction means to apply axial clutch-engaging thrust from said operating member to the friction means, and means to prevent substantial rotation of said operating member in relation to said cylinder space under the frictional drag of the needle bearing, comprising an annular, wave-type spring interposed axially between said operating member and a wall part of said cylinder space, said spring having integral portions keyed respectively to the operating member and to a fixed part of the clutch to prevent said rotation of the operating member.",
    "2. The clutch of claim 1, in which said annular needle bearing is of a radius to encircle said input member in substantially outwardly spaced radial relation thereto, a medial annular zone of the needle bearing between inner and outer peripheries of the latter coinciding substantially with a corresponding annular median zone substantially common to said annular friction means and said annular operating member."
  ],
  "cpc": [
    "F16D 25/082"
  ],
  "assignees": [
    "FORMSPRAG CO"
  ],
  "filing_date": "1970-10-19",
  "publication_date": "1974-04-23",
  "grant_date": "1974-04-23",
  "priority_date": "1969-05-19",
  "application_number": "US-8211570-A",
  "family_id": "26767064",
  "citations": [
    "US3148144A",
    "US3429410A",
    "US3444971A"
  ]
}