×

Device for winding a seat belt in vehicles

  • US 3,970,266 A
  • Filed: 04/03/1975
  • Issued: 07/20/1976
  • Est. Priority Date: 04/25/1974
  • Status: Expired due to Term
First Claim
Patent Images

1. A device for winding up an elongate flexible element, such as a vehicle safety belt, comprising a casing, an axle mounted in said casing and rotationally fast therewith, a hollow winding-drum rotatably mounted in said casing coaxial with and surrounding said axle, an annular piston positioned between said drum and axle and axially movable relative thereto between initial and final positions, an annular pressure chamber defined within said drum by said piston in said initial position thereof, a pyrotechnic charge for pressurising said pressure chamber with combustion gases therefrom to propel said piston axially along said drum and axle from said initial position, to said final position, first cooperable guide means on said piston and said drum, and second cooperable guide means on said piston and said axle, said first and second guide means being so arranged that said piston is rotationally fast with said drum or said axle and is movable along a helicoidal path relative to said axle when the piston is rotationally fast with said drum and is movable along a helicoidal path relative to said drum when the piston is rotationally fast with said axle, whereby axial displacement of the piston by the combustion gases causes said drum to be rotated for winding said flexible element on to said drum.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×