Patents Assigned to Cryotherm Limited
  • Screw unit to join semi-rigid mats together
    Patent number: 4917554
    Abstract: A screw unit with a shaft (1) and an enlargement at one end, to join together semi-rigid mats, consisting for example of mineral fibers or foam material, has the shaft (1) consisting of a wire helix (W) wound in corkscrew fashion and continuing at the one end as a spiral winding forming the headpiece (2), with the helical slope (.alpha.) of the wire helix (W) adjacent the headpiece (2) being smaller than the helical slope (.beta.) in the region of a point (5) at the other end of the shaft (1).
    Type: Grant
    Filed: March 29, 1989
    Date of Patent: April 17, 1990
    Assignee: Cryotherm Limited
    Inventor: Walter Bronn