Spider washer head screw
Patent 4350465 Issued on September 21, 1982. Estimated Expiration Date: 
April 28, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
April 28, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 1938399 2226491 2266555 3343580 InventorAssigneeApplicationNo. 06/144702 filed on 04/28/1980US Classes:411/186, And includes resilient flange411/165Each twisted about its radial axisExaminersPrimary: Britts, Ramon S.Attorney, Agent or FirmInternational ClassesF16B 39/00 (20060101)F16B 39/26 (20060101) F16B 39/282 (20060101) AbstractA screw having a head and a body defining an axis of rotation extending downwardly from the head and formed integrally therewith is provided with a flange extending radially and downwardly from the head about the upper end of the body. The flange is slotted to define a plurality of deformable tabs joined at their respective bases to the head. At least a portion of each tab is twisted relative to its base about an axis extending along the flange radially from the axis of rotation in a direction so that an edge of each tab defined by the slots, the edge being on the side of the tab facing in the direction of rotation of the screw for removal, projects downwardly. The respective ends of the edge lie in essentially a single plane extending normally to the axis or rotation, the bottom surface of the tabs defining an essentially straight line in radial cross-section except in the region of twist. | |
