Robert H Bragg

US Patent:

42122244, Jul 15, 1980

Filed:

Sep 25, 1978

Appl. No.:

5/945169

Inventors:

Robert C. Bragg - Amesbury MA
John T. Hawley - North Chelmsford MA

Assignee:

American Optical Corporation - Southbridge MA

International Classification:

F16B 3500
F16B 3900

US Classification:

85 1K

Abstract:

A combined threaded fastener and a collar adapted to be secured to the fastener around the shank portion of the fastener adjacent the head thereof. The shank portion of the fastener is adapted with a shoulder portion disposed adjacent the head portion and extending lengthwise of the shank of the threaded fastener for a predetermined extent. Adjacent the shoulder is an annular groove which in the preferred embodiment is generally circular in cross-section. The collar has an annular flange which serves as the bearing portion and is adapted to cooperate with the head portion of the fastener and a sleeve portion attached or extending longitudinally of the flange or bearing portion. The sleeve portion has a diameter sufficient so as to receive the shank portion of the fastener therein. The sleeve portion of the collar is also adapted with an annular groove which again in the preferred embodiment is substantially of circular cross-section. The annular groove is selected so as to be less than the thickness of the mounting means into which the fastener and collar are installed and further is adapted to contain a volume of material in the remaining portion of the sleeve adjacent said groove so as to be compressible into the annular groove of the fastener shank.