Patent ID: 7207760

Claim:
A washer to be located between a nut and an object, comprising a body having an axis and provided with a first axial outer face surface located at one axial side and adapted to cooperate with the nut, a second axial outer face surface located at an opposite axial side and adapted to cooperate with the object to be assembled or disassembled, and at least one radially inner surface adapted to cooperate with a bolt; first means provided on said radially inner surface for providing a friction between said body and the bolt to frictionally impede the bolt from turning and at the same to allow the bolt to be displaced in an axial direction when the nut is turned; second means provided on said second axially outer face surface of said body for increasing friction of said second axially outer face surface of said body to increase a friction between said body and the object so as to impede said body from turning; and third means provided on said first axially outer face surface of said body for reducing a friction of said first axially outer face surface of said body to reduce a friction between said body and the nut so as to at least reduce dragging of said body into turning by the turning nut, so that when the nut is turned the body substantially is not dragged into turning because of said third means and said body is impeded additionally from turning by said second means so that said body of the washer does not turn and impedes the bolt from turning by said first means and thereby the body of the washer does not turn but is only displaced in an axial direction, said body including a radially inner portion provided with said radially inner surface having said first means for providing a friction between said body and the bolt, and a radially outer portion which does not have first means for providing a friction between said body and said bolt, so that said radially inner portion engages the bolt while said radially outer portion does not, and said radially inner portion displaces, in said axial direction relative to said radially outer portion, inside said radially outer portion.