Washer for fastener and for fastening of objects

A threaded fastener for connecting two parts which constitute an object, comprising a bolt having a thread and an axis and introducable into the parts forming an object;

• a nut screwable on said bolt;
• and a washer to be applied between said nut and said object, said washer having an axis and being provided with a first bearing face surface located at one axial side and adapted to cooperate with said nut, a second bearing face surface located at an opposite axial side and adapted to cooperate with said object, and at least one third turning resistant surface adapted to cooperate with a bolt with said thread of said bolt, so that when said nut is turned with said given force in one direction and said washer receives simultaneously said given force in an opposite direction, only said nut turns to tighten or loosen said bolt and said washer remains rotation stationary while said bolt elongates or relaxes in an axial direction.

A method of assembling at least two parts with one another, comprising the steps of introducing a bolt having a thread and an axis into the parts so that a free end portion of the bolt extends outwardly beyond at least one side of the two parts;

• placing a friction washer on said free end portion of said bolt so that said friction washer engages with said thread of said bolt to create a turning friction between said washer and said bolt and so as to abut against said at least one side of the parts;
• threadably connecting a nut to said free end portion of said bolt so as to abut against the friction washer and to form an assembly;
• placing a torque power tool on the assembly so as to tighten or loosen the nut with a turning portion of said torque power tool connected to the nut to overcome a threaded friction with the bolt and a facial friction with the friction washer to turn the nut, and with a reaction portion of the torque power tool connected to the washer to absorb a reaction force due to a facial friction of the friction washer with the nut, a facial friction of the washer with said at least one side of the two parts and a turning friction with the bolt selected so that the washer does not turn but absorbs the reaction force of the torque power tool and so that the bolt elongates or relaxes in an axial direction.

A washer to be applied between a nut threadingly connected with the bolt which has an axis and is introduced into an object including at least two parts to be assembled, the washer comprising a body having an axis and provided with a first friction area, a first bearing face surface located at one axial side and adapted to cooperate with a nut, a second friction area, a second bearing face surface located at an opposite axial side and adapted to cooperate with the object, and at least a third friction area, a surface adapted to cooperate with a thread of the bolt, so that when the nut is turned with a given torque in one direction the nut turns to tighten or loosen the bolt while said body of the washer remains rotation stationary as the bolt elongates and relaxes.