| 摘要 |
A split lock washer for locking a screw connection, including a pin bolt projecting non-rotatably from a substructure with a nut screwed onto the pin bolt or a bolt gripping through the substructure, has an inner lock washer (1) with friction teeth (2) engaging against the substructure and an outer lock washer (10) with friction teeth (11) engaging against the nut or the bolt head. The lock washers (10.1) mesh with each other along sloping surfaces (4). The sloping surfaces have an angle to a plane at right angles to the axis of the screw connection such that the lock washers (10,1) are separated from each other when the outer washer (10) together with the nut or bolt head are rotated relative the inner washer (1) in a direction for loosening the connection. For complete loosening of the screw connection the screw is elongated only about 10% in excess of the elongation it is subjected to for a normally tightened connection. The friction teeth (2.11) on the inner and the outer washers have a configuration such that they achieve a relatively small frictional torque against the respective substructure nut or bolt head, about the axis of the screw connection when tightening, but a relatively larger frictional torque against these parts when loosening the connection. The arrangement of substantially single action friction teeth (2.11) on the washers (1,10) enables an exactly controloable low tightening torque for the screw connection, whereby elongation of the bolt can be reliably kept within given limits. The corresponding slight slope of the sloping surfaces (4) facilitates loosening the connection and reduces the over-elongation of the bolt occurring during this operation. |
