Method and a device for the manufacturing of washers for locking and washer for locking
A method for the manufacturing of circular washers for locking from blanks, a washer having a central hole, a first side comprising a pattern of radially extending teeth and a second side comprising a pattern of radially extending cams. The method is especially comprised in the steps of producing a washer blank having an annular shape; introducing the washer blank into a die assembly for forming a closed shaping space by a lower die portion, an opposing upper die portion, a central die portion and a support piece, the central die portion extending through a washer blank central hole; forming the blank to a washer by mutual movement of said lower and upper die portions; and opening the closed shaping space to extract the formed washer. The invention also relates to a device and a washer.
1. A method for the manufacturing of circular washers for locking from blanks, a washer having a central hole, a first side comprising a pattern of radially extending teeth and a second side comprising a pattern of radially extending cams, comprising the steps of
producing a washer blank having an annular shape;
introducing the washer blank into a die assembly for forming a closed shaping space by a lower die portion, an opposing upper die portion, a central die portion and a support piece providing a circumferential outer wall of said closed shaping space, the central die portion extending through a washer blank central hole;
forming the blank to a washer, in said closed shaping space, by mutual movement of said lower and upper die portions;
opening the closed shaping space to extract the formed washer.
2. A method according to claim 1 , comprising the step of
cutting the blank from a thin strip.
3. A method according to claim 1 , comprising the step of
forming the blank from a wire having a circular cross-section.
4. A method according to claim 1 , comprising the step of
forming the blank from a wire having a square cross-section.
5. A method according to claim 2 , comprising the step of
cutting the blank in the die assembly prior to forming the blank.
6. A method according to claim 1 , comprising the steps of
introducing the washer blank material between the lower die portion and the upper die portion;
forcing the lower die portion against the upper die portion for forming the closed shaping space by the three die portions and the support piece by forcing the upper die portion, against an end stop with the blank material applied in said space; and
forming the blank to a washer by further forcing the lower die portion towards the upper die portion.
7. A method according to claim 6 , comprising the steps of
forcing the upper die portion towards the end stop against a spring force; and
pushing out the formed washer by the upper die portion by said spring force when unloading the force exerted by the lower die portion by retracting the lower die portion.
8. A method according to claim 1 , comprising the steps of
forming the washer with the tooth pattern and the cam pattern extending from the inner periphery of the washer to the outer periphery of the washer.
9. A method according to claim 1 , comprising the step of
forming the washer with a bevelled configuration at the inner periphery to adapt to a radius under the head of a bolt intended to be locked by a washer configuration, the bevelled configuration preferably being formed on the tooth pattern side of the washer.
10. A method according to claim 1 , comprising the step of forming washers with a thickness of down to less than 1 mm, the washers preferably having a standardized outer diameter.