Anti-sabotage screw has threaded shaft and screw head with drive recess with helical guide grooves for engagement by screwdriver tool having helical coil shaft compatible with drive recess

摘要

The screw (100) has a shaft (120) with threaded section (122) and screw head (130) with drive recess designed as a helical screw coil through which torque can only be transferred in one direction. The helical coil has guide grooves (111) arranged circumferentially round the outer edge of the recess with the pitch of all the grooves being the same and larger than or equal to 45 degrees. The alignment of the screw coil corresponds to the alignment of the thread on the threaded section. - Independent claim describes screwdriver tool for fitting screw and having a shaft (210) with helical coil compatible with drive recess of screw and with star-shaped guide faces .