WRENCH-MULTIPLIER Russian patent published in 2003 - IPC

FIELD: tools for screwing and unscrewing stud (bolt) joints, practically in all branches of building industry and machine engineering. SUBSTANCE: wrench-multiplier for screwing and unscrewing nuts on (off) studs (bolts) with slit on their ends includes mechanism for increasing torque having combined by means of core pinion-shaft and driven gear wheel with head fit onto nut screwed on end of stud (bolt); member for fixing position of stud (bolt) in the form of polyhedron with pointed flat head inserted in slit of stud (bolt) and arranged along axis of core in through polyhedral opening. Such operation may be realized by one operator without holding stud (bolt) against cranking. EFFECT: enhanced technological effectiveness of screwing and unscrewing stud (bolt) joints in hard-to-reach places. 2 dwg