The lengths of the links comply with the conditions: A͞B=D͞C, A͞D=B͞C and A͞E=E͞D. Hook 1 is connected by turning pair F to link BC of parallel-crank linkage ABCD. Point F of the hook suspension is displaced by the distance a from point E. Weight Q of the load being weighed equals Q=G(l/a), where G is the sliding weight and l is the arm of the sliding weight with respect to point E. Arm a can be very small so that the length of the beam need be relatively short. Weight P counterbalances the dead weight of the beam.
$787$LW,B$