To make a rope engage with a sheave on counter-weight side easily.

This counter-weight is provided with a pair of up-light channels 3, 4 disposed in perpendicular direction, a side panel 6 mounted with bolts 7, 8 between a pair of up-light channels 3, 4, and a sheave which is supported at the side panel 6 so as to rotate freely and with which a rope 15 is engaged. By loosening the bolts 7, 8, the side panel 6 can be removed from the up-light channels 3, 4, and the rope 15 can be engaged with the sheave. By loosening the bolts 7, 8, the side panel 6 can be attached onto the up-light channels 3, 4 again.