This system features a conical drum that allows the balancing force to be adjusted depending on the rope extension length. When the rope is pulled out from this drum, an almost constant operating force is created that is independent of the rope extension length.

Difference to a spring balancer:

In contrast, a spring balancer uses a cylindrical drum whose diameter remains constant, regardless of the rope’s extension length. When the cable is pulled out, the spring force increases evenly and slightly in proportion to the pull-out length.