Drumless Hoist : Design and Manufacture as Manual Operation

Abstract

The chain block is the most compact hoist. However, it has the disadvantage of the use of a heavy chain, non uniform velocity, and difficult prediction of breakage compared to the wire hoist. On the other hand, the typical wire hoist with a drum uses needless long space, moreover, some one produces the movement of the load along the direction of the drum axis through the length of the drum by asymmetrical reeving. The apparatus shown here can decrease the tension of the wire caused by the load to zero by means of several springs and links set in the inside of a sheave during one rotation. This idea is referred to in the german literature. The literature doesn't include, however, the deliberate design and an actual product. Furthermore, this hoist is not of a small size upon construction. The drumless hoist shown here is designed and manufactured for a 100 kg load and results prove is to be successful.