Fig. 106
[Fig. 107] is the section of a groove suitable for fibre rope driving. The rope is gripped at its sides, thus increasing its driving power.
[Fig. 108] is the section of a groove where the pulley is used as a guide only, the rope being allowed to rest on the bottom.
[Fig. 109] is the section of a groove used for wire rope. The groove is lined on the bottom with pieces of wood or leather to give greater friction, as the rope would be injured if it were gripped in a groove as [fig. 107].
[Figs. 110] and [111] are the sections of grooves suitable for chains, the groove receiving every other link, the alternate links lying flat.
[Fig. 110] is suitable where the pulley is used as a guide only, and fig. 111 is used for driving pulleys as in Weston’s blocks.
The part elevation shown in [fig. 112] is known as a sprocket wheel, and shows the sprockets cast in the groove upon which the links catch. It is used for driving purposes.
Fig. 107