This section is from the book "Scientific American Reference Book. A Manual for the Office, Household and Shop", by Albert A. Hopkins, A. Russell Bond. Also available from Amazon: Scientific American Reference Book.
The chain is made up of square links which are engaged by ratchet-shaped teeth on the chain wheel.
The wheel is formed with pockets into which the links of the chain are adapted to fit.
The wheel is formed with two sets of teeth between which the chain travels. The teeth bear against the ends of the outer links of the chain.
This wheel is similar to that shown in Fig. 44, but has in addition a row of teeth along the center which bear against the center link of the chain.
The links are formed with projecting teeth which fit into notches on the rim of the chain wheel.
47. "Silent" Chain and Wheel. - This is a special type of chain in which each link is formed with a tooth at each end. The teeth of adjacent links coact to completely fill the spaces between the teeth of the chain wheel. The construction is such as to produce a noiseless operation of the chain gear even at high speeds.
Each link is formed with a tooth, which meshes with the teeth of the chain wheel. The construction of each link is such that it may be readily slipped into or out of engagement with the next link of the chain.