Movement No. 141 demonstrates the endless band saw mechanism — a classic and highly efficient cutting system that converts continuous rotary motion of pulleys into continuous rectilinear motion of the saw blade. A continuous loop of toothed saw blade is stretched around two pulleys — one driven by the power source and one acting as an idler to maintain tension. As the drive pulley rotates, it carries the blade around in a continuous loop. The straight sections of the blade between the two pulleys move in a constant linear direction — one side moving downward (the cutting side) and the other side returning upward. Because the blade moves continuously in one direction without reversing, it cuts more smoothly and efficiently than a reciprocating saw. The band saw principle allows for long, continuous cuts through wood, metal, and other materials, and forms the basis of modern band saw machines used widely in woodworking, metalworking, and meat processing industries.
141. Endless-band saw. Continuous rotary motion of the pulleys is made to produce continuous rectilinear motion of the straight parts of the saw.