Two identical pulleys 1 and 2 rotate about fixed axes A-A and B-B which intersect at point 0 at angle φ. Belt 5 runs over pulleys 1 and 2, and over guide pulleys 3 and 4 which rotate freely on fixed axle 6 about fixed axis C. The transmission ratio from pulley 1 to pulley 2 is i₁₂=1, i.e. the pulleys rotate at equal speeds and, looking along axes A-A and B-B in the directions of the arrows, they both rotate clockwise. Pulleys 3 and 4 rotate in opposite directions.
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