US Patent 10254072 Differential compound bow

A bow system and an idler wheel for the bow system (1) is provided. The bow system comprises a first limb (3) and a second limb (4), a riser (2) interconnecting the first (3) and second (4) limbs, a first (5) and a second (6) idler wheel, and a bowstring (9) arranged between the first (5) and the second (6) idler wheel. The first idler wheel (5) is rotationally journalled in a first end portion of the riser (2) and the second idler wheel (6) is rotationally journalled in a second end portion of the riser (2) such that both idler wheels (5, 6) are stationary when the bow system (1) is tensioned.