Driving shaft 1 rotates about fixed axis A and is rigidly attached to (or integral with) gear 2. Gear 4 is freely mounted on driven shaft 5. Toothed clutch 3 is mounted on the splines at the left end of shaft 5 which rotates about fixed axis C. Clutch 3 consists of halves a and b, having internally toothed members e and f which engage the externally toothed clutch members c and d, integral with gears 2 and 4. Gears 2 and 4 mesh with gears 7 and 8 which are keyed to intermediate shaft 6, rotating about fixed axis B-B. When clutch 3 is shifted to the left so that the teeth of member e engage those of member c, rotation of driving shaft 1 is transmitted directly to driven shaft 5, i.e. shaft 5 rotates at the same speed as shaft 1. When clutch 3 is shifted to the right so that the teeth of member f engage those of member d, the clutch engages gear 4 and motion is transmitted from driving shaft 1 to driven shaft 5 through gears 2, 7, 8 and 4. The transmission ratio, in this case, is i₁₅=(z₇/z₂)(z₄/z₈) where z₂, z₄, z₇ and z₈ are the numbers of teeth of gears 2, 4, 7 and 8.
$2843$CxG,SR$