FOUR-SPEED REVERSIBLE GEARBOX MECHANISM WITH A CLUTCH ON THE INPUT SHAFT

Gear 8 is keyed to input shaft 1 and is in constant engagement with gear 11. Clutch 3 slides along square guide a of output shaft 2. Gear 9 rotates freely on shaft 2 and is in constant engagement with gear 12. Gear 4 slides along square guide b of shaft 2 and can be shifted into engagement with either gear 5 or 6. Gear 6 rotates freely about intermediate shaft 9 and is in constant engagement with gear 7. Gears 7, 5, 12 and 11 are keyed to shaft 10. When driving shaft 1 rotates, driven shaft 2 can have any one of three speeds for which clutch 3 is engaged either to gear 8 or 9 with gear 4 disengaged, or gear 4 is shifted into engagement with gear 5 with clutch 3 in the neutral position. The corresponding transmission ratios are i₁₂=1, i₁₂=(z₁₁/z₈)(z₉/z₁₂) and i₁₂=(z₁₁/z₈)(z₄/z₅). If gear 4 is shifted into engagement with gear 6, then the fourth transmission ratio is i₁₂=-(z₁₁/z₈)(z₄/z₇) where z₄, z₅, z₇, z₈, z₉, z₁₁ and z₁₂ are the numbers of teeth of gears 4, 5, 7, 8, 9, 11 and 12. Shaft 2 is reversed by the engagement for the fourth speed. Thus shaft 2 has three forward speeds and one reverse speed.
$2853$CxG,SR$