Getriebe, insbesondere fuer landwirtschaftlich genutzte Motorfahrzeuge

959,763. Variable speed epicyclic gear; friction clutches. DEERE & CO. May 8, 1963 [May 21, 1962], No. 18198/63. Headings F2C and F2D. A variable speed gear comprises a three element epicyclic train in which an output shaft is connected to the first element, a positive driving means is connected to the second element and a variable speed driving means is connected to the third element, two concentric friction clutches being engageable between the second element and the positive driving means and between the second element and one of the other elements. Torque from a main input 14 is divided by gears 97 to a constant speed input shaft 94 and an expanding pulley gear 70, the two inputs being applied to a planet carrier 42, through a gear 60 and clutch L, and to a sun gear 28 of a three element train having a ring gear 30 connected to the output shaft 34. The planet carrier 42 has an annular outer casing 46 containing multiplate friction clutch and brake H and R engaged by fluid pressure on a doubleacting piston assembly 106; the clutch and brake being between the planet carrier and the ring gear and a stationary member 22 respectively. The gearing provides three bands of variable ratios: reverse with brake R engaged to lock the planet carrier; low with clutch L engaged and input drive from shaft 94 to the planet carrier and from the variable gear 70 to the sun gear; high with clutch H engaged to lock the carrier and ring gear with input from the variable gear only. The ratio of the epicyclic train is such that change from low to high may be made at the same output shaft speed without change in the variable gear, and low has a negative output providing slow speed reverse.