| US 7,578,762 B2 | ||
| Four-wheel drive vehicle transmission | ||
| Franco Cimatti, Pavullo (Italy); and Carlo Neri, Modena (Italy) | ||
| Assigned to Ferrari S.p.A., (Italy) | ||
| Appl. No. 10/492,873 PCT Filed Oct. 15, 2002, PCT No. PCT/IT02/00658 § 371(c)(1), (2), (4) Date Jan. 14, 2005, PCT Pub. No. WO03/033939, PCT Pub. Date Apr. 24, 2003. |
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| Claims priority of application No. TO2001A0978 (IT), filed on Oct. 16, 2001. | ||
| Prior Publication US 2005/0119088 A1, Jun. 02, 2005 | ||
| Int. Cl. F16H 37/08 (2006.01) | ||
| U.S. Cl. 475—206 [475/207; 180/248] | 15 Claims |
| 1. A four-wheel-drive vehicle transmission (1) comprising:
an input shaft (8) rotated by a vehicle engine (2) about a first axis of rotation (A);
a front output shaft (10) connected to a front axle (3);
a rear output shaft (12) connected to a rear axle (4);
said input shaft (8) and said rear output shaft (12) being coaxial;
an auxiliary tubular shaft (14) mounted alongside said input shaft (8) to rotate about a second axis of rotation (D) parallel to said first axis of rotation (A);
at least one first group of gears (15, 16) for selectively connecting said auxiliary tubular shaft (14) mechanically to said input shaft (8);
a first countershaft (17) mounted for rotation about said second axis of rotation (D) inside said auxiliary tubular shaft (14);
a second countershaft (18) mounted for rotation about said second axis of rotation (D) opposite said first countershaft (17);
a planetary gear train (19) for mechanically connecting said auxiliary tubular shaft (14) to said first countershaft (17) and said second countershaft (18); and
a first (25) and a second (26) cascade gear set for mechanically connecting said second countershaft (18) to said rear output shaft (12), and mechanically connecting said first countershaft (17) to said front output shaft respectively (10);
said front output shaft (10) and said rear output shaft (12) are mounted for rotation respectively about a third axis of rotation (B) and a fourth axis of rotation (C), said third axis
of rotation (B) and said fourth axis of rotation (C) parallel to said first axis of rotation (A): and said planetary gear
train (19) positioned between said first countershaft (17) and said second countershaft (18), said planetary gear train (19) comprising:
a pinion (20) fitted to the end of said first countershaft (17);
a ring gear (21) carried by said auxiliary tubular shaft (14) so as to be coaxial with said pinion (10); and
a plurality of planet gears (23) mounted for rotation on a planet carrier flange (22) fitted to said second countershaft (18), said plurality of planet gears (23) meshing with said pinion (20).
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