Granted Patent B2

US 7,101,301 · App. 10/738,565 · Granted Sep 5, 2006

Abstract

Claims (31)

1. A planetary gear arrangement for a transfer case comprising:

first, second and third planetary gear members;

said first planetary gear member continuously connected with an input;

said second planetary gear member continuously connectable with a rear axle;

said third planetary gear member selectively connectable with a front axle through a clutching arrangement; and

said third planetary gear member being selectively connectable with ground through a friction clutch;

wherein said clutching arrangement comprises a one way clutch and dog clutch connected in parallel, said one way clutch and dog clutch being independently engageable;

whereby the planetary gear arrangement functions as a gear ratio producing device when said friction clutch is engaged, and as a center differential when said clutching arrangement is engaged.

2. The planetary gear arrangement of claim 1 , wherein said first planetary gear member comprises a carrier, said second planetary gear member comprises a ring gear, and said third planetary gear member comprises a sun gear.

3. The planetary gear arrangement of claim 1 , wherein the planetary gear arrangement is operative as a center differential when said dog clutch or one way clutch is engaged.

4. The planetary gear arrangement of claim 1 , wherein an overdrive ratio produced by engagement of the friction clutch is approximately 1.5:1.

5. A drive train for a vehicle comprising front and rear axles, and a transfer case having a simple planetary gear set including:

a carrier continuously connected with an input;

a ring gear continuously connected with the rear axle;

a sun gear selectively connectable with the front axle through a clutching arrangement, wherein said clutching arrangement comprises a one way clutch and dog clutch connected in parallel, said one way clutch and dog clutch being independently engageable; and

said sun gear being selectively connectable with ground through a friction clutch;

whereby the simple planetary gear set functions as a gear ratio producing device when said friction clutch is engaged, and as a center differential when said clutching arrangement is engaged as a result of the connection of the rear axle with the front axle through a road surface upon which wheels supported by the front and rear axles rest.

6. The drive train of claim 5 , wherein the planetary gear arrangement is operative as a center differential when said dog clutch or one way clutch is engaged.

7. The drive tram of claim 5 , wherein an overdrive ratio produced by engagement of the friction clutch is approximately 1.5:1.

8. The drive train of claim 5 , wherein the front and rear axles have different axle ratios.

9. A drive train for a vehicle comprising front and rear axles, and a transfer case with a simple planetary gear set including:

a carrier continuously connected with an input;

a ring gear continuously connected with the rear axle;

a sun gear selectively connectable with the front axle through a clutching arrangement, wherein said clutching arrangement comprises a one way clutch and dog clutch connected in parallel, said one way clutch and dog clutch being independently engageable;

said sun gear being selectively connectable with ground through a friction clutch;

whereby the simple planetary gear set functions as a gear ratio producing device when said friction clutch is engaged, and as a center differential when said dog clutch or one way clutch is engaged as a result of the connection of the rear axle with the front axle through a road surface upon which wheels supported by the front and rear axles rest; and

wherein an overdrive ratio produced by engagement of the friction clutch is approximately 1.5:1.

10. A two speed transfer ease connectable between a transmission and front and rear axles of a vehicle, the transfer case comprising:

a single planetary gear set having a sun gear, a carrier and a ring gear which are operatively engaged with at least two clutches to alternatively function as a center differential or a gear ratio producing device between the transmission and the front and rear axles and

wherein said at least two clutches include a one way clutch and dog clutch connected in parallel, said one way clutch and dog clutch being independently engageable.

11. The two speed transfer case of claim 10 , wherein said sun gear is engageable with the front axle through a clutching arrangement of said at least two clutches, and said sun gear is connectable with ground through a friction clutch of said at least two clutches; and wherein the planetary gear set functions as a gear ratio producing device when said friction clutch is engaged, and as a center differential when said clutching arrangement is engaged.

Assignments (13)