Limited slip differential with negligible bias under light load conditions

Abstract

A geared differential of the limited slip type wherein spring or bias means, exerting a predetermined force, are interposed between the outer ends of the side gears and adjacent portion of the differential carrier housing for urging each side gear in a direction opposite to the direction of the axial force applied to the side gear, via the planetary gear, thereby normally tending to urge the clutch friction discs into disengagement as long as the predetermined force is greater than the axial force, thereby permitting a high differential bias under heavy drawbar conditions and a relatively low bias under light drawbar conditions.

What is claimed is:  .[.1. A limited slip differential mechanism comprising: 
     
        under heavy load conditions..]. .[.4.  The limited slip differential mechanism of claim 3 further including second spring means, exerting a second predetermined force, situated between said carrier housing and an adjacent thrust side surface of said second side gear axially spaced from said second side gear inner annular end surface, whereby said second side gear is urged in a direction opposite to the direction of said axial force applied to said second side gear, thereby urging said second clutch friction discs into disengagement when said predetermined force is greater than said axial force..]. .[.5. The limited slip differential mechanism of claim 4 wherein said first and second spring means each comprise a Belleville spring, with one margin thereof being in contact with said carrier housing and the other margin thereof being in contact with said adjacent thrust side surface of said respective side gear..]. .[.6. In a limited slip differential mechanism of the type having a cross disposed within a differential carrier housing and connected for rotation therewith about an axis of rotation, a planetary gear carried by the cross, an axle shaft rotatably carried by said carrier housing, a side gear disposed within the carrier housing and having its teeth engaged with the teeth of the planetary gear, with the inner end of said axle shaft being drivingly connected with said side gear, and friction clutch means for transmitting torque between the carrier housing and the side gear wherein the clutch means is disposed between an adjacent part of the carrier housing and an inner annular end surface of the side gear and includes a first friction means connected to the carrier housing and a second friction means connected to the side gear whereby an axial force applied to the side gear, via the planetary gear, urges the clutch means first and second friction means into engagement and thus restricts the differential action of the mechanism, wherein the improvement comprises biasing means, exerting a predetermined force, located between said carrier housing and an adjacent thrust side surface of said side gear axially spaced from said side gear inner annular side surface, whereby said side gear is urged in a direction opposite to the direction of said axial force applied to the side gear, via said planetary gear, thereby urging said clutch means first and second friction means into disengagement when said predetermined force is greater than said axial force, thereby providing a negligible differential bias under light load conditions..]. .[.7. The improved differential mechanism of claim 6 wherein said biasing means comprises a Belleville spring, with one radial surface thereof engaging said carrier housing, and the other radial surface thereof engaging said side gear thrust side surface..]. .Iadd. 8. A limited slip differential mechanism comprising: a. a differential carrier housing;   b. a cross disposed within said carrier housing and connected for rotation with the carrier housing;   c. an axle shaft rotatably carried by said carrier housing;   d. a planetary gear carried by said cross;   e. a side gear disposed within said carrier housing, and rotatable about the carrier housing axis of rotation, said side gear being disposed adjacent to said cross, with the teeth of said side gear engaging with the teeth of said planetary gear, with the inner end of said axle shaft being drivingly connected with said side gear;   f. friction clutch means for transmitting torque between the carrier housing and said side gear, said clutch means being disposed between an adjacent part of said carrier housing and an inner annular side surface of said side gear and including first friction means connected to the carrier housing and second friction means connected to said side gear whereby an axial force applied to said side gear, via said planetary gear, urges said clutch means first and second friction means into engagement and thus restrict the differential action of said mechanism; and   g. spring means capable of exerting a predetermined force, situated between a further adjacent part of said carrier housing and a first annular thrust side surface of said side gear adjacent to said spring means and axially spaced from said side gear inner annular end surface whereby said side gear is urged in a direction opposite to the direction of said axial force applied to said side gear via said planetary gear, thereby normally tending to urge said clutch means first and second friction means into disengagement as long as said predetermined force is greater than said axial force, thereby providing negligible bias to said axle shaft under light load conditions, wherein said spring means comprises a Belleville spring, with one radial surface thereof engaging said further adjacent part of said carrier housing and the other radial surface thereof engaging said side gear first annular thrust side surface, thereby normally tending to urge said clutch means first and second friction means into disengagement as long as said axial force is less than said predetermined force. .Iaddend..Iadd. 9. A limited slip differential mechanism comprising:   a. a differential carrier housing rotatable about an axis of rotation;   b. a cross disposed within the carrier housing and connected for rotation with the carrier housing, said cross having first and second opposite sides facing along the carrier housing axis;   c. first and second aligned axle shafts rotatably carried by said carrier housing;   d. a planetary gear carried by said cross;   e. a first side gear disposed within the carrier housing on said first side of said cross and rotatable about the carrier housing axis of rotation, the gear teeth of said first side gear engaging in the teeth of said planetary gear, with the inner end of said first axle shaft being drivingly connected with said first side gear;   f. a second side gear disposed within the carrier housing on said second side of said cross and rotatable about the carrier housing axis of rotation, the gear teeth of said second gear engaging in the teeth of said planetary gear, with the inner end of said second axle shaft being drivingly connected with said second side gear;   g. a first clutch for transmitting torque between the carrier housing and said first side gear, said first clutch being disposed between said carrier housing and an inner annular end surface of said first side gear and including a driving friction disc connected to the carrier housing and a driven friction disc connected to said first side gear;   h. a second clutch for transmitting torque between the carrier housing and said second side gear, said second clutch being disposed between said carrier housing and an inner annular end surface of said second side gear and including a driving friction disc connected to the carrier housing and a driven friction disc connected to said second side gear, whereby an axial force applied to one of said side gears urges its respective clutch friction discs into engagement to restrict the differential action of said mechanism;   i. first spring means, exerting a first predetermined force, situated between said carrier housing and an adjacent thrust side surface of said first side gear axially spaced from said first side gear inner annular end surface, whereby said first side gear is urged in a direction opposite to the direction of said axial force applied to said first side gear, thereby urging said first clutch friction discs into disengagement when said predetermined force is greater than said axial force, thereby providing a negligible differential bias under light load conditions, said first clutch discs being urged into engagement when said axial force is greater than said predetermined force, thereby providing a high differential bias under heavy load conditions; and   j. second spring means, exerting a second predetermined force, situated between said carrier housing and an adjacent thrust side surface of said second side gear axially spaced from said second side gear inner annular end surface, whereby said second side gear is urged in a direction opposite to the direction of said axial force applied to said second side gear, thereby urging said second clutch friction discs into disengagement when said predetermined force is greater than said axial force, wherein said first and second spring means each comprise a Belleville spring, with one margin thereof being in contact with said carrier housing and the other margin thereof being in contact with said adjacent thrust side surface of said respective side gear. .Iaddend..Iadd. 10. In a limited slip differential mechanism of the type having a cross disposed within a differential carrier housing and connected for rotation therewith about an axis of rotation, a planetary gear carried by the cross, an axle shaft rotatably carried by said carrier housing, a side gear disposed within the carrier housing and having its teeth engaged with the teeth of the planetary gear, with the inner end of said axle shaft being drivingly connected with said side gear, and friction clutch means for transmitting torque between the carrier housing and the side gear wherein the clutch means is disposed between an adjacent part of the carrier housing and an inner annular end surface of the side gear and includes a first friction means connected to the carrier housing and a second friction means connected to the side gear whereby an axial force applied to the side gear, via the planetary gear, urges the clutch means first and second friction means into engagement and thus restricts the differential action of the mechanism, wherein the improvement comprises biasing means, exerting a predetermined force, located between said carrier housing and an adjacent thrust side surface of said gear axially spaced from said side gear inner annular side surface, whereby said side gear is urged in a direction opposite to the direction of said axial force applied to the side gear, via said planetary gear, thereby urging said clutch means first and second friction means into disengagement when said predetermined force is greater than said axial force, thereby providing a negligible differential bias under light load conditions, wherein said biasing means comprises a Belleville spring, with one radial surface thereof engaging said carrier housing, and the other radial surface thereof engaging said side gear thrust side surface. .Iaddend.