초록 ▼

A differential gear mechanism of the limited slip type including a clutch pack (35) operable to retard rotation between the side gears (21,23) and the gear case (11). The clutch pack may be loaded, to retard differentiating action by means of a retarding mechanism (33) including a first ball ramp ac

A differential gear mechanism of the limited slip type including a clutch pack (35) operable to retard rotation between the side gears (21,23) and the gear case (11). The clutch pack may be loaded, to retard differentiating action by means of a retarding mechanism (33) including a first ball ramp actuator (43) operable to cause axial movement of a plurality of elongated engagement members (61). When the members (61) move axially, a cone clutch assembly (79) is engaged, which retards rotation of a ramp plate (73) of a second ball ramp actuator (71). It is the ramping action of the second ball ramp actuator (71) which applies a load to the clutch pack (35) to limit, or prevent, differentiation within the differential gearing.

대표청구항 ▼

1. A differential gear mechanism of the type including a gear case, and defining an axis of rotation and a gear chamber; a differential gear set disposed in said gear chamber and including at least one input gear and first and second output gears; a retarding mechanism for retarding differentiating

1. A differential gear mechanism of the type including a gear case, and defining an axis of rotation and a gear chamber; a differential gear set disposed in said gear chamber and including at least one input gear and first and second output gears; a retarding mechanism for retarding differentiating action of said differential gear set, including a clutch pack disposed adjacent said second output gear, and operable between an engaged condition, effective to retard relative rotation between said output gears and said gear case, and a disengaged condition; said retarding mechanism including a first ball ramp actuator disposed adjacent said first output gear and further including an electromagnetic actuator disposed adjacent said first ball ramp actuator and operable, in response to an electrical input signal, to cause ramping action of said first ball ramp actuator; a plurality of elongated engagement members having upstream end portions generally associated with said first ball ramp actuator and operable to move axially toward said second output gear in response to said ramping action of said first ball ramp actuator; said elongated engagement members having downstream end portions operably associated with a clutch pack loading mechanism and operable, in response to said axial movement of said engagement members to apply a load to said clutch pack tending to change said clutch pack from said disengaged condition to said engaged condition; characterized by: (a) said clutch pack loading mechanism comprising a second ball ramp actuator disposed axially between said second output gear and said clutch pack, said second ball ramp actuator including a rotatable ramp plate; and (b) said clutch pack loading mechanism further comprising a cone clutch assembly comprising an input member, operably associated with said downstream end portions of said engagement members, and defining a first cone clutch surface and said rotatable ramp plate defining a mating, second cone clutch surface, said first and second cone clutch surfaces being moved toward engagement in response to said axial movement of said engagement members, to initiate ramping action of said second ball ramp actuator. 2. A differential gear mechanism as claimed in claim 1, characterized by said first ball ramp actuator having a first, relatively steeper ramp angle and said second ball ramp actuator having a second, relatively shallower ramp angle. 3. A differential gear mechanism as claimed in claim 2, characterized by said first, relatively steeper ramp angle is in the range of about 4 degrees to about 20 degrees. 4. A differential gear mechanism as claimed in claim 2, characterized by said second, relatively shallower ramp angle is in the range of about 2 degrees to about 4 degrees. 5. A differential gear mechanism as claimed in claim 1, characterized by said first ball ramp actuator and said electromagnetic actuator being disposed external to said gear case and mounted to permit rotation of said gear case relative to said actuators. 6. A differential gear mechanism as claimed in claim 1, characterized by each of said plurality of elongated engagement members defining an axis oriented generally parallel to said axis of rotation, each of said engagement members moving along said axis during said axial movement. 7. A differential gear mechanism as claimed in claim 1, characterized by said second ball ramp actuator comprising said second output gear including a radially-extending flange-like portion, said rotatable ramp plate being disposed axially between said flange-like portion and said clutch pack, and a plurality of balls being disposed between said flange-like portion and said rotatable ramp plate.