US 4,776,234 A · Modulating bias control for limited slip differential axle

Abstract

A limited slip differential axle assembly includes a plurality of pressure plate segments which are electromagnetically biased against friction discs of clutch packs secured to side gears of the differential. In a preferred form, the assembly is formed of a two-piece of "split" differential case and includes an armature ring rigidly coupled to a pressure plate loading ring. Electromagnetic coupling forces are adjustably controlled by a vehicular operator to permit modulation of bias for given road conditions, wherein a limited slip differential control may be effective to bias a clutch pack to provide a variable friction drag between at least one of the side gears and the differential case. For this purpose, an energizing coil is secured rigidly to the differential carrier, while a magnet shell member is rigidly affixed to one part of the split differential case. The armature ring cooperates with the magnet shell to form an air gap, the armature ring being threadably and hence adjustably secured to the loading ring disposed between the two relatively moveable parts of the split differential case.

Claims13

Dependent claims

In a limited slip differential axle assembly for use in a vehicle, said assembly including a carrier, a differential case rotatably mounted in said carrier, a pair of pinions mounted for rotation within said case, first and second side gears engaged with each of said pinions, a first plurality of friction discs fixed to said first side gear and interleaved with and disposed for engaging a second plurality of mating discs fixed to said case;

an improvement comprising means for modulating a preload force between said first plurality of friction discs and said second plurality of said discs, said means located between said first side gear and said pluralities of interleaved discs, said means including a plurality of pressure plate segments annularly disposed against at least one of said friction discs, said segments comprising cam surfaces disposed to urge said segments both radially and axially with respect to said friction discs and said first side gear as said preload force is changed.

In a limited slip differential axle assembly for use in a vehicle, said assembly including a carrier, a differential case rotatably mounted in said carrier, a pair of pinions mounted for rotation within said case, and a pair of side gears containing a first plurality of friction discs fixed to one of said side gears and disposed for engaging a second plurality of mating discs fixed to said case;

an improvement comprising means for electromagnetically biasing said first plurality of friction discs against said second plurality of mating discs, said means comprising a variably adjustable control apparatus, whereby an operator may selectively modulate bias for given road conditions, said adjustable control apparatus including a plurality of pressure plate segments located between said first side gear and said pluralities of discs and disposed for biasing together said first and second pluralities of friction discs, said apparatus further comprising a pressure plate loading ring, said ring and said segments containing mating cam surfaces, said ring being axially modulated by said electromagnetic means, whereby as said ring moves axially said pressure plate segments are disposed for movement both radially and axially with respect to said friction discs via the interaction of said mating cam surfaces.

Dependencies are inferred from the claim text.

Modulating bias control for limited slip differential axle

Life of this patent

Modulating bias control for limited slip differential axle

Life of this patent

Abstract

Claims13