Drive axle sleeve and seal assembly

A vehicle drive axle assembly adapted for use with a vehicle on board system for controlling tire pressure, the axle assembly comprising:

• a rigid tubular housing including a hollow nonrotatable spindle at opposite ends thereof and a rotatable drive shaft assembly having opposite ends thereof extending through an outboard end of each spindle for driving a wheel hub rotatably supported on each spindle;
• each spindle including a radially outwardly facing surface having first, second and third surfaces concentric to an axis of the spindle and in order of lesser diameter, the first and second surfaces extending axially outboard from an outboard facing shoulder, the third surface extending axially inboard from fastener threads in the outwardly facing surface at the outboard end of the spindle and axially separated from the second surface by an intermediate surface;
• bearing means for rotatably supporting the wheel hub on the spindle, the bearing means including inboard and outboard axially spaced apart bearing assemblies radially interposed between the second surface and the outwardly facing surface at the outboard end of the spindle and radially inwardly facing surfaces of the hub, each bearing having an inner race and an outer race;
• a fastener threadably received by the spindle fastener threads and reacting against the outboard bearing inner race for securing the hub on the spindle;
• a sleeve defining passage means for directing fluid pressure from a position inboard the inboard bearing assembly to a hub passage having an opening radially aligned with a passage extending radially through a cylindrical wall of the sleeve at a position between the bearing assemblies;
• the sleeve including inboard and outboard ends having means in sealing relations with the first and third surfaces, respectively, a first radially inwardly facing surface seated on the second surface, a radially outwardly facing surface supporting the inboard bearing inner race a second radially inwardly facing surface between the second and third spindle surfaces defining an annular passage in cooperation with the spindle intermediate surface, a groove in the first sleeve inwardly facing surface, the groove having an outboard end communicating with the radially extending passage in the sleeve via the annular passage, the groove having an inboard end communicating with a passage in the sleeve inboard end, the passage opening into the groove inboard end at a position outboard the sleeve sealing relation with the first surface;
• and
• first and second annular seals disposed on axially opposite sides of radially extending passages in the hub and sleeve with both seals in sealing relation with radially inwardly and outwardly facing surfaces respectively of the hub and sleeve for providing a sealed annular passage between the radially extending passages of the sleeve and the hub.