Abstract:
A hydraulic actuation system (10) and method of assembly for disconnecting a secondary driveline (27) can be used in an all-wheel drive (AWD) vehicle (14) having a power take-off unit (PTU) (42) for transferring rotary power to the secondary driveline (27). The hydraulic actuation system (10) can include a source of pressurized fluid (50), a hydraulically actuated synchronizer (44) for synchronizing rotary motion between the PTU (42) and the secondary driveline (27), at least one hydraulically actuated clutch assembly (11a, 11b) for connecting and disconnecting secondary vehicle wheels (29a, 29b) with respect to the secondary driveline (27), an area control solenoid (ACS) valve (54) in fluid communication with the source of pressurized fluid (50) to modulate pressure to engage and disengage the synchronizer (44), and at least one variable force solenoid (VFS) valve (56a, 56b) in fluid communication with the source of pressurized fluid (50) to modulate pressure to the at least one hydraulically actuated clutch assembly (11a, 11b).
Abstract:
A disconnect mechanism (10) for a secondary driveline (12) and method of assembly can be used in an all-wheel drive (AWD) vehicle having a rear driveline module (RDM) (20) for changing drive modes between a two-wheel drive mode and an AWD mode. The disconnect mechanism (10) can include a hydraulically actuated coupling clutch (34) connected to a power take-off unit (PTU) for transferring rotary power from the PTU (36) to the RDM (20) during the AWD mode, a hydraulically actuated first and second rear clutch (30, 32) for rotationally connecting and disconnecting corresponding first and second rear axles (14a, 14b) drivingly coupled to rear wheels (16a, 16b) during the AWD mode and two-wheel drive mode, respectively, and a hydraulic actuating assembly (40) including a source of pressurized fluid (44) for actuating the coupling clutch (34), the first rear clutch (30), and the second rear clutch (32), and for synchronizing any speed differential therebetween.