Baffle for lubrication management in an axle assembly

#The present disclosure relates to lubrication management devices for front and rear axles for a vehicle.

#Vehicle driveline components such as gears, bearings, and other elements require lubrication. Various characteristics of the lubricating fluid, such as viscosity, temperature, and fluid levels may affect durability, drivability, and fuel economy.

#A vehicle axle includes a housing defining a sump, a gear assembly and a baffle. The gear assembly includes a ring gear disposed within the housing. The ring gear is configured to pump fluid throughout the housing. A pinion gear is meshed with the ring gear. The baffle is disposed within the sump and connected to the housing. The baffle has a first part being configured to control fluid flow across the ring gear and a second part attached to the first part. The second part is configured to control fluid flow across the pinion gear.

#FIG. 1 is a top schematic view of a vehicle having a rear axle assembly;

#FIG. 2 is a perspective view of the axle assembly showing a baffle within the housing of the axle assembly;

#FIG. 3 is a perspective view of the baffle structure around a ring and pinion gear set of the axle assembly; and

#Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.

#Referring to FIG. 1, a schematic of a vehicle 10 is shown. The vehicle 10 includes an engine/transmission 12, a differential 14 which includes a ring gear 16 and a housing 18, and a sump 20. The engine/transmission 12 provides torque. The differential 14 transfers torque from the engine/transmission 12 to the vehicle wheels 13. The ring gear 16 of the differential 14 spins allowing torque from the engine/transmission 12 to be transferred to the wheels 13. The ring gear 16, as it spins, pumps lubricating fluid within the differential 14. Pumping the lubricating fluid exerts some torque on ring gear 16 which decreases the torque transmitted to the wheels 13. This is known as a speed related spin loss. Spin loss occurs when vehicle speed is lost due to increased fluid levels within the sump 20.

#Management of the fluid levels within the sump 20 may further aid to reduce spin loss of the vehicle 10 as well as significant churn drag loss generated from the strong pumping flow by the ring gear 16. The differential 14 may further include a gear assembly 22, which includes the ring gear 16 as well as a pinion gear 24 coupled to the ring gear 16 to transfer torque from the engine/transmission 12 to the vehicle wheels 13. Reducing the speed related spin loss as well as the churn drag loss further requires management of the fluid levels within the sump 20 such that the ring gear 16 pumps less fluid across the gear assembly 22 including the pinion gear 24 to avoid over flooding at a tail bearing (not shown). Further, optimization of fluid management within the differential 14 provides greater overall efficiency of the vehicle 10 and therefore improves fuel economy of the vehicle 10.