Patent Application
20110017005
This disclosure relates to a ring and pinion gear set design, such as for a vehicle, and more particularly to a reduced friction ring and pinion gear design that utilizes rolling element bearings in the pinion gear.
Many vehicles utilize a ring and pinion gear set in order to transfer power from a transmission of a vehicle into axles of the vehicle in order to drive wheels of the vehicle. As shown in
Therefore, a need exists for a ring and pinion gear set that reduces friction at the interface between a pinion gear and a ring gear and easies the ability to obtain proper gear mesh between the pinion gear and the ring gear.
Discussed herein are a number of embodiments of a ring and pinion gear set. According to one embodiment, a ring and pinion gear set comprises a ring gear and a pinion gear. The pinion gear has a plurality of rolling elements. The plurality of rolling elements is disposed about at least a portion of a periphery of the pinion gear. The ring gear has a plurality of mating grooves. The plurality of rolling elements of the pinion gear is engageable with the plurality of mating grooves of the ring gear.
According to another embodiment, a ring and pinion gear set comprises a pinion gear and a ring gear. The pinion gear has a plurality of rolling elements. The plurality of rolling elements is disposed about at least a portion of a periphery of the pinion gear. Each of the plurality of rolling elements has a cage portion and a plurality of ball bearings secured by the cage portion. The ring gear has a plurality of mating grooves. The mating grooves have a complimentary shape relative to the ball bearings. The ball bearings of the rolling elements of the pinion gear are engageable with the mating grooves of the ring gear to transfer torque from the pinion gear to the ring gear.
According to a further embodiment, a pinion gear for a reduced friction ring and pinion gear set comprises a plurality of rolling elements. Each of the plurality of rolling elements has a cage portion and a plurality of ball bearings. The plurality of ball bearings is retained within the cage portion. The cage portion is joined to the pinion gear. The ball bearings of the rolling elements of the pinion gear are engageable with a plurality of corresponding mating grooves of the ring gear to transfer torque from the pinion gear to the ring gear.
While the rolling element 26 is depicted as being generally flat in
Turning back to
The slots 36 of the cage portion 28 of the pinion gear 22 allows the end ball bearings 32 to gradually transition into the mating groove 38 of the ring gear 24. The movement of the end ball bearings 32 additionally improves the alignment of the pinion gear 22 with the ring gear 24. Thus, the end ball bearings 32 of the pinion gear 22 are self-aligning with the mating groove 38 of the ring gear 24. This self-aligning aspect of the contact between the pinion gear 22 and the ring gear 24 allows for larger tolerances in the manufacturing and the assembly of ring and pinion gear set 20.
As contact between the pinion gear 22 and the ring gear 24 is a rolling contact between the bearings 30, 32 of the pinion gear 22 and the mating grooves 38 of the ring gear 24, noise of the ring and pinion gear set 20 is reduced compared to a traditional ring and pinion gear set 10. The reduction in noise may be attributed to a mating surface contact between the bearings 30, 32 and the mating grooves 38 of the ring and pinion gear set 20 compared to the teeth 16, 18 of the ring and pinion gear set 10. The slot 36 allows the end bearings 32 to gradually transition into the mating grooves 38, thereby reducing the noise of the ring and pinion gear set 20.
Additionally, the bearing 30, 32 contacting the mating grooves 38 reduces the susceptibility of damage to either the pinion gear 22 or the ring gear 24 of the ring and pinion gear set 20. The susceptibility of damage is reduced due to the gradual transition of the bearings 30, 32 into the mating grooves 38.
