Hyundai WIA has been granted a patent for a constant velocity joint for vehicles. The joint includes an axle housing fixed to a knuckle by a hub bearing, with a joint assembly transmitting power from a shaft to the axle housing through joint balls. The joint also features an extension portion that provides a pressing force to the hub bearing’s inner race, and a boot that forms a restraining force between the extension portion and the boot in the axial direction. GlobalData’s report on Hyundai WIA gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Hyundai WIA, EV integrated thermal management was a key innovation area identified from patents. Hyundai WIA's grant share as of September 2023 was 23%. Grant share is based on the ratio of number of grants to total number of patents.
Constant velocity joint with extended axle housing and boot
A recently granted patent (Publication Number: US11773912B2) describes a constant velocity joint for a vehicle. The joint includes an axle housing fixed to a knuckle by a hub bearing, a joint assembly that transmits power from a shaft to the axle housing through joint balls, and an extension portion that provides a pressing force to an inner race of the hub bearing in the axial direction of the axle housing.
The joint also includes a boot that surrounds the extension portion and forms a restraining force between the extension portion and the boot in the axial direction. The boot has multiple contact portions, including a first contact portion that contacts the end portion of the extension portion, a second contact portion that contacts the outermost side of a protrusion on the extension portion, and a third contact portion that contacts the protrusion on the outward side of the vehicle body to form an inner groove into which the protrusion is inserted.
In one embodiment, the end portion of the axle housing on the inward side of the vehicle body is deformed to extend outwardly in the radial direction, and the outer diameter of the protrusion is greater than the outer diameter of the end portion of the inner race on the inward side of the vehicle body. This configuration allows the extension portion to press the end portion of the inner race in the axial direction, fixing the inner race securely.
To further secure the boot and prevent it from escaping, a band is fastened onto the outer side of the boot. The boot has a band fastening groove formed in its outer side to accommodate the band. The position of the band fastening groove is within a specific range relative to the end portion of the extension portion on the inward side of the vehicle body.
The patent also describes additional ranges for the outer diameter of the protrusion, the axial-direction width of the band, and the axial-direction thickness of the extension portion to ensure secure assembly and sufficient sealability of the joint.
Overall, this patent presents a constant velocity joint design for vehicles that provides improved stability and secure assembly, enhancing the performance and reliability of the joint.