Low-friction wheel-hub sealing assembly with keyed conical mounting
Solution Overview
Problem
Sealing assemblies for wheel-hub units experience increased friction due to axial displacement and deformation of rotating screens, leading to potential damage and interference with rolling bearings, especially during bending maneuvers.
Innovation Solution
A low-friction sealing assembly with a screen having a cylindrical or conical sleeve portion and a radially projecting flange, where the sleeve is keyed into a mounting seat with a conical entry edge and radial thickness to prevent plastic deformation, ensuring stable engagement and minimal friction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If an axial stop is provided to lock the screen in position, then the screen is axially locked, but the screen must pass beyond the axial stop during mounting which causes plastic deformation and loosening of the engaging connection
Solution Approach 1:
The mounting seat is segmented into two functional zones: an axial stop region for positioning and a keyed engagement region for secure mounting. The keyway in the screen and corresponding key on the conical surface create a separate engagement mechanism that operates independently from the axial stop, allowing the screen to be locked axially without requiring forced passage that causes deformation.
Solution Approach 2:
A key element acts as an intermediary between the screen and the mounting seat. This key fits into a keyway on the conical surface of the screen and engages with the keyed portion of the mounting seat, providing a mediating mechanism that secures the screen without requiring it to deform plastically during installation.
2Stability of the object's composition
If the screen is mounted with tight engagement to prevent rotation, then rotational stability is improved, but friction increases due to interference between sealing lips and rotating components
Solution Approach 1:
The engagement system transitions from a static interference fit to a dynamic keyed connection. The key and keyway mechanism allows the screen to be securely attached without continuous interference contact, reducing friction while maintaining rotational stability through the keyed engagement that prevents relative rotation between the screen and mounting seat.
3Volume of moving object
If the screen dimensions are reduced to fit within the mounting seat, then the assembly compactness is improved, but the screen becomes more susceptible to plastic deformation during mounting
Solution Approach 1:
The conical keyed surface is designed with preliminary geometric features that guide the screen into proper alignment and distribution of mounting forces before final engagement. The keyway geometry is pre-configured to receive the mounting key in a way that distributes stress evenly across the screen material, preventing localized plastic deformation even when the screen has compact dimensions.
Data Source
AI summary
Low-friction sealing assembly for a vehicle wheel-hub unit to be inserted in an annular space defined between a flanged rotating element and a stationary element, to protect at least one ring of rolling members arranged between the stationary element and the rotating element; the flanged rotating element being provided with a flange and a mounting seat delimited by a cylindrical bottom wall and by an axial shoulder arranged on the opposite side to the flange. Nominal dimensions of an internal diameter of a sleeve portion of an annular screen are substantially the same as nominal dimensions of an outer diameter of a cylindrical bottom wall of the mounting seat, and the axial shoulder has an entry edge with a substantially conical form for facilitating mounting of the annular screen on the rotating annular element.