Wheel Hub Anti-Loosening Assembly for Single-Nut Torque Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

High-performance motor-vehicle wheel fastening systems face issues with loosening or over-tightening due to driving and braking torque, particularly in single-nut fastening systems, leading to anomalies and inefficiencies in wheel assembly.

Innovation Solution

An anti-loosening device comprising a gear with outer teeth engaging inner teeth of the wheel hub, combined with an elastic element and a coupling element, which aligns with an anti-rotation sector of the single-nut fastening unit to prevent loosening or over-tightening, utilizing a simple and low-cost design for both sides of the vehicle.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a single-nut fastening system is used to reduce wheel change time, then productivity is improved, but the fastening unit becomes prone to loosening or over-tightening due to driving and braking torque

Engineering Contradiction:
Improvewheel change timeVSAvoidfastening stability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The anti-loosening device applies a preliminary counteracting force through its elastic element and gear mechanism that opposes the loosening torque generated during vehicle operation. The device is pre-configured to engage with the fastening unit and automatically counteract the harmful effects of driving and braking torques before significant loosening occurs, thereby maintaining fastening reliability while preserving the speed advantage of single-nut systems

Inventive Principle:
Principle #9Preliminary anti-action

2Reliability

If traditional multi-fastening systems are used to prevent loosening, then fastening stability is improved, but the time required to change wheels increases

Engineering Contradiction:
Improvefastening stabilityVSAvoidwheel change time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The solution segments the fastening system into two independent functional components: a single fastening nut for rapid installation and removal, and a separate anti-loosening device with gear mechanism that provides stabilization. This segmentation allows the fastening operation to remain quick while the anti-loosening device independently handles the stability function, avoiding the time penalty of multiple fasteners

Inventive Principle:
Principle #1Segmentation

3Reliability

If an anti-loosening device is added to a single-nut system, then fastening stability is improved, but device complexity increases

Engineering Contradiction:
Improvefastening stabilityVSAvoidfastening system structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The anti-loosening device merges multiple functions into a single integrated mechanism: the gear element engages with the fastening unit's anti-rotation sector, the elastic element provides both forcing and return actions, and the coupling element synchronizes the anti-loosening action with the fastening operation. This merging reduces overall system complexity compared to using separate components for each function

Inventive Principle:
Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The anti-loosening device effectively minimizes anomalies caused by torque effects, ensuring stable coupling and easy implementation across both drive and non-drive wheels, while maintaining a lightweight and cost-effective solution.

Implementation Method 1

an elastic element (5) extending axially with respect to said gear (3) within said wheel hub (H), wherein the elastic element (5) comprises a first end (6) connected to said gear (3), and a second end (7) engaged against at least one abutment and centering surface obtained inside the wheel hub (H)

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3909784B1Motor-vehicle wheel assembly with an Anti-loosening device
Publication Date: 2024.02.21 STELLANTIS EUROPE SPA
  • EP3909784B1 patent drawingFigure 1
  • EP3909784B1 patent drawingFigure 2
  • EP3909784B1 patent drawingFigure 3

AI summary

An anti-loosening device (1) for a fastening unit (2) of a motor-vehicle wheel (W) is described here, wherein the motor-vehicle wheel (W) is configured to be coupled with a wheel hub (H) by means of the fastening unit (2). The anti-loosening device (1) is configured to be arranged within the wheel hub (H) along an axial direction, so that a main axis of the anti-loosening device (1) coincides with the wheel axis (W). The anti-loosening device (1) comprises: - a gear (3) arranged to cooperate with inner teeth (H3) of the wheel hub (H), - an elastic element (5) extending axially with respect to the gear (3), and - a coupling element (8) obtained on a sector of said gear (3), arranged to receive a corresponding fastening member (10), During assembly of the wheel (W) - hub (H) assembly, the anti-loosening device (1) is arranged to create a compressed configuration, wherein the gear (3) is decoupled with respect to the inner teeth (H3), and is arranged within a cavity portion (16) obtained on the inner surface (H2) of the wheel hub (H), so as to allow rotation of the anti-loosening device (1) around the main axis; Following a rotation of the anti-loosening device (1), the coupling element (8) is arranged to be radially aligned with respect to an anti-rotation sector (9) obtained on the fastening unit (2), in such a way that in the final assembled condition, the fastening member (10) coupled to the coupling element (8) cooperates with the anti-rotation sector (9), to avoid loosening of the locking unit (2).