Integrally Forged Ring Gear Driveline Component

Solution Overview

Problem

Traditional power take-off units (PTUs) in all-wheel drive (AWD) vehicles require costly and time-consuming laser welding to secure the ring gear, which is complex and inefficient.

Innovation Solution

A power transfer device with a unitarily formed transfer member and support shaft, where the ring gear is forged as a single piece with a tubular portion, eliminating the need for welding by using an interference fit to secure the support shaft within the transfer member's bore.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If laser welding is used to secure the ring gear to the gear shaft, then the connection strength is improved, but the manufacturing cost and time increase

Engineering Contradiction:

Improveconnection strengthVSAvoidmanufacturing time

Core Design Contradiction:

StrengthVSLoss of time

Solution Approach 1:

The ring gear and drive member are merged into a single integrally formed component through forging, eliminating the separate welding operation. The unitary construction provides both strong connection and reduced manufacturing complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The welding process (thermal/mechanical system) is replaced with a forging process that creates an integral structure. The interference fit between the support shaft and bore provides the necessary mechanical connection without welding.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Strength

If laser welding is used to secure the ring gear to the gear shaft, then the connection strength is improved, but the manufacturing cost increases

Engineering Contradiction:

Improveconnection strengthVSAvoidmanufacturing cost

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The ring gear and drive member are merged into a single integrally formed component through forging, eliminating the separate welding operation. The unitary construction provides both strong connection and reduced manufacturing complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The complex and expensive welding process is replaced with a simpler, more cost-effective forging and interference fit approach. The integrally formed component achieves the same functional result at lower cost.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Stability of the object's composition

If the ring gear is fitted about the gear shaft and welded in place, then the structural integrity is improved, but the device complexity increases

Engineering Contradiction:

Improvestructural integrityVSAvoidassembly complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The ring gear and drive member are merged into a single integrally formed component through forging. This unitary construction maintains structural integrity while eliminating the complexity of separate components and assembly steps.

Inventive Principle:

Principle #5Merging (Combining)

4Adaptability or versatility

If traditional PTU with separate ring gear and gear shaft are used, then the adaptability is improved, but the productivity decreases

Engineering Contradiction:

Improvedesign flexibilityVSAvoidmanufacturing efficiency

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The ring gear and drive member are merged into a single integrally formed component through forging. This unitary construction maintains structural integrity while eliminating the complexity of separate components and assembly steps.

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

This solution simplifies the assembly process, reduces costs, and avoids high torque loads on the support shaft, enabling efficient power transmission without the need for complex welding.

Implementation Method 1

enables efficient power transmission without the need for complex welding

Methodology Applied

Scientific EffectInterference fit: Friction

Data Source

PatentUS10124451B2Driveline component having ring gear integrally formed with tubular drive member

Publication Date: 2018.11.13 AMERICAN AXLE & MANUFACTURING INC

AI summary

The present teachings provide for a power transfer device and method of forming a power transfer device that includes a unitarily formed transfer member and a support member. The transfer member can be supported within a housing for rotation about an input member and can be coupled to the input member to receive rotational power therefrom. A ring gear defined by the transfer member can meshingly engage with a pinion gear. The support member can be disposed concentrically about the input member and be rotatable about a first axis relative to the housing. The support member can have a first end and a second end. The first end of the support member can be supported for rotation relative to the housing by a support bearing. The second end of the support member can be received within a bore defined by the transfer member and fixedly coupled thereto for common rotation.