Ring Gear Sawtooth Profile Alignment

Solution Overview

Problem

Ring gears bonded to differential housings via weld or interference fit often suffer from misalignment, leading to undesirable wear on the pinion gear and unwanted noise.

Innovation Solution

A differential housing design featuring a ring gear support member with a sawtooth profile on its inner annular surface, facilitating proper alignment and an interference fit with the differential housing, ensuring accurate positioning and secure mounting of the ring gear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the ring gear is bonded to the differential housing through weld or interference fit, then the ring gear is securely mounted, but misalignment occurs leading to undesirable wear and noise

Engineering Contradiction:

Improvemounting securityVSAvoidalignment accuracy

Core Design Contradiction:

StrengthVSManufacturing precision

Solution Approach 1:

The sawtooth profile is pre-formed on the ring gear's inner annular surface before assembly. This preliminary geometric feature guides the ring gear into proper alignment with the differential housing body during the interference fit process, preventing misalignment before the bonding operation completes.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The sawtooth profile acts as an intermediary alignment mechanism between the ring gear and the differential housing body. The tapered teeth of the sawtooth profile engage with corresponding features in the body, serving as a mechanical mediator that ensures precise angular and radial alignment during the interference fit mounting process.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Strength

If the ring gear is mounted with interference fit, then secure bonding is achieved, but misalignment during assembly causes undesirable wear on the pinion gear

Engineering Contradiction:

Improvebond strengthVSAvoidwear resistance

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The sawtooth profile is pre-formed on the ring gear's inner annular surface before assembly. This preliminary geometric feature guides the ring gear into proper alignment with the differential housing body during the interference fit process, preventing misalignment before the bonding operation completes.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The sawtooth profile acts as an intermediary alignment mechanism between the ring gear and the differential housing body. The tapered teeth of the sawtooth profile engage with corresponding features in the body, serving as a mechanical mediator that ensures precise angular and radial alignment during the interference fit mounting process.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Strength

If the ring gear is mounted with interference fit, then secure bonding is achieved, but misalignment creates unwanted noise

Engineering Contradiction:

Improvebond strengthVSAvoidnoise

Core Design Contradiction:

StrengthVSObject-generated harmful factors

Solution Approach 1:

The sawtooth profile is pre-formed on the ring gear's inner annular surface before assembly. This preliminary geometric feature guides the ring gear into proper alignment with the differential housing body during the interference fit process, preventing misalignment before the bonding operation completes.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The sawtooth profile acts as an intermediary alignment mechanism between the ring gear and the differential housing body. The tapered teeth of the sawtooth profile engage with corresponding features in the body, serving as a mechanical mediator that ensures precise angular and radial alignment during the interference fit mounting process.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 sawtooth profile significantly reduces installation errors and misalignment, resulting in reduced wear and noise, enhancing the operational reliability and performance of the differential system.

Implementation Method 1

The first region includes a sawtooth profile to establish a desired alignment of the ring gear and the body

Methodology Applied

Scientific EffectMechanical engagement: Mechanical Fastener

Implementation Method 2

the second region facilitating an interference fit with the ring gear support surface

Methodology Applied

Scientific EffectInterference fit: Friction

Data Source

PatentUS10487932B2Vehicle differential

Publication Date: 2019.11.26 GM GLOBAL TECHNOLOGY OPERATIONS LLC

AI summary

A differential housing includes a body including an outer surface. The body has a first end, a second end, and an intermediate portion extending therebetween. A ring gear support member extends outwardly of the body at the second end. A ring gear support surface forms a first section of the intermediate portion. The ring gear support surface defines a first outer diameter of the intermediate portion. A ring gear is mounted to the outer surface of the body. The ring gear includes an inner annular surface having a first region defining a first inner diameter and a second region defining a second inner diameter. The first region includes a sawtooth profile to establish a desired alignment of the ring gear and the body and the second region facilitating an interference fit with the ring gear support surface.