Offset CV Joint Steering Drive for Agricultural Vehicles

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing single-suspended-wheel-steering drive systems for agricultural vehicles, such as tractors, are limited by their steering angles, which restrict the vehicle's ability to navigate tight curves due to the constraints of the constant velocity joint's working angle, leading to inefficient steering and shock absorption.

Innovation Solution

The system incorporates a wheel carrier with a shock absorber group and a drive group featuring a constant velocity joint with an offset center of rotation, allowing for a greater steering angle by incorporating a sliding end that translates longitudinally within a bell-shaped element, enabling both shock absorption and increased steering capability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a constant velocity joint is used in the drive group, then reliable motion transmission is achieved, but the steering angle is limited by the working angle of the joint

Engineering Contradiction:
Improvemotion transmission reliabilityVSAvoidsteering angle
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent introduces a sliding end that translates longitudinally within the bell-shaped element, adding a linear dimension of motion to the rotational motion of the constant velocity joint. This dimensional change allows the steering angle to exceed the working angle limitation of the joint while maintaining reliable motion transmission through the combined sliding and rotating mechanisms.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The sliding end acts as an intermediary between the constant velocity joint and the wheel carrier. It translates the rotational motion of the joint into combined sliding and rotational motion, enabling the wheel carrier to achieve steering angles greater than the joint's working angle while the joint itself remains within its reliable operating range.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the steering angle is increased beyond the constant velocity joint's working angle, then tighter curve navigation is enabled, but the joint cannot maintain constant velocity transmission

Engineering Contradiction:
Improvesteering angleVSAvoidconstant velocity transmission
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

By adding the longitudinal sliding dimension within the bell-shaped element, the system decouples the steering angle from the constant velocity joint's rotation angle. The sliding end can translate to accommodate larger steering angles while the joint maintains its constant velocity transmission within its working angle, resolving the contradiction between steering capability and transmission reliability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Device complexity

If a rigid axle solution is used, then structural simplicity is achieved, but the vehicle cannot handle situations where three wheels are on ground and one is raised

Engineering Contradiction:
Improveaxle structureVSAvoidwheel ground contact adaptability
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent segments the wheel support system into independent wheel carriers, each with its own shock absorber group and drive group connection. This segmentation allows each wheel to independently adapt to ground contact conditions, enabling the vehicle to operate with three wheels on ground and one raised, while maintaining a relatively simple overall structure compared to fully independent suspension systems.

Inventive Principle:
Principle #1Segmentation

4Volume of moving object

If the drive group is connected directly to the wheel carrier, then compact design is achieved, but the steering angle is constrained by the drive group features

Engineering Contradiction:
Improvedrive system volumeVSAvoidsteering angle
Core Design Contradiction:
Volume of moving objectVSEase of operation

Solution Approach 1:

The sliding end's longitudinal translation within the bell-shaped element adds a linear dimension to the compact drive group design. This allows the system to maintain a compact volume while achieving greater steering angles, as the sliding mechanism provides additional motion capability without significantly increasing the overall footprint of the drive group.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3504078B1Single-suspended-wheel-steering drive system
Publication Date: 2022.02.16 SAME DEUTZ FAHR ITAL SPA
  • EP3504078B1 patent drawingFigure 1
  • EP3504078B1 patent drawingFigure 2
  • EP3504078B1 patent drawingFigure 2a

AI summary

A single-suspended-wheel-steering drive system (1) connectable to a wheel group of a vehicle (900) for agricultural use. The system (1) comprises a wheel carrier (2) for the wheel group and a shock absorber group (3), to which the wheel carrier (2) is constrained in rotation around a steering axis (S-S). The system (1) further comprises a drive group (5) suitable to transmit the motion induced by the vehicle's transmission means to the wheel group. The drive group (5) comprises a drive shaft (51) operatively connected to the transmission means of the vehicle, a rotation shaft (52) for the rotation of the wheel group interconnected by a constant velocity joint (55), wherein such constant velocity joint (55) has a center of rotation (Cr) offset distally from said steering axis (S-S).