Recirculating-Ball Steering Transmission for Compact Torque Assist
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulic power steering systems in utility vehicles are inefficient in terms of energy usage and costly to implement, with separate components requiring extensive installation and testing, leading to increased space and maintenance requirements.
Innovation Solution
An electromechanical steering system incorporating a servo transmission unit, such as a planetary or eccentric servo transmission, connected to a recirculating-ball steering transmission, driven by an electric motor, which reduces installation space and component count, and includes a ball nut with a linear guide device to absorb radial loads, providing a space-saving and reliable torque transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a hydraulic power steering system is used, then steering force is provided, but energy efficiency deteriorates due to high volumetric flow requirements
Solution Approach 1:
The patent replaces the hydraulic power steering system with an electromechanical steering system that uses an electric motor and recirculating-ball transmission to provide steering assistance, eliminating the need for hydraulic fluid and pumps, thereby significantly improving energy efficiency and reducing energy loss
2Ease of manufacture
If a hydraulic power steering system with separate components is used, then steering function is provided, but device complexity increases due to multiple lines and components requiring installation and testing
Solution Approach 1:
The patent integrates the electric motor, servo transmission, and recirculating-ball transmission into a single integrated electromechanical steering system, eliminating the need for separate hydraulic lines, pumps, and reservoirs, thereby reducing installation complexity and assembly steps
Solution Approach 2:
The recirculating-ball transmission serves multiple functions including torque multiplication, steering assistance, and mechanical linkage between the steering wheel and steering mechanism, reducing the need for separate components
3Power
If a conventional planetary servo transmission with two transmission stages is used, then torque transmission is achieved, but installation space requirement increases
Solution Approach 1:
The patent divides the transmission system into two distinct stages: a servo transmission stage for torque multiplication and a recirculating-ball transmission stage for further torque multiplication and steering control. This segmentation allows for more compact arrangement and optimized space utilization compared to a conventional two-stage planetary transmission
4Ease of manufacture
If a conventional two-stage planetary transmission is used, then torque transmission is achieved, but manufacturing cost increases due to reduced number of gearwheels
Solution Approach 1:
The patent merges the servo transmission and angle transmission functions into an integrated recirculating-ball transmission system, reducing the total number of gearwheels and transmission components while maintaining adequate torque transmission capability for the steering application
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 solution results in a more energy-efficient, cost-effective, and reliable steering system with reduced maintenance needs, offering improved torque transmission and operational stability.
Implementation Method 1
a ball nut with a linear guide device to absorb radial loads
Implementation Method 2
a mechanically driven recirculating-ball transmission with a ball nut which is engaged with a segment shaft
Data Source
AI summary
A steering transmission for an electro-mechanical steering system for a vehicle includes an electric motor, a servo transmission, and an angle transmission for connecting a steering column of the steering system to a control stalk of the steering system. The angle transmission is a mechanically driven recirculating-ball transmission with a ball nut, which is engaged with a segment shaft of the steering transmission that is/can be connected to the steering stalk. A spindle of the recirculating-ball transmission is continuous. The spindle is connected to an output shaft of the servo transmission on one side. The servo transmission is/can be driven by the electric motor.