Planetary Belt Drive Steering Assist for Tight Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need to integrate electric motors into hydraulic steering systems of commercial vehicles to provide requisite torque for steering shaft rotation while meeting specific packaging requirements.
Innovation Solution
A system comprising a planetary gear set and belt drive system is used to apply steering shaft torque, utilizing a sun gear, ring gear, planetary carrier, and pulley belt to transfer torque from an electric motor to the steering shaft, ensuring robust torque multiplication and quiet operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If an electric motor is integrated into a hydraulic steering system to provide torque for steering shaft rotation, then steering assist capability is improved, but packaging space requirements become more constrained
Solution Approach 1:
The planetary gear set is nested within the steering system housing, with the sun gear, planetary gears, and ring gear arranged in a compact concentric configuration. The electric motor is positioned to drive the sun gear, and the entire planetary gear assembly is integrated into the existing steering column structure, allowing torque multiplication in a minimal volume.
Solution Approach 2:
The planetary gear set utilizes radial arrangement of gears around the sun gear, transforming the linear space requirement into a radial compact layout. The belt drive system connects the planetary carrier output shaft pulley to the steering shaft pulley through a compact routing path, efficiently utilizing three-dimensional space within the steering column.
2Power
If a planetary gear set with belt drive is used to transfer torque from electric motor to steering shaft, then torque multiplication is improved, but system complexity increases
Solution Approach 1:
The planetary gear set and belt drive system are merged into a single integrated torque transmission assembly. The planetary carrier output shaft is directly coupled to the planetary carrier output shaft pulley, and the steering shaft pulley is directly coupled to the steering shaft, eliminating intermediate coupling components and simplifying the overall system architecture.
Solution Approach 2:
The planetary gear set serves multiple functions: it provides torque multiplication from the electric motor, accommodates the belt drive system for flexible power transmission, and integrates with the existing steering column structure. The housing encloses all components while providing structural support and alignment.
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 system enhances driver comfort by reducing effort under high axle loads and meets space constraints within commercial vehicles, providing a smooth and responsive steering experience.
Implementation Method 1
a planetary gear set comprising: a sun gear, a ring gear disposed radially outward in a radial direction with respect to the sun gear, and a planetary carrier comprising a plurality of planetary gears
Implementation Method 2
robust torque multiplication
Implementation Method 3
a pulley belt disposed at least partially around the planetary carrier output shaft pulley and at least partially around the steering shaft pulley
Implementation Method 4
a planetary carrier output shaft pulley concentrically disposed on the planetary carrier output shaft, a steering shaft pulley disposed radially adjacent to the planetary carrier output shaft pulley
Data Source
AI summary
A system for rotating a steering shaft of a vehicle, the steering shaft extending in a longitudinal direction, includes: a planetary gear set including: a sun gear, a ring gear disposed radially outward in a radial direction with respect to the sun gear, and a planetary carrier comprising a plurality of planetary gears and a planetary carrier output shaft, each planetary gear of the plurality of planetary gears being rotatable within the planetary carrier, in radially outward rotating engagement with the ring gear, and in radially inward rotating engagement with the sun gear; a belt drive system including: a planetary carrier output shaft pulley concentrically disposed on the planetary carrier output shaft, a steering shaft pulley disposed radially adjacent to the planetary carrier output shaft pulley, and a pulley belt disposed at least partially around the planetary carrier output shaft pulley and at least partially around the steering shaft pulley.