Vehicle Propeller Shaft Adapter Breakage for Impact Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional propeller shafts for vehicles face challenges in effectively absorbing impact energy during collisions, leading to potential breakage and injury due to the trade-off between strength for power transmission and impact absorption, with existing designs either compromising on strength or increasing weight and damage.
Innovation Solution
A propeller shaft design featuring a tube yoke and main tube connected via an adapter with tapered splines that break at a predetermined notch upon impact, allowing efficient separation and absorption of impact energy, while maintaining power transmission capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the front main tube includes a small-diameter portion and a large-diameter portion to absorb impact energy through compression, then impact energy absorption is improved, but the strength required for power transmission decreases
Solution Approach 1:
The front main tube is segmented into a small-diameter portion and a large-diameter portion, creating distinct functional zones. The small-diameter portion absorbs impact energy through compression deformation, while the large-diameter portion maintains structural strength for power transmission. This segmentation allows each portion to optimize its specific function without compromising the other.
Solution Approach 2:
Different diameter portions are created at different locations of the front main tube to provide locally optimized properties. The small-diameter portion at the front end provides impact absorption capability, while the large-diameter portion provides structural strength. This local quality variation resolves the contradiction between impact absorption and power transmission strength.
2Strength
If the overall diameter of the front main tube is increased to prevent strength decrease, then power transmission strength is maintained, but weight increases and layout becomes disadvantageous
Solution Approach 1:
Instead of uniformly increasing the diameter of the entire front main tube, the design segments the tube into portions with different diameters. Only the necessary large-diameter portion maintains increased diameter for strength, while other portions can have reduced diameters, thereby reducing overall weight and improving layout without sacrificing required strength.
3Strength
If the connecting portion between tube yoke and front main tube is integrally formed through friction welding, then connection strength is improved, but impact energy absorption capability decreases
Solution Approach 1:
The connecting portion is segmented into an integral portion (for normal operation strength) and a separable portion (for impact energy absorption). The separable portion is designed to separate under impact conditions, allowing impact energy absorption while the integral portion maintains connection strength during normal power transmission operations.
4Power
If tapered splines are formed at contact regions between tube yoke and main tube, then power transmission efficiency is improved, but device complexity increases
Solution Approach 1:
The tapered splines merge the functions of power transmission and connection between the tube yoke and main tube. By forming splines at the contact regions, the design combines the joining function with the power transmission function, improving power transmission efficiency without requiring additional separate components, thus limiting the increase in device complexity.
Data Source
AI summary
A propeller shaft for a vehicle in which a tube yoke is connected to a main tube via an adapter and tapered splines are formed at the contact regions between a tube yoke and the main tube to transmit the power output from a transmission to a rear wheel. The tube yoke and the main tube are displaced relative to each other at the tapered splines to break the adapter. The tube yoke and the main tube are thus separated from each other by virtue of the breakage of the adapter.