Steering Rack Locking Device for Impact Energy Restriction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During a small front bumper overlap impact, a significant portion of the impact energy is directed into the front wheel and steering system, causing unwanted rotation and potentially reducing the effectiveness of supplemental restraints within the steering wheel.
Innovation Solution
A vehicle system featuring a steering rack assembly with a locking device that can transition between a deactivated and activated configuration, restricting the translation of the steering rack and column assembly based on detected rotational speeds and decelerations, thereby preventing excessive rotation of the front wheel and steering wheel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the steering rack is allowed to translate freely during impact, then the steering system can absorb some impact energy through controlled movement, but excessive rotation of the front wheel and steering wheel occurs, reducing the effectiveness of supplemental restraints
Solution Approach 1:
The locking device transitions from a static fixed state to a dynamic controlled state. During normal operation, the rack translates freely for normal steering. During impact detection (via rotational speed threshold), the locking device activates to restrict rack translation, dynamically adapting the system behavior based on operating conditions.
Solution Approach 2:
The system uses rotational speed sensors to detect steering wheel rotation during impact and provides feedback to the control unit. The control unit processes this feedback and activates the locking device when the rotational speed exceeds a predetermined threshold, creating a closed-loop control system that responds to actual impact conditions.
2Reliability
If a locking device is introduced to restrict rack translation during impact, then the effectiveness of supplemental restraints is maintained, but the device complexity of the steering system increases
Solution Approach 1:
The locking device is integrated into the existing steering rack assembly structure, serving multiple functions: normal steering operation when deactivated, impact energy restriction when activated, and structural integration with the rack and pinion gear. The control unit also serves dual purposes for normal steering control and impact detection.
Solution Approach 2:
The locking device acts as an intermediary mechanism between the rack and the vehicle body. It selectively engages to transmit or restrict forces between the rack and chassis based on impact conditions, mediating the energy transfer without requiring complete system redesign.
3Reliability
If the locking device activates quickly to restrict rotation, then the supplemental restraints remain effective, but the response time and precision of activation control must be precisely managed
Solution Approach 1:
The system pre-establishes a rotational speed threshold that, when exceeded, triggers locking device activation. This preliminary设定 of activation criteria allows the system to respond automatically and consistently to impact conditions without requiring complex real-time analysis during the impact event.
Data Source
AI summary
Vehicles and vehicle systems including locking devices are disclosed herein. In one embodiment, a vehicle includes a front wheel, a steering rack assembly that includes a rack coupled to the front wheel, where the rack extends in a vehicle lateral direction and is translatable with respect to a unibody of the vehicle in the vehicle lateral direction, and a locking device coupled to the steering rack assembly, where the locking device includes a deactivated configuration that allows translation of the rack and an activated configuration that restricts translation of the rack.