Vehicle Seat Tray Table Impact Retraction Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tray tables in vehicles do not effectively retract during decelerating impacts, such as frontal collisions, which can lead to potential injuries from collisions with the table.
Innovation Solution
A rotationally operable tray table in a vehicle seatback is actuated by an actuator that applies a downward force to bias the tray table toward the seatback surface upon impact, using a cable assembly and pulley mechanism to translate the force into a lateral motion, ensuring the tray table is safely retracted before the occupant moves forward.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the tray table is made rotationally operable between multiple positions, then the ease of operation and versatility are improved, but the reliability during impact is worsened because the tray table cannot effectively retract during decelerating impacts
Solution Approach 1:
The actuator is pre-configured to automatically activate upon detecting decelerating impact, moving the tray table to its retracted safety position before the occupant can move forward and collide with it. This preliminary action prevents the harmful effect of collision while maintaining the tray table's operational versatility during normal conditions.
2Reliability
If an actuator is added to move the tray table to safety position during impact, then the reliability during impact is improved, but the device complexity increases
Solution Approach 1:
A cable assembly with pulley mechanism serves as an intermediary between the actuator and the tray table. This intermediary translates the actuator's downward linear motion into the lateral motion required to move the tray table to its retracted safety position, enabling complex motion transformation while keeping the actuator itself relatively simple.
Solution Approach 2:
The patent replaces a potentially complex direct mechanical linkage system with a cable-pulley mechanism. This substitution simplifies the overall system by using flexible cables and simple pulleys instead of rigid linkages with multiple joints and constraints, reducing mechanical complexity while achieving the same functional result.
3Ease of operation
If a cable assembly and pulley mechanism are used to translate downward force into lateral motion, then the ease of operation is improved by enabling automatic tray table retraction, but the device complexity increases
Solution Approach 1:
The cable assembly and pulley mechanism act as an intermediary that automatically translates the actuator's downward force into lateral motion of the tray table during impact. This intermediary enables automatic retraction without requiring complex control systems, sensors, or programming, maintaining ease of operation through passive mechanical response to impact forces.
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 tray table is reliably moved into a safety position within fractions of a second during a decelerating impact, preventing collisions with the occupant and enhancing safety by being out of the way during the impact.
Implementation Method 1
the actuator applies a generally downward force that biases the tray table toward a safety position
Implementation Method 2
the actuator applies a generally downward force that biases the tray table toward a safety position
Implementation Method 3
using a cable assembly and pulley mechanism to translate the force into a lateral motion
Data Source
AI summary
A vehicle includes a seatback having a rear-mounted and rotationally operable tray table selectively operable between a plurality of rotational positions. An actuator is coupled to the seatback and the tray table, wherein in response to a decelerating impact, the actuator applies a generally downward force that biases the tray table toward a safety position against a back surface of the seatback.