Vehicle Headrest Locking Mechanism Parallel Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing retractable headrests for vehicle seats face challenges in securely locking the pivotal motion of the headrest frame due to structural limitations, making it difficult to maintain the locking member in a parallel position and engage it evenly with the pivot shaft.
Innovation Solution
A headrest design featuring a pivot shaft supported by the seatback frame, a locking mechanism with fixed and pivotal walls, and a bias spring that allows the locking member to be shortened and maintained in parallel with the pivot shaft, enabling secure locking of the headrest frame in the use position using a simple structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the locking member is designed to span the full interval between the open ends of the headrest frame, then it can provide sufficient locking strength, but it becomes difficult to maintain the locking member in a parallel position and engage it evenly with the pivot shaft
Solution Approach 1:
The locking mechanism is divided into multiple components: the locking member, fixed walls, pivotal walls, and bias spring. The locking member is positioned between the fixed walls rather than spanning the entire headrest frame width, allowing it to be shorter while still providing effective locking through the coordinated action of the segmented components.
Solution Approach 2:
The fixed walls and pivotal walls act as intermediary elements that mediate between the locking member and the headrest frame. These intermediary structures enable the locking member to engage effectively without needing to span the full width of the headrest frame, thus maintaining parallel alignment during engagement.
2Device complexity
If a simple locking structure is used, then the device complexity is reduced, but the reliability of locking the pivotal motion securely is compromised
Solution Approach 1:
The locking mechanism incorporates dynamic elements including the bias spring that automatically applies locking force, and the pivotal walls that can pivot to accommodate the locking member's movement. This dynamic design maintains simple structure while ensuring reliable locking through automatic spring-loaded engagement and adaptive pivotal motion.
Solution Approach 2:
The mechanism utilizes parameter changes in the form of spring force and pivotal angle adjustments. The bias spring changes its compressive force parameter to maintain reliable locking, while the pivotal walls change their angular parameter to accommodate the locking member's approach and engagement, achieving both simplicity and reliability.
3Ease of operation
If the locking member is shortened to less than the interval between the inner surfaces of the left and right ends of the headrest frame, then it can move easily while maintaining parallel alignment, but the locking span is reduced
Solution Approach 1:
The locking mechanism transitions from a one-dimensional spanning approach to a multi-dimensional engagement system. The locking member operates in the vertical dimension between fixed walls, while the pivotal walls provide angular adjustment capability, effectively utilizing multiple dimensions to achieve secure locking with a shorter locking member.
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 design allows for easy movement and secure locking of the headrest frame, ensuring it remains locked in the use position without wobbling, while maintaining a parallel alignment with the pivot shaft, thus addressing the structural limitations of previous designs.
Implementation Method 1
a bias spring that pivotally biases the headrest frame in a direction toward the retracted position
Data Source
AI summary
A headrest can be pivoted between a use state and a retracted state. The headrest has a pivot shaft pivotally supported to an upper part of a back frame. Opening ends of the headrest frame are connected to the pivot shaft. A locking mechanism is provided on the pivot shaft between the ends of the headrest frame. The lock mechanism includes right and left lateral wall portions into which the pivot shaft is inserted. Right and left lateral plate portions are connected to the pivot shaft between the right and left lateral wall portions. The headrest frame is pivotally biased toward the retracted position by a pivot member biasing spring. The locking mechanism may have a columnar member. The columnar member may approach the pivot shaft while maintaining a parallel state with the pivot shaft.