Rotary Pawl Glove Box Latch Minimizing Envelope Size
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing slam to close, rotary pawl latches in vehicles have issues with large envelope size, multiple components, excessive biasing springs, and noise/vibration due to increased use of plastics, which affect durability and ease of operation.
Innovation Solution
A compact slam to close glove box latch design with a housing, paddle structure, rotary pawl, and lock plate, utilizing two torsion springs for biasing and interference-friction mechanisms to minimize components and noise, featuring a raised pivot point for reduced volume and snap-in assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple plastic components and biasing springs are used in the latch, then the latch can achieve slam to close functionality and hold under vibration, but the envelope size increases and manufacturing complexity increases
Solution Approach 1:
The patent combines multiple functions into fewer components. The rotary pawl integrates the locking mechanism and vibration resistance features. The single biasing spring provides both the slam-to-close force and the hold-under-vibration capability. The handle lever integrates the user interface and actuation mechanism, eliminating the need for separate components for each function.
Solution Approach 2:
The rotary pawl serves multiple functions: it provides the locking action, resists vibration through its rotary engagement with the striker, and works with the single biasing spring to achieve both slam-to-close and hold capabilities. This multi-functionality reduces the overall component count and envelope size while maintaining reliability.
2Adaptability or versatility
If multiple plastic components are used in the latch, then the latch can be molded with complex geometries for functionality, but manufacturing costs increase and production complexity increases
Solution Approach 1:
The patent reduces component count by merging functions into fewer parts that can be molded with complex geometries. The rotary pawl, handle lever, and lock plate are designed as integrated components with built-in features (guideways, engagement surfaces, spring mounting) that eliminate the need for separate fasteners, bearings, and adjustment mechanisms, thereby reducing assembly steps and manufacturing cost.
3Ease of manufacture
If plastic materials are used instead of metal, then manufacturing cost decreases and corrosion resistance improves, but wear and fatigue resistance deteriorates
Solution Approach 1:
The patent uses plastic materials with characteristics optimized for durability. The rotary pawl and handle lever are molded from plastics that balance cost, corrosion resistance, and wear/fatigue resistance. The design incorporates features that distribute stresses and reduce wear points, such as the rotary engagement between the pawl and striker, which allows controlled movement and prevents stress concentration.
4Ease of operation
If the pivot point is located below the panel face, then the handle can be pulled outward above the panel, but the latch envelope size increases
Solution Approach 1:
The patent uses a gooseneck-shaped handle lever that extends above the panel face while the pivot point remains below. This creates a spatial arrangement where the handle operates in a different dimension (above the panel) while the mounting footprint remains compact (below the panel), effectively reducing the latch envelope size while maintaining accessibility.
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 achieves a minimized envelope size, reduced noise, and improved durability by using fewer components and springs, ensuring the latch remains closed under vibration and slam conditions while being easy to assemble and operate.
Implementation Method 1
The rotary pawl is spring biased with a loop-style torsion spring to the open position.
Implementation Method 2
The rotary pawl is spring biased with a loop-style torsion spring to the open position.
Implementation Method 3
The paddle structure is spring biased with a torsion spring to the closed position.
Implementation Method 4
The paddle structure is spring biased with a torsion spring to the closed position.
Implementation Method 5
the lock plate is carried to an interference-friction position with the pawl. This interference-friction position fixes the position of both the pawl and the lock plate.
Data Source
AI summary
A slam to close, glove box latch includes a housing, a paddle structure connected to rotate on the housing, a rotary pawl mounted to rotate in the housing, and a lock plate carried by the paddle structure to selectively engage the rotary pawl to inhibit its movement. The rotary pawl is spring biased to the open position. The paddle structure is spring biased to the closed position. The paddle structure includes guideways in which the lock plate operates. When the paddle is moved to the open position, the pawl is released to rotate open and the lock plate is carried to an interference-friction position with the pawl whereby the paddle is held in the open position. When the pawl is closed by the slam action of the latch, the interference-friction with the lock plate is released and the paddle structure returns to the closed position. Biasing is limited to two springs. The volume (envelope) of the latch is minimized.