Motor-Vehicle Door Lock Coupling for Post-Crash Opening
Solution Overview
Problem
Existing motor-vehicle locks, particularly door locks, fail to reliably open after a crash, especially when the inertia lever does not transfer the coupling element into its uncoupled position, preventing occupants from escaping and complicating rescue efforts due to locked doors.
Innovation Solution
The coupling element can be controlled in two coupled positions, allowing differentiation between internal and external actuating levers, ensuring the internal actuating lever remains engaged with the release lever while the external actuating lever is disengaged during a crash, facilitating easy opening from the inside and outside post-crash.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the inertia lever transfers the coupling element into its uncoupled position during a crash, then the locking mechanism remains closed and the door remains closed for safety, but the door cannot be opened from the inside or outside after the crash
Solution Approach 1:
The actuating lever system is segmented into internal and external actuating levers with different coupling behaviors. The coupling element can be controlled in first and second coupled positions, allowing the internal actuating lever to remain engaged while the external actuating lever is disengaged during a crash. This segmentation enables differentiated crash response for different opening scenarios.
Solution Approach 2:
The coupling element's engagement state is made dynamic rather than static. It can switch between first coupled position (internal lever engaged) and second coupled position (external lever engaged), allowing the system to adapt its crash protection behavior based on which actuating lever is being used. This dynamic control resolves the contradiction by enabling post-crash opening while maintaining crash protection.
2Reliability
If the coupling element is in its uncoupled position, then action on the actuating lever comes to nothing and the locking mechanism remains closed, but this prevents intentional opening when needed
Solution Approach 1:
Different coupling behaviors are applied to different actuating levers. The internal actuating lever maintains engagement with the release lever through the coupling element in the first coupled position, while the external actuating lever is disengaged in the second coupled position. This local differentiation allows intentional opening from the inside while preventing accidental opening from the outside during a crash.
Solution Approach 2:
The coupling element's position parameter is changed to create distinct operational modes. By controlling the coupling element in first and second coupled positions, the system changes the engagement parameter between internal and external actuating levers, enabling adaptability in opening behavior while maintaining crash protection reliability.
3Reliability
If a control lever guided in a control contour of the inertia lever is provided, then the coupling behavior is defined and controlled, but the device complexity increases
Solution Approach 1:
The coupling element serves multiple functions: it controls engagement between the internal actuating lever and release lever, controls engagement between the external actuating lever and release lever, and responds to crash forces through the inertia lever. This multi-functionality eliminates the need for separate control levers for each actuating lever, reducing device complexity while maintaining reliable coupling behavior control.
Solution Approach 2:
The control functions for both internal and external actuating levers are merged into a single coupling element mechanism. Rather than having separate control levers for each actuating lever, the coupling element integrates both control functions, responding to crash forces through the inertia lever while controlling both lever engagements, thereby reducing the number of components.
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
Ensures easy and reliable opening of the vehicle door from the inside or outside after a crash, enhancing safety and functionality by maintaining internal lever engagement and preventing accidental opening from the outside.
Implementation Method 1
at least one inertia lever for forcing the coupling element into its uncoupled position at least in the event of a crash. The crash situation corresponds to high accelerations or transverse accelerations of generally 5 g and more
Data Source
AI summary
A motor-vehicle lock, in particular a motor-vehicle door lock, which is equipped with a locking mechanism made up substantially of a rotary latch and a safety catch. Also provided are at least one actuating lever and a release lever which, by means of a coupling element, can be engaged with one another in the at least one coupled position of said coupling element and can be disengaged from one another in the uncoupled position of the coupling element. Additionally provided is an inertia lever for forcing the coupling element into its uncoupled position at least in the event of a crash. According to the invention, depending on the design of the actuating lever, the coupling element can be moved in a controlled manner into a first coupled position and a second coupled position.