Adjustable Cam Locking Device for Double-Leaf Vehicle Door Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Double-leaf bus doors lack reliable locking mechanisms between the two door leaves, leading to potential opening due to stresses and deformations caused by static overdetermination and tolerances, which disrupt alignment with the vehicle's outer skin.
Innovation Solution
A locking device featuring a cam device with adjustable cams and a catch device, allowing for variable adjustment of the cam fastening position to reduce tension and ensure proper alignment, combined with a length-adjustable guide linkage for correct door alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fixed cam device is used for locking the door leaf, then the locking mechanism is simple and reliable, but stresses and deformations occur due to tolerances and static overdetermination, disrupting alignment with the vehicle's outer skin
Solution Approach 1:
The cam device is made adjustable along the longitudinal axis of the door leaf, allowing dynamic repositioning to compensate for manufacturing tolerances and static overdetermination. The cam can be positioned at different locations (e.g., closer to front or rear) to optimize alignment and reduce stresses in the locked state.
Solution Approach 2:
The position parameter of the cam device is made variable through an adjustment mechanism (such as a threaded rod or slots). This allows the cam's longitudinal position to be changed within a range, enabling compensation for tolerance accumulations and optimization of the locking geometry to maintain alignment precision.
2Device complexity
If the cam position is fixed during manufacturing, then the device complexity is low, but alignment between door leaf and outer skin is disrupted due to tolerances
Solution Approach 1:
A simple adjustment mechanism is introduced that allows the cam position to be varied along the longitudinal axis. This could be a threaded rod with a locking nut, or slots with adjustment holes, providing minimal complexity while enabling precise alignment compensation.
Solution Approach 2:
The adjustment mechanism is designed to be set during manufacturing or installation. The cam position can be preliminarily adjusted to compensate for known tolerance variations, ensuring proper alignment without requiring complex real-time control systems.
3Manufacturing precision
If adjustable cams are introduced to compensate for tolerances, then alignment precision is improved, but the device complexity increases
Solution Approach 1:
The adjustment mechanism changes only one critical parameter - the longitudinal position of the cam device. This single-degree-of-freedom adjustment is sufficient to compensate for tolerance accumulations while keeping the mechanism simple and maintainable.
Solution Approach 2:
The adjustment mechanism provides a simple, low-complexity way to make the cam position variable. Examples include a threaded rod with lock nut, or predetermined adjustment holes in slots, which add minimal complexity while enabling precise alignment.
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The invention relates to a locking device (10) for locking a door leaf (101), advantageously for a double-leaf vehicle door (100), in particular a vehicle outward-swinging door. The locking device (10) comprises a cam assembly (1) which has at least one cam (2) for locking with a catch (3). The cam assembly (1) is characterized in particular by an adjustment device (4) by means of which the locking position of the at least one cam (2) can be variably adjusted.