Motor Vehicle Door Lock with Segmented Pawl Motion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Motor vehicle door locking mechanisms experience noise issues due to pre-stress from tailgate seals and rattling noises from locking elements, which affect comfort and require powerful motors to operate effectively.
Innovation Solution
A door locking mechanism with a lever-like signal element and immobilization element that ensures the locking pawl remains engaged with the rotary latch during opening, reducing pre-stress by controlled motion and minimizing noise through a tangential and radial movement sequence, allowing a low-power motor to operate efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the locking pawl is spring-loaded and pre-stressed in the direction of the locking position, then the locking engagement is secure and reliable, but the motor requires higher power to overcome the spring force during opening
Solution Approach 1:
The spring element is configured to apply pre-stress to the locking pawl only in the engagement position, not throughout the entire movement range. This preliminary action secures reliable locking when engaged, while allowing the pawl to move more freely during the opening sequence, reducing the power needed by the motor.
Solution Approach 2:
The opening process is divided into distinct phases: first the locking pawl moves tangentially while remaining engaged with the rotary latch (relieving pre-stress), then radially outward to disengage. This segmentation allows the spring force to be overcome in controlled stages rather than all at once, reducing peak motor power requirements.
2Reliability
If the locking element is held in a motion-inhibiting and clamping manner by the rotary latch, then the locking security is improved, but rattling noises occur due to intended tolerances
Solution Approach 1:
The immobilization element is specifically designed to contact and clamp the locking element only in the locked position, providing localized stabilization where needed. This local quality improvement eliminates rattling noises from tolerance variations without interfering with the normal operation or disengagement of the locking mechanism.
3Reliability
If the tailgate is pre-stressed in the direction of the seal when in the locking position, then the sealing effectiveness is improved, but a sudden discharge blow and abrupt movement occur when the locking pawl is released
Solution Approach 1:
The mechanism performs a preliminary action by moving the locking pawl tangentially while it remains engaged with the rotary latch. This initial movement relieves the pre-stress from the seal before the locking pawl is fully disengaged, preventing sudden discharge blow and abrupt tailgate movement when opening.
4Reliability
If a powerful motor is used to overcome the spring force and pre-stress, then the opening function is reliable, but the device complexity and cost increase
Solution Approach 1:
The opening movement is segmented into two distinct phases: tangential movement while engaged with the rotary latch (relieving pre-stress gradually), followed by radial outward movement to disengage. This segmentation allows a smaller, less powerful motor to perform the function reliably by breaking down the total work into manageable stages rather than requiring one large motor to overcome all forces simultaneously.
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 mechanism reduces noise and pre-stress-related issues while enabling a compact, cost-effective design with lower power requirements, enhancing comfort and functionality.
Implementation Method 1
a locking pawl (7), which is spring-loaded and pre-stressed in the direction of the locking position
Implementation Method 2
The movement of the locking pawl from the engagement position to the opening position takes place in opposition to the force exercised by a spring element
Implementation Method 3
a rotary latch (4) which surrounds a locking element (2) in a locking position of the locking element (2)
Implementation Method 4
a drive element (11), which serves to couple a coupling section (18) of the locking pawl (7) and which moves the locking pawl (7) between the engagement position and a release position (7')
Data Source
AI summary
A motor vehicle door lock includes a rotary latch which in a locking position encompasses a locking element that is pre-tensioned in a direction of an open position releasing the locking element. A pawl is in engagement with the rotary latch such that the latch is inhibited from moving towards the open position. A coupling section of the pawl is coupled to a drive element which moves the pawl between an engagement position and a release position, the release position allowing the rotary latch to move toward the open position. A force is applied to the pawl only in the engagement position thereof and the force application holds the pawl in engagement with the rotary latch.