Vehicle Seat Longitudinal Adjuster Backrest Unlocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing longitudinal adjusters for vehicle seats do not effectively distinguish between unlocking mechanisms triggered by folding the backrest forward and manual actuation, leading to premature locking issues when transitioning from an easy-entry position back to the use position, which complicates the manufacturing and assembly process.
Innovation Solution
A longitudinal adjuster with a memory device that stores the set longitudinal seat position and distinguishes between unlocking mechanisms, using a blocking element to prevent premature locking when the backrest is raised, and a gear mechanism to control the actuating arm for precise locking, allowing for modular implementation and reduced part complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the longitudinal adjuster uses a simple locking mechanism without distinction between unlocking triggers, then the device complexity is reduced, but the reliability of locking control deteriorates due to premature locking
Solution Approach 1:
The locking mechanism transitions from a static state to a dynamic state based on the backrest angle. When the backrest is folded forward beyond a threshold angle, the unlocking trigger is activated, allowing longitudinal movement. When the backrest returns to the upright position, the mechanism automatically locks again. This dynamic behavior ensures reliable locking control without requiring complex additional sensors or actuators.
Solution Approach 2:
The longitudinal adjuster uses the backrest folding action itself as the unlocking trigger. The mechanical connection between the backrest and the locking mechanism allows the backrest movement to automatically activate the unlocking function, eliminating the need for separate control systems. The system serves itself by using its own structural movement to control the locking state.
2Reliability
If the longitudinal adjuster distinguishes between different unlocking mechanisms, then the reliability of locking control is improved, but the device complexity increases
Solution Approach 1:
The backrest folding mechanism serves multiple functions: it provides the easy-entry function by allowing longitudinal seat movement, and it simultaneously acts as the unlocking trigger for the longitudinal adjuster. The same mechanical structure that enables the backrest to fold forward also triggers the unlocking of the seat rail locking mechanism, eliminating the need for separate control systems for different unlocking scenarios.
Solution Approach 2:
The patent merges the easy-entry function with the longitudinal adjustment function by using a single unlocking mechanism triggered by backrest folding. The locking mechanism integrates both the easy-entry unlocking capability and the longitudinal position adjustment capability into one system, reducing overall complexity while maintaining reliable control.
3Ease of operation
If the backrest is raised before the memory position is reached, then the ease of operation is improved, but the reliability of position memory deteriorates due to premature locking
Solution Approach 1:
The locking mechanism is designed to maintain the unlocked state for a predetermined period or distance after the backrest is raised, allowing the seat to reach the memory position before locking occurs. This preliminary unlocked state ensures that the seat can be properly positioned at the memory location without premature locking interfering with the operation.
Solution Approach 2:
The system provides a buffer period where the locking mechanism remains disengaged even after the backrest is raised, preventing premature locking. This cushioning effect ensures that there is sufficient time and space for the seat to reach the correct memory position before the locking action occurs, maintaining both ease of operation and position memory reliability.
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
This solution enables precise control over the unlocking mechanism, reducing the number of individually configured parts and simplifying the manufacturing process while ensuring proper locking and unlocking functionality, enhancing the easy-entry function and overall mechanical design of the vehicle seat.
Implementation Method 1
the adjustment position being provided in a range of adjustment of the component that can be changed, and the automatic locking of the component can be effected by means of a gear mechanism and a locking element, the gear mechanism transmitting the movement of the component from its setting position to its operating position back to the locking element by means of a variable transmission ratio
Implementation Method 2
a lock to prevent longitudinal displacement of the vehicle seat, with the vehicle seat being transferrable from the use position to an easy-entry position for simplified access to the rear seats if the locking of the longitudinal adjuster of the vehicle seat is activated by folding the backrest forward is unlocked
Implementation Method 3
The locking lever can be subjected to a spring force by means of a first spring element in relation to the actuating lever, counter to the tensile force of the first Bowden cable
Implementation Method 4
The backrest can also act on the actuating lever by means of a first Bowden cable connected to it. Here, the first Bowden cable can be connected to the locking lever
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to a longitudinal adjuster for a vehicle seat (1) comprising a seat part (5) and a backrest (3), having a first seat rail (2), which is fixed to the seat part, and a second seat rail (4), relative to which the first seat rail (2) can be moved in the longitudinal direction (x). The longitudinal adjuster additionally has a lock for preventing a longitudinal movement of the vehicle seat, the vehicle seat (1) being convertible from the use position into an easy entry position for easily accessing the rear seats when the lock of the longitudinal adjuster of the vehicle seat (1) is unlocked by folding the backrest (3) forwards. Furthermore, a memory device is provided which stores a set longitudinal seat position that is changed and restored by carrying out a longitudinal movement of the vehicle seat (1). The longitudinal adjuster is additionally designed to make a distinction as to whether the longitudinal adjuster is locked by folding the backrest (3) forwards or by a manual actuation using a handle (200) in order to activate or deactivate the memory device. The invention further relates to a vehicle seat (1) comprising a seat part (5) and a backrest (3), said vehicle seat (1) having a longitudinal adjuster according to the invention.