Vehicle Seat Height Adjustment Assembly With Constant-Force Kinematics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle seat adjustment mechanisms experience varying adjusting forces and motor speeds during height adjustments, leading to non-uniform acoustics and potentially unpleasant user experiences.
Innovation Solution
A kinematic system is implemented using a linear element and transmission element that are adjustable relative to each other, maintaining a substantially constant adjusting force and motor speed by positioning the linear element at a right angle to the pivot points of swivel elements, allowing for uniform force introduction and favorable kinematics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a conventional linear adjustment device is used with pivotally coupled swivel elements, then the seat part assembly can be adjusted between different height positions, but the adjusting force varies along the adjustment path leading to non-uniform motor speed and acoustics
Solution Approach 1:
The patent changes the geometric parameter of the linear element's orientation relative to the pivot points. By positioning the linear element substantially perpendicular to the imaginary line extending through the front upper pivot point and the rear upper pivot point, the force transmission characteristics are optimized to provide uniform adjusting force throughout the adjustment path.
Solution Approach 2:
The patent introduces a dynamic adjustment mechanism where the linear element can change its position and orientation during the adjustment process. The linear element is movable along the adjustment path while maintaining its substantially perpendicular orientation to the pivot point line, allowing continuous adaptation to maintain uniform force application.
2Ease of operation
If the linear element is positioned to provide uniform adjusting force, then motor speed and acoustics are improved, but the device complexity increases due to precise positioning requirements
Solution Approach 1:
The linear element serves multiple functions simultaneously: it provides the adjusting force, maintains the optimized perpendicular orientation to the pivot point line, and moves along the adjustment path. This multi-functionality is achieved through the specific kinematic arrangement where the linear element's movement and orientation are coupled with the swivel elements' pivot points.
Solution Approach 2:
The linear element acts as an intermediary between the drive device and the seat part assembly. It translates the drive device's motion into uniform adjusting force on the seat part assembly while maintaining its specific geometric relationship with the pivot points, mediating the force transmission in a way that simplifies the overall system control.
Data Source
AI summary
An assembly of a vehicle seat comprises a seat part assembly, a floor assembly, a front swivel element that is pivotally coupled to the seat part assembly at a front, upper pivot point, and a rear swivel element that is pivotally coupled to the seat part assembly at a rear, upper pivot point. A drive device includes a linear element and a transmission element operatively connected to the linear element. In a first end position, the linear element takes a first angle to an imaginary line extending through the front, upper pivot point and the rear, upper pivot point, and in a second end position takes a second angle to the line, in an intermediate position the linear element is arranged at a right angle to the line and exceeds the right angle when adjusted between the first end position and the second end position.