Vehicle Seat Adjustment Mechanism Phase Shift Direction Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing motor vehicle seat adjustment mechanisms fail to accurately determine and control the relative movement of slide sections, leading to incomplete signal representation of their displacement.

Innovation Solution

A device with first and second sensors mounted on a moving component, facing a plurality of protuberances spaced according to a specific degree of freedom, detecting phase shifts to determine the direction of displacement, and an electronic control unit analyzing these signals to determine the direction of movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a single sensor is used to detect relative movement of slide sections, then the device complexity is reduced, but the measurement precision of displacement direction and phase shift is insufficient

Engineering Contradiction:
Improvedisplacement direction detection precisionVSAvoidsensor arrangement complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The detection function is segmented into multiple sensors (first sensor and second sensor) positioned at different locations on the movable slide section. Each sensor detects signals from protuberances at different phases, enabling determination of both displacement magnitude and direction through phase shift comparison between the two sensor outputs.

Inventive Principle:
Principle #1Segmentation

2Manufacturing precision

If protuberances are regularly spaced on the stationary component, then the manufacturing precision is improved, but the ability to detect bidirectional movement with phase shift information is limited

Engineering Contradiction:
Improveprotuberance spacing uniformityVSAvoidbidirectional movement detection capability
Core Design Contradiction:
Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The solution adds a spatial dimension to the detection system by positioning two sensors at different longitudinal locations along the slide section. This creates a phase difference between sensor outputs that encodes directional information, transforming a unidirectional detection system into a bidirectional detection system while maintaining regular protuberance spacing for manufacturing simplicity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Measurement precision

If the inter-sensor distance is set to zero or integer multiple of pattern length, then the device complexity is reduced, but the measurement precision of displacement direction is lost

Engineering Contradiction:
Improvedisplacement direction determination accuracyVSAvoidsensor positioning complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The critical parameter is the inter-sensor distance, which must be set to a non-zero value that is not an integer multiple of the protuberance pattern length. This specific parameter range creates a measurable phase shift between sensor outputs during bidirectional movement, enabling direction detection while avoiding degenerate cases where phase shift information would be lost.

Inventive Principle:
Principle #35Parameter changes

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

Enables precise determination and control of the movement between slide sections, allowing for accurate direction detection and improved functionality in motor vehicle seat adjustment mechanisms.

Implementation Method 1

each sensor is formed by a Hall effect sensor suitable for detecting the presence or absence of teeth facing said sensor

Methodology Applied
Scientific EffectHall effect: Hall Effect

Data Source

PatentEP3456580B1Adjustment mechanism for a vehicle seat
Publication Date: 2021.12.15 FAURECIA SIEGES D AUTOMOBILE SA
  • EP3456580B1 patent drawingFigure 1
  • EP3456580B1 patent drawingFigure 2
  • EP3456580B1 patent drawingFigure 3

AI summary

The motor vehicle seat adjustment mechanism includes: a first and a second sensor (9) mounted on a first component (1) of the adjustment mechanism, protrusions (10) provided on the second component of the adjustment mechanism, the first and second sensors (9) are mounted opposite the protrusions (10), the sensors (9) are positioned so that there is a phase shift between the signals detected by the two sensors (9), an electronic control unit (8) determines a direction of movement of the components from the detected phase shift.