Multi-lobed Pinch Sensor with Wide Activation Angle
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Solution Overview
Problem
Conventional pinch sensors for vehicular closure panels have a limited activation angle, typically around 35 degrees, which can fail to detect obstacles when the pinch force is applied obliquely, leading to potential damage.
Innovation Solution
A multi-lobed pinch sensor with resiliently deformable non-conductive tubular casing and equidistantly spaced electrically conductive conduits, allowing for a wide activation angle of at least 270 degrees by ensuring contact between conductive conduits and a reference element upon deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional contact pinch sensors with two wires separated by an air gap are used, then the sensor structure is simple, but the activation angle is limited to approximately 35 degrees per side, causing failure to detect oblique pinch forces
Solution Approach 1:
The sensor is segmented into multiple conductive elements (at least three conduits) arranged circumferentially within the casing, with each conduit capable of independently contacting the reference element. This segmentation allows the sensor to detect pinch forces from multiple directions simultaneously, expanding the activation angle from 35 degrees to at least 270 degrees while maintaining structural simplicity through modular arrangement
Solution Approach 2:
The invention transitions from a linear two-wire configuration to a multi-dimensional circumferential arrangement of conductive conduits around a central reference element. This dimensional change from 1D to 2D/3D spatial configuration enables detection across a wide angular range by distributing sensing capability throughout the circumferential space, allowing oblique forces from any direction to activate at least one conduit-reference element contact pair
2Adaptability or versatility
If the pinch force is applied obliquely to conventional pinch sensors, then the force direction varies, but the sensor fails to detect the obstacle due to limited activation angle
Solution Approach 1:
The circumferential distribution of multiple conductive conduits creates segmented sensing zones, each oriented to detect forces from specific angular directions. This segmentation ensures that oblique pinch forces, regardless of direction, will activate at least one conduit, maintaining reliable obstacle detection across the entire 270-degree activation angle range
Solution Approach 2:
The sensor employs more conductive elements than the minimum two-wire configuration, creating redundant detection pathways. This excessive action ensures that even when pinch forces are applied at oblique angles that might miss traditional sensor orientations, at least one conduit will contact the reference element, thereby maintaining detection 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
The solution provides a wide activation range, effectively detecting obstacles across various pinch directions, enhancing safety by preventing closure panel damage from oblique forces.
Implementation Method 1
a resiliently deformable non-conductive tubular casing
Implementation Method 2
When the two wires contact one another, the electrical resistance therebetween drops, and a controller connected to the two wires monitors the drop in resistance or voltage
Data Source
AI summary
In an aspect, a pinch sensor is provided, comprising: an elongate non-conductive casing enclosing first, second, and third elongate conductive electrodes; the first and second electrodes being separated by a portion of the casing, a capacitance between the first and second electrodes changing when an obstacle approaches the first electrode to provide a proximity indication of the obstacle to the pinch sensor; and, the second and third electrodes being separated by an air gap formed in the casing, a resistance between the second and third electrodes changing when the second and third electrodes come into contact upon compression of the casing by the obstacle to provide a contact indication of the obstacle with the pinch sensor.