Magnetic Coil Touch Module for Slim Haptic Feedback

Solution Overview

Problem

Conventional touchpads with elastic dome switches are bulky, increasing the thickness and volume of electronic devices, which is not suitable for modern slimness requirements.

Innovation Solution

A touch module using magnetic coils and a magnet, where the coils sense the magnetic field to generate vibrations, providing feedback to the user while being stacked in multiple layers for precise sensing and strong vibration generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If elastic dome switch button or elastic piece is used to generate vibration feedback, then vibration feedback is achieved, but the thickness and volume of the touchpad are increased

Engineering Contradiction:

Improvevibration feedbackVSAvoidthickness of touchpad

Core Design Contradiction:

ReliabilityVSLength of stationary object

Solution Approach 1:

The patent replaces the conventional mechanical elastic dome switch or elastic piece with a magnetic field-based vibration generation system. The magnetic coils generate magnetic fields that interact with the magnet to produce vibration feedback, eliminating the need for bulky mechanical components and reducing the touchpad thickness.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent transitions from a three-dimensional mechanical vibration structure (elastic dome/piece) to a two-dimensional planar magnetic coil arrangement. The magnetic coils are wound in multiple layers within the same plane, allowing vibration generation without increasing the vertical thickness of the touchpad.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Reliability

If elastic dome switch button or elastic piece is used to generate vibration feedback, then vibration feedback is achieved, but the volume of the touchpad is increased

Engineering Contradiction:

Improvevibration feedbackVSAvoidvolume of touchpad

Core Design Contradiction:

ReliabilityVSVolume of stationary object

Solution Approach 1:

The patent replaces the conventional mechanical elastic dome switch or elastic piece with a magnetic field-based vibration generation system. The magnetic coils generate magnetic fields that interact with the magnet to produce vibration feedback, eliminating the need for bulky mechanical components and reducing the touchpad thickness.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs a multi-layered winding structure where magnetic coils are wound in multiple layers (first, second, third, and fourth wiring layers) within the same spatial footprint. This nested arrangement increases the effective coil density and vibration strength without increasing the overall volume of the touchpad.

Inventive Principle:

Principle #7Nested doll (Nesting)

3Measurement precision

If magnetic coils are wound in multiple layers with identical winding directions, then sensing precision and vibration strength are improved, but device complexity is increased

Engineering Contradiction:

Improvemagnetic field sensing precisionVSAvoidcoil structure complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent transitions from a three-dimensional mechanical vibration structure (elastic dome/piece) to a two-dimensional planar magnetic coil arrangement. The magnetic coils are wound in multiple layers within the same plane, allowing vibration generation without increasing the vertical thickness of the touchpad.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent divides the magnetic coil system into multiple separate wiring layers (first, second, third, and fourth wiring layers), each containing sensing lines wound in the same direction. This segmentation allows for precise magnetic field sensing and strong vibration generation while maintaining a compact structure that can be manufactured using standard multi-layer PCB techniques.

Inventive Principle:

Principle #1Segmentation

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 touch module effectively reduces the thickness and volume of touchpads while maintaining vibration feedback, meeting the requirements for slim electronic devices by using a layered winding structure of magnetic coils to sense and generate vibrations.

Implementation Method 1

When the magnetic coils sense a magnetic property (e.g., a magnetic field) of the magnet, the magnetic coils generate a vibrating effect

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS11983377B2Touch module

Publication Date: 2024.05.14 PRIMAX ELECTRONICS LTD

AI summary

A touch module includes a base plate, a magnet, a touchpad and a magnetic board. The magnetic board includes a first sensing line, a second sensing line, a third sensing line, a first communication part and a second communication part. The touchpad is located over the base plate. The magnetic board is arranged between the touchpad and the magnet. The first sensing line, the second sensing line and the third sensing line of the magnetic board are in parallel with each other and stacked on each other. The first sensing line is electrically connected with the second sensing line through the first communication part. The second sensing line is electrically connected with the third sensing line through the second communication part. The first sensing line, the second sensing line and the third sensing line sense a magnetic field of the magnet and generates a vibration.