Inductive PCB Component Removal With Localized Adhesive Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rework on circuit board assemblies often requires localized and rapid heating to avoid damaging adjacent components, which is challenging due to heat transfer through radiation, convection, and conduction, making it difficult to efficiently remove adhesively attached components without causing damage.
Innovation Solution
A system using a complementary pair of high-permeability members with a central and peripheral pedestal, an inductive coil, and a coil driver to induce a magnetic field through the adhesively attached component, providing localized inductive heating and a return path for the magnetic field to reduce heat spread and facilitate component removal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional heating methods are used to remove adhesively-attached components, then the adhesive can be heated to facilitate removal, but heat spreads to adjacent regions through radiation, convection, and conduction causing damage to other components
Solution Approach 1:
The patent applies local quality by concentrating the magnetic field and heating effect precisely at the target component location using a shaped inductive coil and high-permeability member. The heating is localized to only the adhesively-attached component and its immediate adhesive layer, while adjacent regions remain unaffected by the thermal process
Solution Approach 2:
The patent replaces conventional thermal conduction-based heating with inductive heating using electromagnetic fields. An inductive coil generates a time-varying magnetic field that induces eddy currents in the high-permeability member, which in turn generates heat locally at the target component through electromagnetic induction rather than through contact or radiation from an external heat source
2Speed
If rapid heating is used to minimize heat spread, then localized heating can be achieved, but it requires specialized equipment and precise control to implement effectively
Solution Approach 1:
The high-permeability member acts as a self-heating element through electromagnetic induction. When placed within the inductive coil's magnetic field, the member automatically generates heat through induced eddy currents without requiring external heating elements, complex temperature control systems, or precise positioning mechanisms. The system leverages the inherent electromagnetic properties of the material to achieve rapid heating
Solution Approach 2:
The high-permeability member serves as an intermediary between the inductive coil and the adhesive layer. It concentrates and directs the electromagnetic energy to the target location, converting electromagnetic energy to thermal energy efficiently at the precise location where heating is needed, while the shaped coil provides the necessary magnetic field geometry
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 and efficient heating of adhesives attaching components to circuit boards, reducing adhesion and allowing for safe removal of components without damaging adjacent areas, thereby minimizing rework challenges in electronic assembly processes.
Implementation Method 1
The coil driver is configured to generate an AC current in the inductive coil circumscribing the central pedestal, thereby inducing the magnetic field therein
Implementation Method 2
A magnetic field is induced within the complementary pair of high permeability members... The magnetic field induced is directed through the adhesively-attached component
Data Source
AI summary
Apparatus and associated methods relate to removing an adhesively-attached component from a circuit board assembly. A complementary pair of high-permeability members are positioned on opposite sides of the circuit board assembly about the adhesively-attached component. Then, a magnetic field is induced within the complementary pair of high permeability members via a coil driver generating an AC current in an inductive coil circumscribing a central pedestal of the complementary pair of high-permeability members. The magnetic field induced is directed through the adhesively-attached component via a central pedestal located proximate the adhesively-attached component. A return path for the magnetic field is provided about a periphery of the adhesively-attached component via a peripheral pedestal.