Quadrupole Focus Coil Assembly for Stable Electron Beam Focusing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electron beam additive manufacturing systems face issues with stray magnetic fields and external interference, leading to manufacturing imperfections and increased system size due to the use of solenoid focus coil assemblies, which are prone to external magnetic field susceptibility and result in beam anomalies and displacements.
Innovation Solution
The implementation of a focus coil assembly utilizing quadrupole magnets with a yoke, which generates a dipole magnetic field and reduces stray fields, allowing for a more compact design and improved beam control by incorporating shielding and modular configurations to minimize external interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a solenoid focus coil assembly is used, then the electron beam can be focused, but stray magnetic fields are generated that cause beam anomalies and displacements
Solution Approach 1:
A magnetic shield (intermediary element) is introduced between the solenoid focus coil assembly and the electron beam path to block and contain the stray magnetic fields. The shield acts as a mediator that prevents the harmful magnetic field from reaching the electron beam, thereby eliminating beam anomalies and displacements while maintaining the focusing function of the solenoid coil.
Solution Approach 2:
The harmful stray magnetic field is extracted and isolated from the main system by using a magnetic shield that captures and contains the field within a specific region. This separates the useful magnetic field (for focusing) from the harmful stray field, allowing the latter to be managed independently without affecting beam precision.
2Manufacturing precision
If a solenoid focus coil assembly is used, then the electron beam can be focused, but the system size increases
Solution Approach 1:
The magnetic shield is nested within or around the solenoid focus coil assembly in a compact configuration. The shield is positioned to contain the magnetic field within the existing system boundaries, eliminating the need for additional space and allowing the focusing function to be maintained without increasing overall system volume.
3Manufacturing precision
If shielding is added to reduce stray fields, then beam control is improved, but device complexity increases
Solution Approach 1:
The magnetic shield is designed with uniform material properties and a homogeneous structure that matches the symmetry of the solenoid coil assembly. This homogeneous design simplifies the assembly process and reduces complexity by using uniform components rather than complex, non-uniform structures, while still effectively containing the stray magnetic fields.
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
This solution significantly reduces stray fields, decreases the system's size, enhances beam control, and increases the flexibility of electron beam manipulation, while reducing manufacturing complexity and costs by using quadrupole magnets to focus and steer the electron beam effectively.
Implementation Method 1
The quadrupole magnet includes first, second, third, and fourth poles and a yoke... configured to have a first magnetic polarity at their respective pole faces and a second magnetic polarity opposite the first magnetic polarity at their respective ends
Implementation Method 2
The electron beam is controlled by a focus coil assembly, which focuses the electron beam with a magnetic field such that the electron beam has a profile with a desired diameter and shape
Data Source
AI summary
A system for melting, sintering, or heat treating a material is provided. The system includes a cathode, an anode, and a focus coil assembly having a quadrupole magnet. The quadrupole magnet includes four poles and a yoke. The four poles are spaced apart and surround a beam cavity. Each of the four poles includes a pole face proximate the beam cavity and an end opposite the pole face. The first and third poles are aligned along an x-axis and configured to have a first magnetic polarity at their respective pole faces and a second magnetic polarity opposite the first magnetic polarity at their respective ends. The second and fourth poles are aligned along a y-axis and configured to have the second magnetic polarity at their respective pole faces and the first magnetic polarity at their respective ends. The yoke surrounds the poles and is coupled to the poles.