E-bend Waveguide Circular Polarization Uniform Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional microwave treatment apparatuses face challenges in generating uniform electromagnetic field distribution, leading to inefficient heating due to disturbances and reduced radiation efficiency, particularly when using circularly polarized waves, which require longer waveguides and are prone to standing waves and reflected waves.
Innovation Solution
A compact microwave treatment apparatus with an E-bend waveguide structure and strategically placed openings on the heating chamber's lateral face, including a circularly-polarized-wave opening and a reflected-wave-suppression opening, to minimize disturbances and enhance the generation of circularly or elliptically polarized waves, ensuring uniform heating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional waveguide structure is used to generate circularly polarized waves, then the waveguide length must be increased, but this leads to increased device complexity and standing wave formation
Solution Approach 1:
The waveguide is divided into multiple sections with different cross-sectional dimensions. The first section has dimensions optimized for microwave propagation from the magnetron, while the second section has different dimensions optimized for generating circularly polarized waves at the heating chamber interface. This segmentation allows each section to perform its specific function efficiently without requiring excessive overall length.
Solution Approach 2:
The invention transitions from a single-dimensional waveguide to a multi-dimensional structure by varying the cross-sectional dimensions along the propagation direction. The waveguide cross-section changes from one set of dimensions in the first section to different dimensions in the second section, enabling mode transformation and circular polarization generation without extending the waveguide length excessively.
2Reliability
If the waveguide length is increased to generate circularly polarized waves, then polarization generation is improved, but standing waves and reflected waves increase
Solution Approach 1:
The waveguide structure employs dynamic variation in cross-sectional dimensions along the propagation direction. The transition from the first section to the second section with different dimensions creates a gradual impedance transformation, which reduces reflected waves and standing waves while enabling effective circularly polarized wave generation at the heating chamber interface.
3Volume of moving object
If a compact waveguide design is used, then device size is reduced, but circularly polarized wave generation efficiency decreases
Solution Approach 1:
Different sections of the waveguide are designed with locally optimized dimensions. The first section has dimensions optimized for compact propagation from the magnetron, while the second section has dimensions specifically optimized for circularly polarized wave generation at the heating chamber interface. This local optimization allows the compact overall design to maintain effective circularly polarized wave generation capability.
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 allows for efficient generation of circularly or elliptically polarized waves, reducing uneven heating and improving radiation efficiency, enabling more uniform heating of target objects while maintaining a compact design.
Implementation Method 1
a microwave treatment apparatus heats a target object (e.g. food) placed in a heating chamber with a microwave that is generated by a magnetron (i.e. a typical microwave generator) and then supplied to the heating chamber through a waveguide
Implementation Method 2
The multiple openings include at least one circularly-polarized-wave opening for generating a circularly polarized wave
Implementation Method 3
Conventional apparatuses face challenges in generating uniform electromagnetic field distribution, leading to inefficient heating due to disturbances and reduced radiation efficiency, particularly when using circularly polarized waves
Implementation Method 4
a microwave treatment apparatus heats a target object (e.g. food) placed in a heating chamber with a microwave that is generated by a magnetron
Implementation Method 5
a microwave treatment apparatus heats a target object (e.g. food) placed in a heating chamber with a microwave
Data Source
AI summary
A microwave oven includes a waveguide having an E-bend structure with multiple openings disposed on a lateral face of a heating chamber that allow the waveguide to communicate with the heating chamber. The waveguide has a first section for propagating a microwave from a magnetron toward the heating chamber, and a second section having a wide plane that abuts an outer wall of the heating chamber. The openings include at least one circularly-polarized-wave opening for generating a circularly polarized wave. A cross section of the first section orthogonally intersects a tube axis of the first section projects virtually along the tube axis of first section and onto a lateral face of the heating chamber, and the circularly-polarized-wave opening is configured such that its center is located outside the resultant projected region.