Coaxial Connector with Nested Sleeve for EMI Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing millimeter wave and microwave connectors suffer from unprotected spring fingers that are prone to damage and electromagnetic interference (EMI) leakage, which affects their performance and reliability, especially in high-frequency applications.
Innovation Solution
The design incorporates a solid outer sleeve that encloses the jack's outer contact spring fingers, ensuring they are protected and minimizing EMI leakage, with a 3-stage sequential alignment for proper contact engagement and the use of air as the primary dielectric to reduce impedance matching issues, along with a preloaded internal spring for maintaining a butt-mated condition and a robust center contact retention system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If spring fingers are exposed for contact engagement, then ease of operation is improved, but reliability deteriorates due to damage susceptibility and EMI leakage
Solution Approach 1:
The alignment hood is nested within the outer sleeve structure, creating a protective enclosure for the spring fingers. The outer sleeve acts as an outer shell that contains the alignment hood and spring fingers, similar to nested dolls, providing protection while maintaining functional access.
Solution Approach 2:
The alignment hood serves as an intermediary structure between the exposed spring fingers and the external environment. It mediates the interaction by providing a protective barrier that allows contact engagement while preventing direct exposure to damaging factors and EMI.
2Device complexity
If alignment hood is used as outer contact, then device complexity is reduced, but harmful factors increase due to EMI leakage
Solution Approach 1:
The alignment hood is nested within the outer sleeve, creating a multi-layered protective structure. This nesting arrangement allows the alignment hood to maintain its simplified contact function while the outer sleeve provides the EMI shielding barrier, resolving the contradiction between simplicity and harmful factor reduction.
Solution Approach 2:
The connector is segmented into distinct functional zones: the alignment hood for contact engagement and the outer sleeve for EMI protection. This segmentation allows each component to specialize in its primary function without compromising the other, reducing overall harmful factors while maintaining operational simplicity.
3Reliability
If outer diameter is increased for EMI protection, then reliability is improved, but volume increases
Solution Approach 1:
The nested structure of the alignment hood within the outer sleeve allows EMI protection to be achieved without significant volume increase. The components share the same spatial envelope, with the outer sleeve utilizing the existing outer diameter of the connector assembly rather than adding external bulk.
Solution Approach 2:
The EMI protection is achieved by utilizing the axial dimension and internal space of the existing connector structure rather than increasing the radial outer diameter. The outer sleeve extends along the axial direction and utilizes the internal volume already present in the connector design.
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 configuration enhances the connectors' durability and performance across a wide temperature range, maintains low voltage standing wave ratio (VSWR), reduces signal loss, and improves system-level reliability by allowing for more data transmission through smaller connectors, while also enabling field-replaceable components for reduced service time.
Implementation Method 1
The jack has an internal spring that compensates for tolerance stack-up and ensures that all coaxes in any multi-contact and multi-connector arrangement are butt-mated when the host connectors are fully mated
Implementation Method 2
Air is the predominant dielectric over the length of the connector assembly, which allows for a small inner diameter (ID) for the outer contact and large outer diameter (OD) for the center contact. Using air as the primary dielectric also reduces or eliminates impedance matching variables in the assembly due to the reduction of material property and dimensional variations inherent with any solid dielectric material.
Data Source
AI summary
A subminiature coaxial connector including a matched impedance plug and jack for coupling printed circuit boards, RF modules, coaxial cables, and the like, and minimizing RF or microwave signal losses and/or degradations. The plug and jack each comprises a coaxial structure including an outer tubular conductor and a center contact held in place by a dielectric sleeve within the outer tubular conductor. The geometries of these elements are such that when the plug and jack are fully joined, the elements are coextensive and butt-mated, without steps, gaps, or other discontinuities. By combining structural functions into the electrical conductors, the present invention allows for fewer parts and shorter mating distances than is available in the prior art. Despite the small Size 20 connectors that are achievable with the present invention, low voltage standing wave ratios (VSWR's) can still be observed through 67 GHz, with theoretical cutoff frequencies in excess of 100 GHz.