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Mono and Stereo Connector with Captured Nut
Two versions of a custom connector that ISL manufactured for a customer who needed both a Stereo and Mono type 3.5mm plug to mold onto his cable assembly.
Overview
A customer was building a hand-held Pulse Oxygen meter. He needed a 3.5mm plug to mold onto his cable assembly for the meter.
Challenge
The jack on the meter had a threaded bushing and the customer wanted a plug with a captured nut so that the plug and cable assembly could be attached securely to the meter.
Solution
ISL Products designed and manufactured both the stereo and mono plugs with a captured nut made to mate with the customer’s jack and thread to the customer’s device. The plug has a strain relief to secure the wire to the plug after soldering. It also has a Teflon inner sleeve to insulate the center pin of the plug’s tip from the sleeve. The Teflon was used to withstand the high heat of the soldering process and the heat from the over-molding process. A more commonly used material like PVC or PE would melt and cause the plug to malfunction.
Conclusion
ISL designed and manufactured both mono and stereo 3.5mm plugs with a captured nut that threaded securely onto the customer's pulse oxygen meter jack. Adding a strain relief protected the soldered wire connection, while a Teflon inner sleeve insulated the center pin and withstood the high heat generated during soldering and over molding, a task that more common materials like PVC or PE could not handle. This combination of features gave the customer a secure, reliable cable assembly connection built specifically for his medical device. This project shows how ISL can tailor connector design and material selection to solve the exact mechanical and thermal challenges of a customer's application.