Spring-Loaded Fluid Connector Sealing With Low-Torque Threads

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing fluid connectors require high torque for sealing, which can lead to operator fatigue and galling of threads, and are prone to leakage due to vibration and pressure, especially in high-pressure applications.

Innovation Solution

A fluid connector design featuring a fitting with a counterbore, a spring, and a seal carrier that applies biasing force to maintain sealing without relying on high torque, using radial and face seals to prevent leakage, and incorporating parallel threads to reduce galling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If tapered threads are used to create a mechanical seal connection, then sealing capability is improved, but large torque is required leading to operator fatigue and galling

Engineering Contradiction:

Improvesealing capabilityVSAvoidtorque application difficulty

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The sealing function is segmented from the threading function. The connection is divided into two independent sealing mechanisms: thread sealing (preventive) and face seal sealing (primary). This allows the threaded connection to be loosened without compromising the primary sealing function, reducing the torque needed for assembly and disassembly operations.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A seal carrier with face seals acts as an intermediary element between the fitting and the port. This intermediary provides the primary sealing function, allowing the threaded connection to serve mainly for positioning and secondary sealing, thereby reducing the torque requirement while maintaining reliable sealing.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If large torque is applied to tighten tapered threads, then sealing is achieved, but galling occurs due to friction between threads

Engineering Contradiction:

Improveseal connectionVSAvoidthread galling

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The design accepts that some thread friction is inevitable but converts the harmful galling effect into a benefit by using parallel threads instead of tapered threads. Parallel threads reduce friction and galling while still providing adequate mechanical connection, and the face seal compensates for any minor leakage, effectively converting the potential harm of thread friction into a manageable design parameter.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Strength

If threaded connection is used to secure fitting, then connection strength is improved, but vibration and pressure cause rotation and loosening

Engineering Contradiction:

Improveconnection strengthVSAvoidconnection stability

Core Design Contradiction:

StrengthVSStability of the object's composition

Solution Approach 1:

The seal carrier is designed to be dynamic rather than fixed, allowing it to move axially in response to pressure changes and vibration. The spring-loaded seal carrier automatically adjusts its position to maintain sealing contact, providing dynamic adaptation to operating conditions while the threaded fitting provides stable mechanical anchoring.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The face seal maintains continuous sealing contact through the spring biasing force, ensuring that sealing is not interrupted by vibration or pressure fluctuations. The spring continuously pushes the seal carrier against the port face, maintaining uninterrupted sealing action throughout operation.

Inventive Principle:

Principle #20Continuity of useful action

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 design reduces the need for high torque during assembly, minimizes galling, and ensures effective sealing across various pressure levels, preventing fluid leakage and maintaining connection integrity even under vibration.

Implementation Method 1

a spring having a first end interfacing with the annular shoulder of the counterbore and a second end interfacing with a first end of the seal carrier, wherein the spring is configured to apply a biasing force on the seal carrier toward the internal surface of the port

Methodology Applied

Scientific EffectSpring: Spring

Data Source

PatentUS11549621B2Fluid connector

Publication Date: 2023.01.10 PARKER INTANGIBLES LLC

AI summary

An example fitting includes: a fitting body having counterbore, where the counterbore defines an annular shoulder within tire fitting body: a spring having a first end interfacing with the annular shoulder of the counterbore; and a seal carrier having: (i) a first end face interfacing with a second end of the spring, (ii) a second end face configured to interface with an internal surface of a port, such that the spring is configured to apply a biasing force on the seal carrier toward the internal surface of the port, (iii) a first annular groove on an exterior peripheral surface of the seal carrier, where the first annular groove is configured to have a radial seal disposed therein, and (iv) a second annular groove in the second end face, where the second annular groove is configured to have a face seal disposed therein.