Conduit Fitting Internal Grounding via Conductive Sleeve
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electrical conduit fittings lack effective internal grounding solutions, making them susceptible to environmental hazards and failing to provide continuous conductivity for equipment grounding, especially when exposed to external conditions.
Innovation Solution
The development of expansion and deflection conduit fittings with integrated ground transfer portions and conductive sleeves that ensure internal grounding by maintaining continuous contact with the conduit body, even during expansion and contraction, and allowing for angular movement to accommodate vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If external grounding is used with grounding screws, then grounding connection is established, but the ground connection is exposed to environmental hazards and susceptible to damage
Solution Approach 1:
The grounding system is nested within the conduit fitting structure itself. The internal cylinder with ground transfer portion is positioned inside the conduit body, and the conductive sleeve is nested within the conduit. This internal nesting protects the grounding connection from external environmental hazards while maintaining electrical continuity.
Solution Approach 2:
The ground transfer portion acts as an intermediary element that transfers the ground connection from the external environment into the protected internal space of the conduit. The conductive sleeve serves as another intermediary that maintains continuous electrical contact between the conduit and grounding system while allowing for movement and expansion.
2Reliability
If metallic conduits are used as equipment grounding conductors, then continuous conductivity is provided, but the required conductivity and continuity may be compromised without proper internal grounding
Solution Approach 1:
The conductive sleeve and ground transfer portion are designed to maintain continuous electrical contact throughout the conduit system. The sleeve extends along the conduit length and maintains constant electrical connection, ensuring uninterrupted ground path even during expansion, contraction, or vibration-induced movement.
Solution Approach 2:
The grounding system accommodates parameter changes in the conduit such as thermal expansion and contraction, vibration-induced movement, and angular deflection. The flexible conductive sleeve and slideable internal cylinder allow the grounding connection to adapt to these changing physical parameters while maintaining electrical continuity.
3Adaptability or versatility
If expansion fittings are used to accommodate longitudinal movement, then flexibility is provided, but grounding continuity may be compromised during expansion and contraction
Solution Approach 1:
The grounding system incorporates dynamic elements that move with the conduit. The internal cylinder is slideable within the conduit body, and the conductive sleeve can expand and contract with the conduit. This dynamic design maintains grounding continuity while accommodating longitudinal expansion and contraction movements.
4Adaptability or versatility
If deflection fittings are used to allow lateral movement and absorb vibrations, then flexibility is provided, but maintaining grounding contact during angular movement is difficult
Solution Approach 1:
The conductive sleeve functions as a flexible element that can bend and deform to accommodate lateral deflection and angular movement of the conduit. This flexible grounding path maintains electrical contact even when the conduit undergoes vibration-induced movement or angular deflection, ensuring continuous grounding reliability.
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
These fittings provide reliable internal grounding, preventing arcing and ensuring continuous conductivity, thus protecting electrical circuits from environmental damage and ensuring safe operation by maintaining a stable ground connection.
Implementation Method 1
The conductive sleeve has a central bore, and the first conduit connector is situated within the central bore such that a portion of the sleeve folds inwardly and is in contact with the outer surface of the first conduit connector
Implementation Method 2
Conventional expansion fittings accommodate longitudinal movement due to expansion and contraction of an electrical conduit—for example, due to fluctuations in temperature
Implementation Method 3
Deflection fittings are flexible fittings that allow one or more conduits to move laterally relative to one another, and allow the fitting to absorb some vibrations
Data Source
AI summary
Embodiments of the present invention are directed to conduit fittings with internal grounding capability. One expansion fitting allows for lengthwise expansion of an inner conduit utilizing an interior cylinder. The interior cylinder has a grounding portion that is conductive, and the grounding portion is electrically connected with a ground screw, Earth ground, or neutral ground. Another deflection fitting allows for angular deflection of connected conduits. The angular deflection fitting has an outer sleeve that is folded over an inner tube, and the outer sleeve is electrically connected with a ground screw, Earth ground, or neutral ground. Another expansion-deflection fitting shares the properties of the expansion fitting and the deflection fitting.