Utility Pole Shear-Off Coupling Assembly Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing shear-off coupling assemblies for utility poles are cumbersome, expensive, and prone to assembly errors due to numerous components, and they expose bolt connections to weather and abrasive conditions, which affects their reliability and safety, especially at low-velocity impacts.

Innovation Solution

A shear-off coupling assembly with recesses facing radially outward, allowing holding elements to release inwardly, reducing the number of components, shielding them from external influences, and eliminating the need for additional spacing or stabilization measures, while maintaining mechanical properties like bending and torsional stiffness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If bolt connections with external flanges are used, then the coupling assembly provides reliable shear-off behavior, but the flanges and bolt connections project from the pole causing damage or injury to the environment and are exposed to weather and abrasive conditions

Engineering Contradiction:
Improveshear-off reliabilityVSAvoidenvironmental exposure and safety hazards
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent inverts the conventional design by reversing the radial orientation of the flanges and recess openings. Instead of extending radially outward, the flanges now extend radially inward into the pole. This inversion protects the bolt connections from external weather and abrasive conditions while eliminating safety hazards to the environment. The release direction of the bolts is also reversed to radially outward, solving the collision problem through proper spacing and stabilization arrangements.

Inventive Principle:
Principle #13The other way round (Inversion)

2Reliability

If multiple bolt connections with flanges are used, then the coupling assembly provides reliable shear-off behavior, but the large number of components makes the assembly cumbersome and expensive and susceptible to assembly errors

Engineering Contradiction:
Improveshear-off reliabilityVSAvoidnumber of components
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges multiple separate components (flanges, bolt connections, washers, nuts) into an integrated coupling assembly design. The radially inward extending flanges with recesses and the radially outward releasing holding elements form a unified structure that reduces the number of discrete parts. This integration simplifies assembly, reduces manufacturing costs, and minimizes assembly errors while maintaining the shear-off reliability through the controlled frictional force between the integrated components.

Inventive Principle:
Principle #5Merging (Combining)

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 provides a reliable, easy-to-assemble, and cost-effective shear-off coupling assembly that performs well under various impact conditions without compromising the utility pole's mechanical properties, ensuring safety and compliance with European Standard EN12767.

Implementation Method 1

the impact forces only need to overcome frictional force between the various detachable components

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3081695B1Utility pole with shear off coupling assembly
Publication Date: 2019.05.29 NEDAL ALUMINUM BV
  • EP3081695B1 patent drawingFigure 1
  • EP3081695B1 patent drawingFigure 2a~2b
  • EP3081695B1 patent drawingFigure 3a~3b

AI summary

Utility pole, having a longitudinal direction and a radial direction, and comprising a base, a column and a coupling assembly for connecting the column to the base in a separable mamer. The coupling assembly comprises a recessed first end portion provided at an upper end of the base, a recessed second end portion provided at a lower end of the column, and a plurality of holding elements for coupling the first and second end portions to each other. Each holding element comprises a first formation, a second formation and a base part to interconnect said formations in the longitudinal direction. The first and second formation are arranged to fit in a recess of the first and second end portion respectively, and to be releasable therefrom in radial outward direction. The recesses of the first and second end portion are dimensioned and arranged to extend within a contour of the base and column, in radial direction.