Pantograph Bow With Permanent Magnets for Arc Deflection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing bows for capturing electrical current from catenary wires are damaged by electrical arcs formed due to frost, leading to structural degradation.

Innovation Solution

A bow design featuring a support bar with protective plates and permanent magnets that deflect electric arcs away from the support bar, using a magnetic field generated by the magnets to protect the support bar and associated components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the bow uses a conventional support bar structure to capture electric current by friction on the catenary wire, then the electrical power collection function is achieved, but the support bar is damaged by electric arcs during frost periods due to excessive heating

Engineering Contradiction:
Improvebow structure protectionVSAvoidelectric arc damage
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

A magnetic field is introduced as an intermediary between the electric arc and the support bar. The permanent magnet generates a magnetic field that deflects the electric arc away from the support bar, preventing direct contact and thermal damage while allowing the bow to continue collecting electrical power normally

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention converts the harmful electric arc into a beneficial deflected path. By using the magnetic field to redirect the arc, the harmful thermal energy is diverted away from the support bar, transforming the arc from a damaging factor into a controlled phenomenon that no longer threatens the structural integrity of the bow

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

2Reliability

If permanent magnets are added to deflect electric arcs away from the support bar, then the bow structure is protected from excessive heating, but the device complexity increases

Engineering Contradiction:
Improvesupport bar protectionVSAvoidbow structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention replaces potential mechanical protection systems (such as physical barriers or active cooling mechanisms) with a magnetic field-based solution. The permanent magnet creates a magnetic field that passively deflects electric arcs without requiring mechanical movement, complex control systems, or additional active components

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The permanent magnet provides self-service protection by continuously generating a magnetic field that automatically deflects electric arcs away from the support bar. The system requires no external power source, control mechanisms, or maintenance intervention - the magnet inherently performs the protective function through its magnetic properties

Inventive Principle:
Principle #25Self-service

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 effectively protects the support bar and associated components from electric arcs, ensuring durability and simplicity of implementation, including retrofitting existing systems.

Implementation Method 1

at least one permanent magnet fixed to the support bar and oriented so as to deflect an electric arc propagating from the catenary wire towards the support bar away from the latter

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Implementation Method 2

oriented so as to deflect an electric arc propagating from the catenary wire towards the support bar away from the latter

Methodology Applied
Scientific EffectLorentz force: Lorentz Force

Data Source

PatentEP3527418B1Bow for capturing an electric current comprising at least one permanent magnet
Publication Date: 2026.05.06 ALSTOM HOLDINGS SA
  • EP3527418B1 patent drawingFigure 1~2
  • EP3527418B1 patent drawingFigure 3

AI summary

Bow (18) for capturing an electric current by friction on a catenary wire (12) comprising a friction strip (22) mounted along a support bar (20) and at least one permanent magnet (24) fixed on the support bar (20) being oriented so as to deflect an electric arc (36) propagating from the catenary wire (12) towards the support bar (20) away from the latter.