Rail Vehicle Suspension Rubber Spring Deflection Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current rail vehicle suspension systems fail to accurately detect the deflection of the rubber spring, which is crucial for load determination and level control, especially when the main air spring fails, leading to inadequate load monitoring and potential instability.

Innovation Solution

Incorporating a field sensor capable of capacitive or inductive detection of the rubber spring deflection, allowing for precise measurement of the spring's deformation and thereby inferring the forces acting on the suspension system, even when the air spring bellows are defective, ensuring reliable and maintenance-free operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If ultrasonic sensors are used to detect air spring bellows compression for level control, then level control and load determination are enabled, but the rubber spring deflection remains undetected leading to inaccurate load monitoring when air spring fails

Engineering Contradiction:
Improvelevel control accuracyVSAvoidload monitoring reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent replaces mechanical contact-based sensors with a field sensor (capacitive or inductive) that detects rubber spring deflection through electromagnetic fields. This non-contact measurement method provides reliable detection even when the air spring fails, as the field sensor directly measures the rubber spring's position without being affected by air spring condition.

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

Solution Approach 2:

The field sensor acts as an intermediary measurement device that indirectly detects the force acting on the suspension system by measuring rubber spring deflection. This intermediary measurement provides accurate load information even when the primary air spring support fails, ensuring continuous reliable monitoring.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If the air spring bellows and rubber spring are coupled in series, then emergency suspension is provided when main spring fails, but the undetected rubber spring stress compromises safety

Engineering Contradiction:
Improveemergency suspension capabilityVSAvoidundetected stress leading to potential failure
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The field sensor provides continuous feedback on the rubber spring's deflection and stress state. This feedback enables monitoring of the emergency spring's condition, allowing the system to detect when the rubber spring is bearing full load or experiencing excessive stress, thereby preventing failure through timely detection and response.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The rubber spring serves dual purposes: it provides emergency suspension support when the air spring fails, and simultaneously acts as a measurement target for the field sensor to monitor its own stress state. This self-monitoring capability ensures safety while maintaining the emergency support function.

Inventive Principle:
Principle #25Self-service

3Device complexity

If no sensor detects rubber spring deflection, then the system is simpler, but load determination is inaccurate especially during air spring failure

Engineering Contradiction:
Improvesensor system complexityVSAvoidload determination accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent employs a non-contact field sensor (capacitive or inductive) that measures rubber spring deflection through electromagnetic fields rather than mechanical contact. This approach achieves accurate load determination without complex mechanical linkages or contact-based sensor systems, maintaining relative simplicity while dramatically improving measurement accuracy during air spring failure.

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

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 field sensor provides accurate and robust detection of the rubber spring deflection, enabling effective load monitoring and level control independently of the air spring's state, ensuring reliable operation and cost-effectiveness.

Implementation Method 1

a field sensor (24) at least indirectly coupled to the rubber spring (14) and designed for capacitive or inductive detection of the spring travel of the rubber spring (14)

Methodology Applied
Scientific EffectCapacitive detection: Capacitance

Implementation Method 2

a field sensor (24) at least indirectly coupled to the rubber spring (14) and designed for capacitive or inductive detection of the spring travel of the rubber spring (14)

Methodology Applied
Scientific EffectInductive detection: Electromagnetic Induction

Data Source

PatentEP3541642B1Rail vehicle suspension and spring system for a rail vehicle
Publication Date: 2021.03.31 CONTITECH LUFTEDERSYSTEME GMBH
  • EP3541642B1 patent drawingFigure 1
  • EP3541642B1 patent drawingFigure 2
  • EP3541642B1 patent drawingFigure 3

AI summary

The invention relates to a rail vehicle suspension (2), arranged between a body (4) of a rail vehicle (6) and an undercarriage (8) of a rail vehicle (6), wherein the rail vehicle suspension (2) has a fastening plate (10), a pneumatic spring bellows (12), a rubber spring (14), a rim (18) provided on the upper part (16) of the rubber spring (14), and a connection part (22) provided on the lower part (18) of the rubber spring (14), wherein the pneumatic spring bellows (12) is fastened on the body side to the body (4) by means of the fastening plate (10), wherein the pneumatic spring bellows (12) is fastened on the undercarriage side to the rubber spring (14) by means of the rim (18), and therefore the pneumatic spring bellows (12) and the rubber spring (14) are coupled in series, and wherein the rubber spring (14) is fastened on the undercarriage side at least indirectly to the undercarriage (8) by means of the connection part (22), and wherein a field sensor (24) is provided which is at least indirectly coupled to the rubber spring (14) and is designed for capacitively or inductively detecting a spring travel of the rubber spring (14). The invention further relates to a spring system with such a rail vehicle suspension (2).