One-Piece Common Rail Module for Leak-Resistant Assembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing common rail fuel injection systems require significant assembly time, are prone to leakage at high-pressure joints, and occupy substantial space due to individual components, complicating installation and maintenance.

Innovation Solution

A one-piece module for the common rail system is manufactured using additive manufacturing, integrating the common fuel line and injector bodies, with features like undulating shapes and internal channels to manage pressure and reduce leakage, and a combined connector for handling different fuel pressures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If multiple individual components (common rail, high pressure pipes, injectors) are assembled separately, then the system is easier to manufacture and assemble, but the assembly time increases and leakage risks at joints increase

Engineering Contradiction:
Improveease of manufactureVSAvoidassembly time
Core Design Contradiction:
Ease of manufactureVSLoss of time

Solution Approach 1:

The patent merges the common rail and high pressure pipes into a single integrated component manufactured by additive manufacturing. This eliminates the need for separate assembly of multiple high pressure joints, thereby reducing assembly time while maintaining ease of manufacture through advanced manufacturing processes

Inventive Principle:
Principle #5Merging (Combining)

2Adaptability or versatility

If multiple individual components are assembled separately, then each component can be optimized independently, but the number of high pressure joints increases leading to more leakage sources

Engineering Contradiction:
Improvedesign flexibilityVSAvoidleakage resistance
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

By integrating the common rail and high pressure pipes into one piece, the patent eliminates multiple high pressure joints that serve as potential leakage sources. The integrated design maintains design flexibility through additive manufacturing capabilities while significantly improving reliability by removing joint interfaces

Inventive Principle:
Principle #5Merging (Combining)

3Strength

If individual high pressure pipes with minimum bending radius and straight lengths are used, then the pipes can handle high pressure effectively, but the space required for the complete assembly increases

Engineering Contradiction:
Improvepressure handling capabilityVSAvoidspace claim
Core Design Contradiction:
StrengthVSVolume of stationary object

Solution Approach 1:

The integration of common rail and high pressure pipes into a single additive manufactured component allows for optimized space utilization. The design can incorporate necessary bends and routing within the integrated structure without requiring additional space for separate pipe installations, while maintaining pressure handling capability through appropriate wall thickness and material selection

Inventive Principle:
Principle #5Merging (Combining)

4Ease of manufacture

If multiple separate components are used, then the system can be manufactured using conventional processes, but the weight of the complete assembly increases due to more components and joining materials

Engineering Contradiction:
Improvemanufacturing process simplicityVSAvoidassembly weight
Core Design Contradiction:
Ease of manufactureVSWeight of stationary object

Solution Approach 1:

By consolidating multiple components into a single additive manufactured part, the patent eliminates the weight of joining materials (welds, bolts, seals) and reduces the total component count. While additive manufacturing is an advanced process, it enables this weight reduction while maintaining manufacturing feasibility

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

This approach reduces assembly time, minimizes leakage risks, and optimizes space usage, while enabling better thermal management and fuel control, resulting in a more compact and efficient fuel injection system.

Implementation Method 1

The one-piece module is made by additive manufacturing (also referred to as 3D printing)

Methodology Applied
Scientific EffectAdditive manufacturing: 3D Printing

Implementation Method 2

An advantage of the undulating shape is that the stiffness of the common fuel line from one injector body to the next in a longitudinal direction (x) of the common fuel line may be decreased, which in turn may decrease static stress when the one-piece module is mounted to an engine or engine component

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3721070B1A device for a common rail fuel injection system
Publication Date: 2025.10.08 VOLVO TRUCK CORP
  • EP3721070B1 patent drawingFigure 1
  • EP3721070B1 patent drawingFigure 2a~2b
  • EP3721070B1 patent drawingFigure 3~4

AI summary

The invention relates to a device (10) for a common rail fuel injection system (102), wherein the device (10) comprises a one-piece module (12) which comprises a common fuel line (14) and a plurality of injector bodies (16) in fluid communication with the common fuel line (14). The present invention also relates to a vehicle (100) comprising such a device (10). The present invention also relates to a method of manufacturing a device (10) for a common rail fuel injection system (102).