Protective Coating for Fracture-Split Connecting Rod Surfaces

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Fracture surfaces of components like connecting rods in internal combustion engines are sensitive and prone to damage, leading to strength deterioration and potential bearing damage from detached crack particles during assembly.

Innovation Solution

Applying a protective cover with a layer thickness of at least 1 μm and up to 20 μm to the fracture surfaces, which can be a coating or a separate protective element, to prevent damage and detachment of crack particles, ensuring the surfaces remain intact and functional.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If fracture surfaces are left exposed during assembly, then the assembly process is simpler and faster, but the fracture surfaces are damaged and crack particles detach causing bearing damage

Engineering Contradiction:
Improvestrength of assembled componentVSAvoidcomplexity of protective measure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The fracture surfaces are pre-coated with a protective substance (such as grease, oil, or special coating materials) before the assembly process begins. This preliminary protective action ensures that when the half-shells are assembled, the fracture surfaces are already protected against damage and crack particle detachment, eliminating the need for complex protective measures during assembly

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

A protective substance acts as an intermediary layer between the fracture surfaces and the assembly process. This intermediary coating (grease, oil, or special material) prevents direct contact and potential damage to the fracture surfaces, while also preventing crack particles from detaching and entering the bearing shells

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If a thick protective coating is applied to fracture surfaces, then protection against damage is improved, but the layer thickness exceeds the optimal range and may interfere with assembly

Engineering Contradiction:
Improveprotection of fracture surfaceVSAvoidlayer thickness control
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The protective coating is applied with controlled thickness parameters within the range of 1 μm to 20 μm. This parameter optimization ensures sufficient protection against fracture surface damage and crack particle detachment, while maintaining thin enough thickness to avoid interference with the assembly process and bearing shell clearance

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The protective coating is applied specifically to the fracture surfaces where protection is needed, rather than uniformly across the entire component. This localized application ensures optimal protection at the critical fracture areas while minimizing overall material addition and potential assembly interference

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3009701B1Fracture split component, in particular fracture split connecting rod or fracture split main bearing cover of a crankcase of an internal combustion engine
Publication Date: 2021.01.20 MAN TRUCK & BUS SE
  • EP3009701B1 patent drawingFigure 1
  • EP3009701B1 patent drawingFigure 2
  • EP3009701B1 patent drawingFigure 3

AI summary

The invention relates to a fracture-split component, in particular a fracture-split connecting rod or a fracture-split main bearing cap of a crankcase, the fracture-split component (1) having at least one defined fracture area (7) on which the component (1) forms associated fracture surfaces (19) is broken up and/or separated in such a way that the component (1) is divided into at least two partial elements (9, 11). According to the invention, at least one, preferably all, of the associated fracture surfaces (19) are provided with a protective cover (37; 39) at least in regions, in particular to prevent damage to the structure of the fracture surface and/or detachment of partial areas of the fracture surface (19). is.