Conical Centering Pins for Crankcase Bearing Cap Alignment

Solution Overview

Problem

The existing assembly process for motor vehicle crankcases with one-piece bearing cap casings is complex and costly, requiring multiple drilling stages and precise alignment of pins to ensure correct reassembly without shifting, which leads to increased energy consumption by the oil pump due to potential offset between lower and upper bearings.

Innovation Solution

Drilling two diametrically opposite holes in each casing and inserting conical dowels to create an imprint for alignment, allowing for reduced hole drilling and easier reassembly, with conical pins protruding 1-1.5 mm to maintain element positioning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional drilling and reassembly process is used to ensure bearing alignment, then manufacturing precision is improved, but device complexity and manufacturing time increase

Engineering Contradiction:

Improvebearing alignment precisionVSAvoidassembly process complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The conical pins are inserted into the bearing cap housing before final assembly with the cylinder housing. These pins create preliminary alignment marks (imprints) on the cylinder housing that guide the reassembly process, eliminating the need for complex drilling and alignment procedures during final assembly.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The conical pins serve as intermediary elements that transfer the alignment information from the bearing cap housing to the cylinder housing. By creating imprints that act as alignment guides, these pins mediate between the two housing components during reassembly, simplifying the alignment process.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Manufacturing precision

If traditional drilling and reassembly process is used to ensure bearing alignment, then manufacturing precision is improved, but loss of time increases

Engineering Contradiction:

Improvebearing alignment precisionVSAvoidassembly time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The conical pins are inserted into the bearing cap housing before final assembly with the cylinder housing. These pins create preliminary alignment marks (imprints) on the cylinder housing that guide the reassembly process, eliminating the need for complex drilling and alignment procedures during final assembly.

Inventive Principle:

Principle #10Preliminary action

3Ease of manufacture

If conical pins are used to create alignment imprints, then ease of manufacture is improved, but manufacturing precision may be compromised

Engineering Contradiction:

Improveassembly process simplicityVSAvoidalignment accuracy

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The conical pins have a specific geometric parameter (cone angle) that is optimized to create imprints of appropriate size and shape for accurate alignment. The conical shape allows the pins to be easily inserted while creating precise alignment marks on the housing surfaces.

Inventive Principle:

Principle #35Parameter changes

4Adaptability or versatility

If bearing cap housing is disassembled for crankshaft insertion, then adaptability is improved, but loss of time increases

Engineering Contradiction:

Improvecrankshaft insertion capabilityVSAvoiddisassembly and reassembly time

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

The conical pins are inserted into the bearing cap housing before final assembly with the cylinder housing. These pins create preliminary alignment marks (imprints) on the cylinder housing that guide the reassembly process, eliminating the need for complex drilling and alignment procedures during final assembly.

Inventive Principle:

Principle #10Preliminary action

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

Simplifies the assembly process by reducing the number of holes needed and ensuring accurate alignment, maintaining engine casing elements with conical pins, thereby reducing manufacturing time and costs while maintaining proper bearing alignment.

Implementation Method 1

positioning and tightening of the bearing cap housing on the cylinder housing to create an imprint on a single positioning element of the assembly comprising the cylinder housing or the bearing cap housing

Methodology Applied

Scientific EffectMechanical pressure: Mechanical Force

Data Source

PatentEP3819508B1Conical centring pin

Publication Date: 2022.04.27 RENAULT SA

Figure 1~3
Figure 4~6
Figure 7~9

AI summary

The invention relates to a method of mounting a bearing cap housing (2) on a cylinder housing (3) comprising the following steps: - drilling 2 diametrically opposed holes (25) in the bearing cap housing and 2 diametrically opposed holes (25) in the cylinder housing, said holes (25) of the bearing cap housing and of the cylinder housing being arranged opposite each other, - drilling 2n-2 holes (25) in the bearing cap housing or the cylinder housing, n being the number of crankshaft bearings of the housing, - insertion of two centering pins (5) in two diametrically opposed holes (25) on the cap housing side, - insertion of conical pins (6) in the other holes (25) on the cap housing side, - positioning and tightening of the bearing cap housing on the cylinder housing to create an imprint on a single positioning element of the assembly comprising the cylinder housing (3) or the bearing cap housing (2).