Cylinder Block Spray Deposit Compression for Oil Retention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increased pit area ratio on the surface of a cylinder block's spray deposit after honing processing leads to higher oil retention and increased oil consumption during engine operation due to gas pockets formed during the spraying process.
Innovation Solution
A producing method for a cylinder block that includes a spraying step to form a metallic deposit on the bore inner surface, a pressurizing step to compress and crush the gas pockets, and a honing step to finish the surface, reducing the pit area ratio and oil retention.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If spraying metallic material onto bore inner surface to form spray deposit, then surface coating is achieved, but gas pockets are formed creating pits that increase oil retention
Solution Approach 1:
The pressurizing step is performed before honing to pre-compress the spray deposit and eliminate gas pockets. This preliminary action prevents the formation of pits that would otherwise occur during subsequent honing, thereby reducing oil retention while maintaining surface coating quality
Solution Approach 2:
The gas pockets formed during spraying, which are initially harmful as they create oil-retaining pits, are converted into a compression target. By applying pressure in the pressurizing step, these gas pockets are eliminated and the spray deposit is densified, transforming the harmful porosity into a benefit by reducing future oil retention
2Ease of operation
If honing processing is applied to spray deposit surface, then sliding surface is finished, but pits from gas pockets remain increasing oil consumption
Solution Approach 1:
The pressurizing step is performed as a preliminary action before honing to remove gas pockets and densify the spray deposit. This ensures that when honing creates the sliding surface finish, the harmful pits are already eliminated, thereby achieving both good surface finish and reduced oil consumption
3Manufacturing precision
If additional boring processing is performed before honing to control bore inner diameter, then dimensional precision is improved, but manufacturing complexity increases
Solution Approach 1:
The pressurizing step combines two functions into one operation: it controls the bore inner diameter to the required dimensional precision while simultaneously eliminating gas pockets from the spray deposit. This merging of functions eliminates the need for separate boring and pressurizing steps, reducing manufacturing complexity while maintaining precision
Solution Approach 2:
The pressurizing step is designed to perform multiple functions: it densifies the spray deposit, eliminates gas pockets, controls bore inner diameter precision, and prepares the surface for honing. This multi-functionality reduces the total number of processing steps needed while achieving multiple quality objectives
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 method effectively reduces the pit area ratio and subsequent oil consumption by approximately 70% during engine operation by compressing gas pockets before honing, eliminating the need for additional boring processing.
Implementation Method 1
a pressurizing step of applying pressure to compress the spray deposit formed on the bore inner surface in the spraying step
Implementation Method 2
a spraying step of spraying a metallic material onto an bore inner surface of at least one cylinder bore formed in the cylinder block to form a spray deposit thereon
Implementation Method 3
a honing step of applying a honing processing to a surface of the spray deposit after the pressurizing step
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A producing method for a cylinder block (10) includes: a spraying step of spraying a metallic material onto a bore inner surface (11a) of at least one cylinder bore (11) formed in the cylinder block (10) to form a spray deposit (11b) thereon; a pressurizing step of applying a predetermined pressure onto a surface (11c) of the spray deposit (11b) formed on the bore inner surface (11a) in the spraying step; and a honing step of applying a honing processing to the surface (11c) of the spray deposit (11b) after the pressurizing step.