Cooled Piston Oil Guide Sleeve Grooves for Lower Friction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piston designs for internal combustion engines face challenges with high installation effort and frictional forces due to the use of spring-loaded cooling oil guide sleeves, which increase the complexity and wear of the cooling oil guide sleeve and connecting rod interface.
Innovation Solution
The introduction of circumferential grooves and oil pockets on the guide surface of the cooling oil guide sleeve and the support surface of the lower piston part allows for defined lubrication between the components, reducing friction and wear by eliminating the need for separate spring elements and enhancing the piston's functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If spring-loaded cooling oil guide sleeves are used to transfer cooling oil from the connecting rod to the piston, then the cooling oil transfer function is improved, but the installation effort and device complexity increase significantly
Solution Approach 1:
The patent removes the spring element from the cooling oil guide sleeve assembly, extracting the problematic component that caused high installation effort and complexity. The cooling oil guide sleeve is redesigned to function without the spring-loaded mechanism, simplifying the overall structure while maintaining the essential cooling oil transfer function from the connecting rod to the piston.
Solution Approach 2:
The patent introduces circumferential grooves that divide the cooling oil guide sleeve into multiple functional zones: an upper groove for receiving cooling oil, a lower groove for lubrication, and intermediate sections. This segmentation allows the single component to perform multiple functions (cooling oil transfer, lubrication, and sealing) without requiring additional spring elements or complex assembly procedures.
2Reliability
If spring elements are used in the cooling oil guide sleeve, then the cooling oil transfer reliability is improved, but frictional forces and wear increase
Solution Approach 1:
The patent introduces lubricating oil as an intermediary substance between the cooling oil guide sleeve and the connecting rod head. The lower circumferential groove receives lubricating oil from the connecting rod, which then lubricates the contact surfaces between the cooling oil guide sleeve and the connecting rod. This intermediary lubricating layer reduces direct metal-to-metal contact, minimizing friction and wear while maintaining reliable cooling oil transfer.
3Object-generated harmful factors
If circumferential grooves and oil pockets are introduced, then lubrication is improved and wear is reduced, but manufacturing complexity increases
Solution Approach 1:
The circumferential grooves are designed as continuous rings rather than complex three-dimensional features, allowing them to be manufactured using standard machining processes such as turning or grinding. The grooves are positioned at different heights and depths but follow simple circular paths, making them suitable for conventional manufacturing methods without requiring advanced additive manufacturing or complex tooling.
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 design reduces friction and wear between the cooling oil guide sleeve and the lower piston part, improving the overall functionality and ease of installation of the cooled piston, while maintaining a secure seal and efficient cooling oil flow.
Implementation Method 1
at least one recess, preferably at least two recesses, which extends in the radial direction and penetrates the cooling oil guide sleeve, is made in the cooling oil guide sleeve, via which lubricating oil can be fed to an area between the cooling oil guide sleeve and the lower piston part
Data Source
Figure 1~2
Figure 3~5
AI summary
Piston (12) of an internal combustion engine, comprising a piston crown (10), a piston lower (11) connected to the piston crown (10), a piston pin which is mounted in the piston lower (11) and serves to connect the piston to a connecting rod (13) of the internal combustion engine, a first cooling chamber (15) for cooling oil formed between the piston crown (10) and the piston lower (11) for cooling the piston, wherein the first cooling chamber (15) is connected via at least one transfer bore (17) to a second cooling chamber (16) formed between the piston crown (10) and a piston lower (11), a cooling oil guide sleeve (19) which serves to guide cooling oil guided through a bore (18) in the connecting rod (13) towards the first cooling chamber (15), wherein a guide surface (22) of the cooling oil guide sleeve (19) is connected to a support surface (23) of the piston lower part (11) adjoins,wherein at least one circumferential groove (28, 29) is provided in the guide surface (22) of the cooling oil guide sleeve (19) and/or in the support surface (23) of the piston lower part (11).