Cold Spray Nozzle Path for Engine Valve Seat Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The cold spray method for forming valve seat coats on multiple engine valves is inefficient due to the need to repeatedly stop and start the raw material powder injection, resulting in increased cycle time and excessive coat formation.
Innovation Solution
The nozzle movement paths are optimized to allow continuous injection of the raw material powder while moving between valve seat locations, preventing excessive coat formation on non-target areas and reducing cycle time by spraying between valve seats and other engine components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the cold spray apparatus stops and restarts powder injection for each valve seat, then the coating can be applied to multiple valve seats, but the cycle time increases due to waiting time between injections
Solution Approach 1:
The patent implements continuous powder injection throughout the entire coating process across all valve seats. The injection system maintains uninterrupted powder flow while the nozzle moves between valve seats, eliminating the need to stop and restart injection. This continuous action removes the waiting time required for spray stabilization, directly reducing the coating cycle time and improving productivity.
2Productivity
If the nozzle moves between multiple valve seats with continuous spraying, then the cycle time is reduced, but excessive coat formation occurs on non-target areas
Solution Approach 1:
The patent divides the continuous spraying process into discrete coating zones corresponding to each valve seat. The nozzle movement path is segmented to approach, coat, and retract from each individual valve seat in sequence. This segmentation allows continuous powder injection while ensuring material is deposited only on targeted valve seats, preventing excessive coating on non-target areas through controlled spatial delivery.
Solution Approach 2:
The patent applies coating material locally to specific valve seat areas through controlled nozzle positioning and movement. The continuous spray is spatially directed so that powder is delivered only to the intended valve seat surfaces during the approach and coating phases, while retracting movements minimize material deposition on non-target areas. This local quality control ensures precise material placement throughout the continuous coating process.
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 shortens the coating cycle time and prevents excessive coat formation on critical areas, enhancing the efficiency and effectiveness of the cold spray method for valve seat coating.
Implementation Method 1
spraying a raw material powder such as metal powder onto the seating portion of an engine valve using a cold spray method
Implementation Method 2
accelerating the aerosol through a nozzle... grains constituting the powder fragment and form said deposit upon impact with the substrate
Data Source
Figure 1
Figure 2
Figure 3
AI summary
When forming valve seat coats at opening portions (16a1 to 16a8) of intake ports (16) provided at a cylinder block mounting surface (12a) of a semimanufactured cylinder head (3), the nozzle of a cold spray apparatus moves along a nozzle movement path for air intake (Inpl) that is set between any two of the plurality of opening portions (16a1 to 16a8), while continuing to spray a raw material powder. When forming valve seat coats at opening portions (17a1 to 17a8) of exhaust ports (17), the nozzle moves along a nozzle movement path for air exhaust (Enpl) that is set between any two of the plurality of opening portions (17a1 to 17a8), while continuing to spray the raw material powder.