Spark Plug Laser Welding BPP Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spark plug manufacturing methods using laser welding lack control over laser beam quality, leading to variations in exfoliation resistance of noble metal tips, which affects durability and ignitability.
Innovation Solution
A method employing a laser beam with a BPP value of 25 mm·mrad or less is used for laser welding, ensuring a deeper and narrower fusion area, enhancing exfoliation resistance by maintaining a smaller diameter throughout the focal point and preventing sputtered substance adhesion during the welding process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If laser welding is performed without controlling BPP value, then welding process is simple, but exfoliation resistance of noble metal tip varies and decreases
Solution Approach 1:
The patent applies parameter changes by controlling the BPP value of the laser beam within a specific range (15-25 mm·mrad) to optimize the welding process. This parameter control ensures consistent beam quality, which directly improves the exfoliation resistance of the noble metal tip while maintaining a relatively simple welding process without requiring complex additional equipment.
2Reliability
If laser beam diameter is large at focal point, then welding process is easier, but fusion area becomes shallow and wide reducing exfoliation resistance
Solution Approach 1:
The patent changes the beam quality parameter (BPP value) to achieve the desired fusion characteristics. By maintaining BPP within 15-25 mm·mrad, the laser beam produces a deeper and narrower fusion area, which significantly improves exfoliation resistance while maintaining manufacturability through standard welding procedures.
3Object-generated harmful factors
If BPP value is not controlled, then optical system is simpler, but sputtered substances adhere to optical components
Solution Approach 1:
The patent controls the BPP value parameter to minimize sputtered substance generation and adhesion to optical components. This parameter control prevents contamination of the optical system, maintaining system simplicity while eliminating the harmful effect of sputtered substance accumulation.
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 significantly enhances the exfoliation resistance of noble metal tips, maintaining ignitability while preventing sputtered substances from adhering to optical system components, thus improving the durability and performance of spark plugs.
Implementation Method 1
an electrode base member and a noble metal tip welded to the base member by means of a laser, or an electrode base member, a tip base member welded to the electrode base member and a noble metal tip welded to the tip base member by means of a laser
Implementation Method 2
laser welding process for subjecting the electrode base member and the noble metal tip to laser welding
Implementation Method 3
the noble metal tip is joined to the center electrode by way of a wedged, fused, solidified metal alloy
Data Source
AI summary
There is provided a method for manufacturing a spark plug capable of enhancing exfoliation resistance between an electrode base member or a tip base member and a noble metal tip or exfoliation resistance between a metal shell and an outer electrode. A method for manufacturing a spark plug 100 is a method for manufacturing the spark plug 100 having an electrode base member 121 and a noble metal tip 151 welded thereto by means of a laser or an electrode base member 131, a tip base member 171 joined thereto, and a noble metal tip 161 welded to the tip bases material by means of a laser, and the method includes a laser welding process of welding the electrode base member or the tip base member to the noble metal tip by means of a laser and through use of a laser beam whose BBP value assumes 25 mm·mrad (a radius · a half angle) or less at a time point when a laser beam PL1 enters a transfer optical system LM for guiding the laser beam to areas 128 and 158 to be welded where laser welding is to be performed.