Surface-Mount LED Placement Using Corner Adhesive Against Reflow Tilt
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for mounting surface mount type LEDs on boards face challenges in accurately positioning the LEDs to prevent inclination caused by reflow, leading to potential deviations in illumination patterns, especially in applications like vehicle lights.
Innovation Solution
A method involving solder paste and adhesive coating, where the adhesive is discharged to the four corners of the LED's planned mounting positions to equalize the adhesive amount and prevent overlap with solder paste, combined with imaging and calculation to accurately position the LED's light emitting region, ensuring proper alignment and fixation during reflow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If adhesive is coated only at the center of LED mounting position, then the coating process is simple, but the LED inclines during reflow due to uneven adhesive distribution
Solution Approach 1:
The adhesive coating is divided into multiple discrete locations (four corners of the mounting position) rather than a single center point. This segmentation provides distributed support points that prevent LED inclination during reflow while maintaining a relatively simple coating process
Solution Approach 2:
Adhesive is applied at specific strategic locations (four corners) rather than uniformly across the entire mounting area. This localized approach provides precise mechanical support where needed to prevent inclination, while keeping the overall process simple
2Reliability
If adhesive amount is increased to prevent LED inclination, then LED positioning stability improves, but adhesive may overlap with solder paste causing defects
Solution Approach 1:
The adhesive support is segmented into four separate corner locations rather than one large continuous adhesive area. This segmentation allows sufficient adhesive quantity for stability while maintaining clear separation from solder paste regions, preventing overlap defects
Solution Approach 2:
The adhesive is positioned at the four corners of the mounting area, creating an asymmetric distribution pattern that provides stable support while naturally avoiding the central solder paste application area, thus preventing overlap
3Productivity
If LED mounting position is not precisely calculated based on light emitting region, then the mounting process is faster, but the illumination position accuracy deteriorates
Solution Approach 1:
The light emitting region position is calculated and determined before the actual mounting process. This preliminary positioning action ensures that subsequent mounting operations can proceed efficiently while maintaining high illumination position accuracy, as the target position is pre-determined
Solution Approach 2:
Manual or rough positioning methods are replaced with automated imaging and calculation systems that precisely determine the light emitting region position. This substitution of mechanical positioning with optical-detection-based positioning improves accuracy while maintaining productivity
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 effectively prevents LED inclination during reflow, ensuring precise mounting and maintaining the LED's intended illumination position, thereby improving the accuracy and reliability of surface mount type LED placement on boards.
Implementation Method 1
an adhesive coating step of coating an adhesive to the board so that an inclination of the surface mount type LED with respect to the board, the inclination of which being caused by reflow, is prevented when the surface mount type LED is mounted on the board
Implementation Method 2
a solder coating step of coating a solder paste to the board
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A component mounting method for mounting a surface mount type LED on a board, the method including: a solder coating step of coating a solder paste to the board; an adhesive coating step of coating an adhesive to the board so that an inclination of the surface mount type LED with respect to the board, the inclination of which being caused by reflow, is prevented when the surface mount type LED is mounted on the board; an imaging step of imaging, from above, the surface mount type LED before being mounted, to acquire imaging data; a calculating step of calculating a position of a light emitting region of the surface mount type LED based on the imaging data; a mounting step of mounting the surface mount type LED on the board via the solder paste and the adhesive based on the position of the light emitting region calculated by the calculating step; and a reflow step of applying the reflow to the board, on which the surface mount type LED is mounted.