Capacitor encapsulation on flexible printed circuit boards (FPCs) is a process with extremely high requirements for precision and reliability. In-line dispensing solutions based on piezoelectric valves are indeed the mainstream and efficient choice for addressing this challenge.
This solution primarily utilizes the non-contact dispensing technology of piezoelectric jet valves, combined with an in-line dispensing platform integrating a CCD vision system, to achieve high-speed, high-precision, and highly consistent encapsulation operations.
Ⅰ.Core Advantages: Piezoelectric Dispensing Valves
Compared to traditional dispensing methods, piezoelectric valves offer significant advantages in FPC capacitor encapsulation:
● High Precision and Minimal Adhesive Volume Control:Piezoelectric valves can achieve adhesive dot diameters as small as 0.2mm and adhesive volumes as low as 0.5 nanoliters (nL). This is crucial for encapsulating capacitors with extremely small pitches, precisely controlling the encapsulation range to prevent excessive adhesive overflow and pad contamination, or insufficient adhesive leading to inadequate protection.
● High Speed and High Efficiency:Piezoelectric valves can operate continuously at frequencies up to 1000Hz, far exceeding traditional pneumatic dispensing valves (approximately 200Hz). This means they can complete a large number of dispensing operations in a very short time, significantly increasing production capacity when used in online production lines.
● Excellent Consistency and Stability: Piezoelectric actuation precisely controls the displacement and speed of the dispensing pin, with adhesive volume consistency errors controlled within ±1%. This is critical for ensuring the uniformity of quality in large-volume FPC product production.
● Non-contact spraying:No Z-axis lifting contact is required, avoiding the risk of needle collision damaging the FPC or capacitor, and also solving the problem of dispensing height control caused by uneven FPC surface.
Automatic In-line PCB Glue Dispensing Machine SEC-DH400L
Second Intelligent In-line Glue Dispensing Machine SEC-DH400L adopts an integrated mineral casting design, with ultra-high precision and super stability, powerful expansion capabilities, and can realize ion cleaning, dispensing, detection, UV exposure and other functions;
Adopting a gantry structure, it can bear large loads, stable structure, and a powerful CCD visual positioning system, which can meet the requirements of Mark point positioning, edge positioning, and 3D scanning positioning; strong scalability, and can expand AOI detection 3D detection, UV exposure curing and other functions;
Strong platform compatibility, contact and non-contact dispensing, single-head and multi-head synchronous dispensing, automatic compensation and adjustment of double-head spacing, five-axis dispensing function based on needle A/R displacement, etc.
Ⅱ.System Integration: The Key to Online Dispensing Solutions
For piezoelectric valves to achieve maximum efficiency, a sophisticated online platform is essential. This system typically includes the following key components:
● High-Precision Motion Platform: Usually employing a gantry structure, coupled with linear motors and linear scales, it ensures high-speed and precise movement of the dispensing head on the FPC board, with a repeatability accuracy of ±0.01mm.
● CCD Vision Positioning System:This is the core of online automation. The vision system automatically identifies target areas on the FPC, accurately guiding the dispensing head for compensation and positioning even with slight deviations in the incoming material position.
● Fluid and System Control: Equipped with a sophisticated dispensing controller and adhesive temperature control system, it ensures stable adhesive viscosity, thereby guaranteeing consistent spraying over the long term. Some systems can also interface with MES (Manufacturing Execution System) for production data traceability.
The online dispensing solution based on piezoelectric valves is not a single action, but a systematic process that deeply integrates precision hardware, intelligent control, and rigorous process parameters. The complete process can be broken down into the following six core stages:
Piezoelectric Jet Valve F-P102
III. Applicability and Value
This solution has been widely applied in 3C electronics, semiconductor packaging, and other fields, specifically targeting the process requirements of FPC component reinforcement and lead encapsulation. In practical applications, some manufacturers have already replaced their original pneumatic jet valves with piezoelectric jet valves, successfully implementing them in FPC production lines and significantly improving dispensing efficiency and accuracy.
It should be noted that while the piezoelectric valve solution offers excellent performance, its equipment cost is relatively high. If the capacitor size is large, the encapsulation accuracy requirements are not high, or the production capacity demand is not large, the lower-cost screw valve or pneumatic jet valve solution can also be considered.
When evaluating a solution, the core is to clearly define your capacitor size, encapsulation adhesive characteristics (such as viscosity, whether it contains fillers), and production capacity requirements. This will allow you to select the most suitable piezoelectric valve model and platform configuration.
Second Intelligent has played an important role in theresearch, development, manufacturing, pre-sales and after-sales services of fluid dispensing robot, potting and coating solutions which range from various types of automatic fluid dispensing, potting, two-component potting machines and coating machines with desktop, free-standing, inline or cobot combined systems, and widely used in global electrical, electronics, home appliances, automobile, telecom, pharmaceutical, automotive electronics, semiconductor, aerospace, LED and more.
