2results about How to "Avoid underfill" patented technology

The application provides a circuit board and a manufacturing method thereof. A medium layer source, i.e., a resin source, is divided into multiple parts, i.e., a top medium layer above a buried device and an intermediate medium layer between core boards. In a pressing process, the top medium layer above the buried device fills a gap between an upper frame (a second core board) and the buried device, and the intermediate medium layer between the core boards quickly fills a gap between a lower frame (a first core board) and the buried device. The vertical distance of resin flow is greatly reduced, the resin flowability is greatly improved, the problem of insufficient filling caused by insufficient resin flowability or mismatched curing speed can be effectively avoided, the problem of insufficient glue filling capacity of a traditional single-frame design when processing a large-thickness component is solved, and the reliability and stability of the buried device are improved.

This invention discloses an injection molding die for PVC pipe fittings, belonging to the field of injection molding technology. It includes: a fixed mold base with a first water-cooling plate fixed to one end face; a sliding mold base, parallel to one side of the fixed mold base; a fixed template, installed on the end face of the first water-cooling plate near the sliding mold base; a movable template, fixed to the side of the sliding mold base near the fixed template; two mold cavities, symmetrically arranged in the fixed template; and two core guide units, each installed in one of the mold cavities on the fixed template. In this invention, the fixed template and the movable template can fit tightly together to form two injection molding cavities for the PVC pipe fittings. The core shaft in the main shaft core device can be eccentrically or coaxially distributed with the mold cavity as the shaft rotates, which facilitates rapid filling of the mold with PVC material, shortens the injection cycle, prevents material shortages or incomplete filling due to flow obstruction, and improves product quality.