Electrical Connector Solder Ball Retention via Hook Arms

The patent applies curvature by forming arc-shaped retaining arms instead of flat plates. The first and second retaining arms are bent into arc shapes with specific radii, creating a curved retaining space that better conforms to the spherical shape of solder balls. This curved structure provides better mechanical engagement and prevents solder ball displacement while maintaining structural simplicity.

The patent transitions from a two-dimensional flat plate structure to a three-dimensional arc-shaped structure. The retaining arms extend in multiple dimensions with specific curvature radii, creating a volumetric retaining space that provides enhanced mechanical constraint on the solder ball from multiple directions, improving retention reliability without significantly increasing complexity.

The patent applies asymmetry by making the second retaining arm inclined rather than vertical. The inclined arm creates an asymmetric force distribution during solder ball melting, allowing the molten solder to be pushed toward the first retaining arm. This asymmetric geometry breaks the surface tension barrier more effectively than a vertical configuration, enabling proper wetting and bonding.

The patent changes the geometric parameter of the second retaining arm from vertical to inclined, with the inclination angle being a critical parameter. This parameter change transforms the force vector during melting, enabling the molten solder to overcome surface tension and achieve proper adhesion to the substrate, thereby improving solder connection quality.