The contact finger structure, as a special type of contact, is connected between the pin and the socket, creating multiple contact points through its structural transition to form electrical interconnection. Each contact point acts as a bridge to balance the flow of current. Due to its simple structure, small size, and low cost, it is suitable for mass production and widely used in medium and high voltage switches, busbar connectors, high current connectors, sealed electrodes, high voltage cable end fittings, fuse connectors, and mechanical and electronic applications.

Compared with the traditional wire spring hole, Fried Dough Twists pin and other electrical connection structures, the contact finger structure significantly increases the contact area, thus reducing the current density at the contact position, and doubling the current carrying capacity of electrical interconnection devices. The existing tactile finger structures include plum blossom tactile fingers, Z-shaped tactile fingers, strap tactile fingers, and spring tactile fingers.

Among them, plum blossom touch refers to extruded or stamped parts, with many assembly components and complex assembly; The strap contact finger has the advantages of no need to press the spring, simple structure, multiple contact points, and strong conductivity compared to the plum blossom contact finger. However, it requires strict material heat treatment process, high processing accuracy, and relatively high cost;

Spring contact finger is a new type of contact finger structure that allows for large tolerances and errors in the design of the contact surface, with constant contact stress, low wear, and long service life. Therefore, it is widely used in sliding point contact and dynamic static contact equipment in high-voltage and ultra-high voltage circuit breakers.

The main problem in current research is that the ability to conduct current for a long time still needs to be improved under the same external dimensions. The Joule heating generated by the contact resistance of the touch finger can cause the material at the contact point to soften or even melt. Moreover, excessive temperature rise can cause a decrease in the elasticity of the contact fingers, resulting in poor contact and affecting the reliability of electrical contact. At the same time, high temperatures can cause a decrease in the insulation performance of materials, and may even lead to electrical breakdown or circuit short circuits.

The method of increasing contact force and contact area can lead to an increase in insertion and extraction force, accelerate material wear, cause plastic deformation or even damage to the contact material, and reduce the number of insertion and extraction times. Therefore, it is necessary to consider optimizing the structure of the spring contact finger to ensure a larger contact area and reduce contact resistance.