Professional Connector Manufacturer

Low-frequency non-sealed electrical connectors are widely used in military electronic equipment, and their reliability directly affects the normal operation of equipment. When the ambient air humidity is close to saturation, or because of the heat transfer between metal and low temperature objects in the environment, the metal surface is prone to condensation, which leads to the decrease of insulation of electrical connectors. Nitrides and sulfides in the atmosphere combine with water vapor to form salt solution to form electrolytic corrosion on metal surface. When the density of the coatings on the metal surface is not high and there are porous spaces, the micro-battery can be provided for the electrolytic corrosion of salt solution. The larger the potential difference between the gold coatings and the intermediate coatings, the more serious the electrolytic corrosion is. The working environment of military electronic equipment is complex and changeable. The sealing level of low-frequency non-sealed electrical connectors is not high. High temperature, humidity and heat, salt mist and other adverse factors lead to frequent failure of electrical connectors.

At present, some electrical connectors adopt sealed structure design, which improves the reliability of electrical connectors in humid environment. For equipment, the sealing upgrade and replacement of electrical connectors involves a wide range of difficult work. In order to explore the sealing protection technology of non-sealed electrical connectors, this paper takes the low-frequency circular electrical connectors as an example, studies the sealing technology of the tail and the insertion surface of the electrical connectors, verifies the sealing effect through environmental test and electrical insulation performance test, and puts forward the sealing protection of electrical connectors for different working conditions. Recommendation.

The contact of humidity and salt mist with the inner conductor of electrical connector is the main cause of failure of electrical connector. The typical structure of low-frequency non-sealed electrical connector is shown in Fig. 1. By analyzing the structure, it can be seen that the external water vapor and salt mist enter the shell mainly through the tail of the connector and the insertion surface, and adhere to the inner conductor surface. The gap at the tail of the electrical connector is large, and the conductor and cable core of the electrical connector are almost exposed in the external environment. The gap at the interface of the electrical connector is not obvious. Once the moisture enters, it is easy to accumulate and not easy to dissipate, which causes long-term damage to the electrical connector.

At present, the sealing protection of low-frequency non-sealed electrical connectors is mainly based on the tail filling of two-component glue exempt agent. Different glue must be dispensed according to the proportion. It is difficult to operate in the field, and the tail filling glue can not solve the sealing problem of the jointing surface. Moisture and salt mist still exist through the jointing surface into the electrical connector shell path. The sealing technology used in this paper is divided into two aspects: tail seal and plug face seal. The tail seal adopts two kinds of glue filling technology, one component and two components, to cope with different working environments. The plug face seal adopts tape wrapping technology to improve productivity and operability under the condition of ensuring the sealing effect.