1. Analysis of the status quo of China's military aviation connector standards
1.1 Overview of China's military aviation connector standards
According to the system, China's military aviation connector standards can be divided into two categories: Russian system standards and US military standard systems standards, and can be divided into three categories: national military standards, industry standards, and enterprise standards.
The so-called Russian system standard refers to the electric connector standard prepared by China in the process of imitation of Russian electric connector products.
Due to specific historical reasons, Russian system standards rarely appear in the form of national standard (GB), national military standard (GJB), navigation standard (HB), and electronic standard (SI), but each product has enterprise technical conditions.
In the 1980s and 1990s, China converted a large number of electrical connector standards in the US military standards. Prepared the US military standard system standard. In order to be in line with international standards, most standards have been converted using equivalent methods. According to incomplete statistics, as of the end of 2001, China's existing US military standard system electrical connector standard has 264 items, of which 49 are closely related to the aviation industry.
China's military aviation connector manufacturing enterprises are composed of four industry sectors: electronics industry, aerospace industry, aerospace industry and local military industry groups. In addition to local military groups, all industries have their own electrical connector standards, but the number is relatively small; relatively speaking, the national military electrical connector standard (GJB) is more than the industry standard; overall, most Standards appear in the form of enterprise standards, and even industry standards are specific detailed specifications of products. General specifications are generally stipulated by national military standards. In China, the standard of electrical connector products is mainly enterprise standards. Even if the national military standards have been issued, each enterprise still needs to prepare the technical conditions of its products when organizing production, which makes the number of enterprise standards large.
In addition, the so-called military aviation connector only refers to the connector used in the aviation field. As for the standard used for the electrical connector, most of it does not have specificity. The product standard adopted by the military aviation connector is derived from the national military standard. The standards used by ships, weapons, and electronics are basically the same. Therefore, the overview of China's military aviation connector standards basically reflects the overview of China's military electrical connector standards.
1.2 Analysis of the structure, performance and applicable scope of the current standard
For the analysis of the structure, performance and applicable scope of the current standard, see Table 1.
1.3 Various types of electrical connector standards and their application status
1.3.1 Standard for reading electrical connectors
The current development of circular electrical connector standards supporting aviation mainframe and airborne requirements can be divided into three stages:
a. The old models from the 50s to the 60s used the relevant standards of the Russian series of products.
b. China ’s own models developed in the 70s and 80s used in-service models developed by China have a relatively high level of relevant standards for medium-density series products.
c. Since the 1990s, the development of new models has mainly used the relevant national military standards of the US military standard series of products.
The above-mentioned electrical connector product standards present the technical level of three grades of low, medium and high, which reflects the evolution process and development trend of China's electrical connector standards. The current electrical product standards for circular electrical connectors are basically complete. They play an important role in the aviation military aircraft field and can basically meet current needs.
1.3.2 Standards for printed circuits and resistive electrical connectors
Printed circuit electrical connectors are used for internal signal transmission of airborne equipment and are used in large quantities. The rectangular electrical connector is mainly used for the connection between the equipment and the wire connection between the equipment inner panel and the board.
The highly reliable wire spring structure is the main structure of China's aviation printed circuit electrical connectors and some rectangular electrical connectors since the 1980s. Highly reliable wire spring structure electrical connector products represent the most advanced contact structure today.
There are 7 national military standards for printed circuits and rectangular electrical connectors with high reliability wire spring structure, including 1 general specification for printed circuit electrical connectors, 5 detailed specifications for printed circuit electrical connectors, and rectangular electrical connectors Standard I.
There are 5 aviation industry standards for highly reliable wire spring structure printed circuits and rectangular electrical connectors, including 3 for high reliability wire spring structure and 2 for open hole structure.
China ’s aircraft imported from Russia use a large number of printed circuit wire spring structure electrical connectors (1 ′ PTIM, rpm-IM series) and frame-type rectangular connectors (PIIKM series), accordingly, China also introduced A large number of Russian enterprise standards basically meet the demand for production.
The current printed circuit and rectangular electrical connector standards in China refer to the leaf spring structure standards (MIL-C-55302, DIN4112, etc.) in terms of structure, installation, contact arrangement, contact spacing, etc., which can be easily compared with international standards. Connect. At present, the printed circuit and rectangular connector standards can basically meet the development and production needs.
1.3.3 Standard for pumping connectors
This type of connector is not the main business of aerospace system connector manufacturers. Most coaxial connector products used in the aerospace industry are ordered from professional electronics system manufacturers, while military aviation connector manufacturers have a very limited variety of products. The orders placed by the airborne equipment factory are mainly for electronics and foreign businessmen. According to rough statistics, there are 7 MIL series standards related to coaxial connector products, and each standard includes hundreds of detailed specifications with detailed contents. There are more than 200 equivalent and equivalent industrial standards and national military standards in China, and they are basically complete. Among all types of connector products, the number of coaxial connector standards is the largest, which basically meets the requirements of aviation The demand of the machine factory.
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