PVC jacket material Yonglian 4.1m left turn camera wire
Development trend of automobile connector in new energy automobile industry
With China becoming the world's largest auto sales market, China's auto industry has also entered a new stage of development. It can be seen from the 12th Five year plan that in the next five years, China's automobile industry will shift from large-scale to strong strength in the past, and its development direction is mainly to promote energy-saving vehicles, including new energy vehicles.
According to the current draft plan, in 2015, China will promote the coordinated development of automobile industry and related industries, urban transportation infrastructure and environmental protection, shift from a large automobile manufacturing country to a powerful automobile country, and the annual sales volume is expected to reach 25 million vehicles in 2015. It will become the cornerstone of China's auto industry to become bigger and stronger. In 2015, the proportion of China's own brand automobile market will be further expanded. The domestic market share of independent brand passenger cars will exceed 50%, of which the domestic share of independent brand cars will exceed 40%. In addition, China's auto industry will shift from relying on the domestic demand market to going abroad on a large scale. In 2015, the export of independent brand cars accounted for more than 10% of production and sales.
In order to achieve this goal, the state will vigorously support energy-saving and environment-friendly vehicles with traditional fuels, new energy vehicles dominated by pure electric vehicles, and support the research and development of hybrid fuel, hydrogen fuel and other vehicles. Specifically include:
First, before 2015, we will vigorously support the development of key parts of energy-saving and new energy vehicles. In the field of core parts such as motors and batteries, strive to form 3-5 backbone enterprises of key parts such as power batteries and motors, with an industrial concentration of more than 60%. Second, realize the industrialization of ordinary hybrid electric vehicles and strive to have more than 1 million medium / heavy hybrid passenger vehicles.
In order to actively adapt to the 12th Five Year Plan, the connector, as the core component of the automotive industry, must be comprehensively improved. According to the analysis of engineers of linkconn.cn, a professional terminal connector agent, the development of the connector industry has three major trends:
The first is environmental protection, the second is safety, and the third is connectivity.
● environmental protection... Due to the high-voltage system of new energy vehicles, the requirements for connectors are also "seeking common ground while reserving differences" with traditional vehicles. As the new energy vehicle is a "green" vehicle, the connector also requires green environmental protection. In terms of safety, due to the ability of new energy vehicle connector to withstand 250A current and 600V voltage at most, the demand for high standard anti electric shock protection is obvious. At the same time, under such high power, electromagnetic interference is another important problem. In addition, the plugging operation of the connector will produce arc, which will seriously endanger the electrical connection and electronic equipment, and may cause automobile combustion, which requires the special design and development of the connector.
● safety... To meet the high performance requirements of new energy vehicle connectors, it mainly depends on strict design specifications. For example, in case of exposure, it is necessary to prevent air breakdown by high voltage, which requires a certain air gap to be reserved; Under the condition of high voltage and large current, the temperature rise shall not exceed the rated value; When selecting the shell material, we should consider the weight, strength and ease of processing, and how to maintain the stability of the material performance of the connector terminal at different temperatures and how to ensure the necessary conductivity.
● connectivity... Due to the continuous expansion of car entertainment system, the importance of high-speed data transmission function is becoming increasingly prominent. For example, in some models, the camera head is installed on the reversing mirror, which can enable the driver to have a wider field of vision, which requires the connector to transmit more data. Sometimes a connector is needed to solve the problem of transmitting GPS signals and broadcast signals at the same time, which requires improving its data transmission capacity. At the same time, the connector also needs to withstand high temperature, because the car engine is usually placed in front of the car. Although there is a firewall for protection, some heat will be transmitted, so the connector should be able to withstand high temperature.
Basic introduction of automobile harness
Automobile wires, also known as low-voltage wires, are different from ordinary household wires. Ordinary household wires are copper single core wires with certain hardness. The automobile wires are copper multi core flexible wires. Some flexible wires are as thin as hair. Several or even dozens of flexible copper wires are wrapped in plastic insulating tubes (PVC), which are soft and not easy to break.
Due to the particularity of the automobile industry, the manufacturing process of automobile harness is also more special than other ordinary harnesses.
The systems for manufacturing automobile wire harness can be roughly divided into two categories:
1. Divided by European and American countries, including China:
TS16949 system is used to control the manufacturing process.
2. Mainly from Japan:
For example, Toyota and Honda have their own systems to control the manufacturing process.
With the increase of automobile functions and the universal application of electronic control technology, there are more and more electrical parts, more and more wires, and the harness becomes thicker and heavier. Therefore, advanced vehicles have introduced can bus configuration and adopted multi-channel transmission system. Compared with the traditional wire harness, the multi-channel transmission device greatly reduces the number of wires and connectors, making the wiring easier.
Commonly used
The common specifications of wires in automobile harness include wires with nominal cross-sectional areas of 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 4.0 and 6.0 mm2 (the nominal cross-sectional areas commonly used in Japanese cars are 0.5, 0.85, 1.25, 2.0, 2.5, 4.0 and 6.0 mm2). They all have allowable load current values and are equipped with wires for electrical equipment with different powers. Taking the whole vehicle harness as an example, the 0.5 specification line is applicable to instrument lights, indicator lights, door lights, ceiling lights, etc; 0.75 specification line is applicable to license plate lights, front and rear small lights, brake lights, etc; 1.0 specification line is applicable to turn signal lamp, fog lamp, etc; 1.5 the specification line is applicable to headlights, horns, etc; The main power line, such as generator armature line, grounding wire, etc., requires 2.5 to 4 mm2 wires. This only means that for ordinary cars, the key depends on the maximum current value of the load. For example, the grounding wire and positive power wire of the battery are special car wires used alone. Their wire diameters are relatively large, at least more than ten square millimeters. These "Big Mac" wires will not be incorporated into the main harness.
array
Before arranging the harness, draw the harness diagram in advance. The harness diagram is different from the circuit schematic diagram. The circuit schematic diagram is an image describing the relationship between various electrical parts. It does not reflect how the electrical parts are connected with each other, and is not affected by the size and shape of various electrical components and the distance between them. The harness diagram must take into account the size and shape of each electrical component and the distance between them, and also reflect how the electrical components are connected to each other.
After the technicians of the wire harness factory made the wire harness wiring board according to the wire harness diagram, the workers cut and arranged the wires according to the provisions of the wiring board. The main harness of the whole vehicle is generally divided into engine (ignition, EFI, power generation, starting), instrument, lighting, air conditioning, auxiliary appliances and other parts, including main harness and branch harness. The main harness of a whole vehicle has multiple branch harnesses, just like tree poles and branches. The main harness of the whole vehicle often takes the instrument panel as the core part and extends forward and backward. Due to the length relationship or convenient assembly, the harness of some vehicles is divided into front harness (including instrument, engine, front light assembly, air conditioner and battery), rear harness (tail lamp assembly, license plate lamp and trunk lamp), roof harness (door, ceiling lamp and audio horn), etc. Each end of the harness will be marked with numbers and letters to indicate the connection object of the wire. The operator can see that the mark can be correctly connected to the corresponding wires and electrical devices, which is particularly useful when repairing or replacing the harness. At the same time, the color of the wire is divided into monochrome wire and two-color wire. The purpose of the color is also specified, which is generally the standard set by the car factory. China's industry standard only stipulates the main color. For example, it stipulates that single black is specially used for grounding wire and red is used for power wire, which can not be confused.
The harness is wrapped with woven thread or plastic adhesive tape. For safety, processing and maintenance convenience, woven thread wrapping has been eliminated and is now wrapped with adhesive plastic tape. The connection between harness and harness and between harness and electrical parts adopts connector or lug. The connector is made of plastic and is divided into plug and socket. The wire harness is connected with the wire harness with a connector, and the connection between the wire harness and electrical parts is connected with a connector or lug.
Material Science
The requirements for materials of automobile harness are also very strict:
Including its electrical performance, material emission, temperature resistance and so on, the requirements are higher than the general harness, especially those related to safety: for example, the harness of important components such as direction control system and brake, the requirements are more strict.
Function introduction of automobile harness
In modern automobiles, there are many automobile harnesses, and the electronic control system is closely related to the harness. Someone once made a vivid analogy: if the functions of microcomputer, sensor and actuator are compared with human body, it can be said that microcomputer is equivalent to human brain, sensor is equivalent to sensory organ, and actuator is equivalent to motor organ, then the harness is nerve and blood vessel.
Automobile harness is the main network of automobile circuit. It connects the electrical and electronic components of automobile and makes them function. Without harness, there will be no automobile circuit. At present, whether it is an advanced luxury car or an economical ordinary car, the wiring harness is basically the same in form, which is composed of wires, connectors and wrapping tape. It should not only ensure the transmission of electrical signals, but also ensure the reliability of the connecting circuit, supply the specified current value to the electronic and electrical components, prevent electromagnetic interference to the surrounding circuits, and eliminate the short circuit of electrical appliances. [1]
In terms of function, the automobile harness can be divided into two types: the power line carrying the power of the driving actuator (actuator) and the signal line transmitting the input command of the sensor. The power line is a thick wire that carries large current, while the signal line is a thin wire that does not carry power (optical fiber communication); For example, the cross-sectional area of the wire used in the signal circuit is 0.3 and 0.5mm2.
The cross-sectional areas of wires for motors and actuators are 0.85 and 1.25mm2, while the cross-sectional areas of wires for power circuits are 2, 3 and 5mm2; Special circuits (starter, alternator, engine grounding wire, etc.) have different specifications of 8, 10, 15 and 20mm2. The larger the cross-sectional area of the conductor, the greater the current capacity. In addition to considering the electrical performance, the selection of wires is also restricted by the physical performance when on-board, so its selection range is very wide. For example, the frequently opened / closed door on a taxi and the wire across the body should be composed of wires with good flexural performance. The conductor used in high temperature parts generally adopts the conductor coated with vinyl chloride and polyethylene with good insulation and heat resistance. In recent years, the use of electromagnetic shielding wires in weak signal circuits is also increasing.
With the increase of automobile functions and the universal application of electronic control technology, there are more and more electrical parts and wires. The number of circuits and power consumption on the automobile increase significantly, and the harness becomes thicker and heavier. This is a big problem to be solved. How to make a large number of wire harnesses in the limited automobile space, how to arrange them more effectively and reasonably, and how to make the automobile wire harness play a greater role has become a problem faced by the automobile manufacturing industry.
Production technology of automobile harness
With the continuous improvement of people's requirements for comfort, economy and safety, the types of electronic products on the automobile are also increasing, the automobile harness is becoming more and more complex, and the failure rate of the harness is also increasing accordingly. This requires improving the reliability and durability of wire harness. Many people are interested in the process and production of automobile wire harness. Here, you can make a simple description of the knowledge of automobile wire harness process and production. You only need to spend a few minutes to read it.
After the two-dimensional product drawing of automobile harness comes out, the production process of automobile harness should be arranged. The process serves the production. The two are inseparable. Therefore, the author combines the production and process of automobile harness.
The first station of wire harness production is the opening process. The accuracy of the opening process is directly related to the whole production progress. Once there is an error, especially the short opening size, it will lead to rework of all stations, time-consuming and laborious, and affect the production efficiency. Therefore, when preparing the wire opening process, we must reasonably determine the wire opening size and stripping size of the conductor according to the requirements of the drawing.
The second station after opening the line is the crimping process. The crimping parameters are determined according to the terminal type required by the drawing, and the crimping operation instructions are made. If there are special requirements, it is necessary to indicate them on the process documents and train the operators. For example, some wires need to pass through the sheath before crimping. It needs to pre assemble the wires first, and then return from the pre assembly station before crimping; In addition, special crimping tools are used for puncture crimping, which has good electrical contact performance.
Then comes the pre assembly process. First, prepare the pre assembly process operation manual. In order to improve the general assembly efficiency, the pre assembly station should be set for complex wire harnesses. Whether the pre assembly process is reasonable or not directly affects the efficiency of the general assembly and reflects the technical level of a craftsman. If the preassembled part is less assembled or the assembled wire path is unreasonable, it will increase the workload of the general assembly personnel and slow down the speed of the assembly line, so the technicians should often stay on the site and constantly summarize.
The final step is the final assembly process. Be able to compile the assembly platen designed by the product development department, design the specifications and dimensions of tooling equipment and material box, and stick the numbers of all assembly sheaths and accessories on the material box to improve the assembly efficiency. Prepare the assembly contents and requirements of each station, balance the whole assembly station, and prevent the situation that the workload is too large and the speed of the whole assembly line is reduced. To achieve the balance of working positions, the process personnel must be familiar with each operation, calculate the working hours on site, and adjust the assembly process at any time.
In addition, the harness process also includes the preparation of material consumption quota schedule, man hour calculation, worker training, etc. because the technical content value is not high, these will not be described in detail. In a word, the content and quality of automotive harness in vehicle electronic technology has gradually become an important index to evaluate vehicle performance. Automobile manufacturers should pay special attention to the selection of wire harness, and it is also necessary to understand the process and production of automobile wire harness.
