Spiral nut plays an important role in battery connection for electric and hybrid vehicles

If the battery life and overheating of EVs can be solved, EVs and hybrid technologies will play a critical role in the government's nearly doubling of fuel economy standards. Then the innovative application of the screw connection fixing mode to improve connection reliability may become an important way to solve battery life and overheating problems.汽车 When automobile manufacturers use various technologies to improve fuel economy, electric vehicles and hybrid vehicles are more attractive to support environmentally friendly customers because they want to reduce or limit fuel consumption. The energy generated by the battery on electric and hybrid vehicles is roughly equivalent to the energy produced by less than 8 liters of gasoline. Therefore, in order to effectively use each milliamp of electricity without generating heat, it is technically necessary to Great effort. In order to fulfill the promises of electric vehicles and hybrid technologies to automobile manufacturers to reduce fuel consumption, battery conductivity, connection reliability and life need to be improved. Perhaps the innovation of a screw-locking method is the key to solving these problems. However, it is difficult for ordinary fasteners to ensure the battery's conductivity and connection reliability, because ordinary fasteners can easily lose the pre-tightening force. According to research by STANLEY engineers, long-term vibration and thermal cycling of cars, ordinary fasteners will quickly attenuate 50% of the pre-tension. Lithium or acid groups of electric cars and hybrid cars are connected in series. If one of the connections fails due to loose threads, it means that not only one battery is lost, but that a whole series of batteries have failed.严重 Another serious problem is that when the pre-tightening force of the battery fixing fasteners of electric vehicles or hybrid vehicles disappears, the battery will lose its ability to supply power. Sufficient power supply current will inevitably generate heat and cause arcing, which is a potential threat to fire. In order to ensure sufficient pre-tightening force and the integrity of the connecting member from the battery arrangement to the battery end to improve the battery's conductivity, the engineer found a solution is to use a nut called Spiegel. Due to the limitation of the 60 ° thread structure, the traditional anti-loosening fastener cannot avoid the basic problem of loosening, that is, there is a gap between the tip of the male thread and the bottom of the female thread, which will cause vibration-induced loosening, which will cause the pretension force to decay And promote the heating of battery and electric vehicle and hybrid vehicle connection parts. The stress concentration and fatigue strength reduction of the first few threads are another serious problem, especially on relatively soft metals, where the axial force of the threads causes them to undergo severe shear. The increase in temperature will cause thermal expansion and contraction of the material or surface, which is also a potential threat to the looseness of the battery connection. Regarding the above problems, the engineer has perfectly solved the problem of traditional fasteners by introducing Spirax nuts. This method has been applied to the power supply systems of electric vehicles and hybrid vehicles for more than 5 years, and has been applied to aviation battery systems for more than a decade. The reason why Spiegel nuts have such a reliable anti-loosening performance is that the 30 ° wedge thread structure, that is, a 30 ° bevel is designed on the thread bottom of the nut. When it interacts with the external thread of the bolt, it causes the external The cusp of the thread is slightly deformed to the 30 ° inclined plane, forming a fully threaded ribbon contact called a spiral line. This thread contact method makes the pre-tensioning force more evenly distributed on the entire thread, instead of focusing on the first few threads, thereby improving the ability to resist lateral vibration loosening, increasing axial torsional load and fatigue strength, and preventing excessive temperature . Because this structure improves the effective pre-tensioning force by 30% compared with ordinary threads, the contact at the end of the battery is better, the conductivity is more guaranteed, and the better the power supply efficiency. Improving the effective pre-tightening force and conductivity can not only help the tight connection between battery cells of electric vehicles and hybrid vehicles, but also help the battery to be connected stably in the power supply system. At the same time, it can also essentially help the connection from a single battery cell to multiple battery cells. This multi-stage connection may provide high current and high power electric vehicle and hybrid vehicle power supply systems.的 In the application of electric vehicles and hybrid vehicles, some parameters need to be changed according to the change of connection status. Engineers would probably assume that removing large, bulky aero-engines would eliminate the need for vibration and special fasteners, but the opposite is true. Automotive manufacturers have gone through a long process of selecting traditional steel to aluminum alloys in terms of material selection, in order to reduce the weight of electric vehicles and hybrid vehicles. In fact, aluminum alloy is a relatively hard material, which can transmit vibration force more quickly than steel. In this case, the anti-loosening performance of the fastener and the good conductivity design are the prerequisites for calculating the magnitude of anti-vibration force.施 Several leading institutions have conducted testing and research on Spirax locknuts, including MIT, Goddard Space Flight Center, Lawrence Livermore National Laboratory, and British Aerospace Corporation. In automobiles, Spirax anti-loosening nuts are used in many applications, such as ring gears, torque converters, exhaust pipes and axles mounted on chassis, turbine engines, gearboxes, and diesel engines. Of course, there are some extreme applications, such as one-time assembly, which cannot be changed. Unlike traditional fasteners, which rely on external locking features, they will generate unnecessary debris, peeling, and additional stacking heights. The internal locking feature of Spitzer nuts can avoid the above problems caused by ordinary nuts. Because the Spiegel nut is freely rotatable, it can be easily screwed into the bolt with your fingers, so no debris, chips or powder will be generated. This well meets the required clean environment for battery manufacturing and reduces the potential risk of arcs caused by debris. Regardless of the type of battery, the key to the design is to ensure the efficient transmission of point-to-point current for electric vehicles or hybrid vehicles, without causing loosening of fasteners during the entire life cycle. Spirax nut can solve this problem perfectly.