The rapid development of the global economy and the continuous advancement of industrial technology have made the vehicle industry in a state of continuous development. The increase in car ownership has also consumed a large amount of petroleum resources. Severe energy crisis and environmental pollution are urgent issues^[1]. According to experts' estimates, the global population will increase to 10 billion in the next 50 years, while the number of car ownership will increase from 1.2 billion to 2.5 billion^[2]. Consumption demand will far exceed the global energy surplus. At the same time, carbon dioxide emissions in 2014 reached 40 billion tons, and the climate warming issue poses a great threat to human survival. While the automobile industry serves the industrial development and human life, the three major issues of energy, safety and environmental protection also follow. . The new automobile field of electric vehicles is a new concept energy vehicle proposed to solve the problems brought about by traditional fuel vehicles. Electric vehicles can effectively alleviate the problems of energy depletion and environmental pollution, and can also meet the production and living needs of people^{[3 , 4]}.

In the development of electric vehicles, the development of the drive axle is extremely important. The performance of the drive axle can largely determine whether the vehicle design is reasonable^[5]. In June 2012, the State Council issued the “Energy Conservation and New Energy Vehicle Industry Development Plan (2012-2020)” which emphasizes the acceleration of the development of new energy automotive industry and focuses on the industrialization of pure electric vehicles and plug-in hybrid vehicles. To promote the target and vigorously develop electric vehicles, parts and supporting infrastructure, there is still a large gap between domestic and foreign countries in the design technology of electric vehicle drive axles. So far, China has no clear national standards for the performance requirements of the electric vehicle drive axle design. In the design process of the drive axle, it is necessary to refer to the national standard of the fuel automobile drive axle. The lack of a clear national standard also leads to the domestic electric vehicle drive axle. The important reason for the slow development.

With the increasingly serious urban pollution and energy shortages, new energy vehicles, especially pure electric vehicles, have entered the fast lane of development. Local governments have introduced relevant policies and supported them. They hope that the pure electric industry will be more grounded and accepted by the majority of users. Compared with ordinary cars, trucks travel longer hours and consume more energy and costs. Therefore, the development of pure electric trucks is more meaningful for the implementation of national energy-saving emission reduction targets. Pure electric trucks are favored by the government because of the advantages of green environmental protection and zero pollution. Countries have introduced policies or given certain financial support to encourage their development. With the joint efforts of the government and enterprises, pure electric trucks have indeed formed a kind of wind direction in the industry. People also seem to see the dawn of zero emissions.

This paper aims at the characteristics of pure electric vehicles, and obtains the preliminary data of various components and checks the drive axle design. Through the three-dimensional design soft UG, the three-dimensional model of each component of the drive axle is obtained, and the non-interfering assembly between the components is completed and the total number of drive axles is obtained. Into a model.

The development of pure electric trucks in China started relatively late, and the experience in technology and product promotion is still not enough. Compared with domestic and foreign countries, it is much earlier to go purely electric and there are lessons to be learned from various aspects.

Since 2004, the number of electric vehicle manufacturers at home and abroad has dramatically increased, and battery production and control technologies have been continuously updated^[6]. In recent years, domestic electric vehicles have developed rapidly. With the strengthening of government support, the competitiveness of the domestic electric vehicle industry has greatly increased^[7,8]. In the early stage of the development of electric vehicles, the structure of the drive devices was generally the same as that of conventional fuel vehicles. At that time, the motor control technology was underdeveloped, and the structure still had transmissions and clutches. The structure of the drive axle was the same as that of the fuel vehicle drive axle, except that the engine was replaced with an electric motor^[9]. This modified electric vehicle can increase the starting torque of the electric vehicle at the start and increase the backup power at low speed, but the electric vehicle itself is too heavy and causes unnecessary waste of energy. With the continuous development of motor design and control technology, clutches and transmissions have been eliminated in the overall layout. Only one set of motors and inverters are required. Although this arrangement has a higher design requirement for the motor, it is greatly reduced. The quality of automobiles improves the efficiency of energy transmission and increases the driving range ^[10].

The U.S. government has fully provided corporate funding and policy support for the development of pure electric projects. In the past few years, pure electric trucks in the United States have developed in various degrees in heavy-duty trucks and light trucks. The speed has been significantly improved, and the endurance capacity has been somewhat insufficient, which is about 160 kilometers. However, technological advancement has been accompanied by various new energy policies that the government has continuously pushed for, so that pure electric trucks have a place in the truck industry. Over the years companies have invested a lot of human and material resources to upgrade and upgrade the same product. Market attention^[11].

Pure electric trucks are limited by charging time and cruising range. Currently, they are mainly used for point-to-point short-distance transportation. They cannot yet truly replace the internal combustion engine truck and achieve long-distance transportation requirements^[12]. After years of research and development abroad, it still cannot effectively increase the mileage of pure electric trucks. This is a fatal blow to long-distance transportation and is also the key to limiting its popularity. Despite this, several major truck brands in Europe have pure electric products. This shows that the application of pure electric trucks has become a trend within the industry and cannot be overlooked.

The pure electric trucks still has a long way to go.