In the design of the rear door of the car, often only a shallow definition: the outer plate depends on the shape, the inner plate structure should be strong, the strengthening plate local strengthening, to meet the needs of the installation function, do the above. In fact, the design of the inner and outer plate and the structure of the reinforcing plate itself is very important, but the arrangement relationship between the three is more important. Good structure arrangement relationship, not only can optimize its own structure, but also improve its use efficiency, so as to produce "1+1" is far greater than "2" effect, at the same time may reduce the weight of the assembly, improve the sheet metal process. With the continuous increase of the radian of the back door, the traditional structure of the inner plate, the outer plate and the strengthening plate can not meet the requirements of rigidity and technology at the same time. As is known to all, the back door in sheet metal forming part of overall modelling at the same time, need corresponding rigid to support its accessories installation and reliability, but also need to sheet metal stamping manufacturability, which can be made, but the market demand for the back door radian and area are getting bigger, lead to stamping depth darker, traditional design can't meet the demand of manufacturability and rigid at the same time.

  The advantage of this new material product is that, aiming at the problem of insufficient torsional rigidity and bending rigidity of the back door in the existing design process, a new structure of automobile back door assembly structure is innovatively proposed.