Abstract

Sheet metal forming plays an important role in industry nowadays. Drawing is a popular processing for the sheet mental forming. The drawing process is difficult to control because of many factors affecting the whole forming process. In order to solve the problems encountered in practice, some new methods have been invented. This paper reviews various patents of suppressing defect through adopting new structure and new device in recent years, especially the patents on the drawing die structure with floating punch by hydraulic pressure. In addition, this article introduces a method to solve the problem by applying a new structure. These new structures, which are appropriate for the characteristics of the product, adjacent to each other and the forming depth is deep. The article also introduces a method to solve this problem. The new structure has one or more floating punches with the hydraulic pressure according to the characteristics of the product. During the process of sheet mental forming, The drawing force is put on the floating punch, which makes the sheet mental flow into the cavity of the die. Meanwhile the force provided by hydraulic varies according to the curve because that different status of forming needs different forces. The floating punch has a guide post to assure the precision of up-down moving. Comparing with traditional die structure, the new structure can increase the forming depth of adjacent characteristics and reduce the number of drawing. Therefore, the method is useful and the cost can be reduced.

Keywords: Drawing die, floating punch, hydraulic pressure, sheet metal forming