Research on the switching between the sealing and non sealing state of automobile panel die

In the design and development of automobile panel die, in order to meet the market demand for various vehicle types and configuration, a set of mold is required to be compatible with the production of various parts at the same time. Such mold design can improve the production efficiency and reduce the mold manufacturing cost.
The common switch between the closed window state and the non closed window state is shown in Figure 1. In the actual production process, due to the influence of inventory and production plan, one state of parts production inventory can not be too much, and the two states of parts interpenetrating production, resulting in frequent mold switching. In the state switching between the sealed and non sealed mold, there will be some problems, such as inaccurate positioning of the window sealing parts, poor surface quality of the sealing parts, easy wrong assembly of the operator, missing of the mold parts, position deviation of the mold parts, and unclear mold state. In this paper, through the analysis of the causes of the problem, take reasonable measures to ensure the quality of parts in the production of mold switching state.
Figure 1 parts in unsealed and sealed state of a vehicle
Inaccurate positioning of window sealing parts
In the mold of door structure, the positioner of the part is usually set in the window frame, and the edge of the part window frame is clamped by the positioner, which can effectively play the role of positioning and prevent the part deviation in the process of discharging. When the non sealing die is switched to the closed window state, the original positioning of the part window must be removed, so the parts can only be positioned by the mold surface in the mold cavity. In the production, the rhythm is fast, and the parts are often not placed in place and the positioning is not accurate. In light, the parts are unqualified, and in serious cases, they are scrapped.
How to ensure the accurate positioning of parts in the production of sealed windows and doors determines the quality of parts. The following is an example of a vehicle’s tail door panel to illustrate the solution to this problem. The part cannot be positioned through the contour surface of the product, because there is a wedge on the upper part of the op40 mold window frame, and the positioner cannot be installed, as shown in Fig. 2. Affected by the gravity of the window frame, the whole part of the window sealing part often moves upward in the process of automatic production, which results in the parts not in place, flanging and curling, and the parts are scrapped. In order to solve this problem, the positioning of parts must be controlled. Through verification, the following measures are taken.
Fig. 2 die structure of a vehicle in sealing state
(1) through the analysis, it is impossible to add positioner on the mold. In order to reduce the offset of parts during discharging, other methods must be adopted. Through measurement, it is found that there is a height of 40mm between the manipulator discharge point and the mold surface. When the part is put down, due to the gravity, the front end of the mold will be offset, and there is no locator at the front end of the mold, so the positioning of the part will be inaccurate. By changing the position of the discharging point of the automatic path from 40mm to 20mm, the position of the discharging point is reduced, and the parts are laid down in accordance with the mold surface, so that the parts can be discharged more stably.
(2) due to the rapid production rhythm, there are 10 strokes per minute. If the suction cup on the manipulator end pick-up is not tight enough, the parts will slide with the suction cup in the transmission process, resulting in inaccurate discharge. In view of this situation, the suction cup of the end picker of the part is replaced by a double-layer suction cup with a single-layer suction cup with greater suction force, as shown in Fig. 3. After the implementation of the above two measures, 2000 parts were verified in production, and the problem was solved.