3 Fundamentals of press design

242 Sheet metal forming and blanking
ical solution is to integrate a large-panel transfer press into the production
process when a model change is made and when new die sets have
to be manufactured.
Die change
In large-panel transfer presses, dies are also exchanged using moving bolsters
which move automatically in and out on the left and right of the
press, in some cases simultaneously (cf. Fig.3.4.4). The die change area is
safeguarded by light barriers and partially monitored by video cameras.
The die changeover sequence is depicted in a die change diagram.
Initially, the part-specific contoured nests of the intermediate stations
are automatically transferred to the moving bolster. The part of the
gripper rails between the uprights to which the part-specific grippers
are attached, must be exchanged as part of the die change process.
pressure
pins
diecushion
box
pressure
column
liftingbridge
displacement
cylinders
liftingcylinder
Fig. 4.4.33 Hydraulic four-point draw cushion with pressure pins
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998