3 Fundamentals of press design

Press types and press construction
ing the correct distribution of material and configuration of transitional
radii between the bed and uprights, as well as between the uprights and
press crown, it is possible to avoid exceeding the maximum permissible
stress levels, also at rated force. Another benefit of FEM-calculated components
is the ability to save on material not needed to ensure rigidity.
On top of the press bed lies the bed plate (bolster plate) used to center
and hold down the lower half of the die (Fig.3.1.1and cf. Sect. 3.4). The
bolster plates on the press bed and the slide are screwed into place to
allow simple removal, for example to alter the T-notch configuration, to
retrofit hydraulic clamping devices or to adapt the openings to new
pressing requirements.
3.1.2 Slide drive
The press frame absorbs all the forces acting on the press, and guides
the slide together with the upper die. The slide, which is moved in the
vertical direction by a drive system acting in the press crown, transfers
the forming or blanking force to the die. Alongside this type of top driven
press, there are presses whose drive system is located in the press
bed. This type of bottom-driven press is used primarily for solid forming,
specifically as coining presses (cf. Fig. 3.2.5). A basic difference exists
between displacement-related, force-related and work-related presses. The
one-pointconfiguration two-pointconfiguration four-pointconfiguration
Fig. 3.1.3 Connecting rod forces at the slide in one-, two- and four-point presses
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
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