The same maker has thought of moving the mould upwards by a system of cranks (Fig. 164). The cap being fixed, the working of this machine causes less violent shocks than in the previous ones; it can therefore be worked in any storey of the drying-rooms.
Fig. 165. Stamping Press (Joly).
Fig. 163 represents an English press in which the parts are made extremely simple; the sketch sufficiently explains the machine.
The machine represented in Fig. 166 is typical of the German kind of press; its working Is less simple and less rapid than that of the French kind, and nearly all German makers manufacture the latter (see Figs, 159 and 160).
It is easy with stamping presses to stamp the faces of the bricks in depression or relief; it is sufficient to provide the plates of the cap and bottom with the design in relief if we wish to have it depressed, or in depression if we want it in relief.
Nevertheless, if we want clear-cut reliefs, it will be necessary to maintain the pressure longer than a stroke of the lever can effect. This result is obtained by using the Whitehead press (Fig. 167).
The operation is performed by means of an endless screw driven by a flywheel and handle.
The Jager press (Fig. 168) is composed of a piston with up and down motion which compresses the brick in the mould,
Fig. 166. Stamping Press, German Type (Jacobi).
Fig. 167. Special Press (Whitehead).
This motion is communicated to the piston by a crank and a system of bent shafts and cog-wheels as shown in Fig. 168.
Like those worked by hand, this press can also stamp any kind of ceramic produc\t; it will be sufficient to change the moulds and substitute others suited to the shape and nature of the articles to be stamped. Screw and friction-plate presses as used for the manufacture of tiles can also be used for bricks. Fig. 169 shows a press of this kind fitted with a brick-mould.
Steam stamping presses are very little used because it is easy to remove hand-presses when the circumstances of manufacture require it, and because the latter have as large an output as the former.