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Scientific American Supplement, No. 417, December 29, 1883 by Various
page 27 of 98 (27%)
and compression of the carbon is obtained, and the rods or blocks are
delivered through the formers, in a state of greater density and better
quality then hitherto. The machine consists of two cylinders, A A',
placed longitudinally, as shown at Fig. 1, and in reversed position in
relation to each other. In each cylinder works a piston or plunger, a,
with a connecting rod or rods, b; in the latter case the ends of the
rods have right and left handed threads upon which a sleeve, c, with
corresponding threads, works. This sleeve, c, is provided with a hand
wheel, so that by the turning it the stroke of the plungers, a a, and
the size of the chambers, A A', is regulated so that the quantity of
material to be passed through the dies or formers is thereby determined
and may be indicated. In front of the chambers, A A', are fixed the dies
or formers, d d, which may have any number of perforations of the size
or shape of the carbon it is intended to mould. The dies are held in
position by clamp pieces, e e, secured to the end of the chambers A
A', by screws, and on each side of these clamp pieces are guides, with
grooves, in which moves a bar with a crosshead, termed the guillotine,
and which moves across the openings of the dies, and opening or closing
them. Near the front end of the cylinders are placed small pistons or
valves, f f, kept down in position by the weighted levers, g g (see Fig.
2, which is drawn to an enlarged scale), which, when the pressure in
the chamber exceeds that of the weighted levers connected to the safety
valve, f, the latter is raised and the guillotine bar, h, moved across
the openings of the dies by the connecting rods, h', thereby allowing
the carbon to be forced through the dies. In the backward movement
of the piston, a, a fresh supply of material is drawn by atmospheric
pressure through the hoppers, B B', alternately. At the end of the
stroke the arms of the rocking levers (which are connected by tension
rods with the tappet levers) are struck by the disk wheel or regulator,
the guillotine is moved back and replaced over the openings of the
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