Platen-Printing Presse
Year: 1887

page_text: We, WILHELM HEIDENHAIN of Berlin and HERMANN HOFFMANN of Magdeburg,
doing business under the firm "Heidenhain & Hoffmann" of Berlin, Germany,
Manufacturers, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
Our invention relates to Platen-Printing Presses and has for its object to lift off
single cards or enveloppes from a pile or pad and to bring them within reach of the
stamp by a new tripping mechanism, whereby the main shaft is released from the
pressure of the stamp.
These improvements are shown in the accompanying drawings of which
Fig. 1 is an elevation partly in section of a platen printing-press being provided
with our new devices and showing the position of the platen, when it receives a new
card or enveloppe.
Fig. 2 represents the same elevation with the platen ready in position for printing.
Fig. 3 is an enlarged plan view of the card lifter.
Fig. 4 shows the same in section on line xc of figure 3.
Fig. 5, 6 and 7 are sections on line y y of figure 8, showing a modification of the
lifter in three different positions and
Fig. 8 illustrates a plan of this modified lifting-off device.
The device for lifting off single cards from the pile is shown in figure 1-4, it
consists in the main of a support for the pile of cards and in a revolving knife which
lifts off a single card at each turn of the shaft on which the knife is mounted.
This knife a has to take one card only and consequently its projection from the
shaft must be equal to the thickness of one card. The shaft b, as can be seen in
figures 3 and 4, consists of two parts, screwed together by screws é, and receives the
knife, which may thus be adjusted according to the thickness of the card. The
rotation of the shaft is transferred from the shaft d, which actuates the tripping
mechanism, to the shaft by means of pulleys and belt, so that at each revolution of
this main shaft d one enveloppe will be taken from the pile.
When the knife a touches the margin of the lowest card, the latter will rest in the

page_text: angle which is formed by the periphery of the shaft and by the projecting piece of the
knife, and when the shaft bis turning further on, the card will fall down and will be
held by the catcher e which is of the common construction used in printing
presses.
As can be seen, the pile of the cards & is standing oblique and is resting on a plate
or frame and is leaning at the upper end against the shaft b. The pile is also
weighted by a weight g, so that it always goes further down, when a card is
taken off.
A modification of our sheet-lifting-device, adapted to be used for enveloppes is
shown in figure 5-8. The pile of enveloppes are also set in an oblique plain and
is guided by the same means and also weighted by the weight g. But instead of
the rotating knife is arranged a pair of tongs which catch the enveloppe at the
locking-edge and bend it in the manner shown in Fig. 4, in what position the
enveloppe is taken away by the above mentioned catcher of the tripping mechanism.
The tongs consist of a bar z to which is pivoted the tong ¹. The bar is guided
parallely to the enveloppes between plates and i which are part of the frame fand
are held by springs which serves as a brake. The part 1 of the tongs is connected
with the main driving shaft d by a rod 1, which is pivoted excentrically to the shaft
or to a disk mounted on shaft d. At their upper margins the enveloppes rest on
and are guided by the angle-iron m, from which but one enveloppe is pulled away by
the tongs ¹.
This is done in the following manner:
When the connecting rod 7 is in its lowest position, as indicated by figure 5, the
tongs will be opened, when however the rod is in its highest place the tongs
will have closed and will have moved up, so that the enveloppe is held between the
tongs, as is illustrated in figure 7. The enveloppe is held by the tongs, even while the
rod is going downward and consequently it will be bent off from the pile so that
it can be readily taken away by the catcher e of the tripping mechanism (see
figure 8).
0,
The shaft of the tripping' mechanism heretofore used in platen printing presses,
had to carry all the pressure of the stamp, so that the platen often tipped over by
said pressure.
We avoid this by giving to the platen a rest on a standard which
has an inclined plain at. its top (see fig. 1 & 2) and we also give the same inclination
to the bottom side of the plate p, so that the top side of the latter will be horizontal
when gliding on the standard o.
The tripping device consists in the main of a crank g being mounted on the
driving shaft d, a cylindre », in which works a piston r, and the swinging standard s
pivoted at t. Inside the cylinder is arranged a spiral-spring r, which constantly
presses the piston in the direction to the swinging standards, the purpose of which
will be herein after described.
At
When the platen is in the position to receive a card or enveloppe as is shown in
figure 1 the catcher e will hold the sheet on the platen p and the piston-rod r₁, to
which the standard of the platen is connected, will project so far, that the piston r₂
rests against the cap r of the cylinder 1. By the rotation of the shaft d in the
direction, indicated by the arrows in figs. 1 & 2, the crank will have moved into the
position fig. 2 and the platen p has glided along on the inclined top of standard o.
the same time the stamp is coming down which keeps the types and does the
printing on the card etc. If the connecting link between the crank q and the
pivoted standards was not made flexible, the platen would only stand still a very
short time to have the printing done on the card etc. which it keeps by its catcher e,
but in machines provided with our new improvement the platen is pressed wedgelike
on the inclined top of the standard o and is held for a consederably longer time than
was heretofore possible. Hereby the spring 7 is compressed and when the crank
is turning further down the spring will first be expanded, before the platen is moved
back from the standard o. Thus the print will be done to a great nicety and the
main shaft d will be released from the strong pressure of the stamp u and it will never
happen that the catcher e takes two or more card etc. away from the pile.

page_text: Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed, we declare that what we claim is:
In platen-printing-presses:
1.) The apparatus for lifting of single cards from a pile consisting of a frame on
which the cards are obliquely resting in combination with a knife the projection or
the thickness of which is equal to the thickness of one card, all substantially as
described.
2.) The apparatus for lifting off single cards from a pile consisting of a frame on
which the cards are obliquely resting and are pressed down by a weight, in com-
bination with a rotating knife being mounted on a shaft, the projection of which
knife is equal to the thickness of one card, all operating substantially and in the
manner as described.
3.) The modified apparatus for taking off single enveloppes from a pile consisting
of a frame on which the enveloppes are obliquely resting and are pressed down by
a weight in combination with a pair of tongs of which the one is guided parallely
to the enveloppes and the other is actuated from the main driving shaft by means
of a connecting rod, all operating substantially and in the manner as described.
4.) The tripping mechanism which oscillates the platen, consisting of a crank
pivoted to a cylinder which is provided with a piston and with a spring and of a
pivoted standard to the top of which is fixed the platen with an inclined bottom,
in combination with a standard being provided with an inclined top side to receive
the platen for the purpose of releasing the main driving shaft from pressure and
to allow a longer pressure of the types on the article to be printed, all substantially as
described.