An Improved Sheet Delivery Device for Printing Presses.
Year: 1899

page_text: Date of Application, 20th Mar., 1899-Accepted, 17th June, 1899
COMPLETE SPECIFICATION.
An Improved Sheet Delivery Device for Printing Presses.
I, AMBROS BOHN, of Würzburg, Germany, Manufacturer, 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:-
My invention relates to a sheet delivery device for delivering the sheet unturned
and printed side up, and preventing at the same time the printed side of the sheet
coming in contact with any parts of the press, in order to avoid blurring of the
print and prevent offset.
The object of my invention is to provide a delivery device indifferently applicable
to any material to be printed upon, as common paper, thick paper, card board, tin
plates, sheet metal and the like; and I attain this object, first, by dispensing
with the necessity of turning the sheet to be delivered, so as to eliminate the
influence of the weight of the material to be printed upon, and, second, by prevent-
ing the print coming in contact with any part of the press, so as to be independent
of whether the ink will be easily absorbed by the material to be printed upon, or
not so.
In the accompanying drawing I have represented my invention diagrammatically
and in connection with a printing press of which I have indicated only the main
parts, an impression cylinder 1, a form cylinder 1, a transfer cylinder 2 and a
delivery drum 3, my invention not being restricted to be applied to such a press,
but being obviously applicable to any press, as will be seen by the following
description thereof.
In the present instance the sheets printed between the impression cylinder 1
and the form cylinder 1' are received and transferred by the transfer cylinder 2
to the sheet delivery drum 3, from which they are delivered as commonly to
stationary tapes 4 and 5 running continuously in one and the same direction.
The upper tapes 4 can be dispensed with, in general, and are only indispensable
when using very thin paper to be printed upon.
A set of swinging tapes 6 is provided in line with the tapes 5, tapes 6 being
supported by two arms 7 fixed at one end on a spindle 8, which is journaled in
the frame work, and carrying the tape rollers 9 at their other end. Tape rollers 10
are loosely provided on spindle 8 supporting each a pair of tapes 5 and 6, thus the
tapes 5 being driven from the drum 3 and at the same time driving the tapes 6.
A short lever arm 11 is mounted on spindle 8 and connected by a rod 12 to
a bell crank lever 18 which is pivoted to the frame work and pressed with a
roller 15 against the edge of a cam disk 10 on shaft 17 by means of a spring 14
actuating rod 12. By these means, as the form cylinder 11 revolves, arms 7
with the tapes 6 will be alternately reciprocated from its lowered position
represented in full lines to its raised position indicated by dotted lines, and back
again to the former, remaining, however, for a comparatively long time in the
raised and lowered position respectively owing to the circular portions of the
edge of cam disk 16.
In lieu of connecting, as indicated in the drawing, rod 12 and spinale 8 by

page_text: means of an arm 11, a pinion may be mounted on the spindle, and rod 12
provided with a short rack to engage with the said pinion.
The working of the parts described is as follows:
As the tapes 6 occupy their lowered position, in line with tapes 5, the sheet to
be delivered is forwarded by the tapes, until overshooting rollers 9 with its front
edge and assuming the position indicated by the sheet 19, the front edge of the
sheet being stopped if required by a stop plate 18. As then arms 7 with tapes 6
are swung upwards, the tapes thereby being continuously kept in running con-
dition, the rear end of the sheet will be successively and fully removed from
tapes. 6 and in the same measure deposited on the pile of sheets 20. As then
the tapes remain for a period in their raised position, as heretofore described,
the operator is enabled to place an offset-sheet on the delivered sheet in order
to prevent blurring of the fresh ink by the following sheet and the latter being
blurred by the former. Tapes 6 are then lowered again, and so on.
In order to have the successive sheets always delivered, deposited and stopped
under the same conditions, and secure perfect and uniform piling of the same it has
been found convenient to keep the delivery level invariable, that is to say to lower
the delivery table in the measure as the pile increases.
To this purpose the table 21 is supported by rods 22, which are guided in
arms 23 of the frame work, and loosely connected by links 24 to levers 25, which
are mounted on a shaft 26 journaled in the frame work. A toothed segment 27
is fixed to shaft 26 and engages with a screw wheel 28 journaled in the frame
work and driven by a pair of bevel wheels 29 30. The latter 30 is connected to a
ratchet wheel 31, and a step by step movement is imparted to wheel 31 and
screw wheel 28 by a lever 32 engaging with wheel 31 by a paw! 33. Lever 32
is reciprocated by a rod 34 pivotally connected to a crank arm. 35 of the impression
cylinder shaft 36. The crank is slotted, so as to allow of adjusting the end of
rod 34 within the crank slot, in order to control the stroke of lever 32 and the
corresponding downwards movement of table 21, taking place at each revolution of
the impression cylinder, in accordance with the thickness of the paper or other
material to be printed upon. This downwards movement of the table can be
further controlled by likewise providing lever 32 with a slot, as shown, and
adjusting therein the connecting end of rod 34. Table 21 is raised again by
actuating a crank 39 mounted on the shaft of the screw wheel and at the same
time disengaging ratchet wheel 31 from pawl 33..
Pawl 33 is preferably provided with a projection 37, and this projection is
struck by an abutment 38 of table 21, as soon as the latter has been lowered a
predetermined extent. By these means pawl 33 will be automatically and so
timely released from the ratchet wheel as to prevent lever 25 performing a too
large stroke and consequently leaving its normal working position.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1. In a delivery device for printing presses the combination of a set or sets
of stationary tapes, a set of movable tapes in line with the stationary tapes and 4
projecting above the delivery table, and means for temporarily swinging upwards
the movable tapes and out of line with the stationary tapes, the sheet to be
delivered being forwarded by the stationary tapes and by the movable tapes, when
in line with the former, so as to partially leave the movable tapes and be partially
deposited on the table, whilst the sheet is fully removed from the movable tapes
and fully deposited on the pile by the upwards swinging movement of the movable
tapes thus being retracted from underneath the sheet, the latter by these means
being delivered in an unturned condition, printed side up, and prevented from
coming in contact on its printed side with any part of the press, substantially as
and for the purposes described.
2. A feature of the delivery device claimed under Claim 1, consisting in that the

page_text: delivery table is movably arranged and step by step lowered with the pile
increasing by delivery, in order to keep the delivery level invariable and have
the sheets always delivered under the same conditions, substantially as and for the
purposes described.
3. A lowering device for successively lowering the delivery table, as claimed
under Claim 2, consisting of the combination of a pawl actuated ratchet wheel, a
screw wheel controlled by the same, a toothed segment engaging with the screw
wheel, levers mounted on the shaft of the said segment and pivotally connected
by rods to the delivery table, means for guiding the latter, and means for actuating
the ratchet wheel at each revolution of the impression cylinder, substantially as
and for the purposes described.
4. A feature of the lowering device claimed under Claim 3, consisting in that
the pawl actuating the ratchet wheel is automatically disengaged from the latter
by means of the delivery table as soon as the said table has been lowered a pre-
determined extent, in order to prevent the table actuating levers performing a
too large stroke and thereby leaving its normal working position, substantially as
and for the purposes described.