Improvements in Multicolor Printing Presses.
Year: 1894

page_text: Date of Application, 8th May, 1894-Accepted, 9th June, 1894
:
CUMI LEIE
DEMOTIVATION.
[Communicated from abroad by EMMA LOUISA FORBES, of 233, Chestnut
Avenue, Jamaica Plain, Boston, Massachusetts, United States of America,
Gentlewoman.]
Improvements in Multicolor Printing Presses.
I, CHARLES AUBREY DAY, Chartered Patent Agent, of 321, High Holborn,
in the County of London, 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 :-
This invention is related to an important class of printing machines intended
for the production of pictures and ornamental delineations in two or more colors;
and more specifically to those adapted to print on sheets of paper, and on the
same side of each sheet, a number of superimposed impressions each with an ink
of such a color as in the aggregate will produce the desired design at every
complete revolution of the press.
In the press which forms the subject matter of the present invention, the
sheet of paper to be printed upon is fed to the impression-cylinder, where it is
taken hold of by grippers and then carried to two form-cylinders with both of
which the impression-cylinder is connected by gearing. These form-cylinders
are of equal size and are provided with an equal number of form-supporting
surfaces. The impression-cylinder after having presented the leading edge of the
sheet upon it to a form on one cylinder, presents it then to the second form in
the series ou the other cylinder, and to the third upon the first cylinder, and so
alternately from one cylinder to the other till the forms are all printed.
In the drawings which are part of this Specification,
Fig. 1 shows diagrammatically the printing press I have invented adapted for
four colors.
Fig. 2 is the same arrangement of parts with a modified delivery.
In these figures 10 is the impression-cylinder; 12 is the first form-cylinder;
14 the second. The gap-spaces on both the latter are marked 16 and the forms
on the same, marked' Nos. 1, 2, 3, and 4 near their leading edges, are the forms for
the several colours. Except for the gap-spaces which correspond in length to the
gap on the impression-cylinder, the whole surface of the form-cylinders is covered
with its forms. 18 is a delivery-cylinder and 20 its grippers, while 22 is the
grippers on the impression-cylinder 10. In these drawings the feed-boards are
marked 24. The tapes 28, and the driving pinion in every case is 30.
My invention in its simplest construction is shown in Fig. 1. In this press
four curved forms, each printing a different color, are arranged on suitable form-
supports; they are numbered No. 1, No. 2, No. 3, and No. 4 and these numbers
are placed at the leading edge of the forms which are divided between the two
cylinders, two on each. When a sheet is fed to the grippers 22 the impression-
cylinder carries it to the first form-cylinder 12, which latter is angularly
adjusted therewith through the gearing on both, so that the leading edge of the
form and the leading edge of the sheet on the impression-surface meet at the
point of contact. This has taken place already in the position shown, the leading
edge having met that of the form No. 1, and gone forward to that of form No. 2,
on the second form-cylinder 14.
This state of things is indicated in Fig. 1, by the heavy line representing
the sheet of paper, which is still partly on the feed-board and half round the
impression-cylinder, receiving the impression from form No. 1, and just about

page_text: to receive that from form No. 2. As the rotation of the impression-cylinder
continues the printing of the second color is begun, before the conclusion of
which the sheet is presented to form No. 3 on the first, and finally to form No. 4
on the second form-cylinder. After this, when the grippers reach the delivery-
cylinder 18 they are thrown open, and the edge of the sheet is grasped by the
grippers 20, and transferred by the apparatus shown with a sheet upon it, to
the tapes 28, from which the fly 26 throws it over on the delivery-board 36,
placed to receive the pile of work. The four sets of inking apparatus used for
this press are marked 31, 32, 33 and 34. In Fig. 1 only one set of form-rollers
has dropped upon the work, namely that marked 34 which inks the fourth form;
all the others are at the time inactive; but forms Nos. 1 and 2, have been
inked already.
In this machine it is apparent the productiveness is very great, for, in the
press shown, four superimposed designs are printed on the same sheet of paper
for every two revolutions of the impression-cylinder, which rapid rate is due to
the fact that one or other of the forms is always being printed as long as the
press works, and that two forms are being printed simultaneously, except while
the four gap-spaces 16 are passing the impression-cylinder.
In Fig. I the delivery of the sheet is accomplished by apparatus consisting of a
delivery-cylinder 18, with tapes 28, and in consequence the sheet runs upon the
latter face down, and is then lifted by the fly and thrown over on the pile of
sheets in the well known way. This procedure, as experience has shown, is
satisfactory when only a few colors have been printed on the paper; but when
many superimposed colors cross each other, the accumulated quantity of wet
ink renders it difficult to carry the sheet on tapes face down and lift it there-
from as explained, without smearing.
I modify the usual methods of feeding and delivery to overcome this difficulty
when it is thought desirable to do so, as shown in Fig. 2. In this drawing the
relative position and dimensions of the form and impression-cylinders is the same
as in Fig. 1, and the number of forms (four) remains also unchanged. But the
direction of revolution is changed and the first form-cylinder 12 is where the
second 14 is in the preceding press. Underfeeding is also resorted to in this case;
the feed-board 24 conducting the sheets to the lower side of the impression-cylinder
where the grippers seize it and carry it to form No. 1 on 12, then to No. 2 on 14;
and so in alternating sequence till, after Nos. 3 and 4 are printed in part, the
delivery begins. For this purpose I use what I will call a belt-delivery by
which the sheet is carried away, in a direction nearly horizontal, from the upper
part of the impression-cylinder by grippers moving in a right line at the proper
speed, and then dropped on tapes 28 which convey it away face up. The belt for
this purpose may consist of non-extensible material of many kinds; of steel bands,
or of two parallel chains 38 as shown in Fig. 2, running on sprocket wheels 40 and
connected by cross bars at intervals, with grippers 42 on certain of the latter
provided at proper distances apart, which close upon the leading edge of the sheet
when the grippers 22 on the impression-cylinder, having reached their highest
point in the second revolution (for a four color press) are thrown open. The
grippers on the endless chain 38, holding the end of the sheet, travel with it
parallel to the endless tapes 28 directly over the latter, both at a surface speed
which is the same as that of the impression-cylinder. When the distance to which
the sheet has been drawn out by this delivery apparatus is sufficient to insure its
onward motion, it is let go by the grippers holding it and the sheet falls upon the
tapes and goes forward to its destination, still at the same speed. When the
next set of grippers 42 pass the impression-cylinder they find another printed
sheet ready to be drawn off the impression-cylinder, and the process above
described is repeated.
In this press, looked at from a practical and economic point of view, it will be
seen, that the delivery apparatus plays an important part, for through its use the
removal of the printed sheet within the interval available is rendered possible, and

page_text: in the case of the belt delivery, with its face up. The amount of effective work
of which the press is capable, bearing in mind the smallness of the whole machine,
is very great, due to the short periods of its comparative inactivity.
In this Specification when reference is made to the "length" of a form, or
form-support, or impression-surface, gap or gap-spaces, the extension of the same
circumferentially in the direction of the run of the press, and at right angles to the
axes of its cylinders, is always meant. By the term " gap-space," that depression
in the face of the impression-cylinder is meant which is necessary for the accom-
modation of the grippers and reel-rods, and also the like depressions in the face of
a form-cylinder made for purposes of correspondence with the impression-cylinder
gap, or to contain requisite straining and clamping-bars &c.
Having fully described my invention, I wish it to be understood, that I do not
confine myself, specifically to the embodiment of the same herein shown, being well
aware that substitute appliances can be devised without departing from the
principle involved.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a multicolor press adapted for printing sheets; an impression-cylinder
provided with a gap and grippers, in combination and in operative contact with
two form-cylinders of equal size, and with one or more form-supports separated by
gap-spaces upon each, one gap-space and one form-support being equal in length to
the circumference of the impression-cylinder; and with an endless delivery-belt of
flexible material carrying grippers, and adjusted and timed to seize and carry the
printed sheet face up from the impression-cylinder to the delivery-tapes pending a
partial revolution of the impression-cylinder; substantially as described.
2. In a multicolor press adapted for printing sheets; consisting of two form-
cylinders of equal size covered with forms and driven in the same direction; in
combination and in operative contact with an impression-cylinder having an
impression-surface and gap, together equal in length to a form and gap-space on
the form-cylinder, and adjusted angularly, to receive upon the leading edge of the
impression-surface the leading edges of the several forms, first from one form-
cylinder and then from the other in alternating sequence; substantially as
described.
3. In a multicolor press for printing sheets, two form-cylinders of equal size
provided and covered each with one or more forms separated by the necessary
gaps; in combination and in operative contact with an impression-cylinder having
its entire periphery occupied by an impression-surface and a gap containing
grippers therefor, and arranged to make one revolution for each form on one of the
form-cylinders only, pending the printing of all the colors by the two form-cylinders
and the forms thereon, and the delivery of the sheet bearing said impressions from
the press; substantially as described.
4. A multicolor printing press for printing sheets, consisting of two form-
cylinders each of size sufficient to carry half the number of forms to be printed;
an impression-cylinder having its entire periphery occupied by an impression-
surface and a gap containing grippers, and arranged to make one revolution for
each form on one of the form-cylinders pending the complete printing and delivery
of a sheet, with inking apparatus for each of the forms, and means for elevating
and depressing said apparatus to ink or avoid any particular form as it passes ;.
substantially as described.
Dated this 8th day of May 1894.
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.