Improvements in Multicolor Printing Presses.
Year: 1894

page_text: Date of Application, 8th May, 1894-Accepted, 9th June, 1894
COMPLETE SPECIFICATION.
[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 this 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 each with an equal number of form-supporting surfaces and, in addition,
with an empty depressed space of like size. 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 on 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, after which, and pending the passage of the blank spaces the
finished sheet is delivered.
In the diagrammatic drawing which forms part of this Specification, Fig. 1, shows
the press I have invented, adapted for the production of colored work consisting of
four superimposed impressions. In this drawing 10 is the impression-cylinder;
12 and 14 are form-cylinders, with provision made by two form-supports on each
marked 16, for the forms numbered No. 1, No. 2, No. 3, and No. 4, near their
leading edges. In addition to these supports the spaces 18 on one cylinder between
the forms No. 2 and No. 4, are left, for reasons to be hereinafter explained. The
two adjacent forms on each form-cylinder are also separated by gaps, corresponding
in length to that on the impression-cylinder, and, as will be readily understood by
the drawing, the spaces 18 and 20 are themselves made up of two such gap-spaces
and a space equal to the length of a form. The impression-cylinder has a gap and
grippers 22 which close upon the blank sheet of paper fed from the feed-board 24
and hold it until all the colors are printed and the leading edge has reached the
stripping fingers at 26, when the grippers 22, by means of cam aljustments (which
are well understood and not shown in the drawings), are thrown open, and the
printed sheet passes from the impression-cylinder to the delivery tapes. 28, and from
them, as is usual, to a suitable table or other receptacle, not shown. The diameter
of the impression-cylinder irrespective of any number of forms which may be upon
each of the form-cylinders, is related definitely to that of each of the latter as one
is to one and that number added. Thus, if each form-cylinder, as in the drawing,
he provided with form-supports for two forms, the diameter of each will be
three times that of the impression-cylinder. And, as both form-cylinders and the
impression-cylinder are geared together the latter must, in the case of the press
shown, make three full revolutions to,accomplish the seizing, printing, and delivering
of one sheet, while the former are making but one revolution each. Were this a

page_text: six-color press there would be three forms on one form-cylinder, and both the latter
would then be four times as much in diameter as the impression-cylinder, which
would then make four turns before a sheet could be printed and discharged from
the press. Or, were it a two-color, two revolutions of the impression-cylinder
would be required for every sheet.
The relative angular position of the two form-cylinders in relation to the gap in
the impression-cylinder, is such, that when the leading edge of the sheet meets
the leading edge of the first form on 12 (which is marked at that place No. 1), the
printing of the first color in the series begins. This is the moment shown in the
drawing, the sheet, indicated by a heavy line, being partly on the packed surface
of the impression-cylinder and still partly on the feed-board. After having
continued its revolution for a short distance the impression-cylinder brings the
same edge to the leading edge of form No. 2 on 14, at the point of contact of
the two cylinders, the distance it has had to travel, measured on the form-cylinder,
being the same as that travelled by the gripper in moving from one point of
contact to the other, measured on the impression-cylinder. Then the sheet with
the second color partly printed goes on to form No. 3 on 12, and after that to
form No. 4 on 14. Before the last is quite printed the grippers are thrown open
and the curved fingers 26 take the edge of the sheet and guide it to the tapes 28.
The grippers have now advanced in their third revolution and as they complete it
and again pass under the end of the feed-board 24 they close upon another sheet
and immediately carry it down to the initial position shown in Fig. 1. If this
sequence of printings is followed it will be seen that the spaces 18 and 20 both pass
the impression-cylinder when there is no paper upon it and while the delivery
of the sheet is taking place; and said spaces are hence called "delivery-spaces
for their function is to secure the blanket or packing on the impression-
cylinder from contact pending the delivery of a printed sheet and the feeding of
a new one.
It is evident therefore, that in this multicolor press the printing takes place
alternately on each form-cylinder until the forms are exhausted, and then after
the passage of the delivery spaces and the delivery of the sheet the same sequence
is repeated.
As in the drawing, this machine may be driven through the pinion 30 meshing
into both cylinders. The inking of the four forms is accomplished by the several
sets of inking apparatus 31, 32, 33, and 34, only one of which, 33 is engaged in
inking at the time chosen for the drawing. Forms Nos. 1 and 2 have been inked
and No. 4 is to be inked; all the form-rollers except those for form 3 having been
lifted off their respective forms in any one of the usual well known ways, ready to
drop upon them again as the work proceeds. The forms required for a press of this
sort must of course be curved to conform with the form-supports on which they are
to rest. This may be accomplished by using stereotype and electrotype curved
plates or flexible metal plates bent over the supports and held down by well known
devices.
The cams for opening the grippers on the impression-cylinder, in this case after
every third revolution, and closing them at the proper time on the new sheet, have
not been shown as they are thoroughly understood and common in a great variety
of presses.
The principle involved in my invention makes it desirable to put an equal number
of forms on each form-cylinder, so that provision therefor is always made, but
there is obviously nothing to prevent the printing of an odd number of forms,
except that one of the form-supports would then be empty and would escape both
the form-rollers and the paper on the impression-cylinder, from which it follows
that the time required for the passage of the empty support would then be lost, the
rate of production being the same as if the total number of colors was even, that is,
one more than the odd number actually printed in the supposed case, which would
ensure a large saving.
The productiveness of this press is necessarily great, as; compared with other

page_text: known presses. The facilities also, for underlaying and otherwise getting ready in
the arrangement shown, are obvious; while the total bulk is not excessive. I wish
it however understood that I do not limit myself to the precise arrangement shown,
nor to any special way of actuating the moving parts, so long as the underlying
principle is maintained.
In this Specification, when reference is made to the "length" of a form, or form-
support, or impression-surface, or 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.
Having now particularly described and ascertained the nature of the said
invention and in what manner the saine 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 grippers, in combination and in operative contact with two form-
cylinders equal to each other in size and adapted to carry an equal number of
formis, each form-cylinder being related in diameter to the diameter of the
impression-cylinder as half the whole number of forms plus one is to one ;
substantially as described.
2. A multicolor printing press consisting of an impression-cylinder provided with
grippers, in operative relation with two form-cylinders bearing form-supports each
of length equal to the circumference of the impression-cylinder less its gap, and in
addition a depressed delivery-space of like length on each form-cylinder, both
delivery-spaces being adjusted angularly to pass the impression-cylinder when the
same is delivering its sheet; substantially as described.
3. In a multicolor printing machine adapted for printing sheets, consisting of two
form-cylinders of equal size, each bearing forms and a depressed delivery-space,
and driven in the same direction; in combination and operative contact with an
impression-cylinder having its entire periphery occupied by an impression-surface
and gap, and corresponding in size to the forms and gap-spaces upon the form-
cylinders and also to the delivery-space and gap-space upon each of the same, and
adjusted angularly to receive upon the leading edge of the impression-surface the
leading edges of the said forms, first from one form-cylinder and then from
the other, in alternating sequence; substantially as described.
4. In a multicolor printing press for printing sheets, two form-cylinders of equal
size provided with one or more forms and a depressed delivery-space on each; in
combination and in operative contact with an impression-cylinder provided with an
impression-surface and with grippers therefor, and arranged to make one revolution
for each form on one of the form-clinders, pending the several printings, and
one besides for the delivery-spaces on both, pending the delivery of the sheet ;
substantially as described.
5. A multicolor printing press consisting of an impression-cylinder in operative
relation with two form-cylinders of equal size, each having forms of length equal to
the packed portion of the impression-cylinder; and in addition a depressed
delivery-space of like length on each form-cylinder, together 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.