Year: 1887

page_text: Date of Application, 26th July, 1887.
Specification Accepted, 26th Aug., 1887.
[Communicated from abroad by DWIGHT SEXTON CLARK, Printer, of Cambridge, in
the County of Middlesex, and WILLiam Charles WeNDTÉ, Mechanical Engineer,
of Lancaster, in the County of Worcester, both in the State of Massachusetts,
United States of America.]
I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents, 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 presses in which a sheet
of paper fed to the same, receives impressions in two or more colors upon its face
before delivery, said printings all contributing to the formation of a single design,
and its object is to provide a machine of simple construction, securing an accurate
register, and a rapid rate of production.
In the drawings forming part of this specification-
Fig. 1 represents a cross section of the cylinders used in a machine for printing
four colors.
Figs. 2 and 3 are similar views of modified constructions of the press.
Fig. 4 is also a similar view showing a press in which six colors are printed, with
other modifications.
Fig. 5 is a side, and Fig. 6 an end elevation of a form cylinder.
These drawings are diagrammatic in character, the general shape of the several
parts which together form the press, being for the most part well known and
understood, and all unessential details, such as the frame of the press, the bearings for
the cylinders, most of the gearing and many connecting pieces of mechanism are
omitted, as they tend to obscure the relations of the more important parts.
The large cylinder a is an impression cylinder around which the form cylinders b,
are arranged at suitable intervals. Each of the latter is provided with an inking
apparatus c which is represented as consisting of the simplest elements, namely, of an
ink fountain, ductor roll, rider, and two form rollers, though in practice a more
elaborate and efficient inking system would be required in most cases. Each form
cylinder has attached to and covering part of its surface, a cylindrical form adapted
for the printing of one of the colors which go to make up the chromatic design, the
uncovered portion being depressed so as to form a gap, in a way very commonly met
with in large presses. This depressed part of each form cylinder is chiefly used to
facilitate the adjustment and making fast of the forms, which operation need not be
more fully referred to in this specification. The large cylinder a, has upon its periphery

page_text: a number of impression surfaces d (which term will be adhered to throughout for
convenience in description), and it is also provided with a like number of gaps in
which the grippers e are located. These gaps also contain the reel rod &c., used for
holding the packing and tympan sheets which cover the impression surfaces d, but
they are not shown as they are in no wise essential to a proper understanding of our
invention. In this press the large cylinder is driven by a gear upon its edge and all
the small cylinders are driven by said gear; the same being omitted in the drawings,
except in Figs. 5 and 6 in which the gear upon a form cylinder appears. The diameter
of the impression cylinder in this press should be some multiple of that of the form
cylinders which are all precisely alike, so that any point upon the surface of a
form cylinder invariably comes in contact with the same points upon the impression
cylinder. Furthermore, the form cylinders are so arranged about the circumference
of the large cylinder that the gaps in each correspond, and as a consequence, each
form will roll over an impression surface as it passes.
In the drawings the distances between the centres of the form cylinders are generally
about equal, and to have them so may often be found convenient in practice, but it is
by no means necessary, as the coincidence of the forms with the impression surfaces
depends upon the angular position of given points of contact upon their surfaces
and not upon their disposition about the circumference of the impression cylinder,
means for the adjustment of which will be described subsequently.
From the foregoing description of our invention it will be seen that when a number
of sheets of paper are fed successively to each impression surface from feed board /,
as they pass the same, each sheet being taken hold of by the grippers e, in the well
known way, they will all have received impressions from all the forms when they
reach the end of the series of form cylinders, each having had printed upon it then,
the finished chromatic design.
Our invention further consists in mechanical devices by which the speed may be
increased, and the quality of the work done by it raised to the highest excellence.
To accomplish these results it is necessary to supply the machine with sheets of paper
at a much faster rate than can be accomplished by a feeder of average capacity, a
necessity which is essentially dependent on the peculiarities and perfections of our
press. When, as provided for in Fig. 1, a single feeder is employed to lay the sheets
upon the feed board f, for seizure by every set of grippers on the impression cylinder,
it is evident that the time at his disposal after the tail of the preceding sheet has left
the feed board when he can reach the stops in front, will only be that required for the
passage of the gap.
If about three seconds is occupied in laying a sheet, a rapidity which is not often
reached, it will be readily understood that the surface speed of the cylinders, or, in
other words, the actual printing speed, is exceedingly slow. It is a well established
fact that good printing is not possible when a press runs much below the normal
speed, which is about that reached in reciprocating presses by the best makers. In
these last named machines where the interval between the sheets fed to the impression
cylinder is relatively long, the actual time in which the printing is done is short, being
but a fraction of that required for a perfect revolution of the press, and the quality
of such work from a typographic form, would be found to undergo deterioration were
such a press run at a rate of speed no faster than that of the possible printing speed
of this chromatic press fed by one person. In the press we have invented, the
utilization of a higher speed than is possible with ordinary feeding, as in Fig. 1, may
be accomplished in several novel ways. In Fig. 2 the increase of surface speed is
made feasible by supplementing the ordinary feedboard with the additional board o,
placed further forward on the frame of the press. On this board the pile of unprinted
sheets is put. Such an arrangement admits of two feeders working at opposite sides
at the same time. Taking sheets alternately from the pile at o, each feeder places his
sheet on the board f, to the back stop at p, and holds it down with his fingers till the
grippers seize it, at that moment without waiting for the sheet to leave the board,
the other feeder lays his sheet in like manner to the stop p, and holds it; the first
taking a fresh sheet from the pile while he does so. In this way the speed of the

page_text: press may be more than doubled with safety, as neither feeder has to wait for the sheet
to leave the board. Nor do the feeders in this novel arrangement interfere with
each other, because each takes hold of the sheet by the tail and carries it to the back
stop p. which they could not do so well if the pile of sheets was on the one feed board
as in Fig. 1. This method of rapid feeding is plainly applicable to all presses printing
sheets, when room can be made for the board o.
In Fig. 3 another analagous method is shown which makes an increased speed
possible. In this case the feeding is done as in Fig. 1, but two independent feed
boards are used, marked f¹, and f, respectively. At each board the feeder places his
sheet in the usual way to front stops, but alternate grippers only on the impression
cylinder, close upon these presented sheets and carry them to the impression surfaces,
so that each feeder has the time required for two sheets in which to place one.
these circumstances our press can be run much faster than when a single feed board
is used, because in place of having only the time in which one gap passes he has the
time of two gaps and a sheet besides after the tail of the preceding sheet has left the
board.
Under
In Fig. 4 three feed boards are employed and the feeding is done from below for
reasons to be presently stated. These feed boards are marked, and 3, respectively,
they are suitably formed and adapted to the positions in which they are placed, and
are provided with the usual hinged flaps, which by well known devices are raised into
place at the moment the sheet is caught by the set of grippers that is to take it. In
Fig. 3 the feed boards are separated from each other by exactly the length of an
impression surface and gap, in consequence of which the two sheets are fed together
and seized at the same instant, though printed and delivered seriatim afterwards. But
such a disposition of the feed boards is by no means essential, and is not followed in
Fig. 4, it being quite immaterial where they are placed, provided they present the
sheets properly to the impression cylinder in advance of the form cylinders. All
that is necessary when the feed boards are put at odd and irregular intervals, is that
the gripper marked e¹, should close when it reaches the feed board f1, that marked e²,
when it reaches, and in like manner e³, as it passes/3, and so on; each cam or stud
in the press frame adjacent to each feed board, closing every third gripper as it
comes into position, and escaping the two intervening, in a manner analagous to the
periodic engagement of the stud and gripper mechanism in the Boynton and many
other presses. Each feeder for the press shown in Fig. 4, has the interval of time
occupied by the passage of three gaps and two sheets in which to lay his own sheet.
In delivering from the press we have invented we employ known methods which
are well understood. So long as a slow speed is admissible the delivery cylinder 7,
and fly r, may be employed in the well known way, as shown in Figs. 1, 2 and 3, but
as a rule we prefer in most cases the delivery mechanism shown in Fig. 4, which
consists of the fingers g, which catch the leading edge of the sheet at the moment the
gripper is thrown open, and convey it face up to the endless tapes i running con-
tinuously in the direction of the arrow. From these tapes it falls into a sloping tray,
or is removed from their surface by hand. Of course such tapes can be carried to any
desired distance from the press. To make sure that the leading edge of the sheet shall
rise over the fingers at g, the tube k, may be employed. This tube is connected with
a blower or other air compressor of some suitable kind; it is perforated with a row of
holes directed towards the approaching sheet, from which a current or blast of air is
forced in such a way as to make sure that the leading edge of the printed sheet shall
rise over the fingers. This use of a blast of air to lift the sheet from the impression
surface is old, and is by no means the only device that can be employed, as there are
several forms of shoo-fly well known to press builders, which can be substituted for it
with perfect success.
The method of underfeeding is adopted in the case shown in Fig. 4, with a view to
the delivery of the sheet face up, by means of the fingers g, and tapes i, from the
upper part of the impression cylinder. The peculiar curved construction of two of the
feed boards in this case, and also in Fig. 3, is designed to present the leading edge
tangentially for seizure by the grippers.

page_text: In the press we have invented the form cylinders b, are so placed that the gaps in
them correspond to those containing the grippers in the impression cylinder, so that
the leading edge of the sheet upon the latter meets the leading edge of the form upon
the former. But in placing the forms and securing them to the cylinders b, it is
difficult to put them so truly in position, circumferentially, as to obtain a perfectly
exact register. This we accomplish by letting the gears 7, of the form cylinders b
(shown in Figs. 5 and 6) turn freely on their shafts within small angular distances,
and then clamping them fast after the adjustment for circumferential register has
been accurately made. In these figures the bolts used for clamping are marked with
the letter m, the function of which will be understood without further explanation.
From the foregoing it will be seen, that the press we have invented is well adapted
for the rapid production of chromatic work, which is essentially due to the fact that
all the forms, irrespective of the number of colors, are printing at the same time. In
addition to this, we have by the subdivision of the face of the impression cylinder
into a number of impression surfaces, succeeded in presenting for the several colored
impressions, a series of sheets with very little lost space between them, which can be
fed with great rapidity and without the delays due to reciprocating machinery, or the
successive printing of one color after another on the same sheet but at different times.
It will also be readily understood, that while the length of an impression surface
determines that of the longest sheet that the press can print, any shorter sheet can be
easily dealt with as in other presses.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, as communicated to me by my
foreign correspondents, I declare that what I claim is :—
1. A chromatic printing press, consisting essentially of an impression cylinder
having around its periphery two or more distinct impression surfaces, with gaps
between the successive surfaces for the reception of grippers, and two or more form
cylinders in operative relation to and in register with the impression surfaces, sub-
stantially as described.
2. In a chromatic printing press, the combination of two or more form cylinders,
with an impression cylinder having around its periphery two or more distinct
impression surfaces with adjoining gaps for the reception of suitable grippers, the
length of each impression surface with its adjoining gap being equal to the cir-
cumference of each form cylinder, substantially as described.
3. In a chromatic printing press, the combination of an impression cylinder having
its periphery divided into a number of equal parts, consisting each of a distinct
impression surface with adjoining gap for the reception of suitable grippers; with
a number of form cylinders in operative relation to and in register with the impression
surfaces, substantially as described.
4. A chromatic printing press consisting of an impression cylinder, having around
its periphery two or more distinct impression surfaces with adjoining gaps for the
reception of suitable grippers; two or more form cylinders in operative relation to and
in register with the impression surfaces, and feeding and delivery devices, substantially
as described.
5. In a chromatic printing press, the combination of an impression cylinder having
around its circumference a number of distinct impression surfaces with adjoining gaps
and a set of grippers in each gap; with two or more feed boards, each in simultaneous
operative relation to two or more sets of the aforesaid grippers, substantially as set
forth.