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Патент USA US2121309

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J’ 21, 1938.
Filed March 28, 1955
2 Sheets-Sheet 1
Z2 ;
June 21, ‘1938. I
“ 2,121,309
Wm I
ME .
m q‘H T 3 w
3 TnO
. B?
Patented June 21, 1938
, 2,121,309v
aoramr ramrmo PRESS
Bruce. Wale, San Francisco, Calii'., assignor to
Standard Process Corporation, Chicago, 11]., a
‘ corporation of Delaware
Application March 28, 1935, Serial No. 13,461
7 Claims.
(Cl. 101-378) ‘
This .invention relates, to rotary printing
presses of that class which print direct to paper
from the raised portion of type or its equivalent
or from a printing plate whose printing surface
is in relief. Such presses are usually known
as typographic presses and the printing plates
are frequently referred to as' typographic print
ing plates.
Heretofore, the printing plates as employed in
10 these presses have been quite thick and rigid
(the thickness varying from 1*," to $4,”), being
preformed to a de?nite and predetermined shape
to ?t the printing cylinders and capable of
maintaining such shape by their own strength
15 or self-supporting character. As thus made, the
plates are securedv to the cylinders merely by
clamping them down. The different kinds of
plates and the different ways they are produced
are too well known to merit detailed discussion,
20 although the most common are stereotypes and
The use of such thick and rigid printing plates
in order to prevent the non-printing areas from
being inked or impressed. On a single plate this
depth of relief will range between 1,64"- and 952"
in varying amounts.
A still further di?iculty arises in feeding the 5
paper through the press. Due to the great depth
of relief and the lack of trueness or concentricity
of the printing surface of the plate, it is neces
sary to keep the paper under positive control
during the entire period of impression. On such 10
presses this is accomplished by paper tension and
pulling rollers acting before and after printing
and involving in addition, a considerable arc of
“wrap" of the paper around the _ impression
cylinder. On sheet-fed presses. grippers are em
ployed to hold and pull the sheet until printing
has been entirely accomplished. Because of this
necessity, the true and natural ?at surface of
the paper is distorted, and the paper is obliged
to accept the imprint while its ?bers and sur- 20
face are in a strained and curved condition.
This, incidentally, adds to the necessity of a
is costly, troublesome and time consuming, not ' heavy squeeze‘to secure satisfactory printing.
only from the standpoint of‘forming the original
While this old practice of printing in typo
25 plates, but also because of certain re?nements
graphic presses has prevailed for many years and 25
which must be observed in ?nishing .the plates
before they can be applied to the cylinders or
printed from. Thus, the plates (owing to the
process followed in reproducing the original type
30 form) invariably present uneven or non-con
' centric printing surfaces, and it is necessary to
correct these irregularities, as by “underlaying”
the plates where low spots occur, and “shaving
down” the plates where high spots occur. And,
35 in some instances,‘ as for solid areas, an addi
tional “underlay” of .010" more or less is re
quired to secure satisfactory inking and impres
sion of that particular solid area.
Notwithstanding these and other. manipula_
40 tions, (sometimes referred to as “make ready”),
it is practically impossible to produce a true and
accurate printing surface, and hence the adjust
ment of the inking rollers and of the impression
cylinder must be such as to compensate for any
45 irregularities remaining in the curved printing
plate. For example, the inking rollers are usually
adjusted to have a %" “streak” or more in order
to reach all parts of the printing surface, and the
impression cylinder must likewise be adjusted
50 for a rather heavy “squeeze” in order to force
the paper into contact with the low as well as
the high spots of the printing surface. Both of
these conditions demand that the depth of relief
must be considerable depending upon the char
acter and related locations of the printing areas,
in fact is in common use today, being perforce
accepted as satisfactory for good printing, the
objections referred to are inherent in the prac
tice and the perfection acquired in printing is
‘dependent essentially upon the skill and care 30
exercised in preparing the printing plates and
in the make ready.
The present invention is intended to obviate or
minimize the foregoing objections in typographic
presses and contemplates a novel form of print- 35
fng plate which can be applied directly to its
supporting cylinder and used at once for printing -
without the necessity of any‘further manipula-,-_
tion and without the need for any particular
skill. It is also within the contemplation of the 40
invention to provide a printing plate which may
be produced at small cost and without di?iculty
and still be capable of printing with the utmost
In the practice of my invention (speaking of a 45
preferred embodiment), I employ a ?at zinc or
copper plate of an initial uniform thickness of
the order of .006" to .008"; I make from it a
zinc or copper etching, andfin the etching step I
remove the metal to a depth of .002” to .004". 50
This method (etching) of producing a plate gives
a uniform depth of relief in the entire extent of
the plate, hence the non-printing surface will be
at a uniform and constant distance, below the
printing surface on any given plate, regardless 55
of subject. I am careful so to control the etch
contact therewtih and this irrespective of the
ing step that the plate will not be eaten‘ through
where ?aws appear in the metal but I have found
nature or extent of the printing surface, it being
remembered that the plate is of such thinness
and ?exibility as to become a perfect cylinder
when mounted under tension on a truly cylindri
cal supporting member.
that even if, in consequence of accident or inat
tention. the plate be eaten through in such
places, the desired result may still be gained.
Considering these dimensions, it is readily appar
ent that so thin a sheet of metal is in fact
The etched plate is then applied
10 directly to a truly cylindrical supporting mem
ber or carrier by means mounted on the carrier
and which are operative to draw the plate taut
about the face of the carrier with su?icient ten
sion to bend the plate to and maintain it in true
15 cylindrical shape for printing, the carrier with
the plate as thus mounted'thereon becoming of
‘course the printing cylinder. Nothing further is
required, and the printing operation may be car
ried on as usual.
In my commercial development, I have printed
letterheads and billheads from such plates when
mounted on printing cylinders 11" in circumfer
ence and even as little as 8.50" in circumference,
this latter circumference corresponding to a di
I mention the type of printing
25 ameter of 2.70".
and the small size of the printing cylinder to
emphasize the radical change brought into the
art by my invention, it being obvious that the
printing of letterheads and billheads (which
30 usually present an extensive blank or white
area), as well as the small size of printing roller,
aggravate the conditions which must be met to
produce good printing. Nevertheless, the print
ing produced under the conditions stated was
35, substantially perfect and presented no particular
It will be seen, therefore, that my novel print
ing plate, while having its printing portions of
substantially greater thickness than that of its
40 non-printing portions, relatively speaking, is so
thin and ?exible in its thicker printing portions,
yet possesses such tensile strength in its thinner
non-printing portions, that the plate, when ap
plied under tension to a truly cylindrical support
45, ing member, will present a true cylindrical print
ing surface. According to the dimensions given
above, the depth of etching does not exceed one
half the original thickness of the plate (being in
fact just one-half in the case of the .008", plate),
50 it being found that under such conditions the
stresses set up in the thicker printing portions
are no greater than those setup in the thinner
non-printing portions and that as a consequence
the plate when applied under tension to its sup55 porting cylinder will be given a true cylindrical
shape, its smooth back conforming exactly to the
‘ smooth rigid surfaceof the cylinder, its printing
face being drawn into corresponding cylindrical
shape, and the non-printing surface being like
60 wise given true cylindrical shape so as not to
destroy the uniform depth of relief.
In the use of my improved plate, as thus
mounted on its supporting cylinder, the inking
roller is set in non-contacting relation to the
The invention is particularly suited for com
mercial work, such as letterheads, billheads, ruled
forms, and other printed matter commonly
ordered in large quantities. For such work, a 10
small printing press embodying my improvements
will answer the needs of a job-printing estab
lishment which is required to turn out such work
with speed and economy. Because of their ex
treme thinness and ?exibility, the plates when
removed from the supporting cylinder may be
laid out ?at and stored away in that condition,
thereby contributing to further economies in
storage or ?ling, etc.
While as just stated the invention is particu 20
larly suited for letterhead and similar commer
cial work requiring the use of a small printing
cylinder, it should be understood that the in
vention in its broader phases embraces the com
plete scope of the typographic printing art in 26
which relief surfaces are used for printing di
rect to paper. It is also worthy of note that
the invention, in the production of the improved
plate, permits the use of the customary etching
process which eliminates all possibility of per 30
petuating any irregularities or unevenness in the
original typographic surface to be reproduced.
In fact, the invention provides for the ?rst time
an etched relief plate capable of being mounted
directly on the printing cylinder of a rotary press. 35
In the usual production of zinc etchings, a plate
of a thickness of 11;”, or more, is employed. The
etching step involves the removal of the metal
to a depth of the order of .05”. Additionally,
over broader spaces between the lines of the 40
etching, the metal is routed out to greater depth.
This is done in order to prevent the surface
of the plate in these cut-away portions from
coming into contact with the inking rollers or
with the paper. The plate when prepared is 45
mounted on a plane-surfaced wooden block. It
is rigid, and, in the printing, surface-to-surface
contact under pressure is made between paper
and plate. It is obvious that such a plate is in
capable of being used directly on the printing 50
cylinder of a rotary press, ?rst, because the
thickness of the printing portions of the plate is
too great to permit them to be given a true
cylindrical shape by applying the plate under
tension to the printing cylinder, and second, be 55
cause the thickness of the non-printing por
tions is so‘ small in relation to the original thick
ness of the plate that said non-printing por
tions would not possess sufficient tensile strength
to bend the thicker printing portions into true
cylindrical shape when the plate is applied under
tension to a cylindrical supporting surface.
Moreover, the depth of relief of the printing sur
face of such a plate is altogether too great to
65 plate, being spaced from its printing surface at
a distance corresponding to the desired thickness
of the ink ?lm to be deposited thereon, and the
enable the printing and impression cylinders to
advance the material through them solely by
contact therewith. Indeed, the depth of relief
impression cylinder is also set in non-contacting
relation to the plate, being spaced from its print
is so great that the use of tractive devices would
70 ing surface at a distance slightly less than the
thickness of the material to be printed upon.
Owing to the shallow depth of relief of the print
ing plate, the printing and impression cylinders
are enabled to advance the material through the
75 pass formed by and between them solely by their
be required to advance the material through the
.pass formed by the printing and impression 70
cylinders in order to nullify or render ineffec
tive any tendency of the cylinders to advance
the material, such being the condition which
actually prevails in typographic presses employ
ing stereotypes or electrotypes.
In the ‘accompanying drawing:
. Fig. 1 is a, sectional view, largely diagram ‘with the'paper, it being noted from Fig. 1 that
the cylinders are set‘in non-contacting relation,
matic, of a typographic press embodying my in
withthe surface of the impression roller spaced
Fig. 2 is a plan view of the improved printing from the printing surface of the printing roller
at a distance slightly less than the thickness of
Fig. 3is alongitudinal section on an enlargedv the paper. The printing areas and the non
scale taken through the printing plate of Fig. 2; printlng areas alike (regardless of the ‘irregular
plate, broken away at the center; I
Fig. 4 is an ‘enlarged cross section taken
10 through a portion of the printing cylinder and
showing one form of the tensioning means em
ployed for applying the plate to the cylinder;
Fig. 5 is a ‘view similar to Fig. 4, but showing
another form of plate tensioning means;
Fig. 6 is a section taken longitudinally through
the tensioning means of Fig. 5;
Fig.‘ 7 is an. enlarged cross section ‘taken
through a portion of the impression cylinder
ity. or unevenness of the form’ or pattern)‘ ad
vance the paper. In extreme cases, the printing‘
plate I may be formed in relief with marginal 10
bands 2“, constituting no part‘ of the printing
image, to aid the printing and impression cylin
ders in affecting the advance of the paper. '
The paper may consist of detached sheets, one
entering the ‘roll-pass with each rotation of‘the 15
printing roller 8 ;- or, as commonly‘ will be the
case, the paper may consist of a continuous web.
and showing the tensioning means employed 'Upon the continuous web a sequence of impres
20 for applying the tympan paper to the cylinder; sions ‘will with the successive rotations of the
Fig. 8 is a plan view of a printing plate used printing roller be printed; and, if the paper he 2o,
a. continuous web, rotary shears may be driven
for tabular work, the plate being broken away
both longitudinally and transversely; and
Fig. 9 is a perspective view of a section of the
25 plate shown in Fig. ,8.
Referring to Figs. 2 and 3, a plate I, of the;
initially small thickness already indicated, is sub
jected to the usual operations of making a zinc
etching, with the quali?cation, ‘however, that
30 the etching‘step is shortened. Ordinarily the
metal will be eaten away to a depth not greater
than .004”.
In addition to the characters 2,
the margins 3 at the ends of the plate are pro
tected and left of undiminished thickness.
in synchronism with the press, to cut the printed
web to a succession of accurately measured
In my copending application Serial No. 726,875,
?led May 22, 1934, I have disclosed special de 25
vices for feeding paper to the press in both sheet
form and in web form and these devices will be
found to be particularly useful in a press
equipped with my improved printing plate.
Associated with the printing roller or cylinder
8 are suitable inking means, including in this
case the inking roller l5. This roller, as will be
noted from Fig. 1, is set in non-contacting rela
35 Across these end portions, however, properly ‘ tion to the printing'surface of plate I, being
spaced lines 4 are etched. In these end portions,
‘too, are formed ori?ces 5. When the plate has spaced therefrom at a distance corresponding
the desired thickness of the ink ?lm I5a to be
been prepared in the flat, the margins are ,bent to
deposited upon the printing surface. As the
along the lines 4, to form the terminal channels
40 6 and ‘I.
The printing roller or cylinder 8, ordinarily
of steel, of a size to which the plate is accurately
formed, is provided with a longitudinally-ex
tending groove 9. The plate is applied to the
45 roller with its marginal channels 6 and 1 nested
one within the other, andthe nested channels
within the groove 9. A clamping bar I0 is then
set within the ‘inner channel and the whole is
secured by screws II that penetrate the bar l0,
pass throughthe ori?ces 5 in the plate, and
enter, screw-holes in the body of the roller. All
is accurately proportioned, so that the plate is
drawn taut upon the face of the roller and ?rm
ly secured. The securing means are such that
55 plates are readily applicable to and removable
from the roller, and a minimum space, circum
ferentially, is required for anchorage. It follows
inking roller is thus arranged, no ink, will be
deposited upon the non-printing surfaces of the
plate I and there will be no smudging of the 40
paper during the printing impression even
though the paper at times will touch such non
printing surfaces as it is advanced by the con
tact therewith of the printing and impression
Figs. 5 and 6 show a modi?ed form of ten
sioning means for applying the printing plate,
here designated I“, to the printing cylinder‘, 8.
In this instance, the terminal unetched portions
6“ and 18 of the plate do not nest one within
the other, as in Fig. 4, but are clamped in end to
end relation between two bars 20 and 2| by
means of short screws 22 passing through plain
openings formed in theouter bar 20 and screwed
into threaded openings formed in the inner bar 55
2|, the plate l8L being formed with. notches in
its opposed ends to straddle the screws. Once
,the plate is clamped between-the two bars 20
and this, as I have indicated, is advantageous. _ and 2| they'are‘then drawn downwardly or in
Referring to Fig. 1 the roller 8 with a plate wardly in the parallel sided groove 9 by long
secured upon its surface is brought into usual
association in the printing press. Cooperating screws 23 which pass through plain openings
with it is an impression roller or cylinder l2, formed in both bars and are screwed into
threaded openings 24 formed in the bottom wall
which is a smooth. steel roll of like diameter of the, groove 9. In applying the‘printing plate
faced with a tympan sheet iii‘ of paper (or it
to the printing roller therefore, according to
might‘be a thin layer of semi-hard rubber); this embodiment, it is merely necessary ?rst to
‘ and between these two rollers the paper P to be
clamp the ends of the plate between the bars
printed is advanced. Ordinarily the rollers or
20 and 2| in the manner just described and then
cylinders 8 and I2'are positively driven at equal tocdraw
the two bars as a unit down into the 70
surface speeds, and the paper is caused to ad
groove’ 9 by turning the screws 23, this being
vance at uniform speed with them as they rotate. done progressively and uniformly until'the nec
- In the present ‘instance, such advance of the
essary ‘tension is applied to the plate to shape
paper is effected solely by the mutual coopera
upon the the supporting surface of the print
‘is tion of the two cylinders or by their contact it
ing cylinder. It will be observed that the bar 20 76
that for a given area of printing surface the
size of the roller may be reduced to a minimum;
cured to the cylinder by drawing means thereon
which exert sufficient tension on the plate to
of the bar 20, and the sides of the groove 9 to _ give it its proper printing shape,—the plate in
accommodate the thick terminal portions of the fact being incapable of being brought to print
is slightly narrower than the bar‘ 2| so-as to
leave enough space'between the opposite sides
plate, although the space provided isintended to
make a tight fit between the contacting surfaces‘
in, Order that the tension originally applied to
,_ the plate will not be relaxed.
method of production, invariably present untrue
Fig. 7 shows a convenient method of applying
the tympan paper IE to the impression cylinder
l2. ‘Here it will be observed that the ends of
plate, because of its thinness and method of 10
production, always presents a true cylindrical
the tympan sheet are folded over reinforcing
wires 11 to produce what in effect are two beaded
edges.._ These beaded edges are then placed in
longitudinal grooves formed in the side walls of
a clamping bar ‘I8, which latter is adapted to
be drawn downwardly by screws 19 into a par
allel 'sided groove I 8' formed in the impression
cylinder in a zone corresponding to that occupied
by the groove 9 in the printing cylinder 8. In
using a thin printing plate, such as herein de
scribed, one thickness of tympan paper will
ordinarily su?lce, although care should be taken
to see to it that the paper is always drawn taut
upon the surface of the cylinder.
In Figs. 8 and 9, there is shown a printing
plate Ib which gives a better illustration of the
kind of plate that would be used for commercial
work, the plate shown being a typical example
of one intended for printing tabular work involv
ing the use of type matter as well as rule matter.
In this example, it will be noted that practically
the whole area of the plate is occupied by the
printing image, although the spacing of the dif
35 ferent parts of the image is irregular and non
uniform except for the horizontal lines which
are more'or less uniformly spaced in this par
ticular example. In the use of a plate such as
I“, there would never be need for the use of
40 separate marginal bands such as bands 2‘
shown in Fig. 2. It willrhave been understood
that the printing plate I shown in Figs. 1 to 4
is intended primarily for purposes of illustra
tion, although it could actually be used in the
ing shape except when thus applied to the cyl
Prior plates, because of their thickness and
» l
‘I The subject of the zinc etching may be what
one will; and it may, as will be understood, be
applied to the plate photographically, by contact
printing or otherwise, from a'master-piece that
may itself be a print or drawing. or from an orig
inal of other form or character.
_ The term zinc etching is one that has come to
be applied by extension to an etched metal
place, even though the metal be other than
zinc. ‘I shall ‘in the ensuing claims use the
terms etching and metal to cover ‘such wider
My improved plate, when compared with prior
printing plates used in‘typographic presses, pre
sents striking and numerous dissimilarities:
Prior plates'are thick and rigid, being applied
to the printing cylinder after being preformed to
shape (stereotypes are of course cast, while elec
tro'types are'rolled or pressed to shape, usually
when heated) and capable when removed from
the cylinder of maintaining their shape by their
own strength, and self-supporting character;
whereas my plate is thin and ?exible, being made
from sheet metal by an etching process and
70 shaped directly on the cylinder, audit is incapable
when removed from the cylinder of maintaining
printing shape or any definite shape.
Prior plates are secured to the printing cylin-‘
der by clamps which act merely to hold the
II plates down in place; whereas my plate is se~
or non-concentric printing surfaces; whereas my
printing surface.
Prior plates, also because of the untrueness, of
their printing surfaces, require a great depth
of relief, as well as a non-uniform depth of 15
relief; whereas my plate, because of the true
ness of its printing surface, permits of a small
depth of relief, as well as of a uniform depth of
Prior plates, because of their great and non
uniform depth of relief, present non-printing
portionsnot nearly so thick as the printing por
tions, thereby forbidding the use of tension in
attaching the plates to the printing cylinder;
whereas my plate, because of its small and uni
form depth of relief, presents non-printing por
tions which can be made half as thick as the
printing portions, this relative thickness of the
printing and non-printing portions permitting
the plate to be shaped under tension on the 30
printing cylinder and in fact forbidding shap
ing in any other manner.
Prior plates, because ‘of the lack of trueness or
concentricity of their raised printing surfaces,
require the use of inking rollers and impression 35
cylinders which are set to rotate in overlapping
relation to the printing cylinder so as thereby
'to make a substantial or wide surface contact
with the printing surfaces, these conditions ne
cessitating a great depth .of relief of the printing 40
surfaces; whereas my plate, because of the true
ness or concentricity of its raised printing sur
face, permits the use of an inking roller and
of an impression cylinder which are set in non
contacting relation to the printing cylinder or 45
the printing surface of the plate, these condi
tions permitting a minimum depth of relief of
the printing surface.
. '
Prior plates, because of the lack of trueness
or concentricity of their raised printing sur 60
faces, as well as the great depth of relief of
these surfaces, necessitate the use of tractive
devices for advancing the paper through the
pass formed by and between the printing and
impression cylinders; whereas my plate, because 65
of the trueness and concentricity of its printing
surface, as well as the small depth of relief of
this surface, enables the printing and impres-I
sion cylinders by their own tractive effort to ad
vance the paper through the pass formed by and 60
between them.
Prior plates are costly, requiring special treat
ment or make ready after casting or shaping;
whereas my plate is relatively inexpensive, re
quiring no special treatment or make ready after 65
the etching operation.
Prior plates cannot be conveniently stored away
for repeated use because of their bulk and their
permanently curved form; whereas my plate,
because of its light ?imsy character, can be 70
used repeatedly and laid out ?at for filing away
in any standard filing cabinet like an ordinary
paper record.
Prior plates are not well suited for letterhead
and similar commercial work, being altogether 75
2,121,309 "
too costly; whereas myi plate is particularly
adapted for such work.
It will be seen therefore that my invention
represents a decided innovation in typographic
c: printing presses. The improved plate is really
unique and offers an entirely new technique
in the art of typographical printing surfaces.
I am aware that printing plates which may
render the plate freely ?exible in the thicker or
printing portions while ‘at the same timermain
taining high tensile strength .in the thinner or
non-printing portions and said tension being su?i
cient to shape both-printing and non-printing
portions of said plate to conform'accurately to'
the curvature of said carrier surface.
‘ »
2. A printing element of the~type de?ned in
be said to be thin and ?exible have been 'used _ claim 1 wherein said printing plate is etched to
10 in planographic or offset -‘ presses as well as in
obtain said uniform depth of relief of the non 10
intaglio presses, and that in some instances it printing portions at said outerface.
has been proposed to apply these plates to their
3. An element according to claim 1 wherein
supporting cylinders by means of tension. Such said plate is formed to provide a relief ‘of sum
planographic or intaglio printing plates are not cient height to print on paper passed between
intended, designed or adapted for use in a typo
said impression means and said plate, yet su?i
graphic press‘ and hence they afford no basis ciently shallow to cooperate with the non-print 15
of comparison with my improved plate which, _ ing portions of said plate to produce a de?nite
as already pointed out, has been evolved to meet advance of the paper to be printed upon irre
the special and peculiar conditions arising in a spective of the nature or extent of the printing
typographic press. A typographic printing plate
must present a relief printing surface which
can be inked by a roller and which can print
My improved plate, being a
typographic printing plate‘, does (as it must)
, direct to paper.
meet these requirements, and it has been seen
from the detailed comparison above, how radi
cally my improved plate differs from prior plates
in the same class. The idea in applying plano
‘ graphic and intaglioplates by tension to ‘their
supporting cylinders is much the same as that
followed in applying tympan sheets to impres
sion cylinders and rubber blankets to offset cyl
inders, the object in all cases being to facilitate
' the .application and removal of the cylinder
facings for renewal or substitution purposes.
While my improved plate possesses that ad
vantage also, it ‘is purely secondary, the thin
ness and ?exibility of the 'plate and its other
structural characteristics being determined solely
an from‘ the standpoint of printing and press opera
I have herein shown and described my inven
tion merely in preferred form and by way of
example, and it will be understood that many
changes and variations may be made in the form,
‘arrangement and dimensions of the parts with
out departing from the ‘spirit of the invention.
It should be understood, therefore, that I do not
limit myself to any particular form, arrange—
ment or dimensions of the parts except insofar
as such limitations are speci?ed in the appended
This application is in part a renewal and con
tinuation of an application ?led by me April 20,
1933, Serial No. 666,987, allowed April 11, 1934,
and in part a continuation of my before-men
tioned copending application Serial No. 726,875,
filed May 22, 1934.
, Having thus described my invention, what I
claim is:
1. A printing element adapted to print di
rectly upon sheet material irrespective of the
nature of the subject matter to be printed and
irrespective of the relation in area or location of
65 the ‘printing portions to the non-printing por
4. An element according to claim 1 together
with means provided within said element to draw
said plate taut uponsaid carrier to secure the
‘desired tension.
5. ‘A ‘printing element adapted to print di 25
rectly upon sheet ‘material irrespective of the
nature of the subject matter to be printed and
irrespective of the relation in area orrlocation
of the printing portions to the non-printing por
tions comprising a rigid carrier having an ac 30
curate cylindrical surface ‘and a thin ?exible
sheet metal relief printing plate drawn taut upon
the surface of said carrier by means of uniform
tension applied to said plate, said plate having
an outer face comprising printing and non
tions, the relative thicknesses of said printing and ,
non-printing portions being so proportioned as to
render the plate freely ?exible in the thicker or 40
printing portions while at the same time main
taining high tensile strength in the thinner or
non-printing portions and said tension being suf
?cient to shape both printing and non-printing
portions of saidplate to conform accurately to the
curvature of said carrier surface without lateral
distortion of the design at said printing surface
due to said tension.
6. A printing element
sisting of a cylindrical
longitudinal groove, a
away and bearing over
for a printing press con
carrier provided with a 50
plate of metal etched
an intermediate portion
printing characters in relief, and with marginal‘
end portions etched away along lines of bending,
and bent along such lines to channeled shape,
the said plate being shaped upon the face of the
carrier, its channel-shaped margins nested one
within another and both nested within the
groove of ‘the carrier, and means engaging the
nested channel-shaped margins of the plate and 60
securing the plate to the carrier.
7. The method herein described of preparing
the printing element of a printing press which
consists in forming by 'etching'upon a medial
portion of the surface of a plane sheet of metal 65
a printing character in relief, and upon marginal
tions comprising a rigid carrier having a smooth
curved surface and a thin ?exible sheet metal and portions lines of bending of diminished
relief printing plate drawn taut upon the surface thickness, bending the marginal end portions of
of said carrier by means of uniform tension ap - the sheet to channel shape, shaping the sheet
70 plied to said plate,v said plate having an outer
face comprising printing and non-printing-por
‘ tions, the latter having a uniform depth of re- ,
lief with respect to said printing portions, the
relative thicknesses ofsaid printing and non
printing portions being no proportioned as to
printing portions, the latter having a uniform
depth of relief with respect to said printing por
upon a longitudinally grooved cylindrical carrier 70
with the channeled margins of the sheet nested
together and nested within‘the channel of the
carrier. and securing theplate upon the carrier
in the so nested-together portions thereof.
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