Improvements in Cylinder Printing Machines.
Year: 1889

page_text: Date of Application, 15th Oct., 1883-Accepted, 23rd Nov., 1889
COMPLETE SPECIFICATION.
· Improvements in Cylinder Printing Machines.
R CALVERT BARON COTTRELL, of 29 Elm Street, Westerley, in the County of
Washington and State of Rhode Island, United States of America, Manufacturer
of Printing Machines, 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 partly applicable to all stop cylinder printing machines but is in
its entirety applicable to those machines in which the impression cylinder makes two
complete revolutions and afterwards stops during the time occupied by one recipro-
cating movement of the bed, back and forth. In such a machine a toothed starting
lever engages a toothed sector or series of teeth upon the cylinder for the purposes of
starting forward the cylinder at a slow speed and of afterwards slowing up the
cylinder and bringing it to a stop. During the direct or forward movement of the
bed, it gears with and rotates the cylinder to print and commences the delivery of
the printed sheet and then the cylinder is raised directly and entirely out of gear
with the bed and its revolution is continued to complete the delivery of the printed
sheet and complete the two revolutions of the cylinder and bring the latter to the
position in which it stops with its receiving, edge in feeding position while the bed
makes its return movement.
The principal object of this invention is to provide for the starting of the cylinder
with a very slow motion and to so gradually accelerate the velocity of its rotation
that it is brought to printing speed before coming into gear with the bed rack without
any shock occurring either in the starting of the cylinder or in its coming into gear
with the bed rack, or at any intermediate stage.
My improvement consists in certain means hereinafter described and claimed
whereby the above-mentioned object is accomplished, and in the combination with the
impression cylinder as hereinafter described and claimed of lift mechanism for raising
and lowering the cylinder from and towards the bed and a locking mechanism for
holding the cylinder solidly down during the printing and liberating it to allow it to
be lifted after printing.
The accompanying drawings illustrate the application of my improvements to a
printing machine in which the cylinder makes two complete revolutions and afterwards
stops during the time occupied by one reciprocating movement of the bed back and
forth. Such parts of the machine as are not necessary to illustrate my improve-
ments are omitted from the drawings.
Figure represents a longitudinal vertical section of the machine taken in the
line Figure 2.
Figure represents a horizontal sertion taken below the cylinder and bed but
showing the mangle rack motion for driving the bed and the mechanism for operating
the starting and stopping dever
:
Figure represents a longitudinal vertical section taken in the line y, y of figure 2
showing the starting and stopping lever and its actuating mechanism and the lift
and locking mechanism for the cylinder..
Figure 4 represents a transverse vertical section in the line, of Figure 3 showing
part of the cylinder and its lift, and locking mechanism.
Figure represents a transverse: vertical section of the machine in the line * * of
Figure 1 but showing the cylinder and, its driving gearing in full.
Figure 6 is a side view showing the lift and locking mechanism of the cylinder.
Figure is a perspective view of the gearing shown in Figure 1 but showing its
members in a different position.
Figure S is a side view of the starting lever and the toothed sector on the cylinder,

page_text: with which said lever gears showing them in a position different from that shown in
Figure 3.
Similar letters of reference designate corresponding parts in all the Figures.
A designates an impression cylinder which is smaller than those usually employed
in stop-cylinder presses and which is mounted upon a shaft A' as shown in
Figures 1, 3 and 5. This shaft A is journalled in boxes which are fitted to rise
and fall a short distance in suitable guideways or housings a formed in the cylinder
frames B which are mounted upon side frames 13 of the machine.
C designates a reciprocating bed which is arranged to travel
suitable
mpon
bearers B², forming part of the fixed framing of the machine and having provided
upon it a bed rack c which is adapted to engage during printing with a gear wheel c¹,
which is secured fast to the cylinder shaft A' and which may be considered as a
fixed part of the cylinder. The reciprocating bed is to have imparted to it a move-
ment at a uniform speed as distinguished from a variable movement such as is
imparted by a crank and as here represented a rack and pinion movement of the kind
known as the napier" or "mangle" movement is employed.
The bed C has depending from it a hanger C¹ upon which the rack C is carried,
and with the rack there engages a mangle pinion C³ upon a knuckle shaft C4 which
is jointed at to the main shaft C5 of the machine on which is usually placed a
driving pulley.
Designates the usual cam shaft of the machine which is driven from the main
shaft C. as best shown in Figure 2. 63 designates a fixed stud upon which are
mounted so as to rotate as one, wheels 4, d. Upon the main shaft C is a
pinion which engages with the larger wheel and the smaller pinion
rotating with the wheel e engages with a larger wheel upon the cam shaft D.
By this arrangement of gear wheels, a speed very much slower than that of the
main shaft C is transmitted to the cam shaft D, which may make one revolution
during each complete movement of the bed C, back and forth. For starting and
stopping the cylinder A, I provide a starting lever E which is fulcrummed upon a
pin e secured in one of the side frames and upon the upper end of this lever E
is a toothed sector or series of teeth *, **, which engage with a sector et, c**,
upon the cylinder as best shown in Figure 3. This starting lever E is operated
by a gab hook E' which is fulcrummed at upon a cam actuated bar E and
engages a pin upon the starting lever E. The cam actuated bar E² is fitted to
slide in suitable guides and has in it a slide or guide-way which reciprocates
upon a block fitted on the cam shaft D.
The cam shaft 1) takes the place of the cam shaft commonly employed in stop-
cylinder machines but as it is desirable in carrying out this invention to impart
more than the usual length of movement of the starting lever, I propose here to
employ and have here represented upon the cam shaft, gear wheels or toothed
cams E, E such as are shown in Figures 1 and 3. One of these cams E³, is
fastened upon the cam shaft D and the other cam E is pivoted upon the pin el
fast upon the bar E². The cams E3, E+ have plain bearing surfaces ell which are
upon the pitch line of their teeth and inasmuch as the throw to be produced is
divided between the two cams a very much smoother and easier cam motion can
be obtained than would be possible with the large cam upon the shaft D such as
is usually employed acting against a simple truck-roll in the bar E. The cams E³, E+
serve to move the bar 2, toward the right hand in the drawing, Figures 1, 2 and 3
and a return movement of said bar may be produced by another cam or by a
spring applied between the bar E2 and a fixed part of the machine framing as
shown in Figures 1 and 3.
The toothed sector or series of teeth 3, 3* herein before mentioned on the lever E
is made in the form of an are concentric with the fulcrum pin e from the end e³, about
half way to the other end and thence the distance of the pitch line of the teeth from
the fulcrum e increases. The toothed sector or series of teeth, on the cylinder
is concentric with the cylinder from the end et, for a distance corresponding with the
concentric portion of the teeth of the sector e³, c³* and thence the pitch line of the
2

page_text: teeth approaches the centre of the cylinder so that it will continue in gear with the
sector or series of teeth on the lever throughout the whole length of both.
The effect of the form of the two sectors or series of teeth c³, e* and et, e** will be
hereinafter more fully explained.
Upon the side of the machine opposite the starting lever E is a train of gearing by
which the revolution of the cylinder is continued after the latter has been started by
the starting lever and until it comes into gear with the bed. This train which
I will now proceed to describe is shown in Figures 1 and 5 but more plainly in
Figure 7.
Mounted upon a fixed stud or pin f there is a large gear wheel F which engages
with a pinion F2 on the main shaft C of the machine. This pinion is of the same
pitch diameter as the knuckle gear or mangle pinion C³, hence its pitch line has the
same speed as the bed and therefore the pitch line of the large wheel F has the same
speed as the bed or the speed which the cylinder must have when the cylinder gear e¹
meets the bed rack c. Fast to the gear wheel F is a gear wheel F of half the pitch
diameter of the large gear wheel F. This gear wheel F1 gears with a small gear
wheel F3, turning loosely on a fixed stud f3 and the said gear wheel gears with
another gear wheel F turning loosely upon a fixed stud f. Opposite this gear
wheel there is fast to the cylinder a concentric toothed sector F which is capable
of gearing with the said gear wheel F. This sector has a pitel radius equal to one-
halt that of the cylinder gear c'. Secured to the gear wheel F is an excentric
sector and secured to the sector 15 or otherwise secured to the cylinder is an
excentric sector F which is the counterpart of that F. These excentric sectors are
so arranged that they may gear with each other as shown in Figure 7.
The gear wheel F¹ being one-half the diameter of the gear wheel F and being fast
to it, its pitch line will have one-half the speed of that of the gear F. The gear F
being but an intermediate gear for changing the direction of the gear wheel F will
have the same pitch line speed as that F that is, one half the pitch line speed required
for the cylinder gear e when the latter meets the bed rack c.
The
The concentric sector F5 having a pitch diameter equal to one-half that of the
cylinder gear it follows that when the teeth of the said sector are engaging in the
teeth of the gear wheel, F, the cylinder will have the same speed as the bed.
end 12 of the pitch line of the sector Fº coincides with the pitch line of the gear
wheel F and the pitch line of the other end 13 of the said sector has one-half of the
radius of the said gear wheel and hence the end 13 will have half the velocity of
the pitch line of the gear wheel F or one-quarter of the velocity of the surface of
the cylinder gear c¹. The pitch line of the excentric sector F7, at the end 15 coincides
with the pitch line of the concentric sector F5 and at the other end 14 has a radius
corresponding with that of the pitch line of the gear wheel F.
I will next describe the mechanism for lifting and lowering the cylinder and
for locking it in its lower position and will afterwards describe the operation of
printing.
The lift mechanism itself does not differ essentially from that commonly employed
in two revolution presses. From the cylinder boxes, rods h extend downward, as best
shown in Figure 6, and have applied to them springs h¹ which bear at their lower
ends upon a portion of the main side frames B₁, and at their upper ends upon
shoulders upon said rols h. The pair of rods upon each side of the press extend
directly downward through openings in the side frame and are secured at their lower
parts in a bearing block which supports a rock shaft as best shown in Figures 5
and 6. This rock shaft is cranked downwards and extends across the machine, as
shown in Figure 5 at 7 and between each end of the rock-shaft and the adjacent
fixed portion of the side frames, are a pair of toggle levers 48 one of which is
formed upon the rock-shaft, while the other is secured in the framing. The lifting
is performed by a gab-hook H. upon a bar or rod H which is operated by a cam d
upon the cam shaft D, as shown in Figures 1 and 2. The cam d acts upon truck
rolls upon the hooked bar H₁ and the gab-hook engages the cranked portion of
the rock-shaft. By this gab-hook the rock shaft h, is rocked back and forth

page_text: When
alternately straightening and breaking down the pairs of toggle levers 48.
such toggle levers are broken down, as shown by dotted lines in Figure 3 and in full
outlines in Figure 6 the springs by their force exerted upon the rods h, lift the
cylinder boxes a sufficiently to carry the wheel c' entirely out of the bed rack c, but
when the toggle levers are straightened or brought into line the force of said
springs is overcome and the cylinder boxes a, are drawn down and held solidly
down against stops consisting of screws / inserted in the bottom of the slideways a
to which the cylinder boxes a are fitted.
When the cylinder boxes are drawn down as just above described it is desirable to
lock them still more securely in their lowermost position, and to this end I apply to
each cylinder box a lock consisting of toggle levers jointed together and having a
fixed joint upon the cylinder frame B and a movable joint jupon the adjacent box a
as best shown in Figure 6. In front of the cylinder is a rock-shaft, which extends
across between the cylinder frames B and this rock shaft has arms which are each
connected by a rod with an arm j extending from the fixed joint of the pair of
toggles on each side of the machine. To one of the arms on the shaft j¹ is connected
a rod which extends downward and has a truck-roll je upon which acts a cam
fixed upon a longitudinal shaft J, as best shown in figures 3 and 4. At the sanie
instant that the rock-shaft straightens or brings into line the toggle levers 3 and
thus brings down the cylinder boxes a, the rod is drawn down by the cam and
by the downward pull upon the rods the pairs of toggles which are applied to
said cylinder boxes are straightened and the boxes are held solidly down upon
the stops /.
I will now describe the operation of printing.
In the position of the parts shown in Figures 1, 3, 4, 5, 6 of the drawing, the
cylinder is raised out of gear from the bed rack and supposed to be at rest in the
position in which it has just taken a sheet and the bed is still continuing its return
movement to the right, that is to say, in a direction the reverse of that in which it
moves to print the sheet; the starting lever E is in its central position with its sector
in gear with the sector 4, *, of the cylinder at the point where their respective
concentric and excentric portious meet, and the cams E, E, by their rotation in the
direction of the arrows shown in Figure 3 are just about to move the starting lever to
the left and cause the concentric portions of the said sectors to move the cylinder
forward in the direction of the arrow shown near it in Figures 1 and 3 and the said
movement increases gradually in speed by reason of the form of the cams.
The speed
to which the cylinder is thus brought depends on the form of the cams but with such
cams as are shown, it will be about one-fourth the speed of the bed.
Up to this time the excentric sectors F6, F shown in Figures 1 and 7 are out of gear
with each other but they come into gear at their points 13, 14 as shown in Figure 7
just as the starting lever is passing out of gear with its corresponding toothed sector
on the cylinder. The radii of the pitch lines of the sectors F, F, at the points 13, 14
is, as hereinbefore described such that the velocity of the movement then imparted to
the cylinder through said sectors will also be one-quarter that of the printing speed so
that it corresponds with the velocity imparted through the starting lever at the time
the latter passes out of gear.
After the sectors F6, F7, have become engaged, the sector F drives the cylinder at
a constantly increasing velocity till the end 22, of the concentric sector F, comes into
gear with the gear wheel F and brings the cylinder to the same surface speed as the
movement of the bed and its rotation at this speed is continued by the gear F and
concentric sector F. The cylinder having now been depressed by the action of the
toggle levers and locked down by the locks i, produced as hereinbefore described,
and the movement of the bed having been reversed, the cylinder gear e then runs into
gear with the bed rack without shock or jar and during the movement of the cylinder
thus produced the printing takes place.
After the cylinder has made somewhat more than a complete revolution in gear
with the bed and the printing has been completed, the toggles are bent and the
cylinder is lifted to carry its gear out of gear with the bed rack but before this

page_text: lifting takes place the starting lever which has been previously thrown over to the
right beyond the cylinder, moves to the left as indicated by the arrow in Figure 8,
and just as the cylinder is lifted completely out of gear with the bed rack. the said
lever brings its sector into gear with the corresponding sector of the cylinder at the
points, the lever sector then moving in the same direction with the cylinder.
The cylinder has up to this time been moving with a surface velocity equal to that of
the bed, but the end e*, of the cylinder sector being about half way between the
centre and the surface of the cylinder, will have about half the velocity of the surface
of the cylinder, therefore the end of the starting lever sector will have to move at
about half the velocity of the surface of the cylinder in order to engage with the
end of the cylinder sector. Then as the cylinder and the starting lever move to
the positions shown in Figures 1 and 3, the starting lever can be holding back on the
cylinder to bring the latter to rest in the last mentioned position in which the lever
stops. The stoppage of the cylinder may be assisted by a friction brake as in
ordinary stop cylinder presses.
It may be here stated that while in carrying out this invention, I prefer to make
the toothed sector on the starting lever and the corresponding one on the cylinder
with their pitch lines of irregular or compound curvature as herein described, the
said sectors might have their curvatures regular or concentric as in other stop
cylinder presses.
It will be obvious that in applying my invention to a stop cylinder press in which the
cylinder makes but one revolution to each complete movement of the bed, back and
forth, and for each printing, the lift and locking mechanism for the cylinder would
be omitted.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
First. The combination with the main shaft and impression cylinder, the bed having
a rack for gearing with and driving the said cylinder during printing and a cam-
actuated starting lever for starting and stopping the cylinder, of excentric gearing
between and geared with the main shaft and cylinder for driving the latter at a
gradually increasing speed after it has been started by the starting lever, substantially
as herein described.
Second. The combination with the main shaft and impression cylinder, the bed
having a rack for gearing with and driving the cylinder during printing and lift
mechanism for raising the cylinder after printing, of excentric gearing between and
geared with the main shaft and cylinder for driving the latter at a gradually increasing
speed while out of gear with the bed and a cam-actuated starting lever for starting
and stopping the cylinder, substantially as herein set forth.
Third. The combination with the main shaft and the impression cylinder, of the
concentric sector F, fast to the cylinder, of a gear wheel for gearing with said sector
and geared with the main shaft to drive the cylinder at printing speed, two excentric
sectors one fast to the cylinder and the other carried by said gear wheel for the
purpose of driving the cylinder at a gradually accelerated velocity; substantially as
and for the purpose herein set forth.
Fourth. The combination with the impression cylinder and its journal boxes and
mechanism substantially as herein described for raising and depressing said boxes, of
locking devices consisting of toggle levers applied directly to said boxes independently
of the said raising and depressing mechanism for holding the cylinder down during
printing, substantially as herein set forth.
Dal 1 th Lintulan 1000
HASELTINE, LAKE & Co..
45, Southampton Buildings, London, Agents for the Applicant.