Improvements relating to Printing Machines.
Year: 1896

page_text: Date of Application, 19th May, 1896-Accented, 1st Aug., 1896
COMPLETE SPECIFICATION.
[Communicated from abroad by C. B. COTTRELL & SONS COMPANY, a corporation
organized under the laws of the State of New Jersey, and doing business at
No. 41 Park Row, in the City of New York, State of New York, United
States of America.]
Improvements relating to Printing Machines.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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 relates to tympans which are shifted on the impression cylinders
of printing machines as often as it may be desired to present a clean tympan surface
on the operative portion of the cylinder.
The object of the improvement is to provide for clamping the tympan to the
cylinder throughout as much of the circumference of the latter as iucludes the
impression surface and thereby to more effectually counteract all tendency of
the tympan to creep or be slightly shifted upon the cylinder by any drag produced
upon it in the act of printing.
The invention is illustrated in the accompanying drawings as applied in connection
with a shifting tympan and such mechanism for shifting it as is illustrated and
described in the Specification of prior Patent No. 20,238 dated October 23, 1894,
such mechanism including a supply roller and feed and take-up mechanism by
which the tympan consisting of a rolled-up web is taken from said roller.
In the said drawings,
Figure represents an end view of an impression cylinder and such parts
attached and contiguous thereto as are necessary to illustrate our invention, the
head of the cylinder being represented as having parts broken out to expose the
parts within.
Figure 2 is a plan view of a portion of the said cylinder and parts.
Figure 3 represents on a larger scale, a plan view of one of said parts which
will be hereinafter explained.
A is the impression cylinder; 6 the tympan; e the supply roller on which is
the clean portion of the tympan which has not yet been delivered to the exterior
of the cylinder; d the take-up roller on which the soiled portion of the tympan is
taken up; ef the feed rollers. These rollers which are all within the cylinder
and are shown in Figure 1 in dotted outlines only, have their several journals
fitted to bearings in or attached to the cylinder ends.
is the ratchet wheel on the supply roller journal c. This ratchet wheel
might be mounted loosely on the journal under the control of a spring as described
in the hereinabove mentioned Patent No. 20238, but for the purpose of the present
invention this mounting of the ratchet wheel is not material and the said wheel
may be considered as fast upon the journal c*. J J designate a locking pawl
consisting of a lever working on a fulcrum pin ji on one end of the cylinder. The
arm J of the said lever has teeth ; which engage with the said "ratchet wheel c,
said teeth and those of the said ratchet wheel being set in a direction to hold the
supply roller against any tendency to unwind the tympan. The arm J' of the
said lever has applied to it a spring which operates to press the teeth ; of

page_text: the lever into engagement with the ratchet wheel e. The arm J of the said lever
has pivoted to its outer end a slide which is capable of running against either
the inner or outer periphery of the stationary interrupted circular track D' which
projects from the stationary gear D with which the feed and take-up rollers are
geared to derive motion through the revolution of the cylinder. When the teeth j
of the locking pawl or lever J J are in engagement with the ratchet wheel c³, the
slide is in position to run outside of the track D', but when the said slide runs
on the inner periphery of the track D it holds the locking pawl out of engagement
with the said ratchet wheel. The said ratchet wheel, locking pawl and circular
track are like the corresponding parts described in our Letters Patent No. 20,238
hereinbefore referred to, but I have found it necessary to so far describe them here
in order that it may be understood how the present inventim may be applied in
connection with automatic tympan shifting mechanism.
The feed and take-up devices of which the rollers e constitute essential parts
are not involved in the pre-ent invention and therefore neel n further description
beyond saying that they may he and are represented the same as in said Letters
Patent.
Bare clamping hands which constitute the principal feature of this invention
fur clamping the tympan to the cylinder at as many lateral intervals as may ha
desirable throughout as much of its circumference as includes the impression
surface. There may be for example, one of these hands just within each elge of
the tympan and one at the middle of the width thereof. The said bands are
preferably of metal of great tensile strength, steel for instance, and I prefer to
make them of flat ribbon or tape form. They are severally attached at their
opposite ends to and within the cylinder and extend all the way over the portion
of the tympan which is exposed outside of the cylinder. They are represented as
attached at one end to the brackets C which contain the bearings of the gripper
rod C¹, and as connected at the other end i with levers E, one for each band, which
are fulcrumed on a rod F which is arranged lengthwise within the cylinder in
suitable bearings in the ends thereof and at such intervals as may be necessary
between the ends. On one end of the fulcrum rod or shaft F outside of the
cylinder there is fast a lever arm F with which is connected a rod n working
through a guide fast on the end of the cylinder. Between this guide ³ and a
collar on the rod, a spring n' is coiled upon the said rod, the said spring acting
on the lever arm Fi with a constant tendency to tighten up all the tympan clamping
bands. The lever arms E are loose on the fulcrum rod F but for each one of
them there is fast on the said rod an arm F' upon which bears an adjusting screw n³
which is screwed through a lug n on the arm E. By screwing up these set screws
the several bands may all be adjusted to a uniform tension.
The lever arm F is connected by a rod p with one arm of a lever P which
works ou a fulcrum P¹ on the end of the cylinder, the opposite arm of the said
lever having pivoted to it a slide p' which may run either inside or outside of the
track D'. When the lever P is in position for the slide to run on the outside
of the track, the said lever acting through the rod p on the lever arm F¹ causes
the lever arms F2 E to hold the tympan clamping bands B tight upon the tympan
so that the latter is immovable, but when the said lever P is in position for the
slide p¹ to run on the inside of the track the rod p overcomes the force of the
spring and leaves the said bands slack so that the tympan can be shifted on
the cylinder by the means provided for the purpose. The arm J of the lever .J.J
has on one side of it a stud or projection p³ which projects over the lever P for the
purpose of producing the action of the said levers the one upon the other as will
be presently described.
In carrying out this invention there may be employed any suitable means for
engaging the tympan feed and take-up rollers with and disengaging them from
their operating mechanism and any suitable means for throwing the slide of the
locking pawl or lever J J into the opening 10, 11 of the circular track D at the
proper time for disengaging the said pawl or lever from the ratchet wheel C and

page_text: liberating the supply roller preparatory to the shifting of the tympan and tor
re-engaging the said pawl or lever with the ratchet wheel for stopping said roller
after shifting; but we propose generally to employ for both of the above purposes
the mechanism which is fully described in our Letters Patent herein before referred
to and which therefore need not be herein described. No additional or other
nechanism beyond that, except the stud or projection p hereinabove mentioned
on the said pawl or lever, is required to operate the lever P which controls the
operation of the clamping bands B. This operation of the pawl lever and the
band operating lever P, we will now describe."
The cylinder rotating in the direction of the arrow shown upon it in Figure 1,
we will suppose the pawl lever J Ji and the band operating lever P to be in such
positions that their slides je anl pl may run on the outside of the circular track D',
as shown in the said figure, the teeth j of the pawl lever stopping the ratchet
wheel and the band operating lever P holding the bals B in action on the
tympan until the time arrives for shifting the latter when the pavl lever will be
automatically disengaged from the ratchet wheel can 1 the bands B losenel, the
said disengagement and automatic loosening being permitted by the opening 10, 11
in the track which allows the slides j and p¹ to enter and run on the interior of the
said track.
The pawl lever J J' is or may be disengaged by the same means described in
the Letters Patent herein before referred to, but that disengagement does not take
place until the slide p' of the band operating lever P has passed the point 10 of the
opening in the track because up to that time the pawl lever has been held in
engagement by the stud or projection p³ on the band operating lever P; but as
soon as the slide p' has passed the said point 10, the band operating lever is
left free to be moved to slacken the bands B by the action upon it of the stud or
projection p³ on the band lever. The slides and p' both having arrived opposite
the opening 10, 11, in the track D' may both pass into the interior of the track.
As long as the slides both run inside the track, the ratchet wheel c2 remains free
and the pawl lever holds the band operating lever in a position to slacken the
bands B and leave the tympan free to be shifted by the movement of the feed and
take-up rollers which then takes place, but just before the shifting of the tympan
is completed, the slide j running on the inside of the track, passes the point 10 of
the opening in the latter and permits the spring to produce automatically the
A short interval of
re-engagement of the pawl lever with the ratchet wheel c².
time then elapses before the slide p' of the band operating lever passes the point 10
and permits the lever arm F on the rod F to be operated upon by the spring n³ for
the purpose of tightening the bands upon the tympan by the action of the lever
arms F E. After this, the continued revolution of the cylinder carries first the
slide and afterwards the slide pl past the point or end 11, of the opening in the
track and allows the said slides to run on the outside of the track so that during
successive printing operations both the pawl lever J J and the band operating
lever P are positively locked and the supply roller being thus secured against
letting off the tympan and the tympan being positively clamped to the cylinder
until the proper time for again shifting the tympan.
We
In "making ready" and when it is desired to change the tympan, the bands B
must be disconnected at one end so that they may be taken off the tympau.
have represented the bands as clamped to the ends of the lever arms E by screws q
and as clamped to the brackets C by screws r. To provide for the disconnection
the bands are provided at the ends h, as shown in the enlarged plan view Figure 3,
with slotted clasps B', the fastening screws which may have their heads so formed
as to be operated by hand, passing through the slots s in the clasps and the said
slots being enlarged at one point in their length sufficiently to allow them to be
slipped over the heads of the screws r when the screws are unscrewed and the bands
are slackened.
In some cases a single clamping band might be sufficient and in such a case we
would apply the band at the middle of the width of the tympau.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspandents, I declare that what I claim is :-
1. The combination with the impression cylinder and a tympan applied thereto,
of a clamping band extending over that portion of the tympan which is exposed
outside of the cylinder, means for securing the said bind at one end to the cylin ler
and automatic means connected with the other end of said band for tightening and
loosening said band, substantially as herein described.
2. The combination with the impression cylinder, a supply roller in said cylinder
for supplying clean portions of the tympan, a take-up roller in said cylinder for
taking up the soiled portions of the tympan and automatic means for operating
said take-up roller, of a clamping band extending over that portion of the exterior
of the cylinder which receives the tympan and automatic means for tightening
and loosening said band, substantially as herein described.
3. The combination with the impression cylinder, and a tympan applied thereto,
of a plurality of clamping hands extending over the portion of the tympan which
is exposed cutside of the cylinder, means of attaching the ends of said bands to the
cylinder, means of tightening and loosening the several bands together and means
for separately adjusting the tension of the several bands, substantially as herein
described.
4. The combination with the impression cylinder and a tympan applied thereto,
of a clamping band extending over that portion of the tympan which is exposed
outside of the cylinder, neans for securing the said band at one end to the cylinder,
a device connected with the ot!.er end of the said band for tightening the said band,
a lever having its fulcrum on one end of the cylinder and connected with said
tightening device, a st tionary circular track outside of the cylinder and a slide ou
said lever for running inside or outside of the said circular track to hold said
tightening device in or out of operation, substantially as herein described.
5. The combinatior with the impression cylinder and a tympan supply roller
therein furnished with a toothed wheel of a tympan clamping band extending over
that portion of the exterior of the cylinder which receives the tympan, a pawl lever
on said cylinder for engaging with said toothed wheel, a lever on said cylinder and
connections between said lever and band for tightening and slackening said band, one
of said levers having a projection through which each is capable of acting on the other
for the engagement and disengagement of the toothed wheel and the tightening and
slackening of the band, substantially as herein described.
6. The combination with the cylinder and a tympan clamping band having one
end secured within the cylinder, of a fulcrum rod or shaft and bearings therefor
within the cylinder, a lever arm on said rod or shaft connected with the other end
of the said band, and a spring applied to the said rod or shaft for producing the
tightening of said band, substantially as herein described.
7. The combination with the cylinder and a tympan clamping band having one
end secured within the cylinder, of a fulcrum rod or shaft and bearings therefor
within the cylinder, an arm on said rod or shaft located within the cylinder and
connected with the other end of the said band for tightening and slackening it, a
second arm on said rod or shaft outside of said cylinder, a stationary circular track
outside the cylinder, a lever on and outside of the cylinder, a connection between
the said second arm and the said lever and a slide attached to said lever for running
on the inside or outside of said circular track for maintaining the tightness or
slackness of the clamping band, substantially as herein described.
Dated this 10th dor of Nov 1900
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.