Improvements in or relating to Printing Machines.
Year: 1893

page_text: Date of Application, 29th May, 1893-Accepted, 1st July, 1893
COMPLETE SPECIFICATION.
Improvements in or relating to Printing Machines.
We, LEOPOLD SCHMIERS and HERMANN STEIN, of the firm of Schmiers
Werner and Stein, Manufacturers, of Dösener Weg, Leipzig, in the Kingdom of
Saxony, 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 has for its principal object, to automatically moisten the printing
plate or printing surface immediately after the removal of a printed sheet and
before a fresh supply of ink is applied to the printing surface by the rollers.
In the following description reference will be made to the accompanying drawings,
of which
Fig. 1 is a partial side view of a printing press provided with a moistening
appliance embodying this invention.
Fig. 7 is a plan of the same.
Figs. 2 to 6 represent details.
The apparatus used for this purpose, consists of three principal parts, as follows;
1. An appliance for producing a suitable air current or air pressure, such as a
bellows (as shown by the drawings), a fan or air compression pump.
2. An intermediate reservoir or air moistener (B, as shown in Fig. 1, or B¹ as
shown in Fig. 5).
3. An outlet pipe for air, together with a valve and controlling device.
The wind apparatus or blower C is set in motion by the carriage or moving
platform of the printing machine by means of an angle lever a. In Fig. 1 this
apparatus is a bellows enclosed in a casing and adapted to move up and down, so as
to draw in air and deliver it to a flexible pipe c which leads to a valve b attached
to the moistener B. The latter contains several transverse slides or partitions d
which are covered with fabric adapted to absorb and retain moisture (Swanboy).
For supplying moisture, the cover of the vessel B carries a water receptacle s
(Fig. 5) provided with a regulating cock t or a valve.
The water descending through the cock in the direction of the arrow, trickles
upon the transverse slides d covered with Swanboy, and collects at the bottom of
the pot B, from which it is let off periodically through a cock v.
and
The air which has passed through the moistener escapes through the outlet
hose pipe e into the air pipe A, Fig. 1, provided with a slot f (Fig. 3). The
latter allows the air to descend upon the printing plate D, Fig. 1.
On the cylinder axle are fixed a pair of cams g h which serve to control the
supply of air by acting on the throttle valve i (Figs. 2 and 3) through an inter-
mediate mechanism comprising a friction roller k, lever 1, connecting rod o and
lever m.
The wide part of the cams or the outer curve corresponds to the closing
position of the throttle valve, while the narrow part or the inner curve corresponds
to the opening position of the same.
The supply of air to the printing plate is regulated according to the size of the
latter.
In order to adapt the appartus for a shorter plate, the cam or eccentric h is
turned in the direction of the arrow, Fig. 4, thereby shortening the time during
which the friction roller touches the narrow part or the short radius of the cam ;
and causing the throttle valve to close earlier.
In setting the printing plate, the eccentric g (Fig. 4) should be so placed, that
its edge a', the centre of the printing cylinder and the gripping edge 61 are situated
in one straight line. The friction roller k mounted on the lever runs on both

page_text: cams or eccentrics (g and h) and is kept in contact with the same by a spring r
Fig. 2, while running on the recessed part of the eccentrics.
In Fig. 3 the position of the connecting rod o which corresponds to the open
throttle valve is indicated by dotted lines.
In this position, the compressed air enters the air supply pipe A and passes
through the slot f of the same (Fig. 3) down upon the printing plate moving in the
direction of the arrow Figs. 1 and 7. This escape of air continues until the rear
end of the printing plate is situated under the slot f, after which the friction
roller runs on the wide part or outer curve of the eccentric, and causes the
valve i to close, until the roller k again arrives at the narrow part or recess of the
eccentric.
Fig. 1 shows two alternative forms of the moistening pot B, the upright form (B¹)
indicated by dotted lines corresponding to the arrangement shown by Figs. 5 and 6.
Figs. 2 and 3 show on a larger scale the air supply pipe A, valve i and the
mechanism for operating the latter.
If the air moistener is omitted, and the wind chest or bellows connected directly
with the valve i, the apparatus may be used also for drying the printing plate, in
case the latter is too moist.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is;-
}
1. The improvement in the art of printing with automatic printing machines,
which consists in moistening the printing plate or surface by a blast of moist air
every time a printed sheet has been drawn off and before the printer's ink is again
rolled on to the said plate or surface, substantially as described.
2. In printing machines, an appliance for automatically moistening the printing
surface or plate by a blast of moist air, or for drying it by a blast of dry air
comprising in its construction a compressed air reservoir (B or B'), a slotted
distributing or discharge pipe (A) communicating with the said reservoir, a regulating
valve (2) interposed between the air receptacle and the discharge pipe, and
mechanism for automatically operating the said valve from the axle of the printing
cylinder, substantially as described.
3. The adjustable valve gear or regulating mechanism chiefly comprising a pan
of cams or eccentrics gh, friction roller k, lever 1, and connecting rod o, substantially
as described.
Dated this 23rd day of May 1893.
FAIRFAX & WETTER,
433, Strand, London, Agents.