Improvements in Platen Printing Machines.
Year: 1899

page_text: Date of Application, 18th Jan., 1899-Accepted, 15th Apr.,
1899
COMPLETE SPECIFICATION.
Improvements in Platen Printing Machines.
ERNST FISCHER of 3, Wertherhofstrasse, Barmen, Germany Manufacturer,
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 that class of printing presses in which a single blank
is fed or a pile of blanks is placed on a platen which is mechanically raised and
pressed against the types. The object of my invention is to provide improved
mechanism whereby the platen is raised and lowered said mechanism including
as a member a pneumatic cylinder linked to the platen the piston of the cylinder
being worked in such a manner that compressed air is produced in it which lifts
the platen and in expanding allows it to go down. The platen may be set
in and out of work by letting off the compressed air by means of a hand or foot
worked shipping device without stopping the motion of the printing machine.
The particular features in which my invention consists will be hereinafter
more fully described and pointed out in the claims at the end of this specification.
Figure 1 is a vertical section through the complete printing machine,
Figure 2 is a vertical section taken on a right angle of Figure 1,
Figure 3 is a side elevation of the machine,
Figure 4 is an enlarged detail chiefly to show the pneumatic cylinder and its
fittings,
Figure 5 and 6 show a modification of my invention.
Similar characters designate the same parts in all the figures.
Referring to the drawings the frame work I of the machine of suitable shape
to contain the working parts is mounted on stands or legs 2. It has bearings and
a supporting arm 4 for the shaft 3 which is fitted with a loose and fast pulley 5, 6
in order to be set in and out of motion by a shipping device 7.
To the shaft is keyed a pinion 8 co-operating with a toothed wheel 9 on a
shaft 10 which is journalled in the frame 1. The shaft 10 has a cam 11 which
is instrumental in operating a forked lever 12 the two arms of which engage
levers 13 that are fulcrummed to a shaft 14 securely mounted in the head of
frame 1. To the frame is turnably fixed in a slanting position the ink table 15
of circular form which is driven by a ratchet and pawl the latter being not shown
in drawing. The levers 13 are provided with the inking rollers 16 which by means
of cam 11 and lever 12 is alternately brought in contact with the ink plate 15
and the type bed which is fastened to the bottom face C of the frame head in a
usual manner. Underneath the type bed is horizontally located the platen 17
having downwardly extending guide arms 17" by which it is vertically guided in
a corresponding groove at the inner sides of the machine frame.
So far the
machine is old and well known. The new and characteristic features are the
means by which I undertake the vertical motion of the platen 17. For this
purpose to the lower face of the platen is cast an eye 19 which is connected by a
bolt r to two flat bars 20 which are arranged from both sides of the crossing
rib e.
To the bottom ends of bars 20 is hinged by means of an eye 22 and a bolt's

page_text: ;
a cylinder 21 being closed at its top end but open at its bottom so that a piston 23
may enter the cylinder. The rod 24 of this piston is coupled to the inner arm
of a double armed lever 25 which is fulcrumed to a shaft 26. The outer part of
lever 25 has connection to a rod 27 which by means of a slot surrounds the shaft 10.
Said shaft carries two differently shaped cams 28, 29 the first one being conform
in shape with cam 11 and each of them being engaged by lever 27 by means of
rollers so that one cam makes the lever 27 to travel up and the other down and
to move correspondingly the piston 23. The cylinder 21 is provided with an
extending box 30 containing the seat for a valve 31 the stem 32 of which of square
shape being guided in said box carries a disk 33 between which and the cylinder
wall a coiled spring 34 is inserted. This spring keeps the valve 31 always in a
closed position.
In front of the spindle 32 is hinged to a support 35 a vertical flat bar 36 which
is provided with a knob 37 and bears against said spindle 32. In a traverse 38
of the legs 2 is vertically guided a rod 39 having at its rear end a treadle 40
whilst its upper end is coupled to a bell crank lever 41 which rests upon the bar 36,
a spring 41 draws the bar 36 against lever 41.
Having thus described the construction of the machine I shall now proceed to
explain its working:
The printing press is set in motion by the shipping device 7. Cam 11 operates by
means of levers 12 and 13 the inking rollers 16 which travel from the intermit-
tently rotated inking plate 15 to the type bed providing the latter with
ink; lever 27 being. lowered by means of cam 29 pushes the piston 23 upwards
which first produces in the cylinder a quantity of compressed air and then together
with this air raises the cylinder 21 and the platen 17 hinged thereto, so that the
blanks either a single one or a pile resting on said platen are pressed against the
type bed and printed. The lever 25 in going down with its inner end lowers the
piston allowing the air to expand and correspondingly the cylinder to go down with
the platen.
Now I am able to vary the pressure which is exerted by the platen by adjusting
the rod 27 on the slotted end of lever 25 the latter being then more or less oscillated
and the pressure more or less strong. By this means always a sharp and clear
print may be obtained as the compressed air in the cylinder 21 actuates like an
elastic cushion on the platen so that its pressure is always the same even if a pile
of blanks is successively diminished.
The motion of the platen may be ceased without stopping the machine. This
is done either by hand or by foot in operating the knob 35 or the treadle 40. In
both cases the bar 36 is pushed forwards and the valve lifted from its seat so that
air may escape and the cylinder with the platen go down. It remains in this
position until the knob 35 or treadle 40 are released so that the valve 31 may be
closed by the spring 34 and the piston which during this time travelled up and
down ineffectually produces again compressed air which acts on the platen as
before described.
The printed blanks are delivered either by hand or mechanically. For the
latter purpose I have made the arrangement illustrated in Figure 3. I fix in the
head of the frame a tube 70 which is fitted with a mouthpiece and has connection
by a hose 42 to a pump or bellow (not shown in drawing) which being driven
by a connecting rod u and a crank disk 71 from the shaft 10 produced a vacuum
in the hose 72 by which the blank is withheld at the mouth piece and forcing air
stream which released the blank. The printed blank is also withheld by the
tube 70 so that a picker 43 of known construction the shants i of which are opened
and closed in any convenient manner can' seize the blank and take
it off after the vacuum in the hose has changed by a forcing air
stream. For this purpose said picker is attached to a lever 44
which engages a rod 45 that is linked to a lever 46 which is loosely
stuck on shaft 3. Lever 46 is fitted with a projection n which is in contact with a
cam 47 keyed to shaft 10 by means of a coiled spring 48. The co-operation of

page_text: cam 47 projection n and lever 46 causes the starting on of the gripper 43 to the
mouthpiece of pipe 70 as will be easily understood from the drawing whilst the
starting off of the gripper is done by the spring 48 after projection n engages
the depression of cam 47.
My invention is also appliable to especial large printing presses with a corre-
sponding heavy platen. In such a case I arrange a plurality of pneumatic
cylinders 50 Figures 5 and 6 which I attach in the manner to the platen as before
described. The pistons 49 are practically coupled to a common bridge 51 which
is actuated in the same way as before by one or more levers 52. The valve
spindles 55 are simultaneously operated by a horizontal lever 60 fitted with baffle
plates 61. The lever 60 may be shifted by the treadle lever 62 rod 64 and angle
lever 63.
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:-
1) In a plate printing machine a horizontal or slanted platen a pneumatic
cylinder hinged thereto, a piston engaging said cylinder and means to travel the
piston for the purpose specified.
2) In a plate printing machine a horizontal or slanted plate a pneumatic
cylinder hinged thereto a piston engaging said cylinder and means to travel the
piston, a valve fitted to the cylinder and closed automatically and means to open
the valve either by hand or foot shipping device for the purpose as illustrated
and set forth.
3) In a plate printing machine a horizontal or slanted platen a plurality of
pneumatic cylinders hinged thereto a bridge or other suitable means engaging
all pistons of said cylinders means to travel the bridge and means to operate all
valves of the cylinders simultaneously substantially as set forth and for the purpose
described.
בזי
L 1
1000